Plywood joinery

[Bill Holt]

Hand cut DT in BB.  Actually doing two drawers today.  I'm pretty slow at it, but it is very satisfying.

[Aram]

Thanks. I have a question about these. I have a similar bit from Freud, a drawer lock bit but without the mitered corner. Even with poplar, I have to take several passes with it to get a clean cut. I've tried it with plywood, and even if I devise a way to creep up in several small cuts, and follow the drawer piece with a backer board, I have often had a blowout problem. Kind of surprised me.

Is that an issue with this bit? How do you tame it? Lots of little cuts, or...?

Thanks.

[CARYinWA]

For the kitchen I wood use solid wood with dovetails.  For plywood I use the lock rabbit.  Pocket hole,  Biscuits, and Dominoes I have seen  mentioned yet.

[Steve N]

Thanks. I have a question about these. I have a similar bit from Freud, a drawer lock bit but without the mitered corner. Even with poplar, I have to take several passes with it to get a clean cut. I've tried it with plywood, and even if I devise a way to creep up in several small cuts, and follow the drawer piece with a backer board, I have often had a blowout problem. Kind of surprised me.

Is that an issue with this bit? How do you tame it? Lots of little cuts, or...?

Thanks.

I can't speak for everyone, but what I have found important is below.

Yes they are removing a chunk, and if you try to "sneak up on the proper cut" by moving the fence you will get sloppy cuts, and poor fits. So due to the fact you are removing a bit of stock with each pass you need to do 2 things for successful cuts. I always use a set up block, not saying it can't be done by measurement, but it is silly easy with a good set up block. It might not be obvious to everyone, but this is a right side of the router table, to the left side of the router table cut, and only that direction. After getting your height, and depth properly set you need to.

1) let the bit do the cutting, never push one of these, or for that matter any router bit faster than the bit can cleanly cut, or you will get a rag tag cut. Could be a safety concern as well, depending on how hard you are pushing.

2) always back the stock you are cutting with a backer block directly behind the stock you want cut. The blowout only occurs as the bit leaves the stock at the end of the cut. If you stop before it leaves like with a backer board, or "bury the end of the cut" there is no "leave" to blow out.

I feel this is not just important for a good cut, but is a small safety factor. If you allow the cut to blow out, you can also lunge forward a bit as it does so, and depending on your stance/position, it can put your hand/arm right into the cutter. The cut with your piece vertical is hard to do and use a push block, but backing up the cut with a piece on edge acts like a push block, and backer board all in one. Plus if you do many, and some are deep drawers, or the assembled piece has long sides, you may see the benefit of having a tall router table fence, so you don't want to try to shove the piece over the fence. Standing an 18" tall piece up against a 2 1/2" tall fence can get awkward
Use of these can also help on the uprights.

[rwe2156]

I do not like machined joinery in plywood too much brittleness and tear out you have described.

For DT's I only use solid wood. I use a hybrid method in which I cut the tails on the TS with a rip blade ground to 7 degrees then chop the pins by hand.

For plywood, I think a simple rabbet with 1/8' dowels will look better than screws.
And please, edge band them!!

[WaterlooMarc]

I guess I'm in the minority but I do mine with dominos. Super quick and self squaring. Never tried a lock rabbet though. Might need to look into that.