Laminated table top

[mjmwallace]

Need help here as to whether or not this is a good idea:

Got a line on 1/2 inch maple that I thought I would laminate to some ply and build a table top for a crafts area the wife wants. Figured I'd join it with biscuits and glue/screw it on to the ply to come up with a 1 inch thick top. I'd mount it on top of a 2x4 frame. The top would span a wall in a small room in the downstairs, (a bit, just a bit more humid). The span is about 6 or 7 feet and the top would be about that with a depth of 3 feet.

However read in a mag that someone tried to do something similar and ended up with cupped boards. The recommendation was just to mount the hardwood to the frame without the ply substrate.

A 1/2 inch is not strong or thick enough, in my opinion for the top I want to build. So I thought I'd double up on the maple, in that I'd laminate two boards and then join the doubled boards with either splines or biscuits and then mount that to my 2x4 frame.

Good idea or bad? Alternatives?

Thanks

MJM

[Steve]

I'd cut the maple into 1" wide strips, then glue them up into a butcher block top 1" thick.

--Steve

[mjmwallace]

I would just buy a maple table top (Woodcraft sells them) instead. I can't think that the butcher block 7 x 3 would be cheap.

Thanks, tho.

MJM

[Tyke]

I made some doors, about 21in wide by 70 in tall by gluing 3/4 in think poplar to some birch plywood. The plywood was not quite flat. I made sure my gluing was clamped to a flat workbench. The result was the flatness I desired. I also tried to match pieces of the poplar which were bowed in the opposite direction to the plywood.

With 1/2in stock, you are more in need of the plywood to be flat, or else you will need to glue strips of the maple as edging to keep this from bowing.

If you have good surfaces for the maple and plywood (clean, no voids, etc.) then screwing and biscuits are not going to help with any future stiffness. I would only consider screws if you do not have enough clamps. If you have sufficient clamps, then once the glue dries, the screws would be redundant.

Biscuits would only assist in alignment. With 1/2in stock it would be easier to put weights on the strips to get them to align with the plywood. You may need some clamping side to side.

Grizzly also has maple laminate tops. If you are within driving distance, these are reasonably priced.

Dave Paine.

[Elrond Hubbard]

You'll get cupping if you only laminate one side of the plywood. The maple will expand/contract at a different rate than the substrate. So either:

A. Use Two layers of the maple, and skip the plywood, or

1. Laminate another 1/2 inch thick hardwood to the other side of the plywood. The same maple would be the best choice, but another hardwood would be better than any softwood, or nothing.

Feel free to ignore the voice of experience ;o)

Scott

[SCWAForum]

Scott,

Thanks much. I don't ignore opinions of people who have been there before me. Your advice sounds great!

MJM

[Joe Brophy]

[SonomaProducts.com]

If you have a router, you could put a tongue and groove edge on these boards, then mount them to ply with nails hidden in the grooves, just like flooring. I would use 3/4 ply for more heft and do something nice at the edges. This is how flooring is done and you won't get any cupping. The nails will float enough to to take care of that just like in flooring. Just make sure the edge detail allows for some movement.