My dad is getting up in the years and is cleaning out some of his
unused/nolonger used tools. He gave me a 8" 4 jaw chuck that was made in
Germany. It has never been used and will need a backing plate. It is a 4 jaw
with self centering jaws, I have not come across any of these in my travels.
It must work well with square stock and would work just as good as a 3 jaw
on round stock, any other things I am mising?

Actually, if you use a good dial indicator with a four jaw chuck, you can
turn perfectly round stock. (zero runout)
If you do the same thing, you can turn a round post on square stock(good for
cam lobes), or elliptical lobes for whatever....
nice thing to have for extra precison... good luck.

"Waynemak" wrote in message
...
My dad is getting up in the years and is cleaning out some of his
unused/nolonger used tools. He gave me a 8" 4 jaw chuck that was made in
Germany. It has never been used and will need a backing plate. It is a 4
jaw with self centering jaws, I have not come across any of these in my
travels. It must work well with square stock and would work just as good
as a 3 jaw on round stock, any other things I am mising?

On 2005-03-07, Rob Newman wrote:
Actually, if you use a good dial indicator with a four jaw chuck, you can
turn perfectly round stock. (zero runout)
If you do the same thing, you can turn a round post on square stock(good for
cam lobes), or elliptical lobes for whatever....

None of those things is true of a 4-jaw *self-centering* chuck, which is
what the guy was talking about.

--
Ben Jackson

http://www.ben.com/

"Rob Newman" wrote in message
...
Actually, if you use a good dial indicator with a four jaw chuck, you can
turn perfectly round stock. (zero runout)
If you do the same thing, you can turn a round post on square stock(good
for
cam lobes), or elliptical lobes for whatever....
nice thing to have for extra precison... good luck.



Ah!
But not with this one! This is a universal 4 jaw, not an independent 4 jaw.
Very nice for gripping square objects, but inclined to grip only with three
jaws, or, really, two. The moment you move away from 3 point contact,
things get more complicated where chucks are concerned, unless they are
independent. It likely would not perform as well as a three jaw chuck with
round stock due to the tightest jaws gripping, with the set at 90 degrees
gripping, or not. In a perfect world they make sense. In practice, they
may not.

Harold

Waynemak wrote:

My dad is getting up in the years and is cleaning out some of his
unused/nolonger used tools. He gave me a 8" 4 jaw chuck that was made in
Germany. It has never been used and will need a backing plate. It is a 4 jaw
with self centering jaws, I have not come across any of these in my travels.
It must work well with square stock and would work just as good as a 3 jaw
on round stock, any other things I am mising?


Sounds like a strong gripper - just a notch above a 3.
Likely used on square stock that went to rounds. (Typical in wood).

Is is a wood chuck ? - might not be as strong as a steel use chuck.

Martin

--
Martin Eastburn, Barbara Eastburn
@ home at Lion's Lair with our computer
NRA LOH, NRA Life
NRA Second Amendment Task Force Charter Founder

Its a heavy chuck the name is klopfer. The chuck is about 30% heavier than
my 8" 4 jaw independent. Looks to be top quality.
"Martin H. Eastburn" wrote in message
. ..
Waynemak wrote:

My dad is getting up in the years and is cleaning out some of his
unused/nolonger used tools. He gave me a 8" 4 jaw chuck that was made in
Germany. It has never been used and will need a backing plate. It is a 4
jaw with self centering jaws, I have not come across any of these in my
travels. It must work well with square stock and would work just as good
as a 3 jaw on round stock, any other things I am mising?
Sounds like a strong gripper - just a notch above a 3.
Likely used on square stock that went to rounds. (Typical in wood).

Is is a wood chuck ? - might not be as strong as a steel use chuck.

Martin

--
Martin Eastburn, Barbara Eastburn
@ home at Lion's Lair with our computer
NRA LOH, NRA Life
NRA Second Amendment Task Force Charter Founder

How much wood would a wood chuck chuck?

--
Bob (Chief Pilot, White Knuckle Airways)


"Martin H. Eastburn" wrote in message
. ..

Is is a wood chuck ? - might not be as strong as a steel use chuck.

I have a 4-jaw scrolling lathe chuck. Each jaw is independantly adjustable
just like a normal 4J but there is also a scroll so once you get it dialed
in you can back it out and go back in. Mine is made by Rohm or someone and
cost nearly $1400 new which is a lot for a 6" chuck. No way is this one
made for wood. I think you can still see these in the MSC catalog. Wear
diapers -- the prices are *astronomical*. I got mine on ebay before it got
"discovered" and the prices skyrocketed.

GWE

Harold and Susan Vordos wrote:
"Rob Newman" wrote in message
...
Actually, if you use a good dial indicator with a four jaw chuck,
you can
turn perfectly round stock. (zero runout)
If you do the same thing, you can turn a round post on square
stock(good
for
cam lobes), or elliptical lobes for whatever....
nice thing to have for extra precison... good luck.



Ah!
But not with this one! This is a universal 4 jaw, not an independent
4 jaw.
Very nice for gripping square objects, but inclined to grip only with
three
jaws, or, really, two. The moment you move away from 3 point
contact,
things get more complicated where chucks are concerned, unless they
are
independent. It likely would not perform as well as a three jaw
chuck with
round stock due to the tightest jaws gripping, with the set at 90
degrees
gripping, or not. In a perfect world they make sense. In practice,
they
may not.

Harold

I find a wrapping of paper makes such a chuck grip more reliably.

I refinished a Harbor Freight cheapie four inch four jaw universal
chuck with Clover Compound. It took hours. I removed the scroll and
pushed each jaw through each slot in both directions, both
orientations, using a 1/2 ton arbor press until things started evening
up, then I got the grit out with a toothbrush. Yes, it was so tight it
needed the arbor press; finger pressure wouldn't do it. The work was
intensely boring: press, reverse, press, repeat, count jaws, move to
other slot, count jaws, etc....

Sad, though, you can never get all the grit out. It sure works smoothly
now, but how long will it last? It was for circular milling and hole
pattern drilling on a 20 mm dowel pin, and could use a brass bush for
the dowel pin.

I still have this chuck but we are in extreme cluter mode, not quite a
hoarding situation, and I wonder if I will ever use it. We (Teri and I)
may choose to pay somebody to help us sort out this crunch. We do have
a shredder.

The paper adds elasticity to the grip and can completely remove the
"overcontstrained" condition. Three point contact and all that
kinematic design stuff. I love four jaw self-centering chucks. They
work really well with wood and plastic; no shim is needed because the
work is so elastic.

A modification to a standard four jaw independent chuck is to procure
hex stock or a Balldriver that fits the screws, then drill the interior
to allow this long, skinny tool to adjust two jaws at once. With a
total redesign, you'd have a self-centering independent chuck. With the
mod, you have a quick-centering four jaw chuck. Wups. There goes
another patentable invention. Left and right threaded screws on
opposing jaws....

Yours,

Doug Goncz
Replikon Research
Seven Corners, VA 22044-0394

wrote:

Harold and Susan Vordos wrote:


"Rob Newman" wrote in message
...


Actually, if you use a good dial indicator with a four jaw chuck,


you can


turn perfectly round stock. (zero runout)
If you do the same thing, you can turn a round post on square


stock(good


for


cam lobes), or elliptical lobes for whatever....
nice thing to have for extra precison... good luck.



Ah!
But not with this one! This is a universal 4 jaw, not an independent


4 jaw.


Very nice for gripping square objects, but inclined to grip only with


three


jaws, or, really, two. The moment you move away from 3 point


contact,


things get more complicated where chucks are concerned, unless they


are


independent. It likely would not perform as well as a three jaw


chuck with


round stock due to the tightest jaws gripping, with the set at 90


degrees


gripping, or not. In a perfect world they make sense. In practice,


they


may not.

Harold



I find a wrapping of paper makes such a chuck grip more reliably.

I refinished a Harbor Freight cheapie four inch four jaw universal
chuck with Clover Compound. It took hours. I removed the scroll and
pushed each jaw through each slot in both directions, both
orientations, using a 1/2 ton arbor press until things started evening
up, then I got the grit out with a toothbrush. Yes, it was so tight it
needed the arbor press; finger pressure wouldn't do it. The work was
intensely boring: press, reverse, press, repeat, count jaws, move to
other slot, count jaws, etc....

Sad, though, you can never get all the grit out. It sure works smoothly
now, but how long will it last? It was for circular milling and hole
pattern drilling on a 20 mm dowel pin, and could use a brass bush for
the dowel pin.

I still have this chuck but we are in extreme cluter mode, not quite a
hoarding situation, and I wonder if I will ever use it. We (Teri and I)
may choose to pay somebody to help us sort out this crunch. We do have
a shredder.

The paper adds elasticity to the grip and can completely remove the
"overcontstrained" condition. Three point contact and all that
kinematic design stuff. I love four jaw self-centering chucks. They
work really well with wood and plastic; no shim is needed because the
work is so elastic.

A modification to a standard four jaw independent chuck is to procure
hex stock or a Balldriver that fits the screws, then drill the interior
to allow this long, skinny tool to adjust two jaws at once. With a
total redesign, you'd have a self-centering independent chuck. With the
mod, you have a quick-centering four jaw chuck. Wups. There goes
another patentable invention. Left and right threaded screws on
opposing jaws....

Yours,

Doug Goncz
Replikon Research
Seven Corners, VA 22044-0394



4 jaw scroll can also be good if you have to bore a sprocket or gear
that has a tooth count divisible by 4 and have to grab the tooth
gullets. Not the kind of thing you may do every day but when you need
it, it can save one hell of a lot of fiddling.

Koz

"Koz" wrote in message
...
snip------

4 jaw scroll can also be good if you have to bore a sprocket or gear
that has a tooth count divisible by 4 and have to grab the tooth
gullets. Not the kind of thing you may do every day but when you need
it, it can save one hell of a lot of fiddling.

Koz

This is an excellent example of where soft jaws shine. Concentricity can
be very reliably established, assuming the gear or sprocket was established
concentric with the major diameter originally. The added benefit of soft
jaws is the ability to locate your parts time and again at a perfect right
angle, assuming you make the jaws properly.

Harold

"Grant Erwin" wrote in message
...
I have a 4-jaw scrolling lathe chuck. Each jaw is independantly adjustable
just like a normal 4J but there is also a scroll so once you get it dialed
in you can back it out and go back in. Mine is made by Rohm or someone and
cost nearly $1400 new which is a lot for a 6" chuck. No way is this one
made for wood. I think you can still see these in the MSC catalog. Wear
diapers -- the prices are *astronomical*. I got mine on ebay before it got
"discovered" and the prices skyrocketed.

GWE

That makes a useful tool from one that is basically useless.

Harold

Bob Chilcoat wrote:

How much wood would a wood chuck chuck?

--
Bob (Chief Pilot, White Knuckle Airways)


"Martin H. Eastburn" wrote in message
. ..

Is is a wood chuck ? - might not be as strong as a steel use chuck.




Some of the largest were 24' columns. Hand tapered. That was some chunk of wood.
Martin

--
Martin Eastburn, Barbara Eastburn
@ home at Lion's Lair with our computer
NRA LOH, NRA Life
NRA Second Amendment Task Force Charter Founder