Hi Dietrich, I definitely used a backer board whenever I could. The cuts made from the outside surface that end on the inside precluded the use of a backer. Slow forward motion and a nice sharp up cut spiral made a very clean cut; even in the shedua which is quite fibrous.
I just did a couple more boxes this same way and believe I took some more pics of the process. I will be home tomorrow and will check and post what I find. In the mean time I can tell you my hinges were just over 3/4" wide and 1/8" high when closed. I cut the mortise just shy of 1/16" in depth so that there would be a slight gap when the lid was closed to make room for the little felt bumpers I like to use.
The bit is a 3/8" solid carbide (Whiteside) upcut spiral so I make two passes side by side. The mortise must be a little over 3/4" so there is a small rib left between the cuts that I take out with a butt chisel.
The mortises are actually more like slots and this makes them easier to cut but more prone to boo-boo's at the exit point. Using backer boards and a nice sharp cutter turning very fast gives me the best result. I'll try to post some better pics ASAP.
Last edited by glenn bradley; 09-05-2009 at 04:08 AM.
Any sufficiently advanced technology is indistinguishable from magic.
- Arthur C. Clarke