Gunner Asch wrote:

No idea. Ive bits and pieces of old sets and when I removed it from the
collet holder, it came out in two pieces. It was at least 20 yrs old
and came from a shop that did a lot of interupted cuts. Shrug

Wow. Never saw a collet insert break. I *have* seen the collet body crack many a time due
to overtightening.

First clue is a very long relative to diameter parabolic drill is putting holes in random
locations. Spindle running about 6K rpm so a that crack causes the drill to lean away
from the Z axis and start to whip due to centrifugal forces. Where the drill tip contacts
the part each cycle is random.

Wes
--
"Additionally as a security officer, I carry a gun to protect
government officials but my life isn't worth protecting at home
in their eyes." Dick Anthony Heller

On Mon, 26 Apr 2010 16:31:00 -0400, Wes
wrote:

Gunner Asch wrote:

No idea. Ive bits and pieces of old sets and when I removed it from the
collet holder, it came out in two pieces. It was at least 20 yrs old
and came from a shop that did a lot of interupted cuts. Shrug

Wow. Never saw a collet insert break. I *have* seen the collet body crack many a time due
to overtightening.

First clue is a very long relative to diameter parabolic drill is putting holes in random
locations. Spindle running about 6K rpm so a that crack causes the drill to lean away
from the Z axis and start to whip due to centrifugal forces. Where the drill tip contacts
the part each cycle is random.

Wes

Ive seen a number of them break, but generally the smaller ones, suitble
for 5/8 tool holder service in CNC 5C machines, such as the OmniTurns.

**** happens. While Im surprised, it doesnt bother me much. **** breaks
on occasion. If not..Id not be in business (such as it is at the
moment).

The collets Ive got, as I indicated above...were a mixed bag of
leftovers and unwanted Stuff that came from various machine shops over
the years. It may well have been metric and over tightened to hold a
1/2" endmill. Shrug..no markings on it. But it was CLOSE to a .50

Like 5C collets, R8, etc etc..it all has a life span. Some die
early..some die very late, some live to be very very old.

I tossed about 8 cracked 5C collets last year, that were all Hardinge.
Some had a busted finger, some had cracked fingers, one had cracked
across the face.

Stuff I picked up here and there over the years.

Shrug

Gunner


"First Law of Leftist Debate
The more you present a leftist with factual evidence
that is counter to his preconceived world view and the
more difficult it becomes for him to refute it without
losing face the chance of him calling you a racist, bigot,
homophobe approaches infinity.

This is despite the thread you are in having not mentioned
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