Expert: Jamie Yocono - 6/15/2006

Question
Hi Jaime. I am building a toy chest for our son.  32”L x 18”W x 20”H.  I’m using 3/4" sandply wood.  What is the best/safest way to join the wood.  Should I use nails or screws on the outside/inside?  L-shaped brackets on the inside/outside?

I'd rather not have a lot of nail holes to cover up but I also don't want it to fall apart or for any child to cut their hands on any brackets on the chest.  Any ideas?

Thanks,
Paul

Answer
Hi Paul,

Your question about joinery with plywood is an important one. While plywood isn't an ideal material for cutting joinery, you can machine it so that you can (at least) increase the gluing surface of it. That will make your corner joints stronger. Still, it's wise to reinforce it a little bit.  I will discuss both methods.

You have a couple of choices, but the first would be to machine a corner joint in the plywood. The simplest and strongest would probably be a combination rabbet/dado joint. I tried to find a picture of it on the web, so that I could send a link to you, but couldn't locate one. But- you might already be familiar with the type of joint I am talking about. It's commonly used in drawer making, especially for the front of the drawer box, as this joint locks the box together quite well. For 3/4" plywood, a single 3/8" straight bit will allow you to machine the two cuts in each corner. One cut will be a dado, and one will be a rabbet, and if you do it well, it's quite strong, with adequate gluing surfaces. You could also cut this joint on a tablesaw, if you don't have a router.

Another method for corner joinery would be to use a wooden block inside the corner. This corner block will then allow you to screw from both pieces of plywood (from the outside) into the block, and it's a secure method to use. I would run the block the whole depth of your toy box; that way, no matter where you add a screw, it will have wood to catch it. And I definitely recommend gluing the block in place, too, as this will give you some added rigidity. Remember though- if this toy chest were made of solid wood, you wouldn't glue the block in place, due to seasonal wood movement.

Last- you mentioned metal braces. I'm not a big fan of those, as I think they look bad inside of a piece. But if you feel more comfortable with them, those would work as a last resort. If you're handy with a chisel, you could inlay the corner braces into the plywood, and then putty and paint over them. That way they wouldn't show, which is my preference.

Good luck, I hope this helps. Feel free to write back with any other questions you might have after reading this. And - please take a moment and rate the answer that I have provided. It's good to get some feedback.

Jamie Yocono
Wood It Is! Custom Cabinetry
www.wooditis.com
Las Vegas, NV