Joinery and Assembly for Cabinet Miters

Using tape and glue to hold and secure long miter joints. December 2, 2011

I am looking for ideas on how to join the miters below. I have a lot of them to do so I am looking for an accurate and efficient way to do them. Does anyone know of/have experience joining two 22.5 pieces together? Is there a locking bit that can be used for 45?

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Forum Responses
(Cabinetmaking Forum)
From contributor M:
There are a couple of options - spline or biscuit the miters, bird's-mouth bit, 8-sided version, or two-piece 22.5 degree lock miter bit set.

From contributor T:
Packing tape, spring clamps, Hoffman keys. If possible packing tape is preferable.

From contributor L:
Ditto on the packing tape (2" plastic, the heavier 3M stuff), itís the only way that works for me when joining mitered veneered sheet goods. Align the pieces face up, tape the length of the joint, flip and glue. The tape holds the face of the joint tight/aligned and glue free. You can use strips of the same tape to hold the joints closed whole they cure. Adding some blocking across the joints would be a good idea. I didn't for the example and it still worries me. As you can see it also works for mixed materials/thicknesses.

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From contributor T:
The glue works fine. We did 400 display tables for a national retailer (a while back) all compound miters some as big as 5'x10'x1.5', we shipped them in cardboard boxes to every state, just glue, and we had zero failures.

From contributor C:
Packing tape - as said, the 2" thick and stretchy kind. Be sure to use a feather board or similar over the blade as you rip otherwise you could end up with slightly curved miters and that will double when you put them together.

From contributor U:
If I have more than a handful of pieces I use my jet weld gun. I still put the tape across and along the miter but instead of yellow glue, taping, and then removing the tape when the glue dries (be careful you don't pull the grain when removing the tape, have had to use a heat gun on sensitive materials in the past) I just put a bead of yellow glue and then a bead of hot glue to act as the clamp.

From the original questioner:
Thanks for all the input! I am using the 22.5 degree lock miter bit from MLCS. It seems to be working great.