Re: Bad Chuck - Can it be Solved
On 12/18/24 21:15, Guy Edkins wrote: do know the jaws are numbered and they only go in a
certain slot. The jaws have discernible numbers, but the
slots in the chuck only show where number 1 jaw goes. The
other two are at best, vague. When installing the jaws
sequentially into the scroll thread does # 1 go first
followed by #2, etc. or do they start at the same time? With all jaws out, crank the pinions until the outer scroll tooth approaches slot one.? Back off a bit.? Insert jaw #1, hold against the scroll and advance the pinion until it grabs jaw 1.? Advance pinion until scroll tooth approaches next slot, that is #2. Insert jaw # 2, repeat for next slot and jaw # 3.? Really, there is no need to have slots 2 and 3 numbered, they just follow after slot #1.? And, the only reason to have slot 1 marked is to make sure you have the jaws in the same slots they were in when the initial jaw grinding was done. Jon
|
Re: Bad Chuck - Can it be Solved
On 12/18/24 15:22, Guy Edkins wrote: ?
?Hi all,
I am in the process of rehabbing a 3995 lathe. It was free
and maybe I now know why. The runout on the spindle inner
and outer diameter is really good. Like .0013. Screw on
the chuck and chuck up a mandrel and it all goes bad,
really bad. You can see it, let alone measure it. The
chuck is a Cushing 3 jaw.
So is it worth buying a new chuck, i.e. will it mitigate
much of the issue, or is there something else at play here
(see what I did there) that I have missed? I am new at
lathe details and the ins and outs, but an engineer by
background. Well, there are several possibilities.? First, see if there is wobble on the outside of the chuck body.? If not, then the problem is in the jaws.? If the outside of the chuck has wobble or runout, then the backplate needs to be faced true.? Possibly the register on the chuck side of the backplate also needs to be trued.? If you do that, then there will be looseness between the register and the chuck.? You might be able to put a shim in there, or make the "poor man's adjustable chuck".? Leave the chuck mounting bolts slightly loose, indicate a bar in the chuck, bump the chuck body until the bar runs true and then tighten the bolts. For severe runout, the chuck jaws may have been inserted into the wrong slots.? The jaws are numbered to match numbers on the slots.? If you put the wrong jaws in the wrong slots you will have huge runout.? If that is not the issue, the jaws may be "bell-mouthed", meaning worn more at the tips than farther back. This makes it hard to hold long stock securely.? The fix is to grind the inner faces of the jaws.? Usually some sort of "spider", putty or rubber bands are used to hold the jaws against the scroll face as it would be if holding a piece of work. One other gotcha is the possibility of a loose scroll.? Some chucks have a circular shim that centers the scroll in the body. If that had been lost, then the scroll will move around and the jaws won't hold anything on center. And, finally, if you can't find the source of this issue, then the chuck may have been crashed, and the grooves for the jaws may be bent.? There's really no way to fix that. Jon
|
Re: Bad Chuck - Can it be Solved
Here’s a YouTube video on converting a 3-jaw chuck into a ‘set-tru’ type:
|
Re: Bad Chuck - Can it be Solved
Yes, I did indicate backing plate od. Right about .0034. I had to avoid marking dimple for alignment to chuck itself. This leads me to believe it's a jaw issue with huge jump in runout.
Thanks, ?Guy Sent From iPad
toggle quoted message
Show quoted text
On Dec 18, 2024, at 11:10?PM, mike allen <animal@...> wrote:
?
They start differently , turn all 3 jaws over next to each other
& ya can see how their clocked . If I took my 3 jaws & put
then next to each other the tallest steps were different
thickness's . One of these days I'll get then setup in my mill
vise & get them all the same size & then see how far their
out & tune them up with the toll post grinder . Did ya run a
indicator on the outside of the chuck before ya dissected it .
Porbably should have mentioned that before .
animal
On 12/18/24 7:15 PM, Guy Edkins wrote:
I have successfully torn down the chuck fully, quite a bit of
chips in the small bevel gears that drive the scroll threads that
close the jaws. Chips elsewhere, but not a large number, (only
takes one in the right spot) so it maybe that this cleaning will
help. I do know the jaws are numbered and they only go in a
certain slot. The jaws have discernible numbers, but the slots in
the chuck only show where number 1 jaw goes. The other two are at
best, vague. When installing the jaws sequentially into the scroll
thread does # 1 go first followed by #2, etc. or do they start at
the same time?
Thanks, ?
Buy?
Sent From iPad
?
Before you even take it apart, verify the the jaws
are in the right slots (each jaw and each slot is
numbered)?
Also verify that each jaw was started
sequentially at the right time when assembled.?
Good luck?
Ray
On Dec 18, 2024, at
5:11?PM, David Ghilarducci via groups.io
<daveghil@...> wrote:
?
I found if you loosen the cap
screws on the back and tap them sequentially
with a brass hammer or even a ball peen
hammer you can usually split the chuck. ?
On Dec 18, 2024, at
3:40?PM, Guy Edkins via groups.io
<gedkins@...>
wrote:
?
I will see if I can get it apart. Tried
earlier. Backing plate is on tight. Thank
you for the info. Not giving up yet.?
Guy
Sent From iPad
?
the Sanou 3 jaw scroll chucks are
real nice chucks . I bought one
several years back due to my
Cushman chuck being all messed up
. I think I got it from These guys
# 0603F0 with soft jaws for @ 120
, ya still need a backplate unless
the one from the Cushman is
salvageable . Same folks have
backplatesfrom 40 bucks n up .
animal
On
12/18/24 2:40 PM, Bill in OKC too
via groups.io wrote:
First,
disassemble the chuck, clean
and lubricate it. Reassemble
it making sure the chuck
jaws go in the correct
slots, and started at the
correct times. Then try it
again.? A really good ?quality?3-jaw
self-centering chuck will
still have .003" of run-out.
There are a number of
schemes to let them be
adjusted to better run-out,
and both Buck and Cushing
use them on some of their
more expensive chucks. You
may have one of those that
has been opened up, and not
reset. Or the thing can be
incredibly dirty inside. Saw
a video yesterday that
showed a guy testing a
standard non-adjustable
Craftsman chuck. Which was
over .020" out. He ground
the jaws, then disassembled
it to clean it out. Cleaned
and reassembled, it was
right at .003" run-out.?
Here it is:?
I'd
do the cleaning and such
first! I have an atlas chuck
of my own that's .014" out.
Haven't been able to get
mine apart, yet.?
Bill
in OKC
William
R. Meyers, MSgt,
USAF(Ret.)
Aphorisms
to live by:
Good
judgement comes
from experience.
Experience comes
from bad
judgement.?
SEMPER
GUMBY!
Improvise,
Adapt, and
Overcome.
Physics
doesn't care about
your schedule.
The
only reason I know
anything is
because I've done
it wrong enough
times to START to
know better.
Expect
in one hand,
expectorate in
the other. See
which one gets
full first.
On Wednesday, December
18, 2024 at 04:27:42 PM CST,
Guy Edkins <gedkins@...>
wrote:
?Hi all,
I am in the process of
rehabbing a 3995 lathe. It
was free and maybe I now
know why. The runout on
the spindle inner and
outer diameter is really
good. Like .0013. Screw on
the chuck and chuck up a
mandrel and it all goes
bad, really bad. You can
see it, let alone measure
it. The chuck is a Cushing
3 jaw.
So is it worth buying a
new chuck, i.e. will it
mitigate much of the
issue, or is there
something else at play
here (see what I did
there) that I have missed?
I am new at lathe details
and the ins and outs, but
an engineer by background.
Sent From iPad
|
Re: Bad Chuck - Can it be Solved
They start differently , turn all 3 jaws over next to each other
& ya can see how their clocked . If I took my 3 jaws & put
then next to each other the tallest steps were different
thickness's . One of these days I'll get then setup in my mill
vise & get them all the same size & then see how far their
out & tune them up with the toll post grinder . Did ya run a
indicator on the outside of the chuck before ya dissected it .
Porbably should have mentioned that before .
animal
On 12/18/24 7:15 PM, Guy Edkins wrote:
toggle quoted message
Show quoted text
I have successfully torn down the chuck fully, quite a bit of
chips in the small bevel gears that drive the scroll threads that
close the jaws. Chips elsewhere, but not a large number, (only
takes one in the right spot) so it maybe that this cleaning will
help. I do know the jaws are numbered and they only go in a
certain slot. The jaws have discernible numbers, but the slots in
the chuck only show where number 1 jaw goes. The other two are at
best, vague. When installing the jaws sequentially into the scroll
thread does # 1 go first followed by #2, etc. or do they start at
the same time?
Thanks, ?
Buy?
Sent From iPad
?
Before you even take it apart, verify the the jaws
are in the right slots (each jaw and each slot is
numbered)?
Also verify that each jaw was started
sequentially at the right time when assembled.?
Good luck?
Ray
On Dec 18, 2024, at
5:11?PM, David Ghilarducci via groups.io
<daveghil@...> wrote:
?
I found if you loosen the cap
screws on the back and tap them sequentially
with a brass hammer or even a ball peen
hammer you can usually split the chuck. ?
On Dec 18, 2024, at
3:40?PM, Guy Edkins via groups.io
<gedkins@...>
wrote:
?
I will see if I can get it apart. Tried
earlier. Backing plate is on tight. Thank
you for the info. Not giving up yet.?
Guy
Sent From iPad
?
the Sanou 3 jaw scroll chucks are
real nice chucks . I bought one
several years back due to my
Cushman chuck being all messed up
. I think I got it from These guys
# 0603F0 with soft jaws for @ 120
, ya still need a backplate unless
the one from the Cushman is
salvageable . Same folks have
backplatesfrom 40 bucks n up .
animal
On
12/18/24 2:40 PM, Bill in OKC too
via groups.io wrote:
First,
disassemble the chuck, clean
and lubricate it. Reassemble
it making sure the chuck
jaws go in the correct
slots, and started at the
correct times. Then try it
again.? A really good ?quality?3-jaw
self-centering chuck will
still have .003" of run-out.
There are a number of
schemes to let them be
adjusted to better run-out,
and both Buck and Cushing
use them on some of their
more expensive chucks. You
may have one of those that
has been opened up, and not
reset. Or the thing can be
incredibly dirty inside. Saw
a video yesterday that
showed a guy testing a
standard non-adjustable
Craftsman chuck. Which was
over .020" out. He ground
the jaws, then disassembled
it to clean it out. Cleaned
and reassembled, it was
right at .003" run-out.?
Here it is:?
I'd
do the cleaning and such
first! I have an atlas chuck
of my own that's .014" out.
Haven't been able to get
mine apart, yet.?
Bill
in OKC
William
R. Meyers, MSgt,
USAF(Ret.)
Aphorisms
to live by:
Good
judgement comes
from experience.
Experience comes
from bad
judgement.?
SEMPER
GUMBY!
Improvise,
Adapt, and
Overcome.
Physics
doesn't care about
your schedule.
The
only reason I know
anything is
because I've done
it wrong enough
times to START to
know better.
Expect
in one hand,
expectorate in
the other. See
which one gets
full first.
On Wednesday, December
18, 2024 at 04:27:42 PM CST,
Guy Edkins <gedkins@...>
wrote:
?Hi all,
I am in the process of
rehabbing a 3995 lathe. It
was free and maybe I now
know why. The runout on
the spindle inner and
outer diameter is really
good. Like .0013. Screw on
the chuck and chuck up a
mandrel and it all goes
bad, really bad. You can
see it, let alone measure
it. The chuck is a Cushing
3 jaw.
So is it worth buying a
new chuck, i.e. will it
mitigate much of the
issue, or is there
something else at play
here (see what I did
there) that I have missed?
I am new at lathe details
and the ins and outs, but
an engineer by background.
Sent From iPad
|
Re: Bad Chuck - Can it be Solved
I have successfully torn down the chuck fully, quite a bit of chips in the small bevel gears that drive the scroll threads that close the jaws. Chips elsewhere, but not a large number, (only takes one in the right spot) so it maybe that this cleaning will help. I do know the jaws are numbered and they only go in a certain slot. The jaws have discernible numbers, but the slots in the chuck only show where number 1 jaw goes. The other two are at best, vague. When installing the jaws sequentially into the scroll thread does # 1 go first followed by #2, etc. or do they start at the same time?
toggle quoted message
Show quoted text
On Dec 18, 2024, at 9:21?PM, Ray Daniels via groups.io <rmdaniels47@...> wrote:
? Before you even take it apart, verify the the jaws are in the right slots (each jaw and each slot is numbered)? Also verify that each jaw was started sequentially at the right time when assembled.? Good luck? Ray On Dec 18, 2024, at 5:11?PM, David Ghilarducci via groups.io <daveghil@...> wrote:
? I found if you loosen the cap screws on the back and tap them sequentially with a brass hammer or even a ball peen hammer you can usually split the chuck. ? On Dec 18, 2024, at 3:40?PM, Guy Edkins via groups.io <gedkins@...> wrote:
? I will see if I can get it apart. Tried earlier. Backing plate is on tight. Thank you for the info. Not giving up yet.?
Guy Sent From iPad On Dec 18, 2024, at 6:00?PM, mike allen <animal@...> wrote:
?
the Sanou 3 jaw scroll chucks are real nice chucks . I bought one
several years back due to my Cushman chuck being all messed up . I
think I got it from These guys
# 0603F0 with soft jaws for @ 120 , ya still need a backplate
unless the one from the Cushman is salvageable . Same folks have
backplatesfrom 40 bucks n up .
animal
On 12/18/24 2:40 PM, Bill in OKC too
via groups.io wrote:
First, disassemble
the chuck, clean and lubricate it. Reassemble it making sure
the chuck jaws go in the correct slots, and started at the
correct times. Then try it again.? A really good ?quality?3-jaw
self-centering chuck will still have .003" of run-out. There
are a number of schemes to let them be adjusted to better
run-out, and both Buck and Cushing use them on some of their
more expensive chucks. You may have one of those that has
been opened up, and not reset. Or the thing can be
incredibly dirty inside. Saw a video yesterday that showed a
guy testing a standard non-adjustable Craftsman chuck. Which
was over .020" out. He ground the jaws, then disassembled it
to clean it out. Cleaned and reassembled, it was right at
.003" run-out.? Here it is:?
I'd do the
cleaning and such first! I have an atlas chuck of my own
that's .014" out. Haven't been able to get mine apart, yet.?
Bill in OKC
William
R. Meyers, MSgt, USAF(Ret.)
Aphorisms to live by:
Good judgement comes from experience.
Experience comes from bad judgement.?
SEMPER GUMBY!
Improvise, Adapt, and Overcome.
Physics doesn't care about your
schedule.
The only reason I know anything is
because I've done it wrong enough times to START
to know better.
Expect
in one hand, expectorate in the other. See
which one gets full first.
On Wednesday, December 18, 2024 at 04:27:42 PM CST, Guy
Edkins <gedkins@...> wrote:
?Hi all,
I am in the process of rehabbing a 3995 lathe. It was free
and maybe I now know why. The runout on the spindle inner
and outer diameter is really good. Like .0013. Screw on
the chuck and chuck up a mandrel and it all goes bad,
really bad. You can see it, let alone measure it. The
chuck is a Cushing 3 jaw.
So is it worth buying a new chuck, i.e. will it mitigate
much of the issue, or is there something else at play here
(see what I did there) that I have missed? I am new at
lathe details and the ins and outs, but an engineer by
background.
Sent From iPad
|
Re: Bad Chuck - Can it be Solved
Before you even take it apart, verify the the jaws are in the right slots (each jaw and each slot is numbered)? Also verify that each jaw was started sequentially at the right time when assembled.? Good luck?
toggle quoted message
Show quoted text
On Dec 18, 2024, at 5:11?PM, David Ghilarducci via groups.io <daveghil@...> wrote:
? I found if you loosen the cap screws on the back and tap them sequentially with a brass hammer or even a ball peen hammer you can usually split the chuck. ? On Dec 18, 2024, at 3:40?PM, Guy Edkins via groups.io <gedkins@...> wrote:
? I will see if I can get it apart. Tried earlier. Backing plate is on tight. Thank you for the info. Not giving up yet.?
Guy Sent From iPad On Dec 18, 2024, at 6:00?PM, mike allen <animal@...> wrote:
?
the Sanou 3 jaw scroll chucks are real nice chucks . I bought one
several years back due to my Cushman chuck being all messed up . I
think I got it from These guys
# 0603F0 with soft jaws for @ 120 , ya still need a backplate
unless the one from the Cushman is salvageable . Same folks have
backplatesfrom 40 bucks n up .
animal
On 12/18/24 2:40 PM, Bill in OKC too
via groups.io wrote:
First, disassemble
the chuck, clean and lubricate it. Reassemble it making sure
the chuck jaws go in the correct slots, and started at the
correct times. Then try it again.? A really good ?quality?3-jaw
self-centering chuck will still have .003" of run-out. There
are a number of schemes to let them be adjusted to better
run-out, and both Buck and Cushing use them on some of their
more expensive chucks. You may have one of those that has
been opened up, and not reset. Or the thing can be
incredibly dirty inside. Saw a video yesterday that showed a
guy testing a standard non-adjustable Craftsman chuck. Which
was over .020" out. He ground the jaws, then disassembled it
to clean it out. Cleaned and reassembled, it was right at
.003" run-out.? Here it is:?
I'd do the
cleaning and such first! I have an atlas chuck of my own
that's .014" out. Haven't been able to get mine apart, yet.?
Bill in OKC
William
R. Meyers, MSgt, USAF(Ret.)
Aphorisms to live by:
Good judgement comes from experience.
Experience comes from bad judgement.?
SEMPER GUMBY!
Improvise, Adapt, and Overcome.
Physics doesn't care about your
schedule.
The only reason I know anything is
because I've done it wrong enough times to START
to know better.
Expect
in one hand, expectorate in the other. See
which one gets full first.
On Wednesday, December 18, 2024 at 04:27:42 PM CST, Guy
Edkins <gedkins@...> wrote:
?Hi all,
I am in the process of rehabbing a 3995 lathe. It was free
and maybe I now know why. The runout on the spindle inner
and outer diameter is really good. Like .0013. Screw on
the chuck and chuck up a mandrel and it all goes bad,
really bad. You can see it, let alone measure it. The
chuck is a Cushing 3 jaw.
So is it worth buying a new chuck, i.e. will it mitigate
much of the issue, or is there something else at play here
(see what I did there) that I have missed? I am new at
lathe details and the ins and outs, but an engineer by
background.
Sent From iPad
|
Re: Bad Chuck - Can it be Solved
I found if you loosen the cap screws on the back and tap them sequentially with a brass hammer or even a ball peen hammer you can usually split the chuck. ?
toggle quoted message
Show quoted text
On Dec 18, 2024, at 3:40?PM, Guy Edkins via groups.io <gedkins@...> wrote:
? I will see if I can get it apart. Tried earlier. Backing plate is on tight. Thank you for the info. Not giving up yet.?
Guy Sent From iPad On Dec 18, 2024, at 6:00?PM, mike allen <animal@...> wrote:
?
the Sanou 3 jaw scroll chucks are real nice chucks . I bought one
several years back due to my Cushman chuck being all messed up . I
think I got it from These guys
# 0603F0 with soft jaws for @ 120 , ya still need a backplate
unless the one from the Cushman is salvageable . Same folks have
backplatesfrom 40 bucks n up .
animal
On 12/18/24 2:40 PM, Bill in OKC too
via groups.io wrote:
First, disassemble
the chuck, clean and lubricate it. Reassemble it making sure
the chuck jaws go in the correct slots, and started at the
correct times. Then try it again.? A really good ?quality?3-jaw
self-centering chuck will still have .003" of run-out. There
are a number of schemes to let them be adjusted to better
run-out, and both Buck and Cushing use them on some of their
more expensive chucks. You may have one of those that has
been opened up, and not reset. Or the thing can be
incredibly dirty inside. Saw a video yesterday that showed a
guy testing a standard non-adjustable Craftsman chuck. Which
was over .020" out. He ground the jaws, then disassembled it
to clean it out. Cleaned and reassembled, it was right at
.003" run-out.? Here it is:?
I'd do the
cleaning and such first! I have an atlas chuck of my own
that's .014" out. Haven't been able to get mine apart, yet.?
Bill in OKC
William
R. Meyers, MSgt, USAF(Ret.)
Aphorisms to live by:
Good judgement comes from experience.
Experience comes from bad judgement.?
SEMPER GUMBY!
Improvise, Adapt, and Overcome.
Physics doesn't care about your
schedule.
The only reason I know anything is
because I've done it wrong enough times to START
to know better.
Expect
in one hand, expectorate in the other. See
which one gets full first.
On Wednesday, December 18, 2024 at 04:27:42 PM CST, Guy
Edkins <gedkins@...> wrote:
?Hi all,
I am in the process of rehabbing a 3995 lathe. It was free
and maybe I now know why. The runout on the spindle inner
and outer diameter is really good. Like .0013. Screw on
the chuck and chuck up a mandrel and it all goes bad,
really bad. You can see it, let alone measure it. The
chuck is a Cushing 3 jaw.
So is it worth buying a new chuck, i.e. will it mitigate
much of the issue, or is there something else at play here
(see what I did there) that I have missed? I am new at
lathe details and the ins and outs, but an engineer by
background.
Sent From iPad
|
Re: Bad Chuck - Can it be Solved
I will see if I can get it apart. Tried earlier. Backing plate is on tight. Thank you for the info. Not giving up yet.?
toggle quoted message
Show quoted text
On Dec 18, 2024, at 6:00?PM, mike allen <animal@...> wrote:
?
the Sanou 3 jaw scroll chucks are real nice chucks . I bought one
several years back due to my Cushman chuck being all messed up . I
think I got it from These guys
# 0603F0 with soft jaws for @ 120 , ya still need a backplate
unless the one from the Cushman is salvageable . Same folks have
backplatesfrom 40 bucks n up .
animal
On 12/18/24 2:40 PM, Bill in OKC too
via groups.io wrote:
First, disassemble
the chuck, clean and lubricate it. Reassemble it making sure
the chuck jaws go in the correct slots, and started at the
correct times. Then try it again.? A really good ?quality?3-jaw
self-centering chuck will still have .003" of run-out. There
are a number of schemes to let them be adjusted to better
run-out, and both Buck and Cushing use them on some of their
more expensive chucks. You may have one of those that has
been opened up, and not reset. Or the thing can be
incredibly dirty inside. Saw a video yesterday that showed a
guy testing a standard non-adjustable Craftsman chuck. Which
was over .020" out. He ground the jaws, then disassembled it
to clean it out. Cleaned and reassembled, it was right at
.003" run-out.? Here it is:?
I'd do the
cleaning and such first! I have an atlas chuck of my own
that's .014" out. Haven't been able to get mine apart, yet.?
Bill in OKC
William
R. Meyers, MSgt, USAF(Ret.)
Aphorisms to live by:
Good judgement comes from experience.
Experience comes from bad judgement.?
SEMPER GUMBY!
Improvise, Adapt, and Overcome.
Physics doesn't care about your
schedule.
The only reason I know anything is
because I've done it wrong enough times to START
to know better.
Expect
in one hand, expectorate in the other. See
which one gets full first.
On Wednesday, December 18, 2024 at 04:27:42 PM CST, Guy
Edkins <gedkins@...> wrote:
?Hi all,
I am in the process of rehabbing a 3995 lathe. It was free
and maybe I now know why. The runout on the spindle inner
and outer diameter is really good. Like .0013. Screw on
the chuck and chuck up a mandrel and it all goes bad,
really bad. You can see it, let alone measure it. The
chuck is a Cushing 3 jaw.
So is it worth buying a new chuck, i.e. will it mitigate
much of the issue, or is there something else at play here
(see what I did there) that I have missed? I am new at
lathe details and the ins and outs, but an engineer by
background.
Sent From iPad
|
Re: Bad Chuck - Can it be Solved
the Sanou 3 jaw scroll chucks are real nice chucks . I bought one
several years back due to my Cushman chuck being all messed up . I
think I got it from These guys
# 0603F0 with soft jaws for @ 120 , ya still need a backplate
unless the one from the Cushman is salvageable . Same folks have
backplatesfrom 40 bucks n up .
animal
On 12/18/24 2:40 PM, Bill in OKC too
via groups.io wrote:
toggle quoted message
Show quoted text
First, disassemble
the chuck, clean and lubricate it. Reassemble it making sure
the chuck jaws go in the correct slots, and started at the
correct times. Then try it again.? A really good ?quality?3-jaw
self-centering chuck will still have .003" of run-out. There
are a number of schemes to let them be adjusted to better
run-out, and both Buck and Cushing use them on some of their
more expensive chucks. You may have one of those that has
been opened up, and not reset. Or the thing can be
incredibly dirty inside. Saw a video yesterday that showed a
guy testing a standard non-adjustable Craftsman chuck. Which
was over .020" out. He ground the jaws, then disassembled it
to clean it out. Cleaned and reassembled, it was right at
.003" run-out.? Here it is:?
I'd do the
cleaning and such first! I have an atlas chuck of my own
that's .014" out. Haven't been able to get mine apart, yet.?
Bill in OKC
William
R. Meyers, MSgt, USAF(Ret.)
Aphorisms to live by:
Good judgement comes from experience.
Experience comes from bad judgement.?
SEMPER GUMBY!
Improvise, Adapt, and Overcome.
Physics doesn't care about your
schedule.
The only reason I know anything is
because I've done it wrong enough times to START
to know better.
Expect
in one hand, expectorate in the other. See
which one gets full first.
On Wednesday, December 18, 2024 at 04:27:42 PM CST, Guy
Edkins <gedkins@...> wrote:
?Hi all,
I am in the process of rehabbing a 3995 lathe. It was free
and maybe I now know why. The runout on the spindle inner
and outer diameter is really good. Like .0013. Screw on
the chuck and chuck up a mandrel and it all goes bad,
really bad. You can see it, let alone measure it. The
chuck is a Cushing 3 jaw.
So is it worth buying a new chuck, i.e. will it mitigate
much of the issue, or is there something else at play here
(see what I did there) that I have missed? I am new at
lathe details and the ins and outs, but an engineer by
background.
Sent From iPad
|
Re: Bad Chuck - Can it be Solved
First, disassemble the chuck, clean and lubricate it. Reassemble it making sure the chuck jaws go in the correct slots, and started at the correct times. Then try it again.? A really good ?quality?3-jaw self-centering chuck will still have .003" of run-out. There are a number of schemes to let them be adjusted to better run-out, and both Buck and Cushing use them on some of their more expensive chucks. You may have one of those that has been opened up, and not reset. Or the thing can be incredibly dirty inside. Saw a video yesterday that showed a guy testing a standard non-adjustable Craftsman chuck. Which was over .020" out. He ground the jaws, then disassembled it to clean it out. Cleaned and reassembled, it was right at .003" run-out.? Here it is:?
I'd do the cleaning and such first! I have an atlas chuck of my own that's .014" out. Haven't been able to get mine apart, yet.?
Bill in OKC
William R. Meyers, MSgt, USAF(Ret.)
Aphorisms to live by: Good judgement comes from experience. Experience comes from bad judgement.? SEMPER GUMBY!
Expect in one hand, expectorate in the other. See which one gets full first.
On Wednesday, December 18, 2024 at 04:27:42 PM CST, Guy Edkins <gedkins@...> wrote:
?Hi all,
I am in the process of rehabbing a 3995 lathe. It was free and maybe I now know why. The runout on the spindle inner and outer diameter is really good. Like .0013. Screw on the chuck and chuck up a mandrel and it all goes bad, really bad. You can see it, let alone measure it. The chuck is a Cushing 3 jaw.
So is it worth buying a new chuck, i.e. will it mitigate much of the issue, or is there something else at play here (see what I did there) that I have missed? I am new at lathe details and the ins and outs, but an engineer by background.
Sent From iPad
|
Bad Chuck - Can it be Solved
?
?Hi all,
I am in the process of rehabbing a 3995 lathe. It was free and maybe I now know why. The runout on the spindle inner and outer diameter is really good. Like .0013. Screw on the chuck and chuck up a mandrel and it all goes bad, really bad. You can see it, let alone measure it. The chuck is a Cushing 3 jaw.
So is it worth buying a new chuck, i.e. will it mitigate much of the issue, or is there something else at play here (see what I did there) that I have missed? I am new at lathe details and the ins and outs, but an engineer by background.
Sent From iPad
|
Re: Wanting to buy AXA 250-111 - wanting opinions on which brand
Hemingway Kits also sells a couple different kits to make one ,
their quality is pretty top notch . They have a lot of different
kits
animal
On 12/18/24 10:47 AM, Bill in OKC too
via groups.io wrote:
toggle quoted message
Show quoted text
You can make your
own scissor knurler, too. Except the knurls. Unless you need
something special, in which case you can make them, too.
Depends how deep down that rabbit hole you want to go.? 
?
is a knurler you can make yourself, though they'll be
happy to sell you one, if you prefer to buy. Yes, it's
for mini-lathes, but most of the accessories I bought or
made for my HF 7x10 fit the Atlas TH42 as well. MT3
Spindles, and MT2 Tailstocks, for example...? Some
adapter plates for chucks and such.?
Bill in OKC
William
R. Meyers, MSgt, USAF(Ret.)
Aphorisms to live by:
Good judgement comes from experience.
Experience comes from bad judgement.?
SEMPER GUMBY!
Improvise, Adapt, and Overcome.
Physics doesn't care about your
schedule.
The only reason I know anything is
because I've done it wrong enough times to START
to know better.
Expect
in one hand, expectorate in the other. See
which one gets full first.
On Wednesday, December 18, 2024 at 10:43:56 AM CST,
Lbrewer42 via groups.io
<lbrewer_42@...> wrote:
As always, I really appreciate this site and the
members.? Thanks for the info.? I did look at Shars,
but in this case they are more expensive.? I think I
will look into, when I get more hours under my belt, a
scissors knurler.? I ordered the 10 piece system.?
Maybe changing the knurling tool to a scissors type
will be a future project for fun.? I also will
definitely take it apart (and take pics!) and clean it
first.
?
Merry Christmas!
|
Re: Wanting to buy AXA 250-111 - wanting opinions on which brand
I did just that in a class or two at Monroe Community College.? As the old guy auditing the course they pointed me at the donated drops supply and said make stuff for your shop.? The wheels came from Amazon for under $10 and seem to work fine on aluminum.? I haven't needed to do anything in steel yet but I don't think it will be a problem.? Pivots and wheel axles are 1/4" dowel pins, bolts are 1/4-20.?? I really should make a knob, the wooden one is from my CNC router clamps.? Arms should have been about 1/8# shorter, it is a bit tight to get onto the stock without opening it up all the way.
Dave
On Wed, Dec 18, 2024 at 1:47?PM Bill in OKC too via <wmrmeyers= [email protected]> wrote: You can make your own scissor knurler, too. Except the knurls. Unless you need something special, in which case you can make them, too. Depends how deep down that rabbit hole you want to go.?
? is a knurler you can make yourself, though they'll be happy to sell you one, if you prefer to buy. Yes, it's for mini-lathes, but most of the accessories I bought or made for my HF 7x10 fit the Atlas TH42 as well. MT3 Spindles, and MT2 Tailstocks, for example...? Some adapter plates for chucks and such.?
Bill in OKC
William R. Meyers, MSgt, USAF(Ret.)
Aphorisms to live by: Good judgement comes from experience. Experience comes from bad judgement.? SEMPER GUMBY!
Expect in one hand, expectorate in the other. See which one gets full first.
On Wednesday, December 18, 2024 at 10:43:56 AM CST, Lbrewer42 via <lbrewer_42= [email protected]> wrote:
As always, I really appreciate this site and the members.? Thanks for the info.? I did look at Shars, but in this case they are more expensive.? I think I will look into, when I get more hours under my belt, a scissors knurler.? I ordered the 10 piece system.? Maybe changing the knurling tool to a scissors type will be a future project for fun.? I also will definitely take it apart (and take pics!) and clean it first.
?
Merry Christmas!
|
I'm almost crying. It's WAY too big for my shop. Last Clausing Colchester I looked at, a 13", was $6900 a few years ago. The school where I used one also had Clausing Colchester 15" lathes. Pretty sure they would have crushed the slab in my shop. WHA!!!!
Bill in OKC
William R. Meyers, MSgt, USAF(Ret.)
Aphorisms to live by: Good judgement comes from experience. Experience comes from bad judgement.? SEMPER GUMBY!
Expect in one hand, expectorate in the other. See which one gets full first.
On Wednesday, December 18, 2024 at 11:10:50 AM CST, wa5jat/Jim Hudson via groups.io <jlhudson1@...> wrote:
FYI, $3000 in Union City , OK
?no connection
?
|
Re: Wanting to buy AXA 250-111 - wanting opinions on which brand
You can make your own scissor knurler, too. Except the knurls. Unless you need something special, in which case you can make them, too. Depends how deep down that rabbit hole you want to go.?
https://littlemachineshop.com/projects/knurler.php? is a knurler you can make yourself, though they'll be happy to sell you one, if you prefer to buy. Yes, it's for mini-lathes, but most of the accessories I bought or made for my HF 7x10 fit the Atlas TH42 as well. MT3 Spindles, and MT2 Tailstocks, for example...? Some adapter plates for chucks and such.?
Bill in OKC
William R. Meyers, MSgt, USAF(Ret.)
Aphorisms to live by: Good judgement comes from experience. Experience comes from bad judgement.? SEMPER GUMBY!
Expect in one hand, expectorate in the other. See which one gets full first.
On Wednesday, December 18, 2024 at 10:43:56 AM CST, Lbrewer42 via groups.io <lbrewer_42@...> wrote:
As always, I really appreciate this site and the members.? Thanks for the info.? I did look at Shars, but in this case they are more expensive.? I think I will look into, when I get more hours under my belt, a scissors knurler.? I ordered the 10 piece system.? Maybe changing the knurling tool to a scissors type will be a future project for fun.? I also will definitely take it apart (and take pics!) and clean it first.
?
Merry Christmas!
|
Re: Wanting to buy AXA 250-111 - wanting opinions on which brand
??? Forgot to mention that the Dog Point screws in each tool
holder are usually garbage , real soft screws . When I first got
my tool holder set I went to my hardware co & bought a bag of
100 new quality screws , thats enough for 25 tool holders .
animal
On 12/18/24 7:03 AM, William Burton via
groups.io wrote:
toggle quoted message
Show quoted text
I've bought many extra tool holders from Shars which are well
made and cheaper than most other suppliers.? I assume their tool
post would also be fine.? You'll get a "bump" knurler with the
set but, as others have said, you'll definitely want to get a
scissors knurler instead.? I altered the "bump" knurler that
came with my original set into a tool holder so it wouldn't go
to waste.?
|
FYI, $3000 in Union City , OK
?no connection
?
|
Re: Wanting to buy AXA 250-111 - wanting opinions on which brand
I've knurled a handful of things using the old, atlas lantern style tools and the QC one that came with my Phase II AXA tool post. Since then I've stopped trying until I get a scissors type made or bought. I find the off center pressure on the QCTP makes it creep out of square.
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Re: Wanting to buy AXA 250-111 - wanting opinions on which brand
The scissor type squeeze the part.? The other type PUSH on the part which puts strain on the bearings of the spindle.? Get the Scissor type or make one.? They are easy to make but have lots of parts for a newbie.? (NOt really)
|
Steven H
Bill in OKC too
wa5jat/Jim Hudson