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[Martin13]

                           This is all good – “GOOD CONSTRUCTIVE COMMENTS”
Food for thought Martin   one of the good sides of a Forum is ‘You meet people from all over the world’ but this does have a drawback.

When people give advice; the people giving the advice don’t know the capabilities of the person receiving the advice – How true and, this was the case when I was giving you advice about your hull build.

If we had known each other personally, I could have assessed/known how good of a builder you are. Must admit John, even I was surprised how well the hull turned out.

This may have altered your thoughts on your build.

When we first discussed diagonal planking; and the materials to use and the procedure to use; I for all my sins have to be excused because I took you as a complete novice. When I posted that thread re “Fibreglassing a Hull”, it was because, this is how things are done these days. The procedures for building and materials have changed over the last 30 years since I last built a hull. Having said that, I asked questions as a Novice would, hoping that I would get clear and precise instructions on the best way to proceed using todays methods and you VERY willingly provided such information with NO obligations  and am very grateful for you in doing so    I was expecting the planking to have some unevenness I do have some and also to have a certain amount of large gaps –no gaps just shear luck WRONG!!!!!   So here we go, this is for anyone else who is interested also.

First of all, think of the material that you are going to be planking with; in your case it was 1/16 planking.  This doubled up for the two skins and equates to ⅛ inch thick hull.The material I used doubled up to 1.2mm which I believe made it just over 1/16th    When we look at this and think about the strength of this actual build – you have produced a very, very strong hull – near enough ‘bullet proof’. I wouldn't go that far but strong none the less

This is because of the makeup of the actual material you have used and also the way you have applied it.

I bet now, if you took the boat, you could literally bounce this then youacross a concrete floor without any damage DON’T TRY THIS THOUGH  proceeded to coat it with another extremely strong material – woven roven or woven matting – and coated that in resin.

Now, if we can stop there and just think about why we are using the woven roven in the resin; because it is going to increase the strength even more to a hull that doesn’t really need strengthening any more.   What we should have done is, just give the hull two or three coats of epoxy resin.  Not polyester resin, but, epoxy.

This epoxy would have penetrated the first layer of your hull’s outer layer of plywood planking ONLY to the glue bond of the plywood.

Effectively it would create a good true seal from exterior environments.   This would have been all that would have been required on this type of hull.

Sorry my mate, but don’t bother trying to remove what you have already done.   Dress it up as per plan; and you are going to have a slightly heavier hull – but, immensely strong!!!! Actually the hull with the glass on it, is still lighter than the Mk 1 hull as I used to build a long time ago – SEE – your method has worked

Nothing to be sorry about John, as it was still my decision on how to proceed. When one asks for advice, it is up to that person as to whether he/she uses such information. You provided an idea and I was keen to try it out having never constructed in this method before.
So, DickyD thanks for your support but if John thinks he had upset me with those comments NO WAY. It is those type of comments I seek on this Build Thread – Good Constructive Comments.
The comments can only help me with my build and can be a guide to the Newbie along with other modelers having similar problems/mishaps.
So, having said that – Keep It Coming – I Love It.

Martin doon under

[Martin13]

Apologies to the forum – as stated earlier, I have proceeded with this build further than what is currently posted and hope today to bring it up to current status.

Fibreglassing – Before I precede, a little explanation about the choice of fibreglass. I made the decision to use 185gsm woven roven fibreglass as this was recommended by the supplier of where I got my materials and by club members stating that their will be less sanding required if I used this material over chopped strand matting. I also felt that the hull needed to be glassed over as the total thickness of planking was 1.2mm or 1/16th to 3/32”
When originally discussed with Bluebird re fibreglassing, I believe there was a misunderstanding on MY behalf as to material – I put this down to that fact we live in different countries and in some cases we call things by different names. We live and learn.

For the novice like myself, when it comes to fibreglass, I do not recommend using this type of material – you would be far better off using matting and more sanding, but at least have a better finish.

When I tried to cut out the 4 panels of glass, the damn material would not stop fraying – I had strands everywhere and found it almost impossible to have clean edges.

The two bottom panels went on with ease with roughly ½” overlap at the keel and about the same on the sides of the hull. The two side panels went on quite well with also about the same amount of overlap, but then I noticed something.

The side of hull where it meets the bottom ( chine stringer), the Fibreglass appeared to bulge out slightly ½” from the hull and regardless of my efforts, could not get it to sit down correctly. This happened on both sides of the hull from the transom till about 2/3rd along the length of the hull. The rest of the hull turned out okay with regards to no ripples or air bubbles, although the problem with strands was still evident – I had them everywhere over the hull.

After one week of pondering what to do, it was evident that the hull edges will need to be sanded

The build is now at its current status – I have just started to sand the hull where the glass bulged out.

If you look at the close up, you can see what I mean…Ho Hummm

Martin doon under

[Martin13]

more pic's - the glass over the keel is okay, light reflection - look along the edges - also note the strands everywhere

Come on you experts - please comment :) :)

Martin doon under

[tigertiger]

Another great thing about this site, and this is part of the nature of forums, even if the advice given is not needed by the builder it helps others with less experience.

I have learned so much on this site.

[Martin13]

Another great thing about this site, and this is part of the nature of forums, even if the advice given is not needed by the builder it helps others with less experience.

I have learned so much on this site.

TT
Glad to see that you are enjoying the build. The idea of this thread was to show others especially Newbies that when things go wrong, don't despair, as their are experienced builders on the forum to help you out - You Are Not Alone

Besides, we all stuff-up, I'm just proud of mine
Feel free to comment anytime TT

[Martin13]

Big day today at sanding hull. I have sanded one side of hull to remove defective fibreglass and have since learned that the fibreglass material I have used was far too heavy - a much lighter material would have been more appropriate. Unfortunately, I needed to sand through the glass and actually exposed the Plywood planks - now the end grain is exposed one more time - need to seal this.

With regards to planking. In hindsight, I now feel that I would have had an even better finish of the planking if I added more intermediate stringers of say 1 inch apart. I had another look at Bluebird's Whaleback build and noticed that John had his stringers much closer together - much better idea as this will give the planks more support and less likely to get dips or hollows in the hull.

My model as I sand, have noticed that I still have some dips in the planking which will need filling with maybe a mixture of resin and talcum powder, then resanded - and I dislike sanding.

Does this sound like the way to go ??

Martin 

[tigertiger]

Try and find David's Isopon P38 car body filler.

Available globally, and is designed to be sanded, so is softer than wood, unlike other car body fillers.

[andi4x4]

There is also an "Easy Sand" version of the P38 - certainly available in the UK in a tube and I think a tub. This is somewhat easier to sand than the regular P38 and may be more suitable ? I use it quite a bit for almost andy job that requires a filler.


Superb build Martin !  Makes mine look like an Airfix kit !

looking forward to seeing some more progress !

[Martin13]

There is also an "Easy Sand" version of the P38 - certainly available in the UK in a tube and I think a tub. This is somewhat easier to sand than the regular P38 and may be more suitable ? I use it quite a bit for almost andy job that requires a filler.


Superb build Martin !  Makes mine look like an Airfix kit !

looking forward to seeing some more progress !

Thanks Andi. Glad to see your enjoying the build and hope you can pickup tips of what NOT to do.
I managed to get hold of some body filler equivalent to P38 here in Oz. The company assured me it will do the job fine as its easy to sand and designed for the Auto industry to touch up scratches and pin hole dents. Have tried it out today and working fine - I still have a lot of sanding to do. I knew their was something I didn't like about building hulls

Listen, your model is no Airfix kit, it's the normal scale one usually builds MTB/PT's. My eyesight ain't what it used to be, so my theory is "If it's big, I can see it"

Martin doon under

[freelance]

Greetings from Canada

You appear to be open to suggestions...
Here is a tip that i learned from my 40 inch ELCO. I found that despite the single motor, the model planed beautifully but when i turned too hard the model would dig in and the speed would of course drop fast, to eliminate this I glued blocks onto the transom as to limit the movement of the rudder arms to approx 30-40 degrees, now no matter how hard i turn the model has its own turning arc and much less stress...of course it is a wider turning arc but there is a price to pay for all decisions..

HTH

John

[Martin13]

TIP OF THE DAY

Whilst sanding fibreglass - was hands BEFORE you go to toilet ::)

Martin itchin doon under

[Martin13]

Thanks Freelance for the advice, will keep that in mind.
In using P38, I have not yet mastered the skill of not putting on too much - hence even more sanding to do.
I have almost completed all sanding to the main area on the hull and successfully filled all hollow areas. The only problem I have now is that I got slightly carried away when sanding and have managed to put a radius on the chine line from the bow to about 8 inches back (see photo's).
Have been advised to build up chine line with P38 and sand to correct shape. This I will commence in the next few days...

Martin doon under

[andi4x4]

Looking good Martin !

Boy - do I wish I had a workshop that big  :( :( :( :(  mine is also the office and is about 6'x10' !




 :( :( :( :( :( :( :(


regards

Andi

[DickyD]

Looking good Martin !

Boy - do I wish I had a workshop that big  :( :( :( :(  mine is also the office and is about 6'x10' !




 :( :( :( :( :( :( :(


regards

Andi

Your office is a lot larger than my shed, plus you've got carpet.

[andi4x4]

Your office is a lot larger than my shed, plus you've got carpet.
[/quote]

Ah - Carpet - so that'll be that coloured fluffy thing on the floor that the missus keeps moaning about then ! 


Regards

Andi

[Martin13]

Looking good Martin !

Boy - do I wish I had a workshop that big  :( :( :( :(  mine is also the office and is about 6'x10' !




 :( :( :( :( :( :( :(


regards

Andi

Good one Andi, we live on a fairly large property and have a bit of room. A mans shed is his domain and I wish my workshop was as tidy as yours. The centre bench where I'm building the hull  measures  6' x 12'. Actually the shed is 20' x 40' and I have another at right angles the same size. :)

Having said that, because I have the room doesn't mean that I am a better modeler. In fact, looking at other peoples builds, it appears the smaller the workshop, the better the Model - just look at DickyD:'( :'( :'(

Martin doon under

[andi4x4]

 Lol,

 The only reason mine is tidy is because I wouldn never find the door out ! It is actually a bit messier in that pic than I would normally have it.

As for the smaller the room, thebetter the modeller - I think I had better move into the cupboard under the stairs then ! 

Regards

Andi

[Martin13]

Lol,

As for the smaller the room, the better the modeller - I think I had better move into the cupboard under the stairs then ! 

Regards

Andi

Andi, there is one advantage to a large shed, whenever I have visitors the model is usually the last thing they see and in some cases, NOT at all.

Martin doon under

[tigertiger]

Topic split and moved

As much as I also love the Quatro, I have created a new thread Audi Quatro and Other Cars and moved this discussion to other hobbies and interests

Now back to HMS Brave Borderer.

Thanks
TT

[Martin13]

After sanding all weekend, I have started on the Chine Line repair where I inadvertently put a radius after some vigorous sanding. Still applying more P38 than I really need, but "what the heck".

Photo shows one side completed - sort of :-\

martin doon under

[Martin13]

To be honest, its actually better to put on too much body filler as I found it far easier to gain correct shape and fair in.
Quite pleased with filler repair on Chine Line  :) :)- Line now has a definite edge and faired in well near the bow.

Finally got it right :) :) :)


Martin doon under

[andi4x4]

Topic split and moved

As much as I also love the Quatro, I have created a new thread Audi Quatro and Other Cars and moved this discussion to other hobbies and interests

Now back to HMS Brave Borderer.

Thanks
TT

 Thanks Tiger,

 I have followed up with it on the new location !

Regards

Andi

[andi4x4]

To be honest, its actually better to put on too much body filler as I found it far easier to gain correct shape and fair in.
Quite pleased with filler repair on Chine Line  :) :)- Line now has a definite edge and faired in well near the bow.

Finally got it right :) :) :)


Martin doon under

Looks good Martin !  I have a fibreglass hull on mine, and I must admitt that the chines are not as sharp as I would like - I may consider doing this with my GRP one.

Regards

Andi

[Martin13]

Now that the Chine Line is correct and hull sanded, I have applied two coats of pure resin.

After the pong dissipated, I have placed the hull over the bath tub (won't fit in) to allow the resin to fully cure for the rest of the week. Next weekend if all goes well, will start final sanding before priming hull :) :)

Martin doon under

[Martin13]

Been a while since I last posted but this is a SLOW build.

After the two coats of resin applied and dried in the bathroom for a whole week, I started sanding again using 80 Grit Emery Paper followed by 120 Grit. This was followed up with 180 wet and dry on a wetted hull and gradually worked my way down to 600 Wet and Dry. Believe me, this took a few weekends to achieve before I was happy with the result.

In trying to work out motors, ESC's, batteries etc - FLJ has suggested a fit using his P94 setup but I keep changing my mind re motors - it appears I cannot choose a motor to start with..I gave up in total confusion and decided to leave this part till I have installed the prop shafts and rudders.

Prop Shafts - I must give a big thankyou to Bluebird in working out the correct location for shafts and rudders. I need prop shafts at least 15 - 16 inches long and am currently having them manufactured by Float-A-Boat here in Oz.

Spent all day Saturday in working out prop shaft locations and drilling hole for Center Prop Shaft. Now any decent modeler would have built the slot in the keel during build but I was unsure of it's exact location. Luckily, I had some long shank drill bits but I still took my time and re-measured many times before commencing.

After the centre prop, I also drilled and filed the outboard prop locations including holes for rudders. Had to slightly modify one of the internal formers to allow clearance for shafts.
I then made up a jig to hold props in correct position/alignment - not quite right yet as the starboard shaft needs to be lowered a little more.

If you look at the inside shot for propshafts and rudders, you will see that I need to add extra material at hull entry point to beef up these areas, probably next weekend...

Martin doon under

[Martin13]

Forgot the inside hull shot..

Martin doon under

[bluebird]

Hi ya there my mate Martin Doon under

Speed building causes many mistakes - so, as you are doing, take your time.   The build is looking very good at this moment and as far as re-enforcing around your propeller and rudder shafts you have two options; around the rudder posts you could put plywood of approximately 1/8 inch thick and about 1 inch x 1 inch square epoxied into the hull - and this would spread the load.  The same with your two outer prop shafts.   But, we are not building a super-duper light weight extremely thin hull here; and we are not going to apply vast amounts of stress to the propeller shafts or rudders, through using high performance motors.   So, if you wanted, you could bond the prop shafts and rudder tubes in with car body filler; feathering the edges of the body filler out, along the inside of your hull.   This may be an easier option;

the other thought I have, in your photographs are these prop shafts and prop tubes you are going to use on your final build?   If so, dont forget to cut them to length required before you bond them in 

John

[Martin13]

John, Thanks for that mate.

I think I feel more comfortable in placing ply around rudders and prop shafts for reinforcement seeing that their are only two layers of 0.6mm ply.
The prop tubes in the photo are only their for fitment indications ie, see where the prop tubes end up. The center shaft is only 14 inches long and will receive longer shafts later this week.
My only concern is that the center prop shaft is only about 1/2 inch above keel. I will need to place some ply in the hull to mount the motors (and probably on aluminium brackets) and would like to have clearance from the hull for air flow and water cooling coils.

The motors I am currently looking at are the Graupner 700BB Turbo's (7.2 - 19.2v) and MFA 850's which will be powered by a Gel Cell.
I am also investigating the "Darke Horse" Speed 700, 3:1 Ratio Planetary Marine Motors (high voltage, low current drain). Apparently, these motors are suited to this type of model and can operate from 6V to 28V using up to 20 Nimh Cells.

Electronics, will probably use ACTion's P94 setup but if this turns out unsuitable, the unit will be ideal for my 2 shaft Freemantle Class Patrol Boat (arriving shortly)..

I think I will be a lot happier to have the motors in hand so I can determine final length and placement of prop shafts before I set them in permanently...

John and forum members, please feel free to comment - it's all helpful and appreciated

Martin doon under

[Peter Fitness]

Martin, that looks great. Now I'm back home, I'll soon be getting back in my shed and building again. I had intentions of building a Grand Banks cruiser, followed by an Armidale Class patrol boat, but arrived back with a Billing Nordkap kit. As I have not tried plank on frame construction before, I thought that this kit may be a good introduction to the technique. I guess I'll just have to live a couple of years longer to fit the others in 
I look forward to more pictures of your Brave Borderer build.
Peter.

[banjo]

 
Cooling Coils.....
If you are a bit pushed for space there are cooling gizmo's that sit, saddle like, on the top and sides of the motor.  I got a couple for my Fire/Crash Boat.
They are in the catalogue at ASTEC.

Its a great boat you got building there...

 :)

[banjo]

 :)

Cooling Jacket at :- http://www.astecmodels.co.uk/products-big.php?gref=g3326.jpg

[Martin13]

:)

Cooling Jacket at :- http://www.astecmodels.co.uk/products-big.php?gref=g3326.jpg

Banjo, thanks for the info, clever little units. Hopefully by Friday I will receive my prop shafts in the mail. I will sit them into position and see what clearance I have with that center shaft - may have to sit the center motor a little further back than the outer shafts.

On the weekend I hope to start making the "P" Brackets. Currently, I have a friend drilling the 8mm holes in the 13mm shaft housing - much easier and accurate on a lathe. The upright part of the bracket will be made from 3mm brass flat bar - this is going to be a pain in the butt. I have a steel cut-off saw - I hope I can use that - better than a Hack-Saw.

Peter, glad to see you finally made it home and ONLY one kit?? Plank on Frame - I had a lot of fun with this one, but alas, it is and will be a slow build.. Ho Hum

Martin doon under

[Martin13]

Hi All,

Back for a quick update on a slow build.

Longer prop tubes arrived but alas, center shaft still too short. I have now ordered 1 shaft with a tube length of 520mm as I figure that I can always make it shorter.
Motors - finally decided on the "Darke Horse" Speed 700, 3:1 Ratio Planetary Extra High Performance Low Inertia Marine Units (phew, that was a mouth full) and they arrived today with cooling jackets fitted. Also included a great set of instructions, heavy duty couplers, water pickup tubes and other bits and pieces. These motors have a voltage range of 6V - 28 V and I intend to run on 24V.

I have a CD of a 1:24 Perkasa with 2 of these motors and the boat was literally flying.

"P" Brackets. Managed to cut these out of 3mm Brass flat and have used CA glue to temporarily hold together for shaft alignment etc. When I am finally happy with shaft locations, motor mount setup and alignment, will have them silver soldered.

The pictures below show the tubes, props and "P" Brackets assemblies including the center motor aligned with a Brass tube cut to the length of 520mm just to see if I have enough clearance. The P & S motors will be set forward of the center motor

Martin

[bluebird]

G'day Martin

The build is coming along fine    my apologies Sir, for getting the length of the centre shaft wrong - but, it is very difficult to see a ruler from 13000 miles or so away, even though I do admit to having the plans in front of me  as a thought though - ALL IS NOT LOST - instead of purchasing a longer centre shaft; you could put an intermediate shaft in - where you have a solid coupling between your propeller shaft and the intermediate shaft - following by a thrust bearing mounted on a bulk head.  Then, on the end of that, where the intermediate shaft comes through the bearing - you could then have your muff coupling connected to your motor.  The length of the intermediate shaft would equal the length you require to move the motor back to give you the correct height and angle.

The other thing I would add, as an alternative, to the way you are building your 'P' brackets - where you have your baseplate fixed to the upright on the 'P' bracket you could dispense with this for the time being and manufacture the 'P' bracket say 3/4 inch longer so therefore the upright would have to go through the bottom of the hull in a pre-cut slot.   Leave this unglued until you have set your prop shafts into the hull at the correct angle - then epoxy on the inside - the 'P' bracket upright.  This will give a lot more strength & a lot more load displacement.   When the epoxies have all set, you could then cut a slot in your base plate and reposition this over the upright and the 'P' bracket and the remaining bit of the slot as visible could be 'filled in' with car body filler to camouflage the slot.

The third thing I note is that you are not cutting short your propeller tubes.  On the original vessel; the propeller tube only protruded from the hull 6 - 7 inches so in scale this would be about 1/2 inch.  Then the propeller shaft itself runs unprotected and open to the environment until it reaches the 'P' bracket where it goes through a set of bearings and then to your propeller.

Food for thought.

aye
john e
bluebird

[Martin13]

G'day Martin

The build is coming along fine    my apologies Sir, for getting the length of the centre shaft wrong - but, it is very difficult to see a ruler from 13000 miles or so away, even though I do admit to having the plans in front of me  as a thought though - ALL IS NOT LOST - instead



The third thing I note is that you are not cutting short your propeller tubes.  On the original vessel; the propeller tube only protruded from the hull 6 - 7 inches so in scale this would be about 1/2 inch.  Then the propeller shaft itself runs unprotected and open to the environment until it reaches the 'P' bracket where it goes through a set of bearings and then to your propeller.

Food for thought.

aye
john e
bluebird

No need to apologise John, even I didn't get it right. Only last night have ordered a much longer center shaft (this will be the third one). Also have been advised by the motor supplier that the shaft itself should be 5mm, then machined down to take 4mm prop.

These motors I am installing may load up the shaft at 24v and with the center shaft being so long - need to go heavier. I did think about intermediate shafts but cannot even get a single shaft the correct length. No worries about all the shafts as I am sure they will come in handy some day.

Your third point, can I please have a sketch - I'm a bit THICK tonight

Martin doon under