Re: Can I buy an answer?

On Thu, 6 Mar 2008 11:05:08 -0800 (PST), Charlie Gary
<cgary@xxxxxxxxxxxxxx> wrote:

Here I am trying to quote a job, and I need to blast some holes in 1/2
thick A36 plate. A guy wants to tell me Guhring makes what I want,
but they are not responding to my requests for information. I need a
high performance drill that can blast holes fast without pecking. ANY
recommendations?


Later,

Charlie
=============
As usual, very good replies/suggestions in this thread.

If this is for a high volume production operation, the following
observations may be helpful (but these are from an American
manufacturing plant, long, long ago in a land now far, far away).

Based on my observations [I was the SPC study guy] of a very high
volume operation drilling forged [and some cast] slack adjuster
bodies [big-rig air brake truck part] the drill manufacturer is
not the critical factor, but the point [re] grind is, from a
total consumable tooling cost perspective. The machine was a PLC
controlled rotary index center, with drill bushing fixtures,
flood coolant, and gear drive/gear feed [non operator adjustable]
drill heads.

Because of production considerations [piece work] there was
continual problems with the operators not changing tools on
schedule to the point that we had to install a counter that
locked the machine, and required supervisor key reset to resume
after verification of tool change. The problems caused were not
only excessive tool consumption because of extensive rather than
touch-up re grind required [to the extent that it was frequently
cheaper to scrap the drill rather than take the time to re
grind], but the huge burrs generated required extensive/expensive
hand re-work.

As I recall, the Peugeot drill point was selected as optimal for
this use, but the Bickford and Relcon points were very close and
may be better for your application. For what ever reason, we had
to discharge several operators for attempting to resharpen their
own drills by hand rather than using the supplied Peugeot
re-pointed drills from the grind shop (even though we supplied a
"kit" to each shift with the required number of sharp prills and
a spare or two for the scheduled production). They seemed to
feel the points didn't "look right," and indeed the Relcon looks
worn out.

We used the Guhring parabolic flute drills with great success.
These drills did indeed seem to clear the chips better than other
drills. for one source see
http://www1.mscdirect.com/CGI/GSDRVSM?PACACHE=000000047946021

FWIW - these drills had #2MT shanks. I still have 2 that I use
very seldom because of their odd size [27/64]. We had two drill
pointers in the grind shop, an Optima and a Brierly (continual
arguments between the operators about which one worked "best").
Both seemed to work very well. The newer computer controlled
grinders such as the Darex or Winslow may well be a better value
for the money as well as requiring less skilled/experenced
operators. The Conic, X and R points may also be an improvement.
[All the machines look like a "spicy meatball."]
http://www.darex.com/main/
http://www.darex.com/main/content/view/24/56/
http://www.winsloweng.com/drills/drill_tips_content.htm

Good luck and let the group know how things turn out.


Unka' George [George McDuffee]
-------------------------------------------
He that will not apply new remedies,
must expect new evils:
for Time is the greatest innovator: and
if Time, of course, alter things to the worse,
and wisdom and counsel shall not alter them to the better,
what shall be the end?

Francis Bacon (1561-1626), English philosopher, essayist, statesman.
Essays, "Of Innovations" (1597-1625).
.

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