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Dry Dock / Shipyard: Builds & Questions => Pleasure boats, Sports, Race, Power and Leisure Boats: => Topic started by: Ramon on July 12, 2009, 06:45:06 PM

Title: 1/8 scale hydroplane 'Atlas van Lines' build
Post by: Ramon on July 12, 2009, 06:45:06 PM
Hi All,

Those who’ve followed the ‘Huntsman’ thread will know that I have returned to model boats after a long thirty plus year lay off. Just before circumstances led to the decline in interest in the ‘70’s I was very keen to building a hydroplane – not sure what but it would probably have been from a Dumas kit. This was as a direct result of not being able to ‘keep up’ with the OPS 60 powered boat I had built around the 30 metre Naviga triangular course we had laid out. I took to just running the boat flat out in a straight line and have to say got a big kick out of doing so especially when the pipe ‘came in’.  I had made a tentative start on an outrigger for a Merco 35 but it never got past the basic body before work took me to Ecuador (Now you have to appreciate that's not exactly renowned as a haven for model boaters!) and all my ideas and ideals faded away.

Last year when I saw the boats run by the guy’s at the local water that desire to build that hydro immediately returned especially when I realised one of the guy’s – Martin, Mayhems’ ‘Mr Fid’ - had the same interest.

Something more ‘sedate’ had to come first hence the Huntsman but to be honest all my effort really went into finding out about hydros to wit the computer is as full of as much info and pics as I could find. It quickly became apparent that there was much more to choose from than Dumas. Not wanting to be seen as running before walking however I’ve kept the build of my first hydro well in the background but the recent post by Adam on his Miss Circus Circus  has led me to ‘declare my interest’

With the apparent interest shown in the Huntsman build I thought that this may also be of interest to those who have similar aspirations as well as hopefully to hear from those far more experienced when things appear to be going off track. This then is a build thread of my first attempt, albeit part retrospectively, based on the info I have found and the help I have received from others on this and the 'R/C Universe' forum’s.

That initial search of the net produced  a free downloadable plan on the Astec models site for the 1977 Atlas van Lines ‘picklefork’ hydroplane. This was/is available in several scales though all are for electric power.
I began by contacting a copy shop who just said “email the file and the rest is easy!” Two days later I received two sheets of full size 1/8 scale drawings for the princely sum of seven pounds! The original drawings appear to be drawn by CAD and have proved extremely accurate.

(http://lh6.ggpht.com/_XuA0NMLYOxg/SloU970I_QI/AAAAAAAACPU/q_X_DLjjasQ/s512/DSCN1547.JPG)

(http://lh4.ggpht.com/_XuA0NMLYOxg/SloU-uhTsRI/AAAAAAAACPY/e8AGvidxyQI/s512/DSCN1548.JPG)

(http://lh5.ggpht.com/_XuA0NMLYOxg/SloU_cXlyKI/AAAAAAAACPc/jqFDir8kNAE/s512/DSCN1549.JPG)

Construction began by making card templates from the drawing using carbon paper and then transferred the shapes to the ply. All ply is 3mm except the engine rails and inner transom which are 6mm

(http://lh4.ggpht.com/_XuA0NMLYOxg/SXzzhQYaCBI/AAAAAAAABac/5JF6RICWCVs/s512/DSCN1125.JPG)

These were then cut out to complete a kit of parts to build the basic frame work the main 'sides' being two laminations the inner of which gives the profile of the tunnel

(http://lh6.ggpht.com/_XuA0NMLYOxg/SXzzCplT4yI/AAAAAAAABZE/uHD58ZyL7vU/s512/DSCN1249.JPG)

They quickly and accurately assembled to produce the basic framework. Thought was given at this very early stage to the fuel system but more on that later.

(http://lh3.ggpht.com/_XuA0NMLYOxg/SXzy-8znxTI/AAAAAAAABYc/P5iXoszYpqk/s512/DSCN1244.JPG)

Let's call that enough to start with. Hope it's of interest and will prove useful to someone somewhere.

Back soon - Ramon


Title: Re: 1/8 scale hydroplane 'Atlas van Lines' build
Post by: martno1fan on July 13, 2009, 10:33:20 AM
Nice to see you started a thread on the build Ramon ,ill be watching with interest your work looks very clean and precise  :-)).Keep the pics coming  and good luck with it.Good tip on the source to have plans printed,might need to use that place myself.
Mart
Title: Re: 1/8 scale hydroplane 'Atlas van Lines' build
Post by: Ramon on July 14, 2009, 10:59:48 PM
Thanks for the compliment Mart

Managed to get into the workshop for a while today, even got some paint on the H--------------n - before it rained :((

Never mind here's a few pics on the AvL build to cheer things up :-)

Before work on the construction began a simple building jig was made from Contiboard. Two outer edges were cut off another piece and glued parallel with each other the same width apart as the tunnel. The two sides and the front and rear formers were used as an aid in setting the width. The two white faced outer edges of the rails were simply stuck down with thin cyano and it has proved more than adequate however the next one will have much deeper rails to allow for temporary fitting of the strut and rudder etc. during construction. The small ply patch is a front support for the side frames (both sides)

(http://lh3.ggpht.com/_XuA0NMLYOxg/SlzvQ9Wje-I/AAAAAAAACP8/6_JJu7dX1qU/s512/DSCN1550.JPG)

The parts were dry fitted on the jig to ensure alignment then the gluing began. It was decided to make two 6mm engine rails the width of the tunnel apart and to glue the sump strips to these from the outside - the hull is off the jig and laid inverted across it on the latter op.

(http://lh3.ggpht.com/_XuA0NMLYOxg/SXzzASSREqI/AAAAAAAABYs/qkQ76i1oMco/s512/DSCN1246.JPG)

(http://lh3.ggpht.com/_XuA0NMLYOxg/SXzzBIOKC5I/AAAAAAAABY0/x595i_Ro6XY/s512/DSCN1247.JPG)

(http://lh4.ggpht.com/_XuA0NMLYOxg/SXzzEWk-VmI/AAAAAAAABZU/o5cb7sn-06o/s512/DSCN1251.JPG)

The tunnel bottom skin being installed with the hull  now fitted inverted to the jig at the rear and supported on a spacer at the front. The sponson side rails were fitted at this stage and small 'fairing' blocks of hard balsa added.
(http://lh5.ggpht.com/_XuA0NMLYOxg/SXzzGB6wnCI/AAAAAAAABZk/BLYnmVlVV8k/s512/DSCN1253.JPG)

Turned back on the jig for a check and dry fitting of engine and fuel tanks but more on that later.

(http://lh3.ggpht.com/_XuA0NMLYOxg/SXzzImR4XXI/AAAAAAAABZ8/zTvNdNYdHN0/s512/DSCN1257.JPG)

Hope this is of interest - Ramon
Title: Re: 1/8 scale hydroplane 'Atlas van Lines' build
Post by: martno1fan on July 14, 2009, 11:09:38 PM
Loving your work Ramon,very clean and precise you put me to shame  %).Love the fuel tanks too,ive been thinking about using one of those allumium drinks bottles you can get them in pretty colours too  :-).Keep up the good work mate im def interested.
Mart
Title: Re: 1/8 scale hydroplane 'Atlas van Lines' build
Post by: Ramon on July 16, 2009, 11:25:18 PM
Mart, again, thanks for your compliment.
It is nice that there have been quite a few similar remarks but this is not about putting anyone to shame. I just feel that sharing what I am doing with others is so beneficial to all concerned including myself. I have had such informative and immediate feedback on questions – something that you don’t get writing for a magazine for instance (no, obviously haven’t done it for boats but yes, you probably guessed it, on the odd occasion for control line aircraft!) – that that is what makes the ‘forum’ such a modelling asset.

Enough, he said – the model………

(http://lh3.ggpht.com/_XuA0NMLYOxg/SYF6YQ3Me7I/AAAAAAAABdM/UK3BCuhlFMM/s512/DSCN1279.JPG)

At about the stage of the pic above I posted on the R/C universe forum and received some timely advice. This was with regard to the C/G position which I was informed should be no more than 2” aft of the sponson transom. The advice was to lighten the boat aft of this point and move the fuel tanks forward. The mass of fuel is now over the C/G point but obviously as it drains it will load toward the rear ends but the C/G shift should be minimal due to fuel usage.
I had intended to make each side from the transom to the sponson a water tight compartment but was assured that no matter how water tight I thought it would be water would eventually get in. On the basis that if it did it probably would not get out as quick a decision was made to cut out holes in between the formers to not only to aid lightening but also to allow the air to circulate after a dunking! Holes were cut in the bottom of each former to allow water to drain through to the sponsons and two suction baler tubes were later fitted to allow water removal using a syringe.

(http://lh5.ggpht.com/_XuA0NMLYOxg/SjwKRzb5rwI/AAAAAAAACH0/5bFIdLZ16Nc/s512/DSCN1289.JPG)

(http://lh4.ggpht.com/_XuA0NMLYOxg/SkfeTl_GATI/AAAAAAAACLg/QjQGROg7CRE/s512/DSCN1531.JPG)

The engine is hard mounted on ally plates let into very hard Beech bearers. The engine was bolted to the bearers and then the whole was epoxied in place. This ensures the crankcase is not distorted by pulling down onto misaligned bearers. The rails were a bit two narrow to get in a normal ally mount, the width dictated by the width of the tunnel sump. I don’t think this will be a major limitation, all my previous boats had hard mounts and I can’t remember any problems as a result – any thoughts anyone?
I have offset the engine slightly – all my previous boats showed a torque induced ‘twist’ or ‘list’ to the right and this may, hopefully, help eliminate or reduce that tendency. Besides the plan shows it but agreed it is the other side of the centreline! but it is electric!!

(http://lh5.ggpht.com/_XuA0NMLYOxg/SjwKcfRDuOI/AAAAAAAACI0/VCj3M63Q64Q/s512/DSCN1305.JPG)

Stringers were added to the outer edges to give the 'non trip' sides a better gluing area

(http://lh3.ggpht.com/_XuA0NMLYOxg/SjwKSWk5s5I/AAAAAAAACH4/Rb3KT7fYbck/s512/DSCN1290.JPG)

With the 1/16 ply non trips added it began to look a bit more like it should

(http://lh4.ggpht.com/_XuA0NMLYOxg/SjwKYTg-pbI/AAAAAAAACIc/LjjZG6jfHLU/s512/DSCN1299.JPG).

That's about it for now, still quite a bit to go before catching up to it's current stage.

Regards for now - all comments welcome - good or bad - Ramon


Title: Re: 1/8 scale hydroplane 'Atlas van Lines' build
Post by: martno1fan on July 17, 2009, 10:39:49 AM
Hi Ramon im loving your work shes looking great and i like the idea of been able to drain any water from the sponsons thats a good idea .A friend of mine drills a drain hole in the transom sponsons and covers it with tape or plugs the holes so he can remove and drain.Im not so sure about a hard mount for the motor id try and fit some kind of rubber mounts in there somehow.Im sure with your skill you can come up with something  ok2.
Mart
Title: Re: 1/8 scale hydroplane 'Atlas van Lines' build
Post by: Baz2 on July 17, 2009, 01:33:14 PM
 
   Hi Ramon
       
         I am new to model boats so decided to join the forum to learn from other members building experiences.

         I was impressed with the parts you cut out from the ply, I would be interested to know if you used a bandsaw
         or a good old fashioned modelling knife.

         The boat looks great, keep up the good work, I shall follow build with interest.

        Baz2
Title: Re: 1/8 scale hydroplane 'Atlas van Lines' build
Post by: ids987 on July 17, 2009, 02:25:30 PM
Hi Ramon,

Truly a joy to behold. If I ever managed to build anything that well (and I never will. I haven't got the skill, patience, time.... the list goes on), I don't think I'd want to run it, and I get most of my kicks from the running. The little touches and forethought speak volumes too.

I hate to say it, but I would personally prefer to see rubber mountings as well though - were it me.
Without, I think noise, and the vibration itself will be problematic. If the noise isn't a problem, I think vibration will be - even if not immediately.
The threaded rubbers come in quite a variety of lengths. Even the shortest should be better than none. Vertical rubbers could perhaps save space in the horizontal plane. I have also seen riggers, where rubber grommets or blocks of some kind are inserted in the sides of the tub, and bolts pass through these to the engine mounts. I think that system is used on at least some of the Eagle SG family.

Must admit, with normal rotation, I always thought offset to the right was the way to go for torque counter-reaction, but I guess there are a few factors at play, and may be different in a Hydro. The most common argument for right of centre offset, seems to be that there is then more boat to lift left of the engine, than right of the engine. Having sponsons, and the right hand sponson (presumably) having water to push down on, may change this though. Obviously the balance point also moves left with the engine. Turn fins also generate lift (sorry, stating the obvious again). Riggers with large turn fins (especially if they are not very sharp), can tend to lift the right hand sponson at speed - even against the torque. Am I getting warm anywhere in there ?

Ian
Title: Re: 1/8 scale hydroplane 'Atlas van Lines' build
Post by: andyn on July 17, 2009, 02:55:26 PM
All the current Eagle SGX's and I think all the Firefighters have the rubbers going out through the side of the tub :-))

Straight mounting an engine, especially one as big as that, will create so much noise and it will shake joints apart. I've been there done that with a small catamaran...
Title: Re: 1/8 scale hydroplane 'Atlas van Lines' build
Post by: Ramon on July 17, 2009, 06:16:15 PM
Hi All
So pleased to receive this valued input - I am taking it all on board and will reply to it all later
In the meantime, really, a big thanks.
Ramon
Title: Re: 1/8 scale hydroplane 'Atlas van Lines' build
Post by: Ramon on July 17, 2009, 10:28:31 PM
Hi guys, back again but with a bit more time to respond to your thoughts.

First though - Baz - All the parts are cut using a small Burgess BK3 bench mounted bandsaw. I don't know if they are still made (mine's twenty five years old!) but I'm sure there must be something very similar and probably now much cheaper though this one was not that expensive. I have a twentyfour teeth per inch metal-cutting blade mounted all the time. I find this ideal for cutting the wood sizes mainly dealt with and it will handle quite thick chunks of metal too if you take it slowly. I always cut just outside of the line and finish with home made sanding blocks. I do have a linisher but rarely use it. The blocks are easily made using Contiboard off cuts and double sided sticky tape and 60 to 80 grit for roughing and finer grit down to 320 for finishing. I have built up a collection of sizes and grits over the years, always reluctant to bin them some are very well worn but still have a use. You can 'sand' very smooth straight edges with longer versions :-
(http://lh4.ggpht.com/_XuA0NMLYOxg/SmDejJcTQ2I/AAAAAAAACSA/9svNYwO2aEw/s512/DSCN1570.JPG)

Regarding the engine mounts - Hmmm! I take on board all that you say and admit that it looks as if my thinking on this is abit out of kilter with current thinking. I have mounted the HP60 in the Huntsman on rubber supported ally mounts but as said felt I didn't have enough room. Having taken a good look today I think in hindsight with a centrally mounted motor I could have done. I don't think that it would be a viable proposition at this stage to try to change it - too much cutting involved - so will leave it to see how it works out. Though it appears that noise is not too great an issue where this will be driven I am concerned by Andy's comment - this side of things I didn't consider at all. Resonnance from vibration can be a real problem though. The manner of mounting is exactly how I mounted motors in my aircraft where vibration, or rather lack of, is just as important but as said before those motors were running at a much lower rev bands. However I would say that most of the time hard mounting dissipated any vibration through the airframe much better than those aircraft with motors resilient mounted.
I'm afraid my decision to do this is based on previous experience and obviously not current practice. It will be interesting to compare the two boats over this matter and I'll let you know how this turns out.
As a matter of interest do boats have a decibel rating they are expected to comply with as aircraft certainly do. How do you measure it with boats? ie with aircraft it is from all four points 3ft off the ground at 7mtrs distance.
Andy can you explain a little more descriptively about the 'mounting through the side of the tub' please I would be interested to see how this is done.

Ian, as always thanks for another in depth reply. Again I think I have looked at this from an aircraft perspective - to counteract torque the side thrust is normally set to the left. I can see what you are saying, but I have assumed that having the greater mass to the right of the engine will mean the torque has more to push against. Boats at Bungay are required to run clockwise so 'right hand' all the time which in itself applies this right hand pressure. I'm not so sure of my reasoning now thats for sure but again only time will tell on this one too.

It will be interesting indeed to see if this ole man's thinking can still cut the biscuit but by the sound of it I doubt it!

Progress is ongoing the first top skin was glued on this evening can't wait to get the clamps off tommorow

Thanks again you 'lovely lads'

Regards - Ramon








Title: Re: 1/8 scale hydroplane 'Atlas van Lines' build
Post by: martno1fan on July 17, 2009, 10:49:32 PM
Ramon sound level is measured in decables and the law says 82 is the limit i believe?.I really hope you do add rubber dampers to your setup its not that hard to do,use ali angle bolted to an ali plate to mount your motor to then add the dampers between the ali angles and the wooden rails.Vibration in a boat will quickly loosen every nut and bolt and also pull joints apart at the speeds this thing will be doing.As regards planes and boats air is soft water is hard ,vibration in a boat is magnified trust me.
Mart
Title: Re: 1/8 scale hydroplane 'Atlas van Lines' build
Post by: andyn on July 17, 2009, 11:30:57 PM
The limit for both OMRA and MPBA is 80 decibels, this is done by the sound meter being at 90 dergrees to the running boat on a straight, at 10 meters distance.

I've had a wooden catamaran powered by a .16 (that I didn't make by the way) that shook all the glue joints apart. Ive also seen a Perkasa powered by .35 sports engine that actually took the mountings and propshaft out of the boat.

Look down the side of this hull, next to the engine you will see two blue bolt heads. These are the ends of the rubber mounts. The engine itself is mounted on two right angled rails, which are bolted to the other size of those rubbers. This is very common practise in Outriggers, in fact I think just about every wooden hull uses this method. Carbon ones are done differently.

(http://i288.photobucket.com/albums/ll184/andyn_01/Jap-pinkish.jpg)
Title: Re: 1/8 scale hydroplane 'Atlas van Lines' build
Post by: martno1fan on July 18, 2009, 12:04:14 AM
cpl more examples last ones mine in the  first comet t boat
Title: Re: 1/8 scale hydroplane 'Atlas van Lines' build
Post by: Ramon on July 18, 2009, 10:57:22 AM
Excellent, thanks Andy and Mart I can see exactly what you mean. I have to admit it could have been one this way.

Just been out and took those clamps off - very pleased. Had another good look to see if I could do what you suggest but it really would involve such a high degree of 'intrusion' that I don't really want to try at this stage.
I shall have to live with it now but will not go this way again. Just hope the noise is acceptable.

I'll try to get a further posting on the build tonight.

Regards for now and thanks again - Ramon
Title: Re: 1/8 scale hydroplane 'Atlas van Lines' build
Post by: andyn on July 18, 2009, 02:28:37 PM
The rubber mounts (small type) are 6/8" diameter, could you not drill 7/8" holes through the ply itself and contain the rubbers within the wood, bolting them to an ally plate on the other side of the ply. Something like this:

(http://i288.photobucket.com/albums/ll184/andyn_01/drawing.jpg)
Title: Re: 1/8 scale hydroplane 'Atlas van Lines' build
Post by: Baz2 on July 18, 2009, 03:51:26 PM

   Hi Ramon

     Thanks very much for the prompt reply and the information which is very useful
        Thanks once again
 
                  Baz2
 
Title: Re: 1/8 scale hydroplane 'Atlas van Lines' build
Post by: martno1fan on July 18, 2009, 05:09:23 PM
Ramon this would be how i would do it.4 bits of ali angle and 4 rubber feet and an ali plate to mount your motor onto.
Title: Re: 1/8 scale hydroplane 'Atlas van Lines' build
Post by: andyn on July 18, 2009, 09:05:22 PM
The bottom of the crankcase looks a little too close to the hull bottom to be able to do that I think.
Title: Re: 1/8 scale hydroplane 'Atlas van Lines' build
Post by: martno1fan on July 18, 2009, 09:32:21 PM
Even if thats the case he can flip them the other way up so the motor is hanging from them either way works.Thats what i had to do in my Rocket hydro i flipped one set to get her lower.Id also consider usaing a flexable cable instead of a solid shaft that way he has more options as regards motor posistion .
Mart
Title: Re: 1/8 scale hydroplane 'Atlas van Lines' build
Post by: andyn on July 18, 2009, 09:55:53 PM
Also If you used a strut or a stinger (preferable) you can alter the thrust angle of the engine. However the plans do detail a flexi shaft, I think the tube in the pic is the stuffing tube, I'm sure Ramon will enlighten us on this :-))
Title: Re: 1/8 scale hydroplane 'Atlas van Lines' build
Post by: Ramon on July 18, 2009, 10:27:21 PM
Hi guys,
I have to say I can't get over your interest in helping me here, your effort on my behalf Andy and Mart and Ian is much appreciated.  :-))
I have read all you've said several times but have to say it's really a bit too late in the day on this boat to do what you recommend. You may be misled by the pics of it above but remember these are retrospective and the boat is a lot more advanced than they show. Please - don't take this as I'm not listening, I am, but I really don't think I can take up your advice on this one as it now stands without doing some severe cutting about. Here's a few pics of the installation as of tonight - I'm sure you will see the dilemma.

(http://lh5.ggpht.com/_XuA0NMLYOxg/SmIzvxhnU2I/AAAAAAAACS0/eFAutsy7DSI/s512/DSCN1576.JPG)

(http://lh4.ggpht.com/_XuA0NMLYOxg/SmIzwUukMzI/AAAAAAAACS4/10ITPJBSXL4/s512/DSCN1577.JPG)

(http://lh4.ggpht.com/_XuA0NMLYOxg/SmIzxOptUOI/AAAAAAAACS8/2lMkDWatPG0/s512/DSCN1578.JPG)

(http://lh3.ggpht.com/_XuA0NMLYOxg/SmIzx4QRYlI/AAAAAAAACTA/rAxozRfqEHg/s512/DSCN1579.JPG)
The fuel tanks are within 1/2" or so of the rail outside face each side and the top skin on the left is now very firmly glued down making access very difficult. All the parts are bonded with epoxy.
No, I guess I'm stuck with this as it stands {:-{ and can only say that whilst I take onboard everything you are saying my previous boats did have hard mounted  engines and can only reiterate that I really don't remember any real stress problems due to vibration. That does not mean I don't think I won't this time merely that's how I remember it. That original OPS 60 was mounted to an ally plate bolted in turn to beech bearers that were bonded to the F.G hull.

I will pay very close attention to engine /shaft alignment (It is going to be a flex shaft by the way - it's just pushed into a temp coupling there to hold the flywheel on to get the slot in the hull aligned) and balance everything I can (new flywheel for a start!).
I do appreciate your advice, my main concern now is your reference to noise but can only wait and see on that one. One thing's for sure my next one (and yes there will be a next one!) will not be built like this.

Hope you can see my situation

Thanks again - Ramon
Title: Re: 1/8 scale hydroplane 'Atlas van Lines' build
Post by: andyn on July 18, 2009, 10:49:55 PM
I have to say I can't get over your interest in helping me here, your effort on my behalf Andy and Mart and Ian is much appreciated.  :-))

We just want to see it goooooooooo......
 :-))
Title: Re: 1/8 scale hydroplane 'Atlas van Lines' build
Post by: martno1fan on July 18, 2009, 11:03:42 PM
No worries Ramon so will this be a transom mounted strut setup or true scale and have the prop under the hull ?Will it be angled down or parallel like a surface drive setup.Im asuming like atraditional submerged setup? in which case a solid shaft would be best because a flex needs the bend to avoid cable whip.Excuse my questions as i havent seen the plans yet lol.by the way Andy you cant use a stinger on a hydro as the prop sits too low under the transom  ;).
Mart
Title: Re: 1/8 scale hydroplane 'Atlas van Lines' build
Post by: andyn on July 19, 2009, 01:20:48 PM
Andy you cant use a stinger on a hydro as the prop sits too low under the transom  ;)

Ok then :-)) Not a Hydro man myself, just prefer stingers to struts O0
Title: Re: 1/8 scale hydroplane 'Atlas van Lines' build
Post by: martno1fan on July 19, 2009, 04:38:43 PM
Yea stinger drives are ok for easy adjusting but from what im told the strut is still the best for speed  ok2.That said the extended type are suposed to be very good compaired to the standard ones.
Mart
Title: Re: 1/8 scale hydroplane 'Atlas van Lines' build
Post by: Ramon on July 20, 2009, 10:37:23 PM
Hi  again guys, finally found a bit of time to put on a further update.

Following on the lower sponson skinning was finished off before turning it back on the jig and taking stock of the insides. Lots of clamps need for this as well as weights as you can see but it all went well. Glue used is Titebond 3 - this has been used for the entire build except the engine area. Excellent glue, very quick grab time, but not easy to sand.

(http://lh6.ggpht.com/_XuA0NMLYOxg/SjwKZyM-zfI/AAAAAAAACIk/B0GudJYgiE8/s512/DSCN1301.JPG)

(http://lh5.ggpht.com/_XuA0NMLYOxg/SjwKaUc34vI/AAAAAAAACIo/qUlUs7N0OOg/s512/DSCN1302.JPG)

Back on the jig it was time to establish the fuel tanks and radio gear. The tanks are made from SWMBO'S hair 'stuff' aerosols. Marked 200ml they actually hold 250ml each. I got the caps off using a crude cutter piercing the top in stages. I had previously tried prising it off but this left the top distorted and flimsy. A couple of ally caps were turned and fitted with brass nipples. The feed system is the R/H tank is pressure fed from the exhaust, clunk weight in R/H side feeding to the L/H tank then clunk weight pick up for the engine feed. This was based on info gleaned off the forum and the guys at the lake. My main concern was that tanks from tinplate may rust on the inside and though I have made countless tanks over the years for aircraft have never had this problem. However I have had - despite intense cleaning methods - residue of flux turn to wax like deposits that will clog the needle valve with annoying ease. Thing was those tanks were easily removed to sort the problem out and these weren't going to be hence the choice of 'drawn ally' aerosols. These 250ml were the largest I could get in the available space so how long an OPS-60 at full chat will last on half a litre remains to be seen. 

(http://lh6.ggpht.com/_XuA0NMLYOxg/SjwKfx_aK8I/AAAAAAAACJI/gNYflP2H7pg/s512/DSCN1310.JPG)

(http://lh5.ggpht.com/_XuA0NMLYOxg/SlUIvIfPj2I/AAAAAAAACNk/bLDP4mD_KT4/s512/DSCN1533.JPG)

(http://lh5.ggpht.com/_XuA0NMLYOxg/SlUIvsT5hTI/AAAAAAAACNo/kVFG5N4dZCg/s512/DSCN1537.JPG)

The ally caps are glued on using 'JB Weld' and the tanks are held at this point, supported in the middle by a band of insulating tape and 1/32 ply and at the rear by a button of 'silicone' May be a bit overkill but they're in there for the duration so wanted to be sure. At first the tanks were going to be totally 'buried' but I have decided to make small hatches over the front ends to access the nipples so these at least can be 'got at' for cleaning if neccessary.

The radio gear sits in front of the engine - weight in front of the C/G - with the rudder servo remote in another box aft, the servo lead running through the black tube seen on the earlier pics.
This was done as an effort to reduce the weight at the rear and to give a short and rigid pushrod to the rudder.

A little bit more then a bit later!

Mart - it is going to have transom mounted strut but with the prop close in - about 11/4" overhang. This is how the drawing is set up. However - having followed a lengthy discussion on this matter on R/C Universe provision has been made to retro mount the strut brackets inside the strut coming through the bottom skin. This would give a submerged drive with the prop position just under the transom.

I can still use the flex shaft for both - obviousy I will have to shorten it but the angles involved look very close to each other. Remember chaps I have no idea how these thoughts will pan out this side of things is my steep learning curve but I am going to enjoy myself doing it - Andy, You can't wait to see it goooo have a guess how I feel.

Ian, I notice I made a complete boo boo :embarrassed:
Quote
Again I think I have looked at this from an aircraft perspective - to counteract torque the side thrust is normally set to the left.
I did mean the aircraft turns left with torque - side thrust to the right - dyslexic brain again

Bye for now - Ramon

BTW I have not forsaken the Huntsman. It's just that the weather has not been suitable for spraying enabling me to make quite a bit of progress on this one :-))
Title: Re: 1/8 scale hydroplane 'Atlas van Lines' build
Post by: ids987 on July 23, 2009, 03:29:30 PM

Ian, I notice I made a complete boo boo :embarrassed:I did mean the aircraft turns left with torque - side thrust to the right - dyslexic brain again

Hi Ramon, Maybe you could think of it as an aircraft with a pusher prop  :}


These 250ml were the largest I could get in the available space so how long an OPS-60 at full chat will last on half a litre remains to be seen. 

I'm thinking 5 - 10 minutes ballpark.....

Ian
Title: Re: 1/8 scale hydroplane 'Atlas van Lines' build
Post by: Ramon on July 23, 2009, 04:26:11 PM
Really - REALLY ? is that each bottle?? Hell I've lead a sheltered life - my OS 35 aerobatic models would do a seven minute flight on 90cc and that was running rich!!!! {-)

Seriously I didn't expect much - I can't remember how big a tank I used all those years ago but it was home made. Memory says (hmmmm?) it lasted a lot longer so must have been quite a bit larger. I was only using the X type Graupner props in those days - guess the revs are much higher now eh?

That said at this stage I am only intending to get the best out of this on straight running - just seeing it go will be buzz enough.

Thanks Ian - should have thought of the pusher - nice one

Ramon
Title: Re: 1/8 scale hydroplane 'Atlas van Lines' build
Post by: andyn on July 23, 2009, 04:52:07 PM
Yep I'm afraid so, mind you at least you don't run multi's, in three quarters of an hour a 3.5cc will drink 1.5 litres, a 7.5cc will drink 2.5 litres, and a 15cc will drink 3.5 litres. thats about £20 a race for a 15...
Title: Re: 1/8 scale hydroplane 'Atlas van Lines' build
Post by: ids987 on July 23, 2009, 05:06:11 PM
Really - REALLY ? is that each bottle?? Hell I've lead a sheltered life - my OS 35 aerobatic models would do a seven minute flight on 90cc and that was running rich!!!! {-)

Hi Ramon, My CMB 45 uses at least 2 litres in 1/2 hour. I think the OPS 60 should burn slightly less, but not that much less.
I seem to remember that my old OPS 60 used to go about 20 minutes on 1 litre. That was in a mono, but before I found a pipe that worked properly with it. RPM and load make a difference. Pipe pressure tends to waste a bit of fuel - unless you use an interim tank for the pressure, as it can atomise fuel out of the tank and blow it out of the exhaust, but sometimes it's needed. Nitro makes a difference. More nitro = richer mixture.
Title: Re: 1/8 scale hydroplane 'Atlas van Lines' build
Post by: Ramon on July 23, 2009, 11:40:15 PM
Well that's it then - back to rubber power free flight models it is !!!!!!!!!! ok2

No, not really but I can see this is going to use a lot more fuel 'per go' than I've been used to up to now!

Quote
..........unless you use an interim tank for the pressure, as it can atomise fuel out of the tank ...............

Would you mind explaining this a bit more in depth Ian please. Pressure fed fuel is a new method of fuel feed to me - I never had much success with it with the type of aircraft I flew but the engines had good suction with relatively much smaller venturi's so very rarely required it.

Following on from my last post on the fuel tanks themselves and Mart's comment about using  ally 'drinks containers' - I have had an email from someone following the thread to say that a friend of his had had touble with the fuel reacting with the ally and causing gumming up resulting in damaging a K&B 67. I replied that I thought it might be a coating that may be applied being disolved by the nitro. Just a thought. Yesterday I saw one of these bottles for the first time and and confirm that that it did have such a coating. I did check the aerosols leaving 5% fuel in them for some time as well as cellulose thinners neither seeming to have any effect but I do think if these (drinks cans) are used this is a warning that should be given due consideration.


Here are another few pics bringing the build closer to its current status

(http://lh5.ggpht.com/_XuA0NMLYOxg/SlUIx5LEN9I/AAAAAAAACN0/Q7nF4YeyV8A/s512/DSCN1541.JPG)

(http://lh3.ggpht.com/_XuA0NMLYOxg/SlUIwaRIVDI/AAAAAAAACNs/qK0yCK2Xwuk/s512/DSCN1538.JPG)
These shows the front end and rear radio gear box positions. The central ply plate at the front is removeable. I intend to bolt lead weights to this as a trimming aid if the C/G needs to be adjusted.

(http://lh4.ggpht.com/_XuA0NMLYOxg/SkfeSxItvSI/AAAAAAAACLc/0J8t_zoEFo0/s512/DSCN1529.JPG)
Here is the set up at the stern. The strut brackets will be shortened (to the line just visible) and redrilled, the ply plate insert is reinforcing if it's decided to later mount the strut from underneath

(http://lh4.ggpht.com/_XuA0NMLYOxg/SlzvS4lYL3I/AAAAAAAACQA/_MIaGZSaWcc/s512/DSCN1551.JPG)
All the stringers are in place and the insides epoxy coated. The blue foam is from Marts idea of using 'pool noodles'. It's near ready for those top skins.

That's it for tonight - thanks as always for your input - Ramon


Title: Re: 1/8 scale hydroplane 'Atlas van Lines' build
Post by: mook on July 24, 2009, 11:04:03 AM
I'm loving this build     O0   ;D
Title: Re: 1/8 scale hydroplane 'Atlas van Lines' build
Post by: andyn on July 24, 2009, 01:12:41 PM
Pressure feeding is basically using the pressure from the pipe to pressurise the fuel tanks. This keeps the flow going to the engine. To do it with your tanks, you would have to take the pressure pipe via silicon tubing to the top tube on one of the tanks, then the lower on that tank to the upper on the other tank, then the lower pipe on the second tank to the engine. What I'm hoping to eventually do with my 3.5cc multi is to use a Novarossi Exhaust Cooler, which supposedly cools down the exhaust gasses travelling into the tank, which should increase run times. Might be worth a try on this thing too.

(http://www.novarossi.it/images/public/img_products/accessories/groot/36000.jpg)
Title: Re: 1/8 scale hydroplane 'Atlas van Lines' build
Post by: ids987 on July 24, 2009, 01:31:24 PM
Pressure feeding is basically using the pressure from the pipe to pressurise the fuel tanks. This keeps the flow going to the engine. To do it with your tanks, you would have to take the pressure pipe via silicon tubing to the top tube on one of the tanks, then the lower on that tank to the upper on the other tank, then the lower pipe on the second tank to the engine.

Hi Andy, I could be wrong, but I think Ramon knows what pressure feeding is, and how it works. I think he was asking me to explain what I meant by a pressure tank.

Hi Ramon,

Following on from the scenario Andy has described, and in the case of your install, a pressure tank would be a third - small fuel tank. This tank is left empty. You connect the pressure feed from your tuned pipe (I hope you're using one ?) to the vent tube of the pressure tank. The pickup side of the pressure tank connects to the vent tube of your first tank. The idea is; when you go from full throttle to part throttle, the pressure in the tank is temporarily higher than the pressure in the exhaust. If there is fuel around the vent pipe area, it can be blown back to and out of the exhaust. Similarly with any fuel atomised from the main tank to the exhaust. With a pressure tank in between, the fuel passing backwards will just collect in the pressure tank - until the pressure pushes it back to the main tank (through the fuel pickup of the pressure tank). Hope I've explained that well enough. Let me know if not, and I'll try to do better.
My OPS 60 was a bit iffy running on suction feed alone. Coupled with the fact that you are planning to cross-feed from tank to tank, I think you will need to use pressure feed one way or the other. Of course, in a cross-feed install, the first tank becomes a pressure tank once it has emptied into the second tank......

Ian
Title: Re: 1/8 scale hydroplane 'Atlas van Lines' build
Post by: ids987 on July 24, 2009, 01:52:43 PM
Hi Ramon,

With regards to the fuel and containers, I did wonder about aluminium and nitro. If anything in the fuel is going to cause corrosion, it is usually nitro, or at least its by-product - nitric acid. It will eat through brass pickup tubes in fuel tanks - given time. Usually that is minimised by draining tanks after play.
I guess coated cans add another variable. If the coating doesn't even go "tacky" after exposure, I guess it will most likely be ok....
Title: Re: 1/8 scale hydroplane 'Atlas van Lines' build
Post by: Ramon on July 24, 2009, 10:49:27 PM
Hi  Ian - yes got that and can see exactly what you are saying. :-)) I don't suppose this 'chamber' has to be too big so will fit something in the system. This is a new concept to me - the pressure feed I have 'dabbled' with unsuccessfully in the past was in search of obtaining a good consistent engine run throughout a flight. It is accepted that the key to a good aerobatic model is the need for a motor that is totally consistent. This is not top end performance - most engines (all glow two stroke that is) were run on the ground just off the 'break' into the 'two stoke' rev band. (Technically incorrect the rich running with the needle out from it's max setting was always referred to as four stroking.)  Hence the term [good 'four-two' run] characteristics of some engines.
Tanks played an important part in trying to obtain this consistancy and most were run on a 'uniflow' basis. Some (including myself) did  try to 'improve' this using pressure but without much success. Very much a 'horses for courses' situation. My first experience of pressure feed goes back to Army days! - 1967 when I bought in Singapore a Super Tigre G15 'speed' motor - enormous venturi fitted with a plastic insert for suction feed - but even with this it would only run using pressure.
The engine will have a tuned pipe though regretably not an OPS original. I was recently given a 60 size pipe by someone who was a keen R/C aerobatic flyer (BIG difference from control line I might add) Whether this pipe will be suitable to get the best from the engine I don't know but at this early stage it will have to act as simple 'exhaust chamber' at the least. Perhaps when the boat is up and running I will search out something more suitable if it proves otherwise.
Couple of pics here, perhaps you would cast your eye over them and tell me what you think. The red lines show positions of three baffles. (You cannot see through the pipe end to end).
(http://lh3.ggpht.com/_XuA0NMLYOxg/SYDDx7-jabI/AAAAAAAABcU/YHzYkBAb_vg/s512/DSCN1275.JPG)
(http://lh5.ggpht.com/_XuA0NMLYOxg/SYDD020hO8I/AAAAAAAABck/WYZJkX2uhjI/s512/DSCN1277.JPG)

That nitro is corrosive is without a doubt but I was always under the impression that the acid (nitric) is as a result of the combustion. The more I think about this the more - when you consider the mount of ally that comes into contact with the fuel in most setups - pipework?, filters, engine itself - that I would think the real culprit in this gumming up is something like the coating
reacting/dissolving as already said. It's very unlikely that I shall use anything more than 5% - 10 at the very most.

Thanks again Ian and for your help too Andy it's all grist etc.
Glad you are enjoying it Mook.

Regards - Ramon
Title: Re: 1/8 scale hydroplane 'Atlas van Lines' build
Post by: martno1fan on July 27, 2009, 07:01:59 PM
Ramon i thought you might like to see this  :-)).
Mart
http://vimeo.com/4157234 (http://vimeo.com/4157234)

http://vimeo.com/4156979 (http://vimeo.com/4156979)
Title: Re: 1/8 scale hydroplane 'Atlas van Lines' build
Post by: Ramon on July 27, 2009, 07:58:05 PM
Ah Mart, you really are a wind up merchant!!  ;)

Just tried again to download Flash Player again but still to no avail  {:-{- I get right through the installation process until it says - if installation is successful you can see the video above (or something very similar to that ) No video! just two white squares with the small red crosses in them.  Tried the trouble shooting and followed that through but still can't get these files to open - just keeps telling me to install Flash Player! So - I still can't watch it - Dammmmm! Keep it on hold for me - I'm just going to have to get this bl---y thing fixed!!!!

Got the rear hatch done today and the fins mounted - it's getting there. The weather looks abysmal for painting the Huntsman for the next few days so I'll stick with the hydro - at this rate it'll be finished first.

Any comments on that tuned pipe I've been given anyone - is it going to be suitable? What effect will the long parallel part have?

Regards for now - Ramon
Title: Re: 1/8 scale hydroplane 'Atlas van Lines' build
Post by: martno1fan on July 28, 2009, 12:41:57 PM
OOPS forgot you couldn't watch these links  %),might have to do you another dvd sometime lol.Sorry i cant help with the pipe thing im not a nitro guy to be honest.Im hoping to get some hardware installed onto my hydro soon and then ill swap the motor from the wooden zipp and try it in her to see how she compairs.I have a few hulls to build before that so it might take me a few weeks till shes ready.
Mart
Title: Re: 1/8 scale hydroplane 'Atlas van Lines' build
Post by: ids987 on July 28, 2009, 04:47:09 PM
Hi Ramon,

Sorry, haven't had the opportunity to write on here for a few days.

I think you are right - in that (at least in our applications), nitric acid will only be liberated in significant quantities under combustion.
I have definitely experienced more than one fuel tank though - where the brass fuel pickup has corroded to the extent that it pulls up more air than fuel. Not sure whether that is the corrosive effect of the nitro itself, or the nitric acid passed back via the pressure feed. I would agree that this probably has little to do with the gumming up though.

With regards to the Hattori type pipes. Are those the ones where the end of the divergent cone is closed by a flat disc - with the stinger in the middle - rather than a convergent cone ?
I haven't used that kind of pipe myself, but I believe they work. I suspect they would be more peaky than conventional pipes, and therefore possibly unusable on engines with very high timing. The OPS is milder than a lot of modern engines though, so it may be ok. The OPS pipes themselves work ok, but are not the bee all and end all, and even the OPS "quiet" pipes are not at all quiet by todays standards. Here again though, the OPS engines probably have a bit less tendency to noise generation than some.

Pressure feed in boats was also (I think), introduced to try and aid in getting a consistent mixture and running. In some situations, it does help to give a more consistent top end mixture than suction feed, but can make throttling problematic. It seems to be carb dependent, and probably on how quickly the pressure falls off after closing the throttle. But hey, hydros aren't meant to go slow are they ?
In the world of multi racing now, almost everyone who wants to be competitive runs a float chamber. Don't think I've ever heard of one in a hydro though.

Keep it coming !

Ian








Title: Re: 1/8 scale hydroplane 'Atlas van Lines' build
Post by: ids987 on July 30, 2009, 06:13:04 PM
Hi Ramon,

Sorry, thought I'd better post back as I appear to have been talking rubbish in my last post. I also failed to read / interpret your questions properly.
I think it's fairly evident that the pipe in the photo is not the kind of pipe I was thinking of.

I'm pretty sure that the pipe itself will be a conventional dual cone type of pipe. The long parallel section is mostly silencer. The plates you have marked are silencer baffle plates behind the end of the pipe itself. Kind of like this (c/o Dave Marles / Prestwich) - except that your silencer section is wider, and extends from the join between the divergent and convergent cones:

(http://img124.imageshack.us/img124/9943/74128170.gif) (http://www.postimage.org/)

(http://img125.imageshack.us/img125/8100/75241257.gif) (http://www.postimage.org/)

The front / divergent cone of the pipe appears to be quite long, so it is likely to be best suited to an engine with relatively mild timing (an engine with shortish exhaust -> transfer blowdown period - favouring torque / reliability over out and out power / RPM). Very much what you would want from an engine / pipe combination in an aerobatic model - not that I know much about those. It probably won't get the very best out of the OPS, but it should work to some extent. The perforated plate silencers can work quite well, but it depends on the implementation. If the holes (or the total area of the holes) are / is too small (and I have seen / owned some which are), and the pipe presents too much back pressure, much of the function of the pipe will be dictated by the silencer.

Ian
Title: Re: 1/8 scale hydroplane 'Atlas van Lines' build
Post by: ids987 on July 30, 2009, 06:22:34 PM
Duplicate post...
Title: Re: 1/8 scale hydroplane 'Atlas van Lines' build
Post by: Ramon on July 30, 2009, 09:13:03 PM
Ian, - just seen your posts - again many thanks, will digest and come back to you a bit later

Ramon
Title: Re: 1/8 scale hydroplane 'Atlas van Lines' build
Post by: Ramon on July 30, 2009, 11:11:32 PM
Hi again,
Not sure where to begin here Ian, my knowledge of pipes is so limited. Beyond the basic working principle it's all so much a mystery. It seeems to me that the variables are so great - timing - nitro - torque band - revs - etc etc it's difficult to even comprehend where to begin!

However let's take the pipe in question. Sorry I can't provide a sketch but I'll do my best to describe it :-

Looking in the inlet end there is no convergent cone but a flat plate baffle with a central hole about 1/2" diam. Beyond that is another flat baffle with an offset hole that has a tube - as far as I can tell about an inch long - pushed through it. That's as far as can be seen from that end. From the outlet end again another flat baffle with another offset hole and another piece of tube this time about 1-1/2" long. The divergent and convergent cones are separated by a parallel tube approx 6-1/2" long with the first baffle positioned approx 3" past the limit of the divergent cone and the distance between the two outer baffles about 2"

I think I understand what you are saying regarding timing - the aerobatic engine would definitely be more set up for max torque at lower rev banding so from that I think that it's unlikely this pipe will act as little more than an expansion chamber.

As said this was donated by a well meaning friend and at this stage will have to suffice in the short term until something more suitable can be obtained (especially as I've just milled a posy clamp to hold it on with!) However if anyone out there reading this has a redundant OPS60 pipe or something simarly suitable lurking under the bench that they would consider parting with I would be most pleased to hear from them.

Not much done on the boat though the fins are now finished and fixed - having a couple of days getting the metal work sorted and a short break on bits for rebuilding that other OPS.

Thanks for your time again Ian
Back soon
Regards - Ramon

Title: Re: 1/8 scale hydroplane 'Atlas van Lines' build
Post by: ids987 on July 31, 2009, 02:31:50 PM
Hi Ramon,

Aahhh, my initial guess/assumption about the pipe design was actually correct.
The flat plate with the 1/2" hole in the middle functionally replaces the convergent cone. Everything behind that is basically the silencer. The convergent cone which you see is the end of the silencer section. It does not function in the same way as the convergent cone in a conventional tuned pipe.
The long front cone still suggests the same thing as in my last post (as does the intended application of the pipe) - that it is designed for use with a relatively mildly timed engine - which will tend to have a broad power band.
Going back to the other end of the pipe, the convergent cone in a conventional pipe acts as a reflector - reflecting the pressure wave back towards the engine. As it reflects the wave from different points along the cone, it tends to "blur" the arrival of the pressure wave back at the engine - spreading it over a longer duration. This, in turn, has the effect of broadening the powerband slightly. Replacing the cone with a flat plate, will tend to strengthen, but concentrate the reflected wave - giving a bit more of a kick when the pipe comes in, but across a narrower powerband. As our example "mild" engine will generally not come on pipe very hard, this may well give it a bit of a useful boost.
I won't waffle any more on my theories as to why (unless you want me to), but on the whole, I don't think the engine and pipe combination will have the best synergy, but there is always an element of "suck it and see" in tuned pipe selection.
The silencer section sounds fairly conventional. The pipes you described - linking the expansion chambers, may either be open ended, or closed at the end with radial perforations along the length. Either way, the functional model is not too dissimilar to the perforated plate example in the photo I posted. The main objective is to lose as much of the sonic energy as possible - by allowing the gas to expand, breaking the direct (straight through) path, and making it change direction several times - without posing too much resistance to the actual throughflow of the gases. I suspect that it will be substantially quieter than a good few pipes I've seen / owned / still own.

Ian
Title: Re: 1/8 scale hydroplane 'Atlas van Lines' build
Post by: Ramon on August 01, 2009, 08:26:49 PM
Well Ian, just goes to prove you learn something every day. I would never have considered that the baffle would act as the convergent cone.

Thanks for your PM but (typically for me) replied in the wong manner so had it sent back today.  :embarrassed:
Sent you another tonight so hope you get that ok.

Still waiting for a decent break in the weather to get some paint on the Huntsman so have continued making parts for the OPS. Nearly there on that so will update the thread in a day or so.

Thanks for taking the time to explain things again. I for one wouldn't mind some expansion on the subject - I don't feel that that would be exactly off topic just a slight, albeit relevant, digression.
I think I understand the principle and also think I can see how the wave lengths attune to a certain point in the rev band but how do you know where and when? How do you choose a pipe for instance other than eg 60-90 size. Wouldn't this have to be more specific to an engines performance rather than capacity? Aaagh! so many questions for this well worn brain to cope with. %%

Regards - Ramon
Title: Re: 1/8 scale hydroplane 'Atlas van Lines' build
Post by: Ramon on August 02, 2009, 11:28:51 PM
Hi guys, Not much to report on the hydro but as I was tinkering with the OPS bits today I was musing - as you do - on past posts regarding pressure feed.

Ian, your comment
Quote
In the world of multi racing now, almost everyone who wants to be competitive runs a float chamber.

If the float chamber works as I imagine - exhaust pressurises fuel tank, chamber fills up, float rises and momentarilly cuts off supply, engine draws fuel, float drops then cycle repeats - Surely the pressure on the fuel is cut off from the engine by the float chamber. If this is the case is not the engine then working on suction? or does the F/Ch act as as kind of pressure regulator ''allowing a bit of pressure through'' each time. With the large bores of the carbs on these type of engines I would have thought that suction feed alone would be difficult to maintain.

Just a thought - ??????????         

Regards - Ramon                         
Title: Re: 1/8 scale hydroplane 'Atlas van Lines' build
Post by: andyn on August 03, 2009, 11:55:47 AM
The main fuel tank is pressurised from the exhaust and this forces fuel into the float chamber. When the fuel reaches a preset height, the float valve maintains that fuel height until the main fuel tank is empty.

Float chambers are great, there's nothing to go wrong in them %)
Title: Re: 1/8 scale hydroplane 'Atlas van Lines' build
Post by: ids987 on August 04, 2009, 12:44:37 PM
Hi guys, Not much to report on the hydro but as I was tinkering with the OPS bits today I was musing - as you do - on past posts regarding pressure feed.

Ian, your comment
If the float chamber works as I imagine - exhaust pressurises fuel tank, chamber fills up, float rises and momentarilly cuts off supply, engine draws fuel, float drops then cycle repeats - Surely the pressure on the fuel is cut off from the engine by the float chamber. If this is the case is not the engine then working on suction? or does the F/Ch act as as kind of pressure regulator ''allowing a bit of pressure through'' each time. With the large bores of the carbs on these type of engines I would have thought that suction feed alone would be difficult to maintain.

Just a thought - ??????????         

Regards - Ramon 
                        

Hi Ramon,

That is exactly what it does. usually you set the height so that the fuel is about level with the spraybar - what you might call a neutral position. The main point is that it gives a consistent mixture. Because it changes very little, you adjust the needle accordingly. Without a float chamber, there is a tendency to run rich in parts of the course - and lean in others. Add to that the overall level change from full to empty. You then have to try and set the mixture so that it never goes lean - meaning that it spends a lot of the time running rich. Smaller tanks will not be as susceptible to this, but with big tanks, it is a real problem. Both the moving mass of fuel, and also the level change between full and empty.
More on pipes later. I'm off work this week with the kids away - up to my eyes trying to demolish and rebuild the kitchen before they get back
I'll drop you a PM a bit later as well.

Ian
Title: Re: 1/8 scale hydroplane 'Atlas van Lines' build
Post by: ids987 on August 04, 2009, 12:51:58 PM
Hi Ramon,

That is exactly what it does. usually you set the height so that the fuel is about level with the spraybar - what you might call a neutral position. The main point is that it gives a consistent mixture. Because it changes very little, you adjust the needle accordingly. Without a float chamber, there is a tendency to run rich in parts of the course - and lean in others. Add to that the overall level change from full to empty. You then have to try and set the mixture so that it never goes lean - meaning that it spends a lot of the time running rich. Smaller tanks will not be as susceptible to this, but with big tanks, it is a real problem. Both the moving mass of fuel, and also the level change between full and empty.
More on pipes later. I'm off work this week with the kids away - up to my eyes trying to demolish and rebuild the kitchen before they get back
I'll drop you a PM a bit later as well.

Float chambers are great, there's nothing to go wrong in them %)

Hmmm, The "cheap" ones which most people use don't tend to shut off against full pressure - resulting in overflow and lost fuel. I also have one where the float doesn't float straight and therefore catches on the side - meaning it doesn't always shut off.

Ian
Title: Re: 1/8 scale hydroplane 'Atlas van Lines' build
Post by: Martin [Admin] on August 04, 2009, 01:24:40 PM
I'm loving this build     O0   ;D

Well put Mook!   :-))
Title: Re: 1/8 scale hydroplane 'Atlas van Lines' build
Post by: gwa84 on August 04, 2009, 06:55:48 PM
been watching this from the start loving it cant wait to see this beast flat out on the water
Title: Re: 1/8 scale hydroplane 'Atlas van Lines' build
Post by: Ramon on August 04, 2009, 08:55:15 PM
Quote
That is exactly what it does. usually you set the height so that the fuel is about level with the spraybar - what you might call a neutral position. The main point is that it gives a consistent mixture. Because it changes very little, you adjust the needle accordingly. Without a float chamber, there is a tendency to run rich in parts of the course - and lean in others. Add to that the overall level change from full to empty. You then have to try and set the mixture so that it never goes lean - meaning that it spends a lot of the time running rich. Smaller tanks will not be as susceptible to this, but with big tanks, it is a real problem. Both the moving mass of fuel, and also the level change between full and empty.
More on pipes later. I'm off work this week with the kids away - up to my eyes trying to demolish and rebuild the kitchen before they get back
I'll drop you a PM a bit later as well.

Hi Ian, yes thought so, :-)) just couldn't see how the fuel was pressurised at the carb. Though of course I have never used one I can see that the use of a float chamber will eliminate all the changes of head of fuel in the tanks throughout the run. This is what we tried to do in aerobatics with the so called 'uniflow' set up. It gave a very consistent run no matter what attitude the aircraft was in but of course as you state the tanks were much smaller. If you have ever seen control line aerobatics though you will appreciate the rapid change of forces involved that are placed on the fuel throughout the flight.
I shall see if I can fit one in, (as well as the expansion chamber you referred to) which will also give me just a little bit more fuel capacity. I don't think I can get one very close to the carb though - unless I move the radio gear which at his stage I don't really want to consider - is there a max distance from the carb? I guess it would be back to the 'suction' issue - closer the better.

No progress today - like yourself, 'domestic interference' but at least it's been outdoors in the garden. ok2

Next stage is to jury rig a drill to be able to drill horizontally through the fins (which are angled out) for the wing bolts and to make the wing as well. Then it's all ahead on the superstructure to finish it off. Don't get too excited guys - it's got to be painted after that!!

On that topic have you or has anyone else used the thin Ripmax SP113 epoxy resin for sealing the wood before the paint is applied. I'm thinking that this may be a much better way to seal the wood.

It's nice to hear that one or two are getting some pleasure from this  :-) I don't have a digi video camera but can see that I'm going to have to get someone to record the big moment.

Regards for now - Ramon
Title: Re: 1/8 scale hydroplane 'Atlas van Lines' build
Post by: Ramon on August 04, 2009, 09:47:56 PM
Aaah, sometimes best meant intentions go awry :embarrassed: -

Andy, my apologies - I didn't mean to ignore you - thanks for coming in on this float chamber point too.

It has to be said that the fact that others are enjoying it is in most part down to members like yourself only too keen to respond with help and advice.

Thanks to all of you out there - passive or participant - you make this forum what it is - BRILLIANT.

Regards - Ramon

 

Title: Re: 1/8 scale hydroplane 'Atlas van Lines' build
Post by: andyn on August 04, 2009, 09:56:47 PM
We just can't wait to see it go, the invitation to our lake will always stand :-))
Title: Re: 1/8 scale hydroplane 'Atlas van Lines' build
Post by: martno1fan on August 04, 2009, 10:20:40 PM
Ramon not sure what ripmax epoxy is but what you need is slow setting epoxy something like 3 hr epoxy so it gets chance to soak into the grain.Use a credit card to spread it on very thin then  scrape most of it off so you get thin coats,usually 3 is sufficient but remember to sand between coats to keep things smooth.If you do it this way you will have very little sanding to do to get it smooth once the 3rd coat is on and then shes ready for paint.
Mart
Title: Re: 1/8 scale hydroplane 'Atlas van Lines' build
Post by: andyn on August 04, 2009, 10:27:23 PM
Ripmax's epoxy is good, for wing skinning I believe?

Same stuff sold by East Coast Fibreglass Supplies, so I assume it's good stuff. As Martin says apply it with a credit card or similar, I use 1/64th" aluminium, works well.
Title: Re: 1/8 scale hydroplane 'Atlas van Lines' build
Post by: Ramon on August 04, 2009, 10:35:24 PM
Thanks Mart,
I believe the Ripmax SP113 epoxy is the same as the 'West (System?)' It's a very thin and fluid epoxy designed for skinning wings etc.
I used it to coat the insides of the Huntsman and the lower half of the AvL before I ran out of it. Got some on order though. Obviously this was just painted on and left but can see where you are coming from with the credit card - they have their uses besides getting rid of your cash eh?

I notice the top skins have some very bad grain 'plucks' in the surface so these will need filling first - I thought I'd use P38. I'll do as you suggest - I'm assuming you had no paint adhesion problems going on to epoxy? Did you use cellulose ?


That's it for now - back tomorrow
Ramon
Title: Re: 1/8 scale hydroplane 'Atlas van Lines' build
Post by: martno1fan on August 05, 2009, 12:29:44 AM
Ive used both cellulose paint and also acrylic over epoxy but as im not a nitro burner im not sure which if any of those is nitro proof.Obviously both will need clear coating,i usually use acrylic laquer on both types and it seems to work ok.Another cheap paint to try is plasticoat but that will also need clearing over,maybe try some with some nitro see if its fuel proof .Maybe someone else can help you more on that one,Andy ?  :-)).Regarding filling the wood grain just use a good filler ive even used wood filler,its going to be sealed in with epoxy anyway right  ok2.Or try halfords for some car body filler you can even pick it up in bulk on ebay for about 12-18 quid for a big tin,for that you usually get about 10-14 halfords size tins worth in one large tin so that works out at about 50 quid or more if you bought em seperateley lol.So you make a big saving  :-))
Mart
http://cgi.ebay.co.uk/U-POL-EASY-1-CAR-BODY-FILLER-3-5L-TIN_W0QQitemZ180317817498QQcmdZViewItemQQptZUK_Body_Shop_Supplies_Paint?hash=item29fbc78a9a&_trksid=p3286.c0.m14 (http://cgi.ebay.co.uk/U-POL-EASY-1-CAR-BODY-FILLER-3-5L-TIN_W0QQitemZ180317817498QQcmdZViewItemQQptZUK_Body_Shop_Supplies_Paint?hash=item29fbc78a9a&_trksid=p3286.c0.m14)
Title: Re: 1/8 scale hydroplane 'Atlas van Lines' build
Post by: andyn on August 05, 2009, 11:13:41 AM
You called? %)

I use JP Satin Fuel Proofer. :-))

http://www.jperkinsdistribution.co.uk/detail.php?JPNO=5527880&activepage=1&Navmain=Paints,%20Dope,%20Brushes&subcatname=Dope%20-%20Sealer%20-%20Thinners (http://www.jperkinsdistribution.co.uk/detail.php?JPNO=5527880&activepage=1&Navmain=Paints,%20Dope,%20Brushes&subcatname=Dope%20-%20Sealer%20-%20Thinners)
Title: Re: 1/8 scale hydroplane 'Atlas van Lines' build
Post by: Baz2 on August 05, 2009, 02:41:49 PM

    Hi Andyn

           How do you apply your fuel proofer, do you use a brush or an airbrush?

               Thanks

                                  Baz
Title: Re: 1/8 scale hydroplane 'Atlas van Lines' build
Post by: andyn on August 05, 2009, 02:42:44 PM
I brush it. Wouldn't want it to clog the airbrush then have to work out how to remove it...
Title: Re: 1/8 scale hydroplane 'Atlas van Lines' build
Post by: MRZIPPYXXXX on August 06, 2009, 01:23:47 AM
Hi Ramon,
I have followed your brilliant masterclass in Huntsman building, and now along with fellow club mates, following your stunning AVL build with great interest.
I hope I may be able to shed some light on SP113 having used it throughout my recent Swordsman build, heregoes - Structural Polymer Systems are based on the Isle of Wight, and have a very helpful technical guy should you wish to call him ! although in his opinion he would not reccomend 133 and favours other products in their range,
but these come in lager bottles, are even more expensive and not available at your local model shop, which in precisely why I use SP113.
The big secret to applying is to use disposable foam mini paint rollers, (B&Q it All etc - and yes I along with the cheapskates can cut them in half with a razor saw!)
you will be amazed how roller lets you mould the glass cloth around compound curves etc, I have covered a 5foot glider fuselage with a single piece of cloth pushed
around the curves by the foam roller, it stays stuck to tiny 3/16 square Swords sprayrails without lifting, making boat hulls a doddle.
I use Davids Isopon P38 car body filler under the Halfords paint with success, and also "microballoons" filler powder you mix with resin (aeromodelling trick avail modelshops).
SP can also be thinned down with Isopropyl Alcohol available from local chemists, I have used this thinned like tap water as a primer on fast electric racers
where weight is an issue!
I reccomend going throught the pain of glass clothing from a strength and more importantly, stability point of view, my Swords has been on the water for around 18 months
and the only area I did not reinforce (transom) with cloth is now starting show stress cracks? in the paint, from the bottom of the steepV feathering out up the transom. The Americans use this system throughout on their lightweight balsa 36" class scale hydros, see www.classicthunder website, this should keep you occupied for a few hours.
Also in the states they use the resin/cloth system over planked hulls on varnished Chris Crafts etc and the very fine weave of the glass disappears completely when finished leaving a high gloss burnished glass like finish, to coin the phrase of "boat trapped in an ice cube finish". Hope this may be of some help.
Regards Paul
Title: Re: 1/8 scale hydroplane 'Atlas van Lines' build
Post by: MRZIPPYXXXX on August 06, 2009, 01:24:36 AM
Further to above post just found this info the guy at SPsystems is Martin on 01983 828103 and he recommended their SP320 resin. Paul
Title: Re: 1/8 scale hydroplane 'Atlas van Lines' build
Post by: Ramon on August 06, 2009, 09:08:22 AM
Morning guys just a quick one to say thanks for your seemingly endless interest  :-)) Have 'taken it all in' Paul  :-))   :-)) - I will respond later.
Managed to get some primer on the Huntsman yesterday at last so want to get out and give it a good sanding for the next coat.
Back later - Ramon
Title: Re: 1/8 scale hydroplane 'Atlas van Lines' build
Post by: Ramon on August 06, 2009, 05:15:10 PM
Hi again guys, despite the warm and somewhat muggy weather I have managed to get the primer coats on the Huntsman on today. That is going to have to harden for a few days so it's back on the hydro O0
Thanks again for this informative input - especially the links and details on the resin Paul - it's certainly helped to see a bit more clearly ahead.

Now, where to start? .........I have applied .6oz glass cloth to quite a few aircraft in the past but have always used Ripmax 'Tufcote' fuel proofer as the resin. Main reason is the very speedy cure rate on the model - 25/30 mins coupled with the long useage rate of the mixed resin in the cup - depending on temperature can be several hours or even overnight if put in the fridge. Quite the reverse to epoxy or poly' resin. It has to be said that while it does'nt have the substance of epoxy it does live up to it's name when fully cured - very tough and resilient.
I like the idea of the foam roller technique - I have always brushed the tufcote resin through the cloth onto the bare wood ie no resin on before applying the cloth, using a very fine and soft haired 3/4" wide brush - working from a central point this spreads the cloth out as you go and is very effective. Are you putting epoxy on the model first or doing it in a similar fashion?

I don't want to combine two threads here however... the Huntsman has been finished in a 'conventional' cellulose 'model aircraft' type process but have to say I'm not really happy that this is going to stand up to the rigours of being on the water for very long.
To that end then I have previously been thinking, and can now see, that with (wooden) boat finishes it would be much better if the initial 'primer' was epoxy ie the waterproofing would be in the fibres of the wood itself, it would add strength and fill minor blemishes if scraped off in the manner suggested. With your confirmation that it will take a variety of finishes that makes it even more of a good choice and I shall certainly be finishing off the hydro in this fashion.

Regarding fuel proofer or 'clear coating' - the finish I have used in the past, and very successfully too, is a two pack resin 'floor finish' that I obtained from the paint finish company 'Morelli's'. This can be thinned with cellulose thinner, sprays very easilly without creating that sandpaper like overspray that some fuelproofers do and gives a beautiful finish which can be cut back and polished to a brilliant shine if desired. I carried out some tests when I first bought it - dries in 20 mins and did not react to 5% nitro after 30mins! Highly recommended if you have the facility to spray but I must add that this has only been used over cellulose finishes and you definitely need to wear a respirator as a minimum precaution.

Thanks again guy's you really are 'the biscuit'  :-)) :-))

Regards for now - Ramon
Title: Re: 1/8 scale hydroplane 'Atlas van Lines' build
Post by: MRZIPPYXXXX on August 07, 2009, 12:51:13 AM
Hi Ramon,
My application technique was trial and error with some advice from a pal who builds the big 2 metre span lightweight competition aerobatic aircraft.
I mix small amounts of straight SP113, not thinned, enough to work on one hull skin at a time.
With the hull propped to get the skin as horizontal as feasible with a curved surface, pour on a puddle and roller it out wetting the surface,
the roller (cut in half) covers a big area very quickly, much faster and even coating than by brushing.
Drape over the glass cloth allowing it to catch around a central point, and roller it out, pressing the cloth into the resin.
The trick is getting the thickness of resin correct, once mastered, the cloth seems to float suspended in the resin, and we get a good glossy flat finish straightaway,
if you can see the texture of the weave, roller on more resin while it's wet.
My past experiences with brushes have usually ended in disaster, when the brush catches the cloth, lifting it or laddering it, or pulling out the fibres etc,
finally ending up in the bin, the roller seems so easy to use!
The tech guy at SP recommended heating up the surface of the model and the pot of resin, to thin it, with a solarfilm heat gun! this helps it to flow better !!
Not sure about the fuel proofing of Halfords paint, my pal tried their Petrol resistant motorcycle fuel tank lacquer on his beautiful fully vinyl graphiced Cigarette
with disastrous results, not only did it lift said vinyl graphics, but also pickled off Halfords own paint ! 
I don't have this problem to worry about myself because, I hardly dare mention in present company, mines powered by one of those fast battery thingies,
will get back to you about my future plans - 2" to foot scale Huntsman or to be different perhaps a Huntress with twin brushless, sound generators, smoke the works,
finished also as round Britain racer, love anything produced by Fairey, have you seen the speeds they are getting these days out of the really big model lifeboats
weighting 1/2 cwt, with Brushless power.
Regards Paul
Title: Re: 1/8 scale hydroplane 'Atlas van Lines' build
Post by: martno1fan on August 07, 2009, 08:39:59 AM
I picked this massive hull up a while back for 50 quid  ok2 but it has no top yet,i wont be building her into a spearfish which i think shes designed as? or similar as i want to make her into a more modern style cruiser,shes 54"long.Layup is very very heavy so ill either sand it all away on the inside as theres pools of resin etc or ill mould off it and  make a lighter one.Sory for going of topic a little Ramon,im still watching your build i just have no input as regards nitro motors theyre just not my thing.
Mart
Title: Re: 1/8 scale hydroplane 'Atlas van Lines' build
Post by: Ramon on August 08, 2009, 10:13:48 PM
Hi Guys, Interesting post Paul,  :-)) I shall certainly use epoxy as a 'primer' on the hull now and get some rollers as you suggest. When you say 'mini rollers' are these the ones about 4" wide? and what weight of cloth are you using? Can you recommend a good source for supplying the cloth mail order.

I have warmed the work piece before but I'm surprised at the suggestion to warm the pot as well as this surely could kick off the process quicker than the resin can get used. Granted it was polyester but I remember mixing up too much when I first used G/F. As I was laying the resin on suddenly the jar became incredibly hot, the resin bubbling, cracking and spitting, setting extremely rapidly in the jar in front of me. Quite an alarming sight (well it was to me) if you don't know what is happening - which I didn't at the time. I've found it much better once mixed to pour the resin in a flat shallow dish which helps hold this exothermic reaction off.

I've found the SP site and take heart that it will accept most finishes. I still have quite a bit of cellulose left over from aircraft use so that's what I will use finishing off with the 'floor finish' previously mentioned.

I've had 'one or two' finishing disasters in my time as well but by the sound of it your friend had a real gut wrencher. One thing I have learnt is to try and keep the finishing products compatible.  Acrylic over a cellulose base is a definite no no - yep that was one of 'em! unless of course you actually want your model to look like an ancient Chinese vase!!!!  %%

Like the sound of the 'Sword' even if it is to have one of them new fangled leccy things in :o - I have to confess, as a long time user of these noisy, smelly, castor coated, infernal combustion machines I have had the odd sneaking idea that brushless may be a more 'user friendly' even, dare one think of it, more powerful way of going about it. But do they come with essence of methanol though - ah thereby lies the nub O0

Nice hull Mart, making a lighter one sounds like a good idea - at least you will have control over the finished item. Hang on in there on the nitro bit though it will soon be back on the build. Made the wing today and have modified the bracing on one fin tonight as the original position I put this in interfered with the wing. Hopefully will finish the other tomorrow then I can post a couple of pics.

Weather forecast is favourable next week so it's back on 'you know what' for a couple of days - I'd like to get that finished now so that I can concentrate on the hydro totally and get that finished before too much longer

Regards for now - Ramon

Title: Re: 1/8 scale hydroplane 'Atlas van Lines' build
Post by: martno1fan on August 08, 2009, 10:33:58 PM
Hey Ramon the acrylic laquer i used said it was ok to use on both acrylic and cellulose paints and it seemed to work fine it was from wilkos too  :}.This hull has lots of defects that you cant see in the pics like spider cracks here and there plus dents and an actual deep gouge where it was obviously dropped against somethinkg hard and sharp like a brick wall possibly.The seller didnt even answer my emails when i complained  <*<.Best is i said i wasnt too bothered but just wanted to tell him what id found plus lots of guys would be out for blood if they paid for something in that condition.Overall its a nice hull just way too heavy in fact i reckon it weghs 4 times one of my hulls even without a top.Will make a solid plug but im thinking of cutting off the bulbous transom and squaring it off?.
Mart
Title: Re: 1/8 scale hydroplane 'Atlas van Lines' build
Post by: andyn on August 08, 2009, 11:14:40 PM
No idea what it is Martin, but it sure as hell isn't a Spearfish. Good luck with it :-))
Title: Re: 1/8 scale hydroplane 'Atlas van Lines' build
Post by: martno1fan on August 09, 2009, 01:03:11 AM
Im not sure to be honest,does look very similar to me though.Not sure about the transom though but it has very similar strakes not sure about the ride pad?.
Mart
Title: Re: 1/8 scale hydroplane 'Atlas van Lines' build
Post by: andyn on August 09, 2009, 12:53:30 PM
This is a Spearfish:

(http://i288.photobucket.com/albums/ll184/andyn_01/DSCN3060.jpg)
Title: Re: 1/8 scale hydroplane 'Atlas van Lines' build
Post by: martno1fan on August 09, 2009, 04:45:08 PM
Still looks very similar it has the same funny shaped transom  just mine has the extra strakes at the chines,not having seen the real thing from the bottom im not sure what the real one looks like.I do like the bow shape on mine better though seems more streamlined so you could be right its not a spearfish just a lookalike,def looks like one of the fairey style hulls though.To be honest i dont think the guy knew himself what it was when i bought it.
Mart
Title: Re: 1/8 scale hydroplane 'Atlas van Lines' build
Post by: MRZIPPYXXXX on August 09, 2009, 08:03:04 PM
Hi Ramon,
Yes the rollers are the 4 inch wide white foam type, recently bought a bulk pack from local Poundstretcher Supermarket cheapest I have found to date,
razorsawing them in half makes them much easier to work with, unless you have a really large model.
Like yourself have used .6oz glass cloth with great success, my stock of this ran out, and I ended up finishing the Swordsman with 1oz "Deluxe Materials" cloth
from the local modelshop (Tonys Models & Hobbies in Leicester) this seemed harder work to manhandle, used more resin, but I am guessing a stronger result!
One of my reasons glassclothing - not enamoured with the quality of modern day 1/16 ply from the local model shop used for skinning of hulls etc,
lacks the evenly spaced dark/light laminations of stuff of years gone-by, and I am guessing possibly not marine quality.
I found the skins on Swordsman flexed alarmingly between bulkheads, and hoped the addition of resin and cloth might help stiffen things up, it did to some extent,
but next time I think I will be cloth inside and out.
Tried heating up the resin pot this morning as an experiment, forget it, did exactly the same as yours yuk, I think the techy guy at SP has been in a confined space
with his own product for too long !
Re electrics, if you have a crafty look in the Club Events and News section, here on Martins most excellent website, Wicksteed III the event, page 5 halfway down,
you will see the teeny tiny brushless outrunner powering my Swordsman, at what my IC club mates rate as quick as a modern day 40 glow, all for 20 quid !
My aerobatic pal has today installed a monster 5hp leccy up the sharp end of his latest aerobatic aircraft.  Regards Paul
Title: Re: 1/8 scale hydroplane 'Atlas van Lines' build
Post by: Ramon on August 10, 2009, 11:00:20 PM
Thanks Paul I shall get some at the weekend.  (Thinks - Something for the weekend Sir? Er yes please two rollers and a pot of epoxy! %))

I have ordered .6oz cloth from 'Hobbies' today This is a Deluxe Materials product 2 sq Mtrs - £10.50. Seems there is a problem in obtaining SP113 in greater quantities than 250 gms at present so shall look on the net for an alternative as this is a very expensive way of buying it.

Fins and wing are now complete and fitted.  The fins were built up using 1/32 ply skins over a bass wood frame then edged with reasonably hard balsa.

(http://lh3.ggpht.com/_XuA0NMLYOxg/SoCLcfQ17OI/AAAAAAAACWc/jP5OeNDgu0A/s640/DSCN1591.JPG)

Getting the holes through for the wing pivot posed a problem but some jury rigging ended up solving the problem

(http://lh3.ggpht.com/_XuA0NMLYOxg/SoCLdUJ1XoI/AAAAAAAACWg/GG5OjZ_wE2U/s640/DSCN1592.JPG)

I've just realised haven't took any pics of the finished assembly so perhaps a couple more later.

Had another think about those bad 'plucks' in the top skin. Tried a bit of P38 but this goes off so fast only very small amounts can be mixed - yes minimal hardener is being used. Anyway thought I might try 'Poly Filla'. Mixed some up with PVA glue and water and scraped it in. Seems to have worked, though the surface needs a light coat of sealer as soon as the excess has been sanded. I used very thin sanding sealer which should still allow the epoxy to penetrate. The nice thing was the ease of sanding.

(http://lh6.ggpht.com/_XuA0NMLYOxg/SoCLfnATqII/AAAAAAAACWw/DZA840C2zkI/s640/DSCN1596.JPG)

(http://lh5.ggpht.com/_XuA0NMLYOxg/SoCLgQVjdbI/AAAAAAAACW0/4_N9BZqLnXo/s640/DSCN1597.JPG)

Thanks again for the input Paul, now going to check out your Swordsman.

Regards for now - Ramon
Title: Re: 1/8 scale hydroplane 'Atlas van Lines' build
Post by: martno1fan on August 10, 2009, 11:14:49 PM
Ramon try this epoxy its really good stuff, it takes hrs to set but its very very strong.This is the faster one that i used  :o but its great stuff i got mine form a yacht builders its really top grade stuff .I still have some left after building the rockett and also using it on other builds too so its plenty and then some.I usually clamp things up and leave them overnight then its done.
Mart
http://cgi.ebay.co.uk/SP-106-Multi-Purpose-Epoxy-Resin-System-Fast_W0QQitemZ220387124281QQcmdZViewItemQQptZUK_CarsParts_Vehicles_BoatEquipment_Accessories_SM?hash=item335018a439&_trksid=p3286.c0.m14 (http://cgi.ebay.co.uk/SP-106-Multi-Purpose-Epoxy-Resin-System-Fast_W0QQitemZ220387124281QQcmdZViewItemQQptZUK_CarsParts_Vehicles_BoatEquipment_Accessories_SM?hash=item335018a439&_trksid=p3286.c0.m14)
Title: Re: 1/8 scale hydroplane 'Atlas van Lines' build
Post by: Tug-Kenny on August 11, 2009, 11:05:49 AM
Ramon try this epoxy its really good stuff, it takes hrs to set but its very very strong.This is the faster one that i used  :o but its great stuff i got mine form a yacht builders its really top grade stuff .I still have some left after building the rockett and also using it on other builds too so its plenty and then some.I usually clamp things up and leave them overnight then its done.
Mart
http://cgi.ebay.co.uk/SP-106-Multi-Purpose-Epoxy-Resin-System-Fast_W0QQitemZ220387124281QQcmdZViewItemQQptZUK_CarsParts_Vehicles_BoatEquipment_Accessories_SM?hash=item335018a439&_trksid=p3286.c0.m14 (http://cgi.ebay.co.uk/SP-106-Multi-Purpose-Epoxy-Resin-System-Fast_W0QQitemZ220387124281QQcmdZViewItemQQptZUK_CarsParts_Vehicles_BoatEquipment_Accessories_SM?hash=item335018a439&_trksid=p3286.c0.m14)

I use this product as well. It's just the job for us. I also note the other products he sells; ie moulding material and filler to thicken up the epoxy. Very good

ken
Title: Re: 1/8 scale hydroplane 'Atlas van Lines' build
Post by: Baz2 on August 11, 2009, 02:17:55 PM


  Hi Ramon

     A great build Ramon, I've been following it with great interest.
   
          Who knows I might have a go at this one myself ?

               keep up the good work.

                                    Baz
Title: Re: 1/8 scale hydroplane 'Atlas van Lines' build
Post by: Ramon on August 12, 2009, 10:25:36 PM

Thanks for the info Mart and your confirmation of it too Tug - (Ah! would I be right in thinking you're a 'Wilson' too!)
I have enough of the SP113 to finish the hydro but will look into getting this 206 for the next (??? ;)???) build.

Now Mart have patience here as it's 'back on the engine bit' -

Following on from float chambers I'm afraid I don't have room for a float chamber - definitely don't - (unless I kick the radio out that is which means too much pulling about at this stage. Of course if there isn't enough capacity for a reasonable run that may have to happen at a later date!) I have bought a couple off ebay so now have a good idea what they look like and how they function but there's ''no room at the inn' on this build at present.
that, unlike the float chamber, it will mean the fuel is under pressure 'at the venturi' but it should act as a kind of 'compensator' and keep the head of fuel fairly consistent. I'm thinking that by venting it when filling then closing the vent it will continue to fill as the fuel is drawn off. The slight vacuum in the head of the tank may help keep the head of fuel above the level of the fill pipe and if it works as I think it might then when the engine is throttled back and the pressure reduced then it may act with a semi uniflow action. Another suck it and see event - any opinions?

Forgive the sketch - done in best pre CAD fashion I'm afraid!

(http://lh5.ggpht.com/_XuA0NMLYOxg/SoCK6rx-WVI/AAAAAAAACWQ/lNhDYusa7VU/s640/img006069.jpg)

(http://lh4.ggpht.com/_XuA0NMLYOxg/SoMI3C2AnwI/AAAAAAAACYA/EabAz3yhmX8/s640/DSCN1599.JPG)

Feed in from the tank on the left, fuel pick up in centre, vent on the right. The cup is the sump (to be glued in with JB Weld).

Ready to fit
(http://lh6.ggpht.com/_XuA0NMLYOxg/SoMI5Qg1kXI/AAAAAAAACYM/y36a2UHz7_s/s640/DSCN1602.JPG)

I have also made a similar but much small chamber to act as a back pressure overflow from the exhaust to fit 'tween exhaust pressure outlet and vent on first tank.

Couple of pics of the wing and fins.
The whole unit is held on with 4mm nylon bolts in aid of 'breakoffability' (bet Windows hasn't got that one!). The wing pivots on them too - just need to work out a method of adjusting the wing incidence that will hold it rigidly but can break apart as well. The struts are made from 2.5 ally welding rod, the ends squashed in a vice and drilled. I don't expect these to survive a tumble but they are man enough to keep the whole thing rigid.

(http://lh5.ggpht.com/_XuA0NMLYOxg/SoMI6dvk_aI/AAAAAAAACYQ/T8O1z8XWTkQ/s640/DSCN1603.JPG)

(http://lh6.ggpht.com/_XuA0NMLYOxg/SoMI60Hn-7I/AAAAAAAACYU/nsORU_38r3s/s640/DSCN1604.JPG)

(http://lh6.ggpht.com/_XuA0NMLYOxg/SoMI8OBaQ9I/AAAAAAAACYc/3D64ineMReY/s640/DSCN1606.JPG)

That's all for now, glad you are inspired Baz, break out that ply - it would be really great to hear of another one being built.

Things are looking like it's a few days back on the Huntsman again, but in the meantime let me know what you think on the fuel set up.

Regards - Ramon
Title: Re: 1/8 scale hydroplane 'Atlas van Lines' build
Post by: Ramon on August 12, 2009, 11:11:47 PM

Just realised that this bit of text is missing - (this post really has had it's share of gremlins)
Quote
.........there's ''no room at the inn' on this build at present.
Sooo - I thought about the last replies on the matter and have decided to put in a small (non float) chamber that will (hopefully that is %)) be fed from the feeder tank under pressure. I realise this will mean that,
Quote
....... unlike the float chamber, it will mean the fuel is under pressure 'at the venturi' but it should act as a kind of 'compensator' ........

 
Hope that makes a bit more sense
Ramon
Title: Re: 1/8 scale hydroplane 'Atlas van Lines' build
Post by: martno1fan on August 14, 2009, 11:58:42 AM
Hey Ramon what about a v 12 for it  :o lol
Mart
http://www.classichydros.com/merlin.htm (http://www.classichydros.com/merlin.htm)
Title: Re: 1/8 scale hydroplane 'Atlas van Lines' build
Post by: Ramon on August 14, 2009, 03:16:02 PM
Hi Mart,
Thats a shame the boat's 1/8 scale {:-{ Howeverrrr.. could be ok for the next one  ;)

Wonder if it will fit over an engine/pipe without too much problem?

Read your post for the video but still haven't got this fixed yet - 'Thought' (Hell, that hurt!) will put it in for fixin' when I'm on holiday next month.

Regards - Ramon
Title: Re: 1/8 scale hydroplane 'Atlas van Lines' build
Post by: martno1fan on August 14, 2009, 05:46:40 PM
I know the engine is 1/6 but they fit just fine in the 1/8 scale hulls or seem to do from the ones ive seen.Im thinking of maybe fabbing one up myself from balsa and scrap bits of plywood.
Mart
Title: Re: 1/8 scale hydroplane 'Atlas van Lines' build
Post by: martno1fan on September 28, 2009, 11:54:24 AM
Any updates Ramon  ok2
Title: Re: 1/8 scale hydroplane 'Atlas van Lines' build
Post by: cadman17_36 on November 10, 2009, 04:37:07 AM
Hi all hope all is well I have been readinf this post with great intrest. Hope to see the finishe product soon and maybe even a vid of it on the water?? :embarrassed: I also have these plans and will be doing one my self when I can get someplace to build in. I was lucky enough to see this boat run here in the states when Bill Muncey and Chip Henauer Were the drivers there is nothing like hearing those big V-12's fire up and run for the money. here is a site that mite help a bit (http://www.thunderboats.org) they have a link to the rstoration of the 1982 version of the Atlas when the added conards to the front and extended the cockpit forward over the leading edge I beleave they extended the airtraps also. Good luck and keep posting and building
Title: Re: 1/8 scale hydroplane 'Atlas van Lines' build
Post by: Nordsee on November 27, 2009, 02:06:46 PM
Hello, oh how that takes me back! In the middle 80s I built a model of the Atlas Van Lines Hydroplane. Not as big as yours , it was from a Radio Modeller Plan and sported a 540 motor and 8 cells. It went quite well, got onto the step and planed. Turning was not very good at all, needed to slow down and just turn on the rudder, I wonder how it would have performed today equipped with a Brushless and Lipos! Sold it to a Model Shop for a window display and they sold it on 2 days later! Wonder if it is still around? James
Title: Re: 1/8 scale hydroplane 'Atlas van Lines' build
Post by: vasek on November 25, 2011, 10:47:53 PM
Hello gentlemen, I'll be watching this build with interest... my first post here. I am starting a 1/8 Miss Renault '83 from Newton plans and will have a framing kit. I am a newbee to boats.

Although I am going electric for power, the hull construction is similar, thus my interest in this build.

I will start with 2 questions:

1- Where can I get some 1/16" marine ply for sheeting ? UK source that ships to EU would be perfect for me.

2- How can I upload an avatar? I did check my profile, but couldn't locate the link.

Thank you for helping,
Vasek
Title: Re: 1/8 scale hydroplane 'Atlas van Lines' build
Post by: Arrow5 on November 25, 2011, 10:53:28 PM
Vasek, 1.5mm birch ply should be available in model aircraft shops in your country.  Czech Republic ...or ?
Title: Re: 1/8 scale hydroplane 'Atlas van Lines' build
Post by: martno1fan on November 25, 2011, 11:02:30 PM
Heres one im building for a customer from my moulds ,yes shes glass but still a bit of wood in there  ;),deck went on today and the cowl will be fitted tomorrow.She will be powered by a modded zenoah motor (zen 7 ).
Mart