The Devil's miter (Lock miter)

[Kevin Jenness]

No doubt lock miter setups are fussy. When dialed in they allow for a clean result with clamping in one direction. Most cutters require running one set of parts flat and one set on edge, which can be problematic when running long pieces where the parts want to lift off table due to leverage and the sharp corners can get crushed, plus a conventional powerfeed can be a pain to change from horizontal to vertical. I have a Freeborn lock miter set that allows for running everything flat on the shaper table and running a dado on the tablesaw on half the pieces, which I find easier. https://ballewsaw.com/freeborn-pc-28...miter-set.html

I use miterfolds far more often. All that's required is accurately sawn edges held together with packing tape and folded up. Four-sided columns can be wrapped with stretch-film plastic twine to pull the last joint together. I nearly always do miterfolded finished cabinet return panels. For long grain solid wood or plywood they produce a very strong glue joint without much fuss. They do need flat material and straight edges.

Miters on plywood allow for no more than the slightest easing, that's the nature of the beast.

newel miter.jpg