Hello all,

I was pretty heavily slammed shortly after the lathe's arrival, so I do
not recall how much I posted about it. Just in case, a brief re-cap,
and then a question.

My Enco 12x36 lathe lives! Rigging it was not too bad, though I was
wise to be suspicious about the connection of the skid (bolted to the
lathe) and the pallet: there was none other than the straps around the
crate that was built onto the skid! I ended up starting with a floor
jack to crib the skid and then slowly cut the pallet away to make room
for my engine hoist's legs. Once it was balanced in the slings, I
decided to go for and had the (already assembled) stand under it in a
few minutes. It was late, so the next day, I raised it slightly off the
ground and used 2x4 as a pry-bar to nudge the hoist across the garage to
its current location.

There was very little grit in the headstock, though there was a stray
machine screw. After some searching, it appears to have been a lost
screw of the type used to hold some of the front trim.

I built a 220 extension cord with a 15 amp double throw breaker in a $10
box to get it running.

So far, I have turned a little Al tubing, and noted that the 3-jaw chuck
(the only one I have used so far) was not running true. It appears to
be due to the pins on the back of the chuck. It was mounted to the
spindle when the lathe was shipped, and I suspect that either two of
them was installed too short, or one was left too long. It might have
been assembled that way due to some grit inside the hole receiving the
long pin. After some cleaning, I started to get it to sit down as far
as the other two pins _after_ my reassembly.

The chuck no longer runs untrue, but that is primarily because it no
longer mounts to the spindle I assume that I now have all three pins
at incorrect extension, probably screwed too far into the chuck body.

Unless the Chinese part of the instructions with my 4-jaw tells how to
mount the pins, I am w/o specifications. What is the correct way
(height at which, number of turns, etc.) to mount them?

Thanks,

Bill

Unless the Chinese part of the instructions with my 4-jaw tells how to
mount the pins, I am w/o specifications. �What is the correct way
(height at which, number of turns, etc.) to mount them?

Thanks,
Bill

Bill

The instructions go something like this.

When attaching the chuck to the spindle, the cams/tighteners should
turn about 135 degrees. At least mine do. There are some marks on the
spindle for this. If they don't turn far enough the corresponding pin
is into the chuck backing plate too far. Turn more than half a turn
the pin is not into the backing plate far enough. Adjust accordingly.
Everything does need to be clean.

I would think there are instructions on the Enco site for this.

Bob AZ

.

Unless the Chinese part of the instructions with my 4-jaw tells how to
mount the pins, I am w/o specifications. �What is the correct way
(height at which, number of turns, etc.) to mount them?

Thanks,

Bill

This should help:

http://www.practicalmachinist.com/vb...d.php?p=856062

Bob AZ

Bill Schwab wrote:

Unless the Chinese part of the instructions with my 4-jaw tells how to
mount the pins, I am w/o specifications. Â*What is the correct way
(height at which, number of turns, etc.) to mount them?

The CamLock pin should have a groove near the end of the thread. screw in
until the groove is flush with the chucks back +/- one turn.
The lock on the spindle nose has to be tight within 90° to 180° of rotation.
Adjust pin on the chuck accordingly.


Nick
--
The lowcost-DRO:
http://www.yadro.de

On May 3, 9:38*pm, Bill Schwab wrote:
So far, I have turned a little Al tubing, and noted that the 3-jaw chuck
(the only one I have used so far) was not running true. *
Bill

3-jaw chucks don't center the work perfectly anyway, and they get
worse as they wear. Their advantage is convenience. Use a 4-jaw for
accuracy and also when you need to tighten the jaws hard.
Jim Wilkins

Jim,

On May 3, 9:38 pm, Bill Schwab wrote:
So far, I have turned a little Al tubing, and noted that the 3-jaw chuck
(the only one I have used so far) was not running true.
Bill

3-jaw chucks don't center the work perfectly anyway, and they get
worse as they wear. Their advantage is convenience. Use a 4-jaw for
accuracy and also when you need to tighten the jaws hard.
Jim Wilkins

Understood. The runout on 3-jaw chucks can be pretty large, but I am
not trying to re-chuck anything yet, just learning how to get a good
finish and getting a feel for the machine. However, this was not a dial
indicator decision: one could see the chuck wobble from across the room.
One of the pin holes was quite gritty, and my hunch is that they
install the pin by feel: bottom out and then back off a certain number
of turns, so the gritty hole ended up bottoming out early and the pin
was "long" as a result - at least that would explain what happened. I
might still have some work to do, but it is a lot happier than it was,
simply by cleaning, re-inserting, and backing off one turn at a time
until the cams worked nicely.

The 4-jaw chuck will get a workout as I learn my way around the machine.
So far, I have been getting a feel for the gears. The feed levers
were particularly stubborn. The right (numbered) lever is easy enough
to move by turning the spindle. The left (lettered) feed lever was
tougher to move. The only easy way I have found to move it is to
manually turn the feed shaft. I have not tried threading yet, so I
assume one might have to turn the screw when it is engaged.

For those who might jump in with saged advice, it is an Enco 12x36
geared head lathe.

Bill

Nick,

Bill Schwab wrote:

Unless the Chinese part of the instructions with my 4-jaw tells how to
mount the pins, I am w/o specifications. What is the correct way
(height at which, number of turns, etc.) to mount them?

The CamLock pin should have a groove near the end of the thread. screw in
until the groove is flush with the chucks back +/- one turn.

Pretty sure I got it, and at least one of them looks a little deep,
consistent with a slightly short turn on the cam. I should be able to
get it right now.



The lock on the spindle nose has to be tight within 90° to 180° of rotation.
Adjust pin on the chuck accordingly.

Got it.

Thanks!

Bill

Bob,
.
Unless the Chinese part of the instructions with my 4-jaw tells how to
mount the pins, I am w/o specifications. �What is the correct way
(height at which, number of turns, etc.) to mount them?

Thanks,

Bill

This should help:

http://www.practicalmachinist.com/vb...d.php?p=856062

It did! When they refer to indicating "the cone," is that inside the
chuck "below" the jaws? Correct me if I am wrong, but that seems to be
overkill with a 3-jaw chuck?? It also would be unlikely to work well or
at all on the fairly rough surface that I suspect one would use. My
4-jaw chuck is behind a tool cabinet that needs to be moved to a new
home (making room for a bigger one purchased recently), and while I
think I could lift it more directly, I am going to be smarter than that
It would not surprise me to find a finished surface inside the 4-jaw.

That thread mentions using a torque wrench on the cams. Any takers, or
is that going too far? If you do use one, what is your target torque?

Thanks,

Bill

Bill Schwab wrote:

This should help:

http://www.practicalmachinist.com/vb...d.php?p=856062


It did! When they refer to indicating "the cone," is that inside the
chuck "below" the jaws? Correct me if I am wrong, but that seems to be
overkill with a 3-jaw chuck??

I'm not an expert on D1-anything, but I do have a Sheldon lathe
with D1-6 and several chucks, backplates, etc. for it. The
chuck (or back plate) has both a face and a taper that are BOTH
supposed to seat to the spindle face. The taper of the chuck is
a "female" taper that seats on a very short male taper on the
spindle. You need the tapers to mate closely to get repeatable
mounting of the chuck. You might check these with blue spotting
dye. You probably don't need to actually lock the cams to get
an impression on the tapers. I'd put the dye on the chuck,
because the male taper of the spindle will be easier to inspect.
Of course, you should get even transfer of the dye all around
the spindle. You can also apply dye to the face of the chuck
and see how well that seats against the spindle face. Again, it
should fit relatively well, rather than at just a few points.

You said something about indicating the rough surface of the
chuck ID. If thre is no ground taper on the back ID of the
chuck or backplate, then I really don't think it can be called a
D1 mount. It fits the machine's spindle, but it can't be
mounted repeatably. I can't imagine using such a contraption.
My Phase-II knockoff of the Buck Adjust-Tru chuck will grip any
size round with less than .001" runout. (Yes, I bought it new,
on sale, and it was a fine investment!) I took the backplate
off a wrecked real Buck chuck that came with the lathe.

D1 mounts usually have an orientation mark, where one pin is
marked to line up with one of the cams. usually there is an
extra straight line by that one cam.

If the external taper on the spindle is not true, then you
really have a problem. If it is true, and the dye indicates the
backplate is fitting well to the face and taper, than mount the
backplatew without the chuck and face it until it completely
cleans up the front of the backplate. Then try remounting the
chuck and see if it is better.

As for camlock torque, I just use the usual chuck wrench and
make it snug. I tighen them all up a little at a time, maybe
going around the spindle 3 times.

Jon

On Sun, 04 May 2008 12:37:12 -0500, Jon Elson
wrote:

Bill Schwab wrote:

This should help:

http://www.practicalmachinist.com/vb...d.php?p=856062


It did! When they refer to indicating "the cone," is that inside the
chuck "below" the jaws? Correct me if I am wrong, but that seems to be
overkill with a 3-jaw chuck??


You said something about indicating the rough surface of the
chuck ID. If thre is no ground taper on the back ID of the
chuck or backplate, then I really don't think it can be called a
D1 mount.

The document in the link above is from Jacobs, so I think it's likely
the instructions are for mounting a Rubberflex chuck and the "cone" is
the seating surface for the collets.

--
Ned Simmons

Jon,

You said something about indicating the rough surface of the chuck ID.
If thre is no ground taper on the back ID of the chuck or backplate,
then I really don't think it can be called a D1 mount. It fits the
machine's spindle, but it can't be mounted repeatably. I can't imagine
using such a contraption.

The back ID is very clean, but if I follow you, there is no way to get
to it with an indicator when the chuck is mounted on the spindle. The
surfaces that are reachable are ok, but they are far from hardened and
ground.

It seems to be running just fine now; again the problem was that the
pins were (incorrectly) pre-mounted and the 3-jaw chuck was installed on
the spindle in the crate.


D1 mounts usually have an orientation mark, where one pin is marked to
line up with one of the cams. usually there is an extra straight line
by that one cam.

Thanks, I will look for that. As with my mill a while ago, it is
getting to be time for some directed light. The overhead lighting above
and behind me doesn't cut it.

Bill

Jon Elson wrote:
Bill Schwab wrote:

This should help:

http://www.practicalmachinist.com/vb...d.php?p=856062


It did! When they refer to indicating "the cone," is that inside the
chuck "below" the jaws? Correct me if I am wrong, but that seems to
be overkill with a 3-jaw chuck??

I'm not an expert on D1-anything, but I do have a Sheldon lathe with
D1-6 and several chucks, backplates, etc. for it. The chuck (or back
plate) has both a face and a taper that are BOTH supposed to seat to
the spindle face. The taper of the chuck is a "female" taper that
seats on a very short male taper on the spindle. You need the tapers
to mate closely to get repeatable mounting of the chuck. You might
check these with blue spotting dye. You probably don't need to
actually lock the cams to get an impression on the tapers. I'd put
the dye on the chuck, because the male taper of the spindle will be
easier to inspect.
Of course, you should get even transfer of the dye all around the
spindle. You can also apply dye to the face of the chuck and see how
well that seats against the spindle face. Again, it should fit
relatively well, rather than at just a few points.

You said something about indicating the rough surface of the chuck
ID. If thre is no ground taper on the back ID of the chuck or
backplate, then I really don't think it can be called a D1 mount. It
fits the machine's spindle, but it can't be mounted repeatably. I
can't imagine using such a contraption.

I bought a cheap D1-4 mount and it had a turned taper instead of ground,
for what I was using it for it was fine as great accuracy was not
required. I will be wary of that supplier in future though and have
bought more expensive, not by a great amount, D1-4 mounts which have
ground location taper and face, I would buy those for anything accurate.
The cheap one also had one of the camlock pin locking screw holes
mis-drilled, re-drilled, and a thread insert to correct it.

My Phase-II knockoff of the Buck Adjust-Tru chuck will grip any size
round with less than .001" runout. (Yes, I bought it new, on sale,
and it was a fine investment!) I took the backplate off a wrecked
real Buck chuck that came with the lathe.

D1 mounts usually have an orientation mark, where one pin is marked to
line up with one of the cams. usually there is an extra straight line
by that one cam.

If the external taper on the spindle is not true, then you really have
a problem. If it is true, and the dye indicates the backplate is
fitting well to the face and taper, than mount the backplatew without
the chuck and face it until it completely cleans up the front of the
backplate. Then try remounting the chuck and see if it is better.

As for camlock torque, I just use the usual chuck wrench and make it
snug. I tighen them all up a little at a time, maybe going around the
spindle 3 times.

Jon