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Peter Grey
 
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"DoN. Nichols" wrote in message
...
In article t,
Peter Grey wrote:

"Grant Erwin" wrote in message
...
It is possible that the bad grinds could have come from user error and
not manufacturing tolerances. You are being a bit sensitive when you say
that what I wrote was nonsensical. More accurately, it is logical, but
you
assert is is unlikely. OK. It's just another point of view. Have I
looked
closely at the Drill Doctor? No. I have a better drill grinder.

GWE


I've managed to come up with good grinds as well as bad grinds using my
DD.
Not orienting the drill properly will absolutely cause the
trailing-edge-higher-than-the-cutting-edge problem mentioned earlier.
I've
found that when I pay attention to getting the drill positioned properly,
that the DD does a very nice job. It can be a little persnickety, but
ninety five percent of the time I get a good result on the first try.


Except that it does not seem to do a good job with the
split-point drill sharpening with the smaller sizes.

One thing to watch for, however, is that it is sensitive to the
helix angle. The common jobbers' style bits work fine in it, if it is
used as it should be. Those with either lower or higher helix angles
wind up mis-positioning the flutes, and can wind up with excessive or
negative relief as a result. (What is needed is a couple of more index
marks for those differing helix angles, and matching detents.

It should be said that I'm using my DD on standard run-of-the-mill drill
bits, so your observations are undoubtedly correct.

Peter