I'm going to have to take a minute to digest that ... OK , if I'm understanding this correctly I'll only have to cut one angle on the bottom , the other two will be produced by the way the hole for the collet is bored in the block - 2° tilt to the rear , 5° to the right . If I put a couple of degree angle on the left end I can set the fixture up to do the gash with the end mill horizontal/angled slightly down . Snag
------------- I don't understand the last sentence.
Facing the base bevel, the collet tilts 5 degrees toward you and 2 degrees to the left. Conversely the way I have it in the mill with the collet vertical, the base tilts up toward me and on the left side, which is why the
1/4" parallel jammed under it is at an angle. The easy way to copy that angle is to duplicate the distances from the bar to the back of the base block on both sides, assuming you make the block the same width as mine,
2.5053".
The 5 degree tilt provides back relief to the cutting edge, the 2 degree dishes the edges inward slightly so only the tips cut, even as they dull. I don't think either angle is critical, recommendations I've seen for back relief are a range that almost always includes 5 degrees. Likewise grinding while on the 25 degree base bevel merely removes the bulk of flute material behind the cutting edge, or balances it if you ground most away faster on a bench grinder. Surface grinder wheels can explode if you try to force too heavy a cut, I've been nearby on another machine when a kid did that.
I think you can make all cuts with the end mill or boring head vertical, and do most of the machining on the base with it square or single-angled in the vise. On my mill the head can be tilted and swiveled to bore the angled collet recess directly, with the base in the milling vise, though squaring (tramming) it up again afterwards is a lot of trouble since the round ram shifts when the clamps are tightened.
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