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+--- Thread: [HELP] Switching To A QCTP (/thread-3781.html)
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RE: Switching To A QCTP - randyc - 12-13-2017
FWIW, as stupid as this sounds, several experiments indicated that .001 DOC was too much for my HSS tool !!!! It wore significantly - maybe .0002 over two inches on a CRS workpiece. That's not good and I might understand chatter if the local cutting edge has broken down significantly (BTW, the scuffed edge is visible under magnification). But with a sharp carbide cutter like you used, it doesn't make sense.
Somewhere in the neighborhood of 30 degrees is also what I used (but didn't measure it). From what I read a few years ago, the angle isn't critical and anything between 15 and 45 doesn't produce much difference. I guess intuition would suggest that the further the angle is from vertical, the less wear (more cutting surface ?) but also less of a "knife-edge" if that is important.
It's a fascinating concept but obviously has weaknesses and so far not a single thing that I've read convinces me that the writer has a good handle on the process. There was one person who REALLY tested the concept, even extrapolating it to fly cutters. I can't recall his name but probably a quick search will turn it up. I may do that later today.
This is the geometry of my shear tool - unused since I made my initial tests. It's really sharp (and maybe TOO sharp ?), you can see the polished areas on the edge from the Arkansas stone.
[attachment=15397][attachment=15398][attachment=15399]
BTW, I never quite "got" the tangential cutter. The geometry is easily replicated with a conventional AR style cutter so what would be the advantage ???
RE: Switching To A QCTP - randyc - 12-13-2017
Apologies to the OP for de-railing his thread !!!! I'll stay on topic now !