Winchelsea false keel & bulkheads

[CaptnBirdseye]

Hi guys

Has anyone this side of the pond (UK) used the 6mm lite ply from Cornwall Model Boats for their keel and bulkheads?

Or, does anyone think it would be acceptable and up to the job?

Here is the link:  https://www.cornwallmodelboats.co.uk/acatalog/Lite-Ply-Sheet-6mm-x-600mm-P5521188.html#SID=2043 

They also supply in 900mm lengths (for the false keel?). Not really much info on their website so thought i would ask.

Cheers

Gray

[Matt D]

Hi Gary.  I can't answer your question about the 6mm lite ply.  But regarding the false keel: it's designed in 3 pieces and shouldn't be built as one piece.  The main reason is that it will tend to warp if it's not broken up.  In fact, the middle piece is also reversed to negate the effects of any warping that might occur. 

 

One word of warning I will offer is to make sure your printout is done a 100% scale, not "fit to page".  I have a second Winchelsea bulkhead set that's about 96% scale from learning that lesson the hard way.

[allanyed]

Are you speaking of the false keel which is the thin (6" for a 36 gun) strip attached to the underside of the keel or the keel itself?  If the keel itself, based on the Shipbuilder's Repository 1788 for a 36 gun British ship it was 1'3" square at midships and tapered to be sided at the stem and stern post 1' 0"  This tapering may expose layers of the plywood.  The tapering of the stern post and head are even more pronounced so there will surely be one, maybe two layers of plywood exposed which is not a great look.  Other than for the bulkheads, you may want to consider using solid material rather than plywood for these various pieces if you are going to shape them for a more realistic look.  The tapering of the head is shown in the following build log. It is a different ship, but same idea applies. 

https://modelshipworld.com/topic/33157-rattlesnake-by-ed-ku20-model-shipways-164/page/3/#comment-978894

Allan 

[Matt D]

Allan, no.  This is the bulkhead former of the plank on bulkhead framing.  Chuck’s design has that piece built up out of three pieces with jigsaw mating.  You can see it on the first page of nearly every Winchelsea build log.  Here is my own:  

 

[CaptnBirdseye]

4 hours ago, Matt D said:

Hi Gary.  I can't answer your question about the 6mm lite ply.  But regarding the false keel: it's designed in 3 pieces and shouldn't be built as one piece.  The main reason is that it will tend to warp if it's not broken up.  In fact, the middle piece is also reversed to negate the effects of any warping that might occur. 

 

One word of warning I will offer is to make sure your printout is done a 100% scale, not "fit to page".  I have a second Winchelsea bulkhead set that's about 96% scale from learning that lesson the hard way.

Hi Matt, thanks for the reply. No, I was thinking of the cost vs the 600mm one.

Have checked the plan measurements and the scale box measures 4 quarters to the inch. So fingers crossed there.

[CaptnBirdseye]

17 minutes ago, allanyed said:

Are you speaking of the false keel which is the thin (6" for a 36 gun) strip attached to the underside of the keel or the keel itself?  If the keel itself, based on the Shipbuilder's Repository 1788 for a 36 gun British ship it was 1'3" square at midships and tapered to be sided at the stem and stern post 1' 0"  This tapering may expose layers of the plywood.  The tapering of the stern post and head are even more pronounced so there will surely be one, maybe two layers of plywood exposed which is not a great look.  Other than for the bulkheads, you may want to consider using solid material rather than plywood for these various pieces if you are going to shape them for a more realistic look.  The tapering of the head is shown in the following build log. It is a different ship, but same idea applies. 

https://modelshipworld.com/topic/33157-rattlesnake-by-ed-ku20-model-shipways-164/page/3/#comment-978894

Allan 

Hi Allan.

Sorry I guess I’m not making sense. I read in a build diary that Chuck recommended 6mm lite ply be used for bulkheads and false keel. I just wondered if anyone had used the ply supplied by Cornwall Model Boats 

I had an idea to try making my one as the cost to import from US is very high. If I mess up THEN i can buy some from Chuck 🥺

Edited April 11, 2023 by CaptnBirdseye

[Jaager]

I don't think in metric  for length or weight  but  I was thinking 1/4"  and a G search for 1/4" AA Birch ply revealed that 6mm is ~1/4"

I would try to find some AA Birch ply.  Mainly because it is the mostly likely to be flat and stable.

 

I saw that over here HomeDepot has a 4x8 sheet for~$50  and Lowes has 2x4 sheet for $22  - so buying the 4x8  gets you 4  2x4 sheets for~$13 each,  HDs have a vertical jig with a crosscut saw and probably do one or two cuts for free.  HomeDepot is where a lot of contractors buy so  maybe your contractor suppliers may not try to pay off their mortgage by selling one piece of wood like some of your dealers seem to be like.

 

If the developers of POB had used descriptive instead of hyperbolic terms for the two key parts - much misunderstanding could have been and be avoided.

'Central spine'  or just 'spine' is what is often called 'keel'  or 'false keel' in POB. 

'Mold/mould'  is what is called 'bulkhead' in POB.   Steel ships have bulkheads.  Seagoing junks had bulkheads.  Wooden sailing ships did not have bulkheads.

 

If a "window" is cut in each mold P&S  at the same level  - after the molds are bonded to the spine - a wooden, or metal bar can be threaded on each side of the spine -  this should go a long ways towards stopping any scoliosis.

[Gregory]

Take your calipers with you when you buy plywood..  Last time I bought some 3/16 at HD it was closer to 5/32.  I tried to point this out to a supervisor/manager and just got a shoulder shrug, and a " That's what they give us. " .

[allanyed]

I think it is me not being clear, my apologies.  I think it is mostly a matter of terminology.  

 

The pic below should help a little even though it is not the same ship.

 

Allan

Edited April 12, 2023 by allanyed

[mtaylor]

1 hour ago, Gregory said:

Take your calipers with you when you buy plywood..  Last time I bought some 3/16 at HD it was closer to 5/32.  I tried to point this out to a supervisor/manager and just got a shoulder shrug, and a " That's what they give us. " .

Seems they quote the size before the factory sands it after everything is laminated.  I ran into this and asked and that was the answer.  So take your calipers and measure.

[Gregory]

Almost negligible, but It can make a difference when you are cutting slots for POB..

[Robere210]

3 hours ago, Gregory said:

Take your calipers with you when you buy plywood..  Last time I bought some 3/16 at HD it was closer to 5/32.  I tried to point this out to a supervisor/manager and just got a shoulder shrug, and a " That's what they give us. " .

I've been a woodworker for over 65 years.  I'm currently restoring a 1957 Higgins 17 foot Sport Speedster.  The Higgins is a plywood boat.  Yes, I know this is a model ship forum but I like model ships too.  Buying plywood today is a gamble at best, unless you want to part with some greenbacks, and I mean a lot of greenbacks.  I always keep my eyes peeled for houses from the 1950's that are being remodeled, and see if I can get any used plywood out of the refuse pile.  I've gotten some incredibly good plywood from old houses.  That said, I know you are talking about much thinner ply than I generally work with, but it don't hurt to chime in.  In boat building, I've also come across '50's plywood boat bottoms that have completely delaminated, BUT the wood is not rotted.  I've grabbed those too, as the wood is generally tropical species, and very rot-proof.  It is also nice and uniformly thin, at 1/16th to 3/32nds

[CaptnBirdseye]

Would 'Laser Grade Poplar lite plywood' be recommended? Sorry, but never bought my own before so all new to me 

https://www.sketchlasercutting.co.uk/products/6mm-laser-grade-poplar-lite-ply-wood-sheet-fsc?variant=29264387440714

 

They also supply 'Ceiba' and Birch.

Edited April 12, 2023 by CaptnBirdseye

[Matt D]

1 hour ago, CaptnBirdseye said:

Would 'Laser Grade Poplar lite plywood' be recommended? Sorry, but never bought my own before so all new to me 

https://www.sketchlasercutting.co.uk/products/6mm-laser-grade-poplar-lite-ply-wood-sheet-fsc?variant=29264387440714

 

They also supply 'Ceiba' and Birch.

I think this would work fine, Gary.  As Gregory noted above, the slots are the area that is most affected by the thickness.  Once you have the bulkheads cut accurately, the thickness isn't very critical.  Be sure to transfer the marks for the gun port sills to the plywood as accurately as possible.  This is a fantastic project and we'd love to have you join us in building your own Winnie.

 

One last thing to consider: are you buying the laser cut chapter sets from Syren and having them shipped to you?  If so, then the incremental cost of adding the laser cut bulkhead set may be worth considering.  I don't know your experience level with a scroll saw.  I thought I did a really good job and then found out down the road that I would have been much better off buying Chuck's.  Unless you're scratch-building the whole thing, it might be worth shelling out the dough for the laser cut set.  Please don't take this as discouragement if that's what you really want to do, because I understand that as well.  I really wanted to cut out my own bulkheads.

[CaptnBirdseye]

1 hour ago, Matt D said:

I think this would work fine, Gary.  As Gregory noted above, the slots are the area that is most affected by the thickness.  Once you have the bulkheads cut accurately, the thickness isn't very critical.  Be sure to transfer the marks for the gun port sills to the plywood as accurately as possible.  This is a fantastic project and we'd love to have you join us in building your own Winnie.

 

One last thing to consider: are you buying the laser cut chapter sets from Syren and having them shipped to you?  If so, then the incremental cost of adding the laser cut bulkhead set may be worth considering.  I don't know your experience level with a scroll saw.  I thought I did a really good job and then found out down the road that I would have been much better off buying Chuck's.  Unless you're scratch-building the whole thing, it might be worth shelling out the dough for the laser cut set.  Please don't take this as discouragement if that's what you really want to do, because I understand that as well.  I really wanted to cut out my own bulkheads.

I hear ya! Scroll saw experience - vertually nil but willing to give it a go lol. I've priced up the wood package from Vahur at Hobbymill.EU, but undecided which way to go yet. I've also got Cheerful in my stash and just received the wood package from him (Vahur). This is more of 'in the planning' stage at the moment. I've so far: downloaded and printed plans...and er thats about it so far 😬

[mtaylor]

It might be worth your time to see if there's any local hobby shops in your area that specialize in RC aircraft (seems most have gone that way).  They do sell lite ply for those building A/C.