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[red181]

Hi all, and Merry Christmas

I have finally reached the point that I can "almost" call my Veron Huntsman 28 completed. I gained a lot of valuable help and assistance from a number of forums, primarily here, and would like to thank everyone who took the time and effort to reply to my MANY questions over the last couple of years, BIG thanks to one forum member, who kept me going through some very bad times when the boat came close to the bin, he will know the WORST recent experience!! without his input and experience I doubt I would have reached this point.

I call myself a relative novice in RC boat building, I have experience of 2 other RC boats, and helicopters, I have a good eye for detail, but struggle hammering a nail straight without spliting the wood or bending the nail, and I take on a project such as this, an all ply 48" boat , so this thread will not drift away, I will take you right to the end, and cover all my new skills, vac forming, planking, fibreglassing, painting, electric setup, and that mystery of fast brushless, gearboxes,and props on a large scale boat. Hopefully other novices can take something from this thread.

NOW.....I saw the boat on ebay Xmas 2006, liked the look of it, and wanted something to play with as a project, so I didnt build from scratch, its a refurb, I think the recent build from Ramon is excellent, and Derek Bradley is also covering building from scratch, I do not possess the skills for that! Didnt even know at the time what the boat was.

After winning the bid, the boat arrived, it had a large Johnson motor, and a Ripmax seasprint esc, and was a runner, it looked really nice. Later I found out it was a Fairey Huntsman, and the Fairey owners club verified it was a 28, I had hoped it was the boat made famous by Sean Connery in "From Russia With Love", whilst the 28 featured as chase boats, Bond was in a Huntress, so my plan of replicating that boat failed.

It was June 07 before it came out of the attic for its first trail, very slow, but looked like it had potential!

[red181]

After its first run, everything was stripped out late Autumn 2007. Another build had taken a long time to complete, so the Huntsman lived in the attic most of the year

It took ages to strip the layers and layers of thick paint. I wanted it back to wood. It was very well made, and very sturdy. Paint removal was with paint stripper, electric sander, scraper, dremell, and took an age to do. After all the horrible paint was off, It had to be washed down several times to get rid of any paint stripper traces.

Mistake 1/ starting to paint when weather is getting cold!

Its now late October 2007, I build/paint in what is best described as a shed/garage. Not very warm. I used Halfords Primer, the yellow one with filler. Goes on ok, you can see what you are doing, but it kept cracking after It was left some time, and the filler build up wasnt that good. I carried on, and painted  several primer coats, flatting with 600 wet and dry, then 1000 wet and dry, very time consuming and labour intensive, but a good prep here means a good finish later.

Decided to use Plasticoat paint, its readily available and reasonable price for a large tin. The blue is a very good match for the Fairey colour, and white is nice bright sharp white. Several coats, process as above, flatting between each coat. Then I used a bodyshop rubbing/flatting polish, (G3), very hard work, but worth the effort!, then T-Cut, then polish up with a nice creamy polish (advantages of working in a car dealer, loads of polish products available!

Should not have ignored the warning signs of cracking primer!!!

[red181]

AS you can see the roof has come off, it was damaged in the paint removal process, and I was unsure if I wanted to keep the large access panel, it was ugly.

Its now mid 2008, and I had started a couple of jobs on the boat to keep me interested, to break up the boring jobs. I decided to plank the interior, using some real boat photos for reference. Although not 100% realistic, I wanted a nice shiny finish on the interior decking, and used clear varnish to get the finish, after a number of sanding sealer coats. I rubbed each coat (approx 5) with 1000 wet and dry to eliminate that horrible treacle finish when its dawbed on too thick, and used evergreen plastic strips to give the finish between the planks like the real Huntsman.

Back to the cracking that I ignored, the blue paint on the cabin sides has now got very fine cracks, only visible close up,  and after much dilema, I decided to get it back to wood and start again, incase it got worse over time. Subsequently found out, plasticoat and Halfords primer dont get on, so all the primer has to come off, and start all over again! , also, painting in the cold probably didnt help, although 6 months has elapsed, is the wood shrinking?? maybe another problem that wasnt evident when the boat was covered in thick red dulux! 

[red181]

so not much more happened in 2008, got myself a RC Orca Jaws boat, that was a really fun build, that coupled with full time job, RC helicopter project and 3 kids didnt really leave much spare time

The window frames are made from plasticard, cut out by hand in one piece, and seperate tiny rivets, each one drilled and glued, then they had to come off for the repaint on the refit, I used a different method, much easier and more "scale like", more on that later. so now the first "new skill". I was persuaded to fibreglass the new roof, and cabin sides, to stop the cracking. I resisted for ages, even decided to plank the deck, but eventually gave in and did the fibreglassing.

So the planking (yes I know, all over the place here, this is the back to front way I did things!). Never done planking before, I tried pencil lines, looked rubbish, tried a wood scriber, rubbish, so the only way to get it right is real planks. Photos of real Huntsmans showed the planks to have gone very pale with sun bleaching, and the caulking to be a grey colour, so off we go.

The sides of the deck where pretty easy, but at the bow, how was I going to bend the wood? Could have just gone straight, but it would not have been correct. Tried to get the joggle effect, but that was just too hard.. So bending planks, tried to steam them, soak them in the bath for days, heat over gas ring, etc etc etc, nothing worked. Eventually, got a piece of MDF, cut it in half, in a circular cut similar to the radius of the bow planks, split the 2 pieces the width of a plank, nailed them to another piece of MDF, soaked the planks in boiling water, and forced them into the homemade jig, left to dry for a few days, and then using small clamps and wood glue fitted them!. This took 2 weeks as it was such a slow process, fitting one plank, them having to wait for it to go off and stick hard, as the next plank has to be bent against it. The grey caulking is grey card from a stationary supplier, that too had to be glued into place and left to harden before the next plank, I was now getting real fed up!

not the best of pics, but the planking is on, but now to get the weathered effect. I used a wash, made up of a combination of grey and white thinned out paint, it gave exactly the finish I wanted, but all that hard work with the caulking is now lost, stupid me :embarrassed:the caulking has soaked up the wash and disappeared, back to the drawing board!!

[red181]

Its at this point, in a real low mood, that I decide to HATE the roof access panel, so off it came!!! ( the new roof that is, it had even been painted

The roof on the Huntsman is quite a complex shape, and the curvatures just dont allow a one piece roof, Ramons build explains this, so its off to my mate's who is an expert carpenter, and modeller, he fits a 2 piece roof, with a nice accurate roof overhang, I watched in awe as he did this, its great to see a craftsman at work!

 I didnt want to lose the wonderful large area in the cabin, so he talks me into removing the rear of the cabin and creating a different access point. A great idea, that works wonderfully. I can now make a detailed dashboard, cabin door etc off the boat, painted and fitted, and I use 3 small neodyme magnets to hold it in place. These are very cheap, and very strong, that panel is not coming off when the boat is in use, and all the electrics can now be mounted in the lovely dry cabin. I planned to use a sound unit, and thought this was an ideal place for a speaker, a ready made sound box, this is not required now, you will see why later!  

[red181]

so now its getting a bit messy, there are a few things going on, the roof needs finishing, its 2 piece, so I have to lose the joint, the access at the back needs the dashboard making, I have painted the hull, blue underneath, and white sides, and the rubbing strips are finished.

Mistake 2/ waterline is wrong , don't know how I got this so wrong (its actually right when on the plane!) but I cannot paint it again, that will have to come later.

Dashboard and door panel is plasticard 2mm thick, lovely to paint after all the prep wood needs, its light, and can be glued. Instrument panel is a copy of a real boat, red and green throttles are pins, instruments are the becc ones, and the dial bezels are portholes painted up silver. The neo magnets are sunk into the surrounding area where the panel was cut out, and resined in so they don't move or fall out, I expect this boat to get a rough time in high seas!, so nothing can fall off!

Back to the fibre glassing, very light fibreglass cloth from delux materials, and a nice light resin to go with it, no point using the heavy halfords type, boat will get too heavy, and too much work rubbing it down. I have prepared the wood with 600 grit, 600 wet and dry using a block all the time, them down to 1000 and 1200 wet and dry, its lovely and smooth. Resin was used in the joint to flat it up. The cloth is the sort aero boys use for wing coverings, and the intention is to hold all the wood together, and on the cabin sides, to stop the cracking. The planking has been done, another job in the wrong order, so glassing the sides is a very hard job now, got to protect the planking....

[Bradley]

A very interesting build thred, Red181 and I shall follow it with great interest.   I can see why you got so frustrated at times but it must have been worth it as the boat is looking good.

Derek.

[red181]

ok, if anyone has not done glass fibre, its easy I have done it twice now, you have to get the resin on before it starts going off, in nice light coats, not dolloped on, I use an old plastic card to apply.

 When hard, a sanding block on the edges removes the excess cloth. I now prepared the sides and roof. Filler primer, not halfords due to previous experience, using Hycote. Couple of coats, then its time to start rubbing down, with 400 wet and dry and a sanding block, not without block,  as then you get all manner of undulations, 600, then 1000. I put some fairey liquid in the water, nice and easy to use, you can actually hear when you are nearly there with the finish, as the scraping sound stops! when I think its ready, light primer coat, inspection, and repeat the process until happy. Good preparation means no need to start piling on a load of filler, that just means hard work rubbing down, and I am always concerned that the filler could crack if the boat is knockled about after paint.

About 7 coats later, its time for the top coat, plasticoat white for roof, and blue for cabin sides, as per Fairey boat colour schemes.. The process is repeated, coat of paint, 600 and 1000 wet dry, then another coat, approx 5 coats, letting every coat dry properly. After final coat, G3 rubbing compound, and then t cut and final polish, thats why several coats are required, G3 and t cut remove paint, and I don't want to go through the paint at this stage. The finish is now silky smooth, with a very nice finish and reflection.I used low tack masking tape so that previously painted areas are not damaged

New window frames now, cut again from 1 piece of plasticard, very fiddly! cut the inside first, then the outside so they keep the shape. I then got assistance, and drilled from the inside using a 2mm drill bit a hole but stopped just before the hole penetrated. Painted using aluminium humbrol paint again from inside, the paint now fills the holes, and gives the appearance from the outside of rivet heads! , its only when you run your finger along the plastic that you find there are no rivet heads there, just an optical illusion (thanks Peter!) Since its painted from the inside, the clear plasticard frames are now nicely finished from the outside. I had to lightly rub down the edge of the cabin sides they are glued on to make the glue adhere, and used a glue from delux materials, Plastic friendly, as super glue and cyno would bring the aluminium paint off.
The front frame on the Huntsman has no rivets, Its either an opening or escape window. Same process to make, but a second thinner strip to replicate the real thing.
A visit to a local window tint company, and an offcut of 50% tint, applied to the clear plasticard used for glazing, and hey presto, nice tinted windows!

[red181]

As you can see, I have done this build in all the wrong order, favouring the jobs that interst me, now........the job from Hell! , the windscreen!

I didn't want to use thin plastic card, thinking it would be too flimsy when the boat is going fast, so decided to make my own. First attempts where to use 2mm plastic sheet, the sort available from DIY shops for sink splashbacks etc. I made a paper template, then transferred to thicker card. A support was fitted to the roof, its visible on the last picture, the idea being that the screen would "lean" on this, and nobody would be able to tell that behind the screen was higher than the front side, very clever, (not my idea I must add!)

Cut the plastic sheet, a real nasty job as the plastic heats up when being cut and is horrible to work with. I then tried bending it freehand, heating over a gas ring, failure , in hot water, failure  , and in the oven another failure . Time to do it properly. Using now a cut up biscuit tin, I transferred the card template to this, and made the windscreen shape (its a very complex shape ). I then made from the previously used MDF a wood form to fit inside the biscuit tin shape to hold it rigid, now I have a template to make the windscreen on!

Went to Argos and invested £10 in  a heat gun, and now had controlled heat on the next piece of plastic sheet. Unfortunately, this didn't work, the tolerance between hot enough to bend, and too hot that is bubbled was too close, but I knew I was on to something here! Next attempt was with Lexan 2mm sheet, which was donated from my friend and motivator!, don't know where he got it, but Lexan worked. Using heatgun on low setting, it heated up just right, and bent over the template. 2nd attempt was fine, however, next year I plan to make another,  as I know I can now do a better job. B & Q has plastic "u" profile strips that fitted over the top edge real snug, and I then cut thin strips of plasticard (off cuts that where for sale at the Warrington show from SHG Marine), a couple of other strips on the screen, and I have the screen frame, inside and outside of the lexan. These where then painted and polished up in Steel colour metalcote paint, and using the same window tint film, this was applied. Now you might ask why tint the windows, it hides any glazing imperfections, makes it harder to see inside the cabin (So I don't have to fit an interior) and some of the real boats had this, I think its a nice touch, its not as dark in the flesh as in the photos, but I would like to do the windscreen again.

[red181]

Now the windscreen is almost done, its matter of securing it in place, and a way that facilitates easy removal in event of it being broken, previous photo shows 2 small bolts, on the outside I made a plate they screw into, from thin brass sheet, and soft soldered 2 brass nuts on. This plate will  be hidden by the trade mark Air scoops that Huntsman boats have.

Mistake 3/ when drilling holes for fittings on the roof, I used a blunt drill, on a low speed, and damaged the roof paint finish as it "dragged" the fibreglass cloth. In normal light, its pretty much none visible, but I know its there and it annoys me, another job for next summer, repaint the  roof! AGAIN!!!!!!!!!!!!!!!!!

Hatch is made from plasticard, roof rails are long kebab sticks, dipped in exterior woodstain several times (also used this paint for the edges of the exterior deck, to give a nice contrast, and a finish that will be easy to touch up when its had a few knocks), and you can see the plates that secure the screen, painted in blue

[Shipmate60]

Red181
She is a credit to you, she looks superb.

Bob

[red181]

Next project, VAC - FORMING!!

I wanted to have good quality realistic chrome (preferably) air intakes, these are hand beaten on the real boat, and for me are a major part of the model, as they are very rarely replicated realistically. I tried cutting up various plastic chrome painted toys, cups, jars, tried cutting up backs of various spoons, and other kitchen implements, nothing worked. Even tried searching work and home (and other peoples homes!!) for something that would be an air scoop. I even gave up on the chrome finish, and thought I would settle for white, as some boats have this, but nothing worked

Now, remember the craftsman friend???? well, on a visit to see him, he produced 2 (left and right) hand carved air vents, specially made for me to stop me moaning on  and on about them!! , and he suggested, why not vac form? After weeks of resisting, I build my vac former, and went to work, believe me, its EASY!!, you can vac form virtually anything!, look out for my seats later!.

Made a box, drilled loads of hole out of the top, fitted the hose from the vacuum into a hole on the side, duck tape around everything to make it air tight. Then made a frame to fit on top, stapled a sheet of plasticard onto it, stuffed it in the oven till the plasticard went "wobbly", turned on the vacuum, and put the hot pasticard over the 2 wood vents, hey presto, vac formed air scoops!!!!

I have now made loads, each set getting better!. Now, painted a set in hycoate chrome finish, and they looked superb, BUT.... when wet, the chrome paint got tarnished, so have to rethink the finish. For now, I have made a set in white, and am currently doing another set in clear plasticard, and will pant from the inside in Alclad chrome paint. This paint is specially developed for painting the lexan and polycarbonate bodyshell of RC cars from the inside, so I think (after seeing some test samples) it should work a treat. The rivet effect will be as per the same process that the window frames got

[red181]

So now its looking all pretty, (again in the complete wrong order!) its time to get this (now getting heavy!) boat running

SET UP 1

Graupner 700 BB turbo 12v, direct drive, 19.2v nimh, various props, best was 50mm "x", Ripmax seasprint esc.

Performance acceptable, but didn't give me grin factor, looked pretty on the water, but just didn't hit the sweet spot. After 20 boring minutes on Newsham Liverpool, and GPS showing 14mph, slower than my Aerokits Fireboat, its back to the drawing board, that was April 2009.

SET UP 2

Finally listened to advice that was being given all year, gearbox. Now, the gearbox has been custom made, and is a work of art! (not made by me, remember I cant knock a nail in straight!). It is aluminium, and uses MFA gears, with belt drive. The MFA website has a gear ratio and belt size calculator. I wanted to test 2:1, and as the gears are cheap, also tried 1.5:1 4mm shaft was used originally, and now used a 9.6v graupner motor, everything else was same spec.
Boat ran faster (unfortunately didn't have GPS) but more importantly was stone cold (it is water cooled) and ran for 15 mins longer, now approx 35 mins flat out, a definite improvement, but still not fast enough.

I really contradict myself, want the boat to look as realistic and authentic as possible, but want ballistic way over scale speed!
The 9.6v and 8.4v Graupner motors are very hardwaring, and you can over volt them easily, these 2 have a much higher rev than the 12v, which was pedestrian with the gearbox

The big job here was setting the prop angle. The original Veron plans are set up for IC, meaning the angle of the prop is far too great. It was a real bad job to get the old motor mount out (see chisel!) but once out a pretty easy job to reset another, all set in resin, and the motor mount screwed into blind nuts, this fast set up needs to be accurate and secure, no need now for a coupling, everything is dead straight, eliminating weak plastic universal joints that just eat your amps up

[MRZIPPYXXXX]

Well done Paul,
This has livened up the Xmas break for the Huntsman appreciation society here in Leicester !
finding this really interesting, nice to see a bit of thinking 'outside the box' - chopping a great whole through the cockpit bulkhead - genius !
and the vac formed air scoops are a really clever idea.
I nearly went the clear plasticard/Alclad route on my Swordsman window fames, ended up the usual spraying the Alclad on the outside method
and its already starting to tarnish etc with water damage.
Any more info/pics of the gearbox? - looks the business.
The offers still open, anytime you want a large lake where you can really open her up!
Regards Paul

[red181]

Hi Zippy! , thanks for comments, although I am surprised its been a quiet thread given the boat and topics being covered, will def come and see you, but when its past the "test" stage, at present being a coward in small lakes so I don't have to wait ages for it to float in!

Now on with the pantomime!

so the prop angle has been set, ( much shallower angle than was already installed, meaning cog of motor will be lower.) new motor mount in, water pickup already fitted, and for now leaving the original rudder, The rudder servo is the original sanyo one, not expecting anything special from that. Using (from prop end) silicon bearing at bottom, this lubricates with water, ballrace at top, ballrace at entry point into motor mount, and at exit point, so the prop is supported by 3 bearings, 4mm shaft only because I have a few 4mm props to test with, and thats what was in the boat . Now, an oil tube filler has been soldered on the shaft, This is a pretty simple job, I do not like to fill the shaft with grease, on a fast application, the grease will just "tunnel"around the shaft and serve no purpose at all, and after time will harden. The only part of the shaft that requires lubrication is where the bearings are, and one of them is self lubricating when wet.


Mistake 4/ never get distracted when testing! I took the boat early one July sunday morning to New Brighton. This lake, on the tip of the Wirral Peninsula is superb for testing. Not that big, but raised sides, so you are not having to worry about shallow water, or a long reach down to get the boat in the water, also, being right on the coast, there is usually a breeze, so in the event of failure it will float in quick , and if the worse happens, its shallow enough to wade out!, you can see I am confident of success!

After a few minutes razzing around the lake, a couple of club member's arrived and started talking. I was changing the 9.6v graupner to an 8.4v one, chatting, put the boat back in the water, couple of circuits, then brought it in (by the way, not much if any difference between 9.6 and 8.4). Started to pack up as I didint want to run a large fast boat on a small lake with others, and at the time I was on 40mhz, didn't want to run risk of any frequency clash. I noticed that the cabin windows where steamed up, now for anyone that is familiar with old cars, that ususally means damp inside, in this case, water leak!!
Took the dash panel off, and the cabin was 3 inches deep in water!, stupid boy had left the water cooling hose off in the motor swap, and the boat had merrily been filling itself up with water! , that was the end of the receiver, it never worked again,

Next project was the mast. I wanted a removeable one, so, if it need to be removed for transportation or storage, or it got broken, It could be replaced. Using a hollow piece of plastic tube from a discarded kite (will it was after the tube went missing!) I fitted it into the base of the cabin using another hollow piece of ally tube. A small bolt through both keeps it in place. Hollow, as the mast has a nav light, and I wanted the wire inside, this has a small plug so it can be disconnected if the mast is removed. To paint it, it was primed, then dipped several times into the exterior wood stain, thus no brush marks!

[red181]

some real nice cosmetic moments now, the rear seat was made from a box section from plasticard, and the cushions are carved and sanded from balsa (not by me, you know who!), painted matt white, sanded with 2000 grit, and given a slight bit of weathering with acrylic pencils (white and grey) my arty daughter does have a use after all! .

Front fender was bought from Scale Hobbies, it wasnt in stock I took the boat to him, he smiled and said I will phone you when its made! Dont know to this day where he got it, but he is a top bloke, it fits perfect!. Chrome fittings are very ellusive, I got some aeronaut ones, I think it was from someone in Cormnwall? just cant remember, but the cleats and davits where very hard to find. Rear corners are just plastic card from an easter egg package, covered with chrome sticky back plastic, and dressmakers pins for the rivets (overscale, but look nice!) Chrome anchor winch and chrome (well nickel plated) anchor from Scale Hobbies again.

Rear ladder is made from brass tube, with brass rod. Steps are hardwood then stained and varnished. I was quite proud of the ladder as it involved a fair bit of soldering, and was very fiddly, putting the tube on the rod, solder, fit the step, then the rod again, solder, and so on, then all masked up for painting, 4 small washers wher the rod goes into the transom (nautical terms now eh! getting the hang of this boat thing! )

NAMING OF BOAT!!

THe lettering are from a company on Fleabay, I have used them a few times, he basically does anything you want, and is next day turn around, excellent. I repliated the font used on most of the Huntsman I was copying, and its the nickname of my daughter, so it means something to me! I think little touches like this personalise the boat. I fgot 5 sets for less than a fiver, different sizes and colours, this was the best

[red181]

Back to the set up then.

Still wasn't getting the hairs on the back of my neck to stand up!, after 5 or 6 runs, august time, I decided I wanted better, so sold some helicopter stuff on fleabay to fund a brushless project. I did a LOT of research, and info is very hard to find, so I hope this is of benefit to others. I cannot say this is the best set up, it probably isn't, and even now I have not got the right set up, but weather, family, job etc are very time consuming and its difficult to devote time to testing, also, paypal is empty!!

Most info for brushless is for very light racing boats, this boat is now over 6kg, fat old girl! , so covering different forums, nobody actually came out and said I have the answer, so perhaps a bit of trail blazing here.  I had settled on a feigio motor, 540xl, 10 turns, after trawling forums for a month, this motor seemed to give the acceptable spec, but it was to be very much trial and error. It seems that more KV on a brushless motor, less torque, and I need both! On the day that I was about to buy, I did a final look at Ebay, and found an Align 600l 1640 kv motor, usually retailing the £80 mark, never used, mine for £25.00!!, what a steal!. This motor had been suggested by two people but was out of my league price wise. Its an outrunner, but also has an outer can. I have used Align before with helis, it is a favoured choice, so quality and reliability are good, however its intended for a 500 (large) size RC Helicopter, which has substantially different uses. This was couple with a Castle Creations Barracuda 80amp forward/reverse esc. Expensive, but on sale with Overlander, and I had sold 3 heli's, so the cash was there(just!)

SET UP 3

THe Align motor, 19.2v nimh, 2:1 ratio, 50mm prop
http://www.youtube.com/watch?v=yitqLxoSIJs

Unfortunately the batteries had started to go off, and the lake is a bit small, I was scared of hitting the sides, but everything ran stone cold, so changed the prop to 52.5mm, it went faster, but did not get on film unfortunately

[Bradley]

Red181,
Can't understand why there has been no comment on your build thread as I think it is great and have been following it avidly .  I see that it has been viewed 299 times to date so, the interest appears to be there even if there are no comments .  Personally, I find your change to brushless, etc., interesting as this is still a route I am considering with my Precedent Huntsman. 
Your boat looks superb and the action shots show how worthwhile it has all been.
Keep up the good work.

Derek.

[red181]

thanks Derek! unfortunately I don't have the woodworking skills you posses, so cant start a build from scratch. My other 2 boats where also refurbs like this one. As you can probably tell, I enjoy the fiddly cosmetic things very much, such as getting the Fairey logos on the 2 mugs on top of the dashboard!

Short post for now, (family duties!) after reading back, I have not really posted much detail about how I arrived at the motor/esc/prop set up, kind of brushed over it, and it probably deserves a bit more attention. I am very lucky, the friend who mentored me through this build, had quite a few props, different sizes, shapes etc, and without this I could not have made such progress. Now as a relative novice, I had not realised how important the prop is, in terms of amp draw, resulting in heat, or overheating , power to move the boat and efficiency, in terms of run time.

If I use my other boat as an example, Areokits Fireboat 36". The best "cheap" prop was an "x" plastic racing prop, probably the most common in use, 45mm. This gave an acceptable performance/run time/heat. After reading some information provided by Mr Zippy on this forum, I borrowed a cleaver style 4 blade prop. The difference was astonishing, run time improved, less heat (same set up could now run without water cooling, and for me more importantly it went faster. From a cosmetic point, a nice 4 blade brass prop will always look nicer than a plastic one. I bought it from propshop. There have been a number of posts asking if they are still trading, well they definitely are, I think they trade under the name of Swan. It cost about £18.00, expensive compared to £3.00 plastic ones, but once you are past the testing stage, worth the money, no horrible solder joints, nicely balanced, and very smooth, trust me, why spend a fortune on everything else and ignore the thing that actually moves the boat

So, when I  have arrived at what I think is the best prop for the Huntsman, I need to find something else to sell on fleabay, and last years kids Xmas pressies are calling to me.....

Ok, so you might be thinking, well borrow again, its 4mm shaft, but... there was a problem. After a number of test runs, the shaft gear started to slip on the shaft, to the point that it stuck, almost fused on. Closer inspection also showed that the motor was running hotter than I had realised, the aluminium mount and gearbox was acting as a heatsink and fooling me, so the 52.5mm prop that I had settled on was too big  matter how tight the grub screws where, it just kept slipping after 2 runs, then I noticed an imbalance occurring on the shaft, it was bending, after the gear, like a whip effect, more on this later

[boatmadman]

Red,

This is a great thread, keep it up!

Ian

[cbr900]

Red,

Absolutely fascinating good job mate can't wait to hear more.........


Roy

[SteamboatPhil]

I have been watching this from the beginning, and it has been a great build / refurb (seems more build to me) thread. It really looks the biz (I'm watching Derek's build as well) But what got me big time (wait for it) as I was reading last night, was the home built vac form machine !!!!!!!! how simple/easy/bl**dy clever/ why had no one come up with something like that before. Guess where I was this morning (until the cold got to much) building my own one (build log as soon as fingers thaw out).
Congratulations (on build and vac form machine)
 

[red181]

Thanks Phil, just a quick note on the vac forming, I was TOLD to get on with doing that for weeks!! Never thinking how easy it would be. I have noticed that different plasticard gets different results, and you have to catch the card at the right moment, it goes floppy, then wobbly! in the oven, if you wait too long it then melts! (not good if that happens as there is that tell tale smell lingering on every meal for the next couple of days!, and comments of "you and your b****y projects and toys!!)

More cosmetic work, next are the seats. I tried making them from balsa, plasticard etc etc, but they just kept looking like homemade dolls house furniture. Now, one of my stupendous moments, I took a visit to a couple of car boot sales, and got hold of a plastic kids dumper truck for a couple of quid. I had looked for something with the correct size, and shape seats in the cab. Originally I wanted both forward and rear facing seats, and got to work cutting out the seats from the toy truck. I then stuck them back to back, and vac formed a few sets (told you it was easy, if you do it, you end up vac forming all sorts of useless things just for the practise, all of a sudden Easter eggs have a new lease of life,, well at least the wrapping does! ).

However, I decided to use just forward facing it seemed to look better. For the seat mounts, I made rails from balsa, but they didnt look quite right, and I kept studying pics on google images and like the sort of retro early style of seats that where on there, so in my second stupendous moment, I used the plastic things that you get from an old fashioned chandler, that you poke a towel into to keep it on a wall, if you know what I mean. Painted in humbrol chrome, and glued in place. The driver seat is on velcro, I take it off to get the cover off the motor

Huntsman logo was from Barry Sullivan model lettering, I sent him a pic of the font, I made the bugle/horn shape that goes behind the lettering from the sticky back plastic used previously. Nav lights fitted (chrome plated of course , a cabin light has been fitted, Fairey flag from BECC, and you see that the vents are now white, wating for new chrome alclad painted ones, put on with thin double sided tape

[Bradley]

Enjoying your build thread enormously, Paul.   I would appreciate a photo of the rear underside of the boat showing prop, etc., if you have one.

When you have time can you go into more detail about the vacforming as I think that I must have a go at it.

Derek.

[red181]

So on with the running set up.

Well, the shaft was bent, it would appear that the torque of the motor was creating some sort of whip effect, to the end of the shaft protruding after the gear and motor mount. It was a real bad job to get it off, as it had been slipping quite a bit (good news being some of that all important speed was being lost ). The shaft was badly scored, and the aluminium motor mount had been fooling me regarding the motor temp, it was running hotter than I had thought as the mount had been acting as a heatsink. This was found out by accident, after a run, the motor was felt to be cold, but I was only handling the motor can. 10 mins later I held the mount, it was still very warm!, so the 52.5mm "x" prop was too big for this set up, for now!

We decided to change the shaft to 5mm, but keep the original outer shaft to avoid changing it and having to reset the drive train. This meant that SHG where called upon to supply new bearings, (see page 45 of their catalogue  http://www.shgmodels.com/acatalog/). We changed to glacier bearings, oil/water lubricated,  they look like a sleeve going on the shaft, top bearing was a closed ballrace, new ballraces (x2) in the mount, and then an additional support to the end of the shaft, again ballraced. The gears where drilled and tapped so now using 3 grubscrews instead of 1 on the motor gear, and 5 on the shaft gear, this set up was not going to bend or slip anymore!
Thank goodness for Peter my craftsman, I was close to forgetting the whole thing, but glad he pushed me on, and did the drilling, tapping, bearing fitments, and made the aluminium support for the shaft (Ta mate!! )

There has been some science applied to the findings, I can recommend if you are testing, don't go alone, another pair of eyes are very helpful to document, film, photo and advise (remember the water tube being left off, would not have happened if I had a sailing buddy!) Peter has a hand held GPS, very small unit, size of a mobile phone. We put this in the boat on most of the tests, on my previous Fireboat build it was invaluable to achieving the set up. It records a number of positions, set by the user, and "flags" them on a file compatible with Google earth. When uploaded to Google earth, you see the flags, the time of each flag, numbered, and the speed (user set up parameters) so there is no guess work. How many times have we said to each other "well it looked faster!". Unfortunately you cannot see it from the attached photo, but we are able to see if the boat is accelerating quick, is the top speed dropping off, and what specific changes are made when swapping the props (remember I said how important the prop is!). I have a hand held digital temp sensor, so could record accurate temp settings, and we also had an ammeter to record amp draw holding the boat. Using this information, its easy to determine what set up is the best, assuming that the time is recorded when changing props etc.  

I also had access to my several props, and pictured is a sample of the different styles we tried. If you are in a club, beg or borrow a loan of different props to test with before going to unnecessary expense, I think at one point I had the loan of props off 5 different boats, excluding my own!

The google earth map shows how rubbish I am at getting a straight line!