Replies

1. 
   Jamie_Buxton | Sep 08, 2004 04:14am | #1

   I've given up on dovetails in plywood because of the tearout problem, but back when I was still trying, I found that some BB sheets would tear and others would not.  When I found a sheet which didn't tear out, I'd examine it very carefully, trying to find some clue I could use the next time I bought plywood -- but I never could figure it out.   I got to the point where I'd try a test run on a sheet.  If it didn't tear I'd make drawers with it.  If it tore, I'd find some other use for it.

   If you're using plywood for drawer sides, you might consider using a tongue & rabbet joint instead of dovetails.  The plywood assures that there is facegrain-to-facegrain glue surface.  There's no opportunity for tearout, and T&R is way faster to make than dovetails.

2. 
   BArnold | Sep 09, 2004 01:04am | #2

   I use a lock rabbet joint for plywood drawers.  It's simple to set up using either a dado blade on your table saw set to 1/4" width or a router mounted in a table using a 1/4" bit.  I prefer to use my router table; it takes only two setups to do all the cuts in the sides and front and back.  One setup with the bit spaced 1/4" from the fence; one with the back of the bit flush with the fence.

   Sides are identical as are the front and back.  If using 1/2" bottoms as I do for shop drawers, the same setup allows me to cut the 1/4" rabbet around the edge of the bottom panel which, coupled with the 1/4" groove for the bottom panel cut in each of the other four pieces makes the bottom panel flush with the bottom of the four sides.

   Bill Arnold
   Custom Woodcrafting

   Food for Thought: The Ark was built by amateurs; the Titanic by professionals.

1. 
   Fingrs | Sep 09, 2004 03:32am | #3

   Thanks, Bill (and others who responded).  I agree that dovetails are probably not the best way to go for plywood drawers.  Modern adhesives and effortless drawer slides virtually eliminate the need for the strength offered by a dovetail joint.  Besides, in plywood such joints are not nearly so strong as in solid wood.

   But the client wants dovetails.  Using material such as baltic birch with all its laminations gives a pretty nice look to the joint. 

   Since what I've goten so far is suggestions to use a different type of joint (and I'm not complaining at all...they're good suggestions), I think I'll probably do some experiments with sealing the ends of the plywood using polyurethane, sanding sealer and any logical leftovers that are in the finish cabinet. 

   I'll post the results, even if they're bad...

   Lofton

1. 
   nikkiwood | Sep 09, 2004 04:20am | #4

   If your client really, really, really wants dovetails, how about using solid lumber instead of the BB?

   If you are using side mounted drawer glides (and a solid lumber front), how about using a sliding dovetail?

   Do you cover up the exposed edge with BB?

2. 
   lwj2 | Sep 09, 2004 01:35pm | #5

   Lofton, you might consider sealing the ends with polyurethane glue -- Gorilla, other similar brands, or a clear epoxy glue.

   Good luck.Leon Jester

   Roanoke VA

1. 
   Fingrs | Sep 09, 2004 03:09pm | #6

   Good suggestion, Leon.  Gorilla is a bit messy and too dark in color.  What sort of clear epoxy would you suggest?  I'm not familiar with epoxy's other than the Minwax/Bondo stuff. 

1. 
   lwj2 | Sep 10, 2004 06:16am | #8

   I've used a 5-minute epoxy --- Duco, I think --- that dries pretty clearly.

   IIRC I bought it at either Lowes or (gods forgive me) Walmart.

   The stuff I purchased came as a double syringe, so you squeeze out equal parts of A & B simultaneously.

   Good luck.Leon Jester

   Roanoke VA

2. 
   Fingrs | Sep 10, 2004 06:21am | #9

   Gotcha.  And Thanks!  I've used that stuff before and will include it in my "experiment".  Watch this space...

3. 
   Norse | Sep 12, 2004 03:36pm | #10

   What sort of clear epoxy would you suggest?

   West Systems is my favorite epoxy and easy to use. But like the others, I've given up on dovetailing plywood and gone to rabbied joints. The one suggestion of using spril bits sounds good but way too many set ups. I've watched "Norm" blow out plywood dovetails too.

   Norse

4. 
   Fingrs | Sep 12, 2004 05:18pm | #11

   Thanks, Norse.  Looks like this may be my last batch dovetailed plywood drawers.  Of course, one approach is to fill the tearout once the drawers are assembled.  Since the tearout is on the sides, a filler that's close in color to the plywood's veneer will fill voids and leave the "endgrain" visible.  This is what I've done in the past and it looks fine; however, it's time to move on to other joinery for this application.

3. 
   Andrew | Sep 09, 2004 07:29pm | #7

   Try using a spiral router bit to rout out most of the waste between the tails, and then use the dovetail bit. I use spiral bits with my leigh jig and they have dramatically reduced tearout. I use a 5/16" solid carbide end mill designed for metal working. hope this helps

   andrew

4. 
   CRAIGCONEY_M | Sep 13, 2004 08:36am | #12

   I've gone to dowelling my plywood drawer boxes.   Can you purchase the boxes from a drawer mfg?

1. 
   Fingrs | Sep 13, 2004 03:50pm | #13

   Thanks, Craig.  Doweling is an interesting option.  I prefer to make the boxes myself, and don't know of a source to buy them.  I can make up a mess of dawers in a day or two while ordering them would take longer, I suspect. 

1. 
   CRAIGCONEY_M | Sep 13, 2004 08:33pm | #14

   Western Dovetail, Decorative Specialties, many others.  At some point the frustration level and $$ amount will point to letting somebody else do it while you concentrate on something else than the plywood dovetail drawers. 

   Would you be able to do the thru dovetails on a TS rather than your router setup? 

   I build my plywood boxes out of prefinished BB and changed over to 5mm dowels about 6 months ago.  Before that I used a lock miter bit or dovetails.    The dowels are alot faster.

5. 
   mudman | Sep 13, 2004 08:45pm | #15

   I don't have a lot of experience with dove tail jigs, so I don't know if this is feasible or not. If you deeply score the cut lines it should prevent it completly. Perhaps you could make one drawer side and use it as a template to score the "keeper".

   Mike

   please excuse my spelling.