Help needed with a boat table

[David Wade]

Thanks, Alan.
The truth is, I really have a lot to learn. After watching the wood cup so badly after crosscutting it, and then watching it straighten out on it's own, I thought that maybe laminating the two pieces together would help eliminate any warping or cupping of the finished project- maybe I should have asked that instead of my original question.

So- using only one layer of 3/4" mahogany, once I get it to the desired dimensions, add a reinforcement piece for the support pole hardware, and finish with epoxy, is there anything else I should/could do to ensure it stays flat?

Thanks,
David

[Alan Rutherford]

...After watching the wood cup so badly after crosscutting it, and then watching it straighten out on it's own, I thought that maybe laminating the two pieces together would help eliminate any warping or cupping of the finished project- maybe I should have asked that instead of my original question.

My experience with boats includes a lot of time on salt-water sailboats. Not much of that involved boat construction except for repairs and it ended a while back. Today I wouldn't know where to go to find someone with a boat big enough to have a table. I remember a lot of mahogany. I don't recall warping having been a problem although I don't recall a lot of wide unsupported panels of solid wood either.

My concern was with the appearance, not the construction, and it's not me you have to satisfy, it's the boat owner and yourself. I think laminating the two pieces would work structurally and you already have some good advice about doing that. You could taper the bottom layer to look less bulky and hide the seam. One consideration is that if someone falls into the table or climbs on it, you don't want it to split and the 2 layers would be strong.

As for the design, all this is my opinion. If you Google "boat tables" and look at images, you will find lots of other opinions and you probably should: The raised edges should be vertical on the inside and can be tapered on the outside. They should be tall enough so that the edge of a sliding plate doesn't slip over the top and launch the plate into the air. The corners of the table should have a significant radius to protect flesh from damage and the raised edges can stop short of the corners, making it easier to clean (and build). Those edges will also help stiffen the table top but you won't need that if 2 layers of 3/4". You'd have to be aware of differential expansion between the edges at the ends of the table and the board underneath.

I would have finished it with Varathane (polyurethane) which works but does not refinish well because you can't blend the edges between new and old finish. I hope there are better choices today.

[Tom Bender]

To clarify a detail in Alan's advice (Alan I apologize if I have this wrong) the raised edge must not be cross grained or it will cause problems.

Also, cauls are one way to go. Vacuum bagging may be better and sand bags work well also.

Not to throw water on a nice campfire, but plywood would be more reliable.

[Alan Rutherford]

To clarify a detail in Alan's advice (Alan I apologize if I have this wrong) the raised edge must not be cross grained or it will cause problems.....

In principle you got it right but there's no point having the raised edge only on the long-grain side. I knew less about things like differential expansion when I was involved with boats and wasn't looking for table details, but I think rails, cross-grain or not, were typically just glued and screwed and varnished solidly in place. Often that was on plywood but I can remember some tables that were not. You could use elongated screw slots. If neither the OP nor the boat owner care, I wouldn't argue for the raised edges. Some boats lead more tame and civilized lives than others.