# laminating two sheets of plywood for a desk top



## kjhart0133 (Feb 4, 2009)

I am presently in the middle of making a new desk for my home office. It will be approximately 6' x 3' in overall dimension. There will be two tapered legs on the left and on the right will be a three drawer pedestal. I have the legs, the apron and the pedestal almost finished and am now thinking about the top. 

I would like a sturdy, thick top and am considering laminating two pieces of plywood together: a 3/4" sheet with oak or walnut ply on the top, and beneath that a 1/2" sheet to bring up the top's thickness to about 1-1/4". I'd square off the top and put a nice hardwood edging around it. I don't have access to a planer or jointer so nice plywood is my only solution for a suitable top.

My question concerns laminating the two sheets. 

1. Should I glue them or screw them together? Will I have a problem with different expansion/contraction rates on the two pieces -- I guess there's no guarantee they'd have identical expansion properties, though they should be similar. 

2. How's the best way to glue and clamp two 6x3 sheets together? Are there clamps that can reach the center of the tabletop?

3. Is this just a bad idea? Do you have a better one? I suppose I could live with just a 3/4" thick top, but it seems kind of skimpy.

Any thoughts or help would be greatly appreciated.

Thanks,

Kevin H.


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## Julian the woodnut (Nov 5, 2008)

I would just use titebond 2 and use the small 3-4" wide disposable rollers to roll it on uniformly. Clamps are not the way to go, a vacuum bag is. I'll assume you don't have a vacuum setup, so just screw the two sheets together. There is no problem with expansion and contraction with plywood, so it won't be a problem.


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## Roger Newby (May 26, 2009)

How about a 1 1/4" or wider walnut strip all around the 3/4 top. Gives the illusion of extra thickness without the hassle.:thumbsup:

Roger


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## cabinetman (Jul 5, 2007)

If you have to have it that thick, just glue and screw from the bottom. As it was said there is no expansion/contraction problem. 

You don't really need to glue two pieces. Use just the 3/4" and glue and clamp a 3/4" x 1 1/2" edge all the way around. It will stiffen it up and give it a thicker look.


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## woodnthings (Jan 24, 2009)

*Consider this:*

I've made lots of workbench and desk tops from solid core doors. I use birch, but I know oak is also available. They come in 36" widths as standard and you'd just need to cut down to 72" for your length. I believe that thickness is standard at 1 3/8 " and 1 3/4 ". 
If you are using only one 3/4 ply you will need to glue on local attachment blocks for your legs to provide sufficient screw depth.
If you are glueing up 2 pieces you must start with a flat surface to glue on. That might be a problem.:blink: Heavy weights in the center such cement blocks will work instead or in addition to screws from the backside. You probably will trim the edges in a matching wood to hide the end grain and plys. Keeping these pieces properly aligned during glue up is important since any sanding or planing afterward should be minimal to flush out the surface. Crossing the ends where the grain runs the length will require careful sanding as well. Do not use the cheap thin veneer plywood, HD etc, since it will sand through quickly. It's not forgiving in that regard. Good luck, :thumbsup: bill


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## kjhart0133 (Feb 4, 2009)

Thanks all for the helpful replies. I will consider using only a 3/4" sheet and trimming the edges with 1-1/4" hardwood to strengthen it and make it look thicker. 

Kevin H.


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## wsommariva (Jan 3, 2010)

I have the same situation. Making a workbench. I'll look for a solid core door, but if I use two 3/4 inch pieces of plywood, 30" x 80", I'll use yellow wood glue and screw from the bottom. Wood screws, 1.25" Question is how many screws and where do I place them?

Second question: what do I use for the edge to cover/protect the exposed plys?

Thanks


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## woodnthings (Jan 24, 2009)

*If you use plywood*

Make 3 hash marks on an angle on one end when you purchase it. This will help determine how to reverse and flip it when you glue it together. You want to counter act any warping forces by having them in opposition when you glue it. Yellow glue rolled on, 1 1/4" screws on an 8" grid. The screws are just to hold it together lacking a suitable flat surface and weights which you could also use. They can be removed after the glue sets up. The glue is the strength. Let the plywood acclimate to the room temperature and humidty for a day and keep them separated. A good quality hardwood plywood will not be so temperamental, but construction grade will be. You can glue on almost any hardwood for a perimeter banding, 1/4" to 1/2" thick. 
That's my advice for Ya. :thumbsup: bill


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## wsommariva (Jan 3, 2010)

Didn't think glue was so strong. Thank you for this advise. I learned a few good things that I will use for a lifetime.


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## wsommariva (Jan 3, 2010)

Well, I ended up buying a solid core door at Home Depot for $54. Has a hardwood veneere although I don't know what kind it is. Worked great. I think cheaper than two pieces of 3/4 plywood, so I'm very happy with the final result. 

Would anyone put a finish on it? I'm thinking no since right now the legs match the top colorwise.


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## woodnthings (Jan 24, 2009)

*A work bench surface*

Could be a piece of 1/4" to 1/2" hard board or plywood that you can reverse when it gets worn, painted or drilled into, etc or you just want a fresh look. Mine is 1/2" from HD. 2 sided sticky Carpet tape holds it in place or a 1x frame around the perimiter will hold it in place on the door. Just a thought. :thumbsup: bill


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## wsommariva (Jan 3, 2010)

Ok, I'm going to leave it as is. After years of use I can always add a piece of hardwood as you suggested.

What does "1/2 inch from HD" mean?


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## wsommariva (Jan 3, 2010)

Home Depot.


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## TheMachineWarehouse (Jan 12, 2010)

There are always different ways of doing it. I have had good luck by hand of using contact cement to bond the (2) pieces together and then you can use a 1-1/4" piece to finish up the edges like everyone else suggested. If you also seal the table with a stain or clear coat, it can help avoid warping. You won't have a problem with shrinking with plywood due to it's design, but you can have some serious warping problems when moisture is added.


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