# 1/4" plywood glued into to 3/4"?



## HokieMojo (Mar 11, 2008)

I've got a question that I hope someone can help me with. I bought a couple sheets of 1/4" cherry plywood a coupld years ago before I knew anything about woodworking. Now that I've learned more, I've discovered that some of the projects I planned to use it for would be betterserved with 3/4" plywood.

My questions are:
Will I regret trying to attach 1/2 plywood to 1/4 inch to get to 3/4 inch (I know that plywood isn't full thickness)
Could I do this without a vaccuum press to clamp the two sheets together

I can't get 3/4 cherry near me without paying a ton in shipping so thats not much of an option. My alternative is to change the design pretty substantially, and I'd really rather not do that. Any advice would be appreciated.
Thanks!


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## DannyBoy (Oct 26, 2007)

I'm not the expert, but I would think that you can do this. Isn't this basically veneering?

If I were to do it, I would just make sure every foot or so had some pressure to it. On thinner pieces you can use clamps, but wider ones you can use bricks. I have some cinder blocks hanging around the shop for the same basic use.


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## rickf16 (Aug 5, 2008)

What are you plan on making with the plywood? You could use the 1/4 thickness if you build a frame using 3/4 thick stock.


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## 8iowa (Feb 7, 2008)

I think this would work. However, in my area it is impossible to find decent, flat 1/2" plywood.


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## sIKE (Feb 14, 2008)

I have done this several times. I had one project that I was working on and came across a nice 1/4 sheet of Red Oak Ply in the broken bin at the Borg, I just glued it to a piece of 1/2 ply used spring clamps on the edge put some support under the 1/2" ply and placed bricks at even intervals to insure there was enough weight pressing down on the Red Oak ply that it was even. Then cut it to size and it looked beautiful.

This project was the bin organizer from Wood magazine. I made it as a gift for someones new shop. He preceded to paint it all gray. I still cringe when I think about it.


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## Julian (Sep 30, 2008)

I just did this for the top and back of the mahogany dresser with secret compartment that I built a few months back. I used 1/4" mahogany ply backed with 1/2" baltic birch ply. If you want it flat, i would suggest using baltic birch ply also. I just made cauls out of 2x construction lumber and made sure to taper the last 10" or so of the ends 1/8" to make sure that the middle would get plenty of pressure while clamping.


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## cabinetmaster (Aug 28, 2008)

I agree with julian. Use 1/2" baltic birch for the best flatness. We use 1/4" plywood everyday for the finished ends of cabinets. We spray laminate glue on the 1/4" plywood and the 3/4" plywood, let them set for about 2 to 5 minutes and bond together. We then use a non-marring mallet and tap the pieces all over to get a tite bond. Be careful and get the pieces where you want them cause once they touch they are bonded, just like laying laminate on a sub-strate.


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## kiwi1969 (Dec 22, 2008)

i,ve done with no problems.


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## anotherbrick (May 22, 2008)

first,putty the uneven area to form a even surface
second,sand the surface you're going to apply glue,then the glue will be easier to bond
third,use clamps and bricks to give it enough pressure,the more pressure the better,try to make sure the pressure on every area are the same.


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## ajosephg (Aug 25, 2008)

I've been told by several cabinet shops that the grain pattern matching, etc. on 1/4 inch plywood is better than that on 3/4 inch, so if that is true that is another reason to use it.


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## roman (Sep 28, 2007)

I laminate different thicknesses of plywood substrates all the time,

If you dont have contact cement then plain old white, yellow glue will work and if there is concern over proper glue coverage then use a paint roller to apply the glue. You can use paint cans, bricks, concrete block etc to apply pressure and by cutting the sheets into smaller parts (dont forget to cut them bigger then what you actually need) and glue them this way as its easier to handle

Good Luck


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## CraigFeuerzeig (Mar 4, 2009)

Curved cauls will make easy work of this.


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## SeanBenetin (Mar 10, 2009)

As long as the piece will be utilized in a way to keep it straight it will work fine. If this is "free floating" or not held rigidly in place it will bow. Laminations need to be made in odd layers 3,5,7, etc. which in turn equals even numbers of glue joints. This is what keeps panels flat (relatively) This is why all sheet goods come in odd numbered layers. When you glue together two sheets it equals and even number of layers and an odd number of glue joints. If you need the piece to remain flat on its own you will need a backer on the opposite side to balance the panel.


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## TraumaJacques (Oct 25, 2008)

Were you thinking of doing 4×8 sheets at a time or individual pieces? 4×8 without a vacume press would be a clamping nightmare.


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