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I am applying cypress planking on my USS Constitution hull and it goes on nice and even but after the glue has dried the surface is very uneven. I am using Weldbond white glue. I don't know if the glue is causing the wood to swell unevenly or not. post-10594-0-28018500-1456943002.jpegpost-10594-0-41609200-1456943040.jpegis anybody else having this problem? If so what have you done to correct it?

Edited by Burroak
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Bruce I cut the strips on my Byrnes mini table saw and when I apply the strips they are nice and flat but something is happening during the drying process. I don't know if I'm using too much glue or maybe it's the wood itself. I laid the deck planking using the basswood that came with the kit and had no problem at all.

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Unlikely that the glue is causing your problem, I suspect that it is a temperature or moisture change. Cause, wood not cured, sawed but not sized after curing or you are adding moisture as a bending aid. Don't sand anything until you find out why you are having this problem, sand it now to fit, and the wood dries further it will shrink, your sanded to match high planks will become the low ones.

jud

Edited by jud
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I'm wondering if the plank isn't tight against the bulkhead.  White glue (PVA) is quite viscous, so if the clamping pressure isn't high enough to squeeze out the glue then plank and bulkhead won't come together.   Other makes of glue, such as Titebond, are much thinner.  

 

I'm not sure of the chemistry of PVA glue, but I think you can water it down (only very little water is needed) to thin it out.

 

As a test, lay some strips on a flat surface at the distance of your bulkheads.  Then glue a few planks to the strips.  With some, apply the same clamping pressure as was used on the model, and on others, use a c-clamp or heavy weight.  

 

FYI, with white glue you should coat both surfaces, but you only need a transparent coat - just get the wood uniformly wet.  If you can't see the wood color through the glue, you've put on too much.   For furniture making, the thinner the glue line, the stronger the joint.  It also means there is less squeeze-out glue to clean up.

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Are you sure you want to use cypress?  You might be happier using Hard Maple.  It is more work for a cutting edge and a disk sander or table saw will burn the face if you are too aggressive.  But it takes more work to overdo a cut, is much stronger,  has a wonderful surface to finish and does not move so much with humidity changes.

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Jaager I think you're right about the cypress. I'm a woodworker and I picked the cypress because I had some laying around. It looks nice after I mill it and even when I glue it in place, but during the drying process it moves at different rates so it becomes uneven. I think I will finish to the top of the wale with the cypress and then change wood. The ship will be painted but I still want the wood to look nice so it doesn't telegraph thru the paint. Thanks for your input.

 

Greg H.

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I am applying cypress planking on my USS Constitution hull and it goes on nice and even but after the glue has dried the surface is very uneven. I am using Weldbond white glue. I don't know if the glue is causing the wood to swell unevenly or not. attachicon.gifimage.jpegattachicon.gifimage.jpegis anybody else having this problem? If so what have you done to correct it?

I had a similar problem when using Titebond even though I use hardwoods on my ships. I started using Aleene's Tacky glue and it was less problematic pus it has a better initial hold. Might be worth a try. good luck.

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  • 3 months later...

Greg,

 

The Byrnes saw is top of the line, but thickness of the planks can still vary.  Check with a micrometer or good caliper.  A thickness sander is a great  way to get the sawn planks to an even thickness +/- 001.  

 

If your kit supplied wood sat flat, I am sure it is not the glue thickness, at least not as much as you show in the photo for the cypress.  Could be cypress (first I heard of using cypress for planking) could be a lot of things mentioned here or a combination.   Again I would measure your planks; thcknesses first, then check that your bulkheads are fair.  If you still doubt the glue, any aliphatic should be OK.  That is what the majority of members here use I'm sure and it does not cause problems with the planking laying unevenly.

 

Allan

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  • 2 weeks later...
  • 3 weeks later...

I think I missed the problem that started this.

This looks like a POB build.

It also looks like Burroak is trying to get by with a single layer of planking.

My thoughts: in POB the molds are generally spaced too far apart to provide an unambiguous surface for the planking to lay against.

Wood is organic - it has inherent variability in response to stress.  The distance between molds gives the planking an opportunity to

display that variability.

I doubt that even the most precise thickness sander can produce stock without some +/- variability along and between planks.

The original shipwrights had to adz or plane the surface of the planking to get a smooth surface,  we should expect to do sanding,

or scrape, or plane.  It is probably wise to leave the planks a tad thick to provide something to remove without being able to read print

through a too thin final thickness plank.

The planking is going to react to changes in heat and humidity over time.  Without a near solid support and having been forcefully

clamped while the glue sets up, the planks are going to flex and swell at different rates.

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