Sometime back one of our esteemed members posted that
if his machine had reverse, that he would only use a
keyed chuck on that machine.

I've been pretty much spoiled by keyless chucks.
I'm trying to decide whether to buy a keyless or
keyed chuck for a lathe. If I'm just drilling a hole,
keyless is just fine. Putting a tap in the keyless
and tapping wouldn't be a problem because you are
still going forward. But when you put the lathe
in reverse to remove the tap, would the tap
loosen in the chuck? I would assume that there
is less resistance pulling the tap out, so maybe
it wouldn't loosen. Also I assume if it did
loosen, the worse that could happen is I'd
have to remove the tap by hand.

So I'm looking to those with the experience
to help me decide.

Thanks,
Wayne

Wayne wrote:
Sometime back one of our esteemed members posted that
if his machine had reverse, that he would only use a
keyed chuck on that machine.

I've been pretty much spoiled by keyless chucks.
I'm trying to decide whether to buy a keyless or
keyed chuck for a lathe. If I'm just drilling a hole,
keyless is just fine. Putting a tap in the keyless
and tapping wouldn't be a problem because you are
still going forward. But when you put the lathe
in reverse to remove the tap, would the tap
loosen in the chuck? I would assume that there
is less resistance pulling the tap out, so maybe
it wouldn't loosen. Also I assume if it did
loosen, the worse that could happen is I'd
have to remove the tap by hand.

So I'm looking to those with the experience
to help me decide.

Thanks,
Wayne
Occasionally the keyless chuck (Albrecht)loosens up when reversing.
All I do is put a little tightening torque on it by hand while reversing
and it holds fine. I'd never give up the keyless just for this reason.

In article 51701a28.0405121708.78d0be37
@posting.google.com, says...
Sometime back one of our esteemed members posted that
if his machine had reverse, that he would only use a
keyed chuck on that machine.


I regularly power tap up to 3/8-16 in the mill with a 1/2"
Albrecht chuck--it works just fine. (Before installing a
VFD I plug reversed with a static converter for many years
when power tapping, which is also contrary to RCM dogma.)

A keyless chuck that's worn and/or been greased in the
wrong places may cause problems. The chuck will feel
springy when being tightened and release too easily when
reversed.

Ned Simmons

On Wed, 12 May 2004 23:32:38 -0400, Ned Simmons wrote:

In article 51701a28.0405121708.78d0be37
, says...
Sometime back one of our esteemed members posted that
if his machine had reverse, that he would only use a
keyed chuck on that machine.


I regularly power tap up to 3/8-16 in the mill with a 1/2"
Albrecht chuck--it works just fine. (Before installing a
VFD I plug reversed with a static converter for many years
when power tapping, which is also contrary to RCM dogma.)

A keyless chuck that's worn and/or been greased in the
wrong places may cause problems. The chuck will feel
springy when being tightened and release too easily when
reversed.

Ned Simmons

Ive pretty much stopped using keyless chucks on my mills when tapping as
it seems they nearly always slip for me. So Ive reglegated them to the
drill press or drilling only..which can be a problem as Ive a lot of
screw machine drill bits (left handed)

Gunner

"A vote for Kerry is a de facto vote for bin Laden."
Strider

In article ,
says...
On Wed, 12 May 2004 23:32:38 -0400, Ned Simmons wrote:


A keyless chuck that's worn and/or been greased in the
wrong places may cause problems. The chuck will feel
springy when being tightened and release too easily when
reversed.



Ive pretty much stopped using keyless chucks on my mills when tapping as
it seems they nearly always slip for me.

You can often improve a keyless chuck that releases too
easily. Disassemble and degrease the parts. Check for
burnishing on the conical surface inside the hood where the
jaws ride. Scuff up that surface with crocus if you can see
shiny tracks from the jaws. Relube the parts before
reassembling, but do not get any grease on the inside of
the hood or the mating surface of the jaws.

Ned Simmons

You can often improve a keyless chuck that releases too
easily. Disassemble and degrease the parts. Check for
burnishing on the conical surface inside the hood where the
jaws ride. Scuff up that surface with crocus if you can see
shiny tracks from the jaws. Relube the parts before
reassembling, but do not get any grease on the inside of
the hood or the mating surface of the jaws.

Ned Simmons

Ned,
Translation for us Brits please.
What is crocus?

John

"John Manders" wrote in message
...
You can often improve a keyless chuck that releases too
easily. Disassemble and degrease the parts. Check for
burnishing on the conical surface inside the hood where the
jaws ride. Scuff up that surface with crocus if you can see
shiny tracks from the jaws. Relube the parts before
reassembling, but do not get any grease on the inside of
the hood or the mating surface of the jaws.

Ned Simmons

Ned,
Translation for us Brits please.
What is crocus?

John



Presumably crocus powder or jewellers rouge - a very fine abrasive
consisting of ferric oxide

Andrew Mawson
Bromley, Kent, UK

In article ,
Gunner wrote:
On Wed, 12 May 2004 23:32:38 -0400, Ned Simmons wrote:

In article 51701a28.0405121708.78d0be37
, says...

[ ... ]

A keyless chuck that's worn and/or been greased in the
wrong places may cause problems. The chuck will feel
springy when being tightened and release too easily when
reversed.

Ned Simmons

Ive pretty much stopped using keyless chucks on my mills when tapping as
it seems they nearly always slip for me. So Ive reglegated them to the
drill press or drilling only..which can be a problem as Ive a lot of
screw machine drill bits (left handed)

There are special Albrecht chucks with diamond grit in the jaw
faces, designed to grip hardened shanks like mill shanks or taps.

There are also Albrecht chucks with a locking ring to prevent
unintended loosening.

However, swapping in a Jacobs geared chuck is cheaper. :-)

And I would use a TapMatic tapping head on the mill, just as I
do on the drill press -- unless I had a CNC which could measure the
angular rotation of the spindle, and feed proportionally, and do the
same in reverse for rigid tapping.

Enjoy,
DoN.
--
Email: | Voice (all times): (703) 938-4564
(too) near Washington D.C. | http://www.d-and-d.com/dnichols/DoN.html
--- Black Holes are where God is dividing by zero ---

Wayne wrote:

Sometime back one of our esteemed members posted that
if his machine had reverse, that he would only use a
keyed chuck on that machine.

I've been pretty much spoiled by keyless chucks.
I'm trying to decide whether to buy a keyless or
keyed chuck for a lathe. If I'm just drilling a hole,
keyless is just fine. Putting a tap in the keyless
and tapping wouldn't be a problem because you are
still going forward. But when you put the lathe
in reverse to remove the tap, would the tap
loosen in the chuck? I would assume that there
is less resistance pulling the tap out, so maybe
it wouldn't loosen. Also I assume if it did
loosen, the worse that could happen is I'd
have to remove the tap by hand.

So I'm looking to those with the experience
to help me decide.

Thanks,
Wayne

Depending on the size of taps you are using, keyless can be a good or
not so good choice. Every time the grip is loosened by the action of the
tool, whether from reversal or slipping in forward, the chuck jaws get
some amount of damage. An Albrecht is an expensive tap holder. I'm not
saying I don't use my Albrechts to tap, just use discretion.

Some time ago, when using a 3/4" keyed chuck to hold 7/8 and 23 mm taps
in the tailstock to tap chromo, I would get slippage. On investigation,
I learned that Morse taper tap drivers have been available since before
I was born.g Look ma, no more slippage.

michael