Dovetailing 1/2" plywood?

[bobT]

Status: Entered
Assigned To:: Unassigned
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Using the Porter Cable Dovetail Jig, need a solution to avoid the destructive plywood splintering I am getting. I am using good grade plywood (specifically 1/2"). . . do you think applying titebond glue to ends will avoid the tearing and splintering??

Bob

 

[lwhughes149]

Re: [How Do I-Help Desk] Dovetailing 1/2" plywood

Bob, I started making dovetails in good quality 1/2" birch plywood for the chest of drawers I just finished. I had a new bit for my new PC dovetail jig. After making just one drawer I found that I had burnt up the bit, it appears the glue in the plywood dulled my bit. Good luck to you if it works, but I don't expect I will use dovetails on plywood in the future. Just my 2cents worth. Lorraine

 

[McRabbet]

Re: [How Do I-Help Desk] Dovetailing 1/2" plywood

When making drawers, I routinely cut the dovetails for the sides on my router table all at once. I use a precision fence (I have a Jointech Cabinetmakers fence) and cut a stack of sides for multiple drawers all at once. I've done as many as a dozen 1/2" Baltic Birch sides stacked and clamped between a sacrificial piece on each side and pushed through the bit at the correct offset from the fence. By stacking several sides and using the sacrificial pieces in front and behind the stack, I save lots of time and have zero tearout. I then adjust the fence to the next cut (on a template in the fence) and repeat.

In your case, I recommend using a sacrificial piece of stock in front and behind the drawer side. I assume you are using Baltic Birch, too.

 

[Gofor]

If you are hand-cutting, use a sharp saw, sharp chisel, and backer boards. Emphasis on the Sharp. Work the chisel cuts from both sides.

Go

 

[Alan in Little Washington]

I used 1/2" ply for all my shop drawer boxes. It wasn't Birch, but one of the Asian plys so just as hard or harder than Birch. The key to using ply for dovetailed drawer boxes is (1) start with a climbing cut across the outside face before starting to cut the dovetails, (2) use a backer board to prevent tearout on the back, (3) use a sharp router bit, and (4) take it slow and don't feed the router too hard. Even then you are likely to get some tearout.

You can just barely see the dovetails in the drawer side in this pic.

 

[Travis Porter]

I second Alan's comments on all counts. It is doable, but you are most likely still going to have chip out.

 

[Nativespec]

I do not use plywood for dovetail drawers since no matter how good the "qualifty" of the product, there will be voids and gluing defects and even with properly placed sacrificial backing boards and the finest bits money can by and perfect wind conditions in the shop (just kidding) I would still have tearout. I started using poplar for the sides and backs of drawers and I do not concern myself with how to get a 5' wide piece of plywood into the back of my truck.

Thanks,

David

 

[bobT]

Thanks to all . . . I think I will try the backer board idea. I have cut all the material for 4 GI jo boxes for my grandson for christmas . . . maybe I'll just make 45deg joints and forget trying to be fancy. Thank you all for the support.
Bob

 

[Jim Murphy]

Hey Bob,

I don't like plywood for drawers,but when I have to I use a half-blind mortise joint (also called a locked rabbet joint).
[FONT=Arial,Helvetica,Geneva,Swiss,SunSans-Regular][/FONT]
[FONT=Arial,Helvetica,Geneva,Swiss,SunSans-Regular]Locked Rabbet Drawer Joint[/FONT]

[FONT=Arial,Helvetica,Geneva,Swiss,SunSans-Regular]Locked rabbet drawer joints fasten the front of a drawer securely to the sides. They may be made on a table saw with a dado blade or with a router mounted in a table with the bit shown below. [/FONT]
​

For 1/2" stock, instead of a dado you can easily multi-pass the material through the standard kerf blade. When you cut the front, use scrap pieces to set the fence so one pass + a reverse pass centers with the correct width of cut (ideally, 1/3 of thickness). I just made a large plywood drawer Saturday with this technique and it's pretty simple.