Awl--

90 deg 3-flute c-sink, .225" deep into 6061 alum that is already
substantially c-drilled, #5, about .250 deep.

Problem: chatter marks, altho not audible, and not really bad looking--not
a bad effect, really.
Just would like a really smooth finish on occasion, which I achieved once,
but have not been able to replicate.

I have found a slow rpm much "friendlier" than faster rpms, ie, less than
300, vs. over 750.
True?
Push w/ more force? Less? some combo w/ different rpm? "Finish cut"?
Diff. style c-sink? Oils?

TIA.
--
Mr. P.V.'d
formerly Droll Troll

"Proctologically Violated©®" wrote:

Awl--

90 deg 3-flute c-sink, .225" deep into 6061 alum that is already
substantially c-drilled, #5, about .250 deep.

Problem: chatter marks, altho not audible, and not really bad looking--not
a bad effect, really.
Just would like a really smooth finish on occasion, which I achieved once,
but have not been able to replicate.

I have found a slow rpm much "friendlier" than faster rpms, ie, less than
300, vs. over 750.
True?
Push w/ more force? Less? some combo w/ different rpm? "Finish cut"?
Diff. style c-sink? Oils?

TIA.
--
Mr. P.V.'d
formerly Droll Troll

Slooower is better, these are even better:
http://www.rjmeng.com.au/weldon.htm

Tom

Proctologically Violated©® wrote:
Awl--

90 deg 3-flute c-sink, .225" deep into 6061 alum that is already
substantially c-drilled, #5, about .250 deep.

Problem: chatter marks, altho not audible, and not really bad looking--not
a bad effect, really.
Just would like a really smooth finish on occasion, which I achieved once,
but have not been able to replicate.

I have found a slow rpm much "friendlier" than faster rpms, ie, less than
300, vs. over 750.
True?
Push w/ more force? Less? some combo w/ different rpm? "Finish cut"?
Diff. style c-sink? Oils?

TIA.
--
Mr. P.V.'d
formerly Droll Troll


Like Dev says go slow. Don't tease the feed. Some times when chatter
starts its self perpetuating so try not to ever let it get started. The
chatterless style are the ones that chatter the most. I prefer the style
with the 1 hole going thru at an angle. They might be called true cut
types. Snug your spindle lock to take up any spindle clearance but still
allow spindle feed.

In article ,
says...
Awl--

90 deg 3-flute c-sink, .225" deep into 6061 alum that is already
substantially c-drilled, #5, about .250 deep.

Problem: chatter marks, altho not audible, and not really bad looking--not
a bad effect, really.
Just would like a really smooth finish on occasion, which I achieved once,
but have not been able to replicate.

I have found a slow rpm much "friendlier" than faster rpms, ie, less than
300, vs. over 750.
True?
Push w/ more force? Less? some combo w/ different rpm? "Finish cut"?
Diff. style c-sink? Oils?

Single flute c'sink, relatively slow speed, heavy feed, set a stop to
control depth.

Single flute c'sink
http://www.maford.com/taf/catalog.taf?category=a11

Ned Simmons

"Proctologically Violated©®" wrote in
:



I have found a slow rpm much "friendlier" than faster rpms, ie, less
than 300, vs. over 750.
True?
Push w/ more force? Less? some combo w/ different rpm? "Finish
cut"? Diff. style c-sink? Oils?

Drop the RPM down to 100 or so...maybe less...and keep the feed pressure
on.


--
Anthony

You can't 'idiot proof' anything....every time you try, they just make
better idiots.

Remove sp to reply via email

Proctologically Violated©® wrote:
Awl--

90 deg 3-flute c-sink, .225" deep into 6061 alum that is already
substantially c-drilled, #5, about .250 deep.

Problem: chatter marks, altho not audible, and not really bad looking--not
a bad effect, really.
Just would like a really smooth finish on occasion, which I achieved once,
but have not been able to replicate.

I have found a slow rpm much "friendlier" than faster rpms, ie, less than
300, vs. over 750.
True?
Push w/ more force? Less? some combo w/ different rpm? "Finish cut"?
Diff. style c-sink? Oils?

TIA.

If you LIGHTLY dull two of the three flutes only one will cut while the
other two burnish, and this helps eliminate chatter marks. A steady
feed pulling a constant chip is also important. At the end of the feed
it helps to hold the tool on the surface for a few revs. It's really
nice if you have some kind of depth stop to push against, so the tool
doesn't bounce around at the bottom.

Later,

Charlie

"Ned Simmons" wrote in message
...
Single flute c'sink, relatively slow speed, heavy
feed, set a stop to control depth.

IAWTP

On 16 Jan 2006 17:13:07 -0800, "Charlie Gary"
wrote:

If you LIGHTLY dull two of the three flutes only one will cut while the
other two burnish, and this helps eliminate chatter marks.

A smeared finish?
Keep the IPR feed up.
--
Cliff

Proctologically Violated©® wrote:
Awl--

90 deg 3-flute c-sink, .225" deep into 6061 alum that is already
substantially c-drilled, #5, about .250 deep.

Problem: chatter marks, altho not audible, and not really bad looking--not
a bad effect, really.
Just would like a really smooth finish on occasion, which I achieved once,
but have not been able to replicate.

I have found a slow rpm much "friendlier" than faster rpms, ie, less than
300, vs. over 750.
True?
Push w/ more force? Less? some combo w/ different rpm? "Finish cut"?
Diff. style c-sink? Oils?

TIA.
--
Mr. P.V.'d
formerly Droll Troll




PV, I like the Ford single flute countersinks.

--
Regards,
Steve Saling
aka The Garlic Dude ©
Gilroy, CA
The Garlic Capital of The World
http://www.pulsareng.com/

Cliff wrote:
On 16 Jan 2006 17:13:07 -0800, "Charlie Gary"
wrote:

If you LIGHTLY dull two of the three flutes only one will cut while the
other two burnish, and this helps eliminate chatter marks.

A smeared finish?
Keep the IPR feed up.

Yes, feed it hard enough to constantly load the tool. But if you
can't seem to get there, dulling the tool a little sometimes keeps it
from getting into catch and release mode.

Later,

Charlie

pv,

Always us s single flute countersink, even in steel.

MA-Ford makes good ones

Mark



"Proctologically Violated©®" wrote in message
...
Awl--

90 deg 3-flute c-sink, .225" deep into 6061 alum that is already
substantially c-drilled, #5, about .250 deep.

Problem: chatter marks, altho not audible, and not really bad
looking--not
a bad effect, really.
Just would like a really smooth finish on occasion, which I achieved once,
but have not been able to replicate.

I have found a slow rpm much "friendlier" than faster rpms, ie, less than
300, vs. over 750.
True?
Push w/ more force? Less? some combo w/ different rpm? "Finish cut"?
Diff. style c-sink? Oils?

TIA.
--
Mr. P.V.'d
formerly Droll Troll

On Thu, 19 Jan 2006 07:10:56 GMT, "Mark Mossberg"
wrote:

pv,

Always us s single flute countersink, even in steel.

Then why would they make ones with more flutes?
Try a piloted countersink with the proper hole size/pilot ..?
Perhaps an even number of flutes might lead to more
possible chatter ...
--
Cliff