1.5" solid wood over solid core door for benchtop

[Dennis McCullen]

I have a couple of doors that seem pretty solid and I've made one bench already topped with hardboard. My goal is to build a bench with a front and a tail vise. Rather than build a 3" thick top from narrow strips glued together, I'm curious if anyone has tried laminating a solid wood top approximately 1.5" thick SYP to a solid core door, yielding a bench top that would be hefty and 3.25" thick. Seems that the solid SYP would be a better medium for dog holes and such.
Anyone out there ever see this arrangement?

[Mike Kees]

I built a bench a couple of years ago to sort out how to build my "dream bench". For the bench top I used 3 layers of plywood 3/4 baltic birch on top,3/4 good one side and a piece of one inch all sandwiched and glued. this was easier than it sounds to glue up. I spread glue on one piece and screwed it to the top being careful to use screws that would not poke thru. After drying overnite I removed all the screws and repeated with the next layer. again remove all the screws. Rock solid, flat, heavy and thick enough for holdfasts etc. I thought about trying to glue solid wood on top but decided it probally would contract-expand more than the plywood. So I guess that I would either go all plywood or all solid wood. Plywood has worked very well so far for me. I also had a solid core door saved for the bench. It was leaned up against my wall ,now it has about a one inch bow. Not sure what your doors are made of,they could be better than the one I had. Good luck with whatever you decide,Mike.

[Jerry Miner]

Solid wood and plywood do not work together very well. The solid wood will be absorbing and releasing moisture as the humidity changes, and with a door laminated under it the top surface will be reacting to moisture changes differently than the bottom. It won't want to stay flat. And the lumber will expand and contract in a way that is different from the door. You could end up with cracks in the top unless you allow movement between the two materials.

I think you'd be better off going all-door (laminate two together for a thick top) or all lumber.

[lowell holmes]

Have you considered buying a laminated kitchen cabinet top. They work well as a bench top.

[Robert Engel]

I think Jerry brings up a valid point. That being said, if your shop is climate controlled & the wood is dry and well acclimated, I don't think the issue is as critical.

If the wood is subject to climate variations, I would either figure out a way to attach the wood without gluing, or laminate two doors together.

FWIW, most solid core doors I've dealt with have particle board between the veneers, so I would add a dog hole strip of solid wood.





I wouldn't use wide boards concern would be cupping.

[John Blazy]

By using the door as a spacer core, you are essentially making a Torsion box, which is good for bench tops. Personally, I would glue 3/4" shop grade birch plywood onto both faces of the 1-1/2" door, and glue .060" HPL ("Formica") onto the top face for a ton of reasons. Then edge the entire bench top in solid beech. This is almost the way I made my bench (same but without the door core). I didnt plan to enter my bench into any shows, so I went for utility. The solid beech edging is the traditional wood for benches, and I wanted the HPL on top for ease of removal of glues and finish drips, as well as its solvent resistance. Then I drilled all the 3/4" DIA dog holes and have used it for over 25 years, and I am SOOOO glad I used HPL as the face.

The plywood top and bottom skins will be plenty sufficient for dog strength. If going for purity and want solid wood top, its pretty risky gluing wood to the non-moving door skin. I would never use SYP - not traditional wood for benches due to the softness of the spring wood between the rings, but thats splitting hairs. SYP will work fine if you really want it, but I would epoxy it entirely for solvent proofing it, and keeping moisture out which would cause the movement forewarned about. Its pretty risky recommending solid over plywood (your door core), but most benches are pretty narrow, and if end and edge banding with solid beech, maybe it will work as long as you groove the end wood and tongue the wood strips of your SYP or beech, and as long as the wood has been ripped to narrow strips, preferably in radial grain (quartersawn, less movement), not tangential grain (more movement).

[Doug Hepler]

Dennis,

As John pointed out above, a flush door is basically a torsion box. My workbench top is made from a castoff exterior door sandwiched between 3/4" birch plywood from the big box store. I glued the laminations with Titebond II applied with a paint roller and clamped with 2 x 4 cauls overnight. The legs are KD fir 4 x 4 and the frame is fir 2x4. There is a shelf underneath. I planned for (boxed in) a large face vise in the front and a medium face vice at the end in lieu of a proper end vise. This bench is rock solid and the top is dead flat. I faced the front edge of the top with oak.

Others would disagree, but I varnished the top with a few coats of acrylic and then waxed it. It sheds glue drips, varnish etc pretty well and I occasionally use a paint scraper lightly to keep it smooth and flat because I use it as an assembly table. Its a bit slippery for some operations but this has not been an issue. If it were I would use a "router" mat.

Doug

[Dennis McCullen]

Thanks to all for the ideas! I hope to start a bench with cooler weather. Until then, I'm sure I'll read a couple hundred ways to be successful. Best to all, DM