I'm new to metalworking and just got a Microlux 7x14.
I'm interested in machining thin disks - about 1 1/2" in diameter by 1/16".

I see that that some lathes have soft jaws, such as
http://www.taigtools.com/c1051.html

Is there an equivalent solution for the Sieg lathe?
Any other ideas?

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Sending unsolicited commercial e-mail to this account incurs a fee of
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Bruce Barnett wrote:

I'm interested in machining thin disks - about 1 1/2" in diameter by 1/16".

What machining operations do you intend to do?
I often clamp disks between plasic/tuffnol "mushrooms" or glue them to a
mandrel (LockTite)

Nick
--
Motor Modelle // Engine Models
http://www.motor-manufaktur.de
DIY-DRO - YADRO - Eigenbau-Digitalanzeige

"Bruce Barnett" wrote in message
...


I'm new to metalworking and just got a Microlux 7x14.
I'm interested in machining thin disks - about 1 1/2" in diameter by
1/16".

I see that that some lathes have soft jaws, such as
http://www.taigtools.com/c1051.html

Is there an equivalent solution for the Sieg lathe?
Any other ideas?

I machined the back of the Taig 4-jaw to fit a mini-lathe (Craftex 7x10);
this is a common and easy thing to do.

I don't like the Taig chuck as much as I thought I would - the jaws have
only a projecting tang which engages a narrow part of the adjusting screw.
This lets them tip when you have the jaws almost at their outer limit; and
then it's easy to gouge the underside of the jaw-slots when moving them
inwards, leading to the jaws never again being square to the chuck. A set
of jaws with partial threads running on screws that are captive in the chuck
would less likely to do this, I think.

What I'd really like would be a 4-jaw independent chuck, about 4", with the
soft-jaw capability. The jaws on the Taig 4-jaw are HARD.

Is it possible to edm a hole with threads?

Is it possible to edm a hole with threads?



Yep, no problem.

I'm new to metalworking and just got a Microlux 7x14.
I'm interested in machining thin disks - about 1 1/2" in diameter by
1/16".


What are you trying to do to the disks? That's going to be a pretty
challenging project for a new guy.

wrote in message
oups.com...
Bruce,

I have 4-soft jaws on my Grizzly 7x12 (bascially same lathe as yours).

Get the Taig 4 Jaw 3 1/4" dia. self centering scroll chuck (steel body)
with aluminum soft jaws 3/4-16 thd. Then get the 3MT to 3/4-16 thread
adapter from LittleMachineShop.com. Then make your own draw bar from
threaded rod to hold the 3MT taper adapter in the spindle.


Yebbut...

I want _independent_ jaws...

Depends upon what you want to do with the disks. Facing off a disk merely
requires a chuck that will leave the disk proud of the jaws when the facing
is done. This is best doe with a collet type with a backing surface.
Edging is a bit more difficult and probably the best way is to use some
doublesided tape (not the foam stuff but rather the stuff that is using a
thin plastic center with adhesive on both sides) and a live center with
alarge pad rather than a point to hold the disk in place. The finished edge
needs to stand proud of the mountings.

--
Why do penguins walk so far to get to their nesting grounds?

According to Bruce Barnett :


I'm new to metalworking and just got a Microlux 7x14.
I'm interested in machining thin disks - about 1 1/2" in diameter by 1/16".

O.K. What is the spindle nose on that machine?

Looking at an on-line manual tells me that the chuck has three
studs, and you tighten nuts onto the studs to hold it to the spindle
flange. That may mean a special backplate will be needed, as I don't
find that in the list at the site below.

I see that that some lathes have soft jaws, such as
http://www.taigtools.com/c1051.html

Is there an equivalent solution for the Sieg lathe?
Any other ideas?

Here is one vendor of chucks some of which might fit your machine.

http://www.brassandtool.com/Chucks-Lathe.html

Your lathe's model number suggests that it has a 7" swing, which
would normally call for a 3.5" 3-jaw chuck. You could probably get away
with the 4" size, as long as you are careful to not extend the jaws too
far so they hit the ways.

It looks as though what will be the best for you is one of
these:

Bison Front Mount Self Centering Chuck

except that the smaller chucks, (3.25", 3.3" and 4") are not available
with the two-piece jaws. Even the 4.4" one is only available with solid
jaws, and the 5" is the smallest which is available with the two-piece
jaws.

There is another, which may work:

BISON Mini Three Jaw Self Centering Scroll Chuck

with the optional set of one-piece steel soft jaws:

Set of Soft Solid Jaws 7-882-214 $58.00

But -- those chucks are made to fit the Taig, Sherline, and
Unimat machines -- with a threaded spindle. Better, to start with the
Taig chuck, since it has the more useful pie-shaped jaws available, and
they are aluminum, and easier to machine to fit. To read my suggestions
about adapting that, skip to below the line of "+++++" below.

Here is where the backplates for the chucks are listed.

http://www.brassandtool.com/Backplate-Adaptors.html

If they have not yet added one to fit your lathe (which is a
fairly new one in the US, I believe), you will have to get something
like a:

Bison Semi-Machined Rough Opening Adapter

and first machine it to fit your lathe, and then machine the other side
to fit your choice of chuck.

++++++++++++++++++++++++++++++++++++++++++++++++++ ++++++++++++++++++++++

To adapt the Taig chuck, what you will need to do is to first
machine a piece of steel to fit your spindle nose, and fit it with the
proper studs (same metric thread as the ones on the existing chucks).

Then, mount it on the spindle, turn a portion of the length to
the OD for the thread used for the Taig and Sherline chucks (3/4-16
thread.) Make sure to leave a larger diameter to tighten the chuck back
against, and ideally, you should also leave a register diameter behind
the threads to match the register hole in the back of the chuck.

This won't be as strong as a normal 3-jaw chuck with two-piece
jaws, but it should be adequate for your project. And those pie-fan
jaws for the Taig lathe will probably be better for your task than any
soft top jaws available from Bison at present.

The main weak point on the Taig chuck is that you don't have a
key to tighten it. Instead, you have a "tommy bar" to stick in a hole
in the rotating scroll plate on the chuck, and to grip the chuck body
and jaws to keep it from rotating. (There really should be a hole in
the chuck body for a second tommy bar, but there is not one -- at least
on the rather old example which I have.

I hope that this is some help. Now I go to see what others have
answered.

Good Luck,
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 ---

Bruce Barnett wrote:

I'm new to metalworking and just got a Microlux 7x14.
I'm interested in machining thin disks - about 1 1/2" in diameter by 1/16".

I see that that some lathes have soft jaws, such as
http://www.taigtools.com/c1051.html

Is there an equivalent solution for the Sieg lathe?
Any other ideas?


Are you starting with a thin disk and machining the edge or face
OR
are you starting with a bar and want to part off thin disks?

Most of the good advice here has presumed the parting off. If you are
actually starting with thin disks you can stick them to a face plate
with double-stick tape or superglue. Hit superglued disks with hot air
or a gentle propane torch flame to release.

You can also fasten a disk of MDF to the faceplate as a sacrificial
layer if need be. Stick the disks to the MDF and have at it.
--
Fred R
"It doesn't really take all kinds; there just *are* all kinds".
Drop TROU to email.

(Nick Müller) writes:

Bruce Barnett wrote:

I'm interested in machining thin disks - about 1 1/2" in diameter by 1/16".

What machining operations do you intend to do?

Hollowing - for the most part, starting from the middle out.
So one disk will nest inside a second disk.

The second operation I'd like to do is to add a different metal around
the rim of an existing disk. I can see using two mushrooms for part of
the process.


--
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writes:

Bruce,

I have 4-soft jaws on my Grizzly 7x12 (bascially same lathe as yours).

Get the Taig 4 Jaw 3 1/4" dia. self centering scroll chuck (steel body)
with aluminum soft jaws 3/4-16 thd. Then get the 3MT to 3/4-16 thread
adapter from LittleMachineShop.com. Then make your own draw bar from
threaded rod to hold the 3MT taper adapter in the spindle.

Thanks!!

archiving this message and upping your score in my score file. You
are the second I've done this to. DoN was the first. You guys are great.

--
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"Bob May" writes:

Depends upon what you want to do with the disks. Facing off a disk merely
requires a chuck that will leave the disk proud of the jaws when the facing
is done. This is best doe with a collet type with a backing surface.

I looked at the collets, but I haven found one that will hold a 1 1/4" disk.

Edging is a bit more difficult and probably the best way is to use some
doublesided tape (not the foam stuff but rather the stuff that is using a
thin plastic center with adhesive on both sides) and a live center with
alarge pad rather than a point to hold the disk in place. The finished edge
needs to stand proud of the mountings.

Thanks. That's another keeper! (& Increase author's score).


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(DoN. Nichols) writes:

I hope that this is some help. Now I go to see what others have
answered.

Great info, DoN!!! Another keeper! Thanks!!!


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Fred R "spam writes:

Are you starting with a thin disk and machining the edge or face

Yup. In particular, I am using medallions with artistic designs -
think of it as a coin.

Most of the good advice here has presumed the parting off. If you are
actually starting with thin disks you can stick them to a face plate
with double-stick tape or superglue. Hit superglued disks with hot air
or a gentle propane torch flame to release.

Ah. Good to know, but the opposite side may not be 100% flat.
So superglue might not hold it well.

--
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$500 per message, and acknowledges the legality of this contract.

Bruce Barnett wrote:

I'm new to metalworking and just got a Microlux 7x14.
I'm interested in machining thin disks - about 1 1/2" in diameter by 1/16".

I see that that some lathes have soft jaws, such as
http://www.taigtools.com/c1051.html

Is there an equivalent solution for the Sieg lathe?
Any other ideas?


http://www.dunhamtool.com/step_chuck.html

Tom

Bruce Barnett wrote:

Hollowing - for the most part, starting from the middle out.
So one disk will nest inside a second disk.

I would suggest making a mandrel. Have some piece of round mild steel,
make a round recess on it's front where the disk fits into and glue it
in with LockTite. After the work, heat it up to about 150°C and the glue
will release.
Of course, you can use a magnetic chuck (with most steels) or a vacuum
chuck.


Nick
--
Motor Modelle // Engine Models
http://www.motor-manufaktur.de
DIY-DRO - YADRO - Eigenbau-Digitalanzeige

Tom writes:

Is there an equivalent solution for the Sieg lathe?
Any other ideas?


http://www.dunhamtool.com/step_chuck.html

Thanks! (Bookmarking THAT page.) Hmm. I don't see a price.



--
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According to :

DoN. Nichols wrote:
According to Bruce Barnett :

Lots snipped

His lathe(which is the same as mine) is supposed to be able to take a
5" chuck(with adaptor):

Note -- he was wanting to get a three-jaw chuck with soft jaws.
The general practice is to have the diameter of a three-jaw chuck half
the maximum swing over the bed.

This is because at some settings, the jaws (which are
*typically* not reversible) can extend out far enough to risk hitting
either the bed, or perhaps the arms of the carriage.

Four-jaw chucks typically can have each individual jaw reversed
at need to hold awkward shapes.

Three jaw chucks also have the additional mechanism of the
scroll plate and the gearing from the keys to the scroll plate, which
makes for a longer and a heavier chuck.

As an example, on my 12x24" Clausing, I'm happy with a 6"
(actually 6-1/4") three-jaw, but I use a 10" 4-jaw. And -- they are of
similar weights.

I was getting ready to purchase the following until this thread, now
I'd better wait and see.
http://www.littlemachineshop.com/pro...ProductID=2346

Note that is a 4-jaw chuck, not the three-jaw which he was
looking at. And soft jaws on a 4-jaw (with independent motion of each
jaw) don't really work out well.

Though I have no idea what how much of that chuck's capacity can be
used, I always thought that X inches meant that "X" was the largest
diameter the work piece could be.(That shows what I know).

"X" inches is the overall diameter of the chuck body. To that
must be added the extension of the jaws when they are adjusted to hold
larger workpieces.

Some (typically quite small) three-jaw chucks come with
reversible jaws.

More often, they come (or are at least available with) two sets
of jaws, one the normal set for gripping relatively small things on the
outside, and for gripping larger things on the inside. The second set
is the reverse, and is primarily for gripping larger things on the
outside, with a reduced length of grip.

The ones which can accept soft jaws are typically two-piece
jaws. A hardened set of master jaws which remain in the chuck, and sets
of jaws which bolt onto the masters. What typically comes with the
chuck is a hardened set of top jaws. Soft jaws are available to fit the
same master jaws. They can be either aluminum (really soft jaws), or a
mild steel (which is more common, except in the little 3-jaw chucks for
the Taig, which are non-standard in several other ways as well.

BTW I tried to answer an e-mail from you on the 21st, and my mail server
was unable to establish communications with your mail server. So, I did
not ignore the e-mail, your mail server does not like me for whatever
reason. Here are the headers:


================================================== ====================
Return-Path:
Delivered-To:
Received: (qmail 1921 invoked for bounce); 21 Feb 2006 19:41:51 -0000
Date: 21 Feb 2006 19:41:51 -0000
From:
To:
Subject: failure notice

Hi. This is the qmail-send program at d-and-d.com.
I'm afraid I wasn't able to deliver your message to the following addresses.
This is a permanent error; I've given up. Sorry it didn't work out.

:
Sorry, I wasn't able to establish an SMTP connection. (#4.4.1)
I'm not going to try again; this message has been in the queue too long.

--- Below this line is a copy of the message.

Return-Path:
Received: (qmail 28538 invoked by uid 100); 14 Feb 2006 18:14:49 -0000
Date: Tue, 14 Feb 2006 13:14:49 -0500
From: "DoN. Nichols"
To:
Subject: Tool Terms
Message-ID:

[ ... rest snipped because as usual it was large ... ]

================================================== ====================

It is the same e-mail address which you use in your newsgroup
headers. But I can't reach that system, even with a ping.

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 ---

According to Bruce Barnett :
(Nick Müller) writes:

Bruce Barnett wrote:

I'm interested in machining thin disks - about 1 1/2" in diameter by 1/16".

What machining operations do you intend to do?

Hollowing - for the most part, starting from the middle out.
So one disk will nest inside a second disk.

Hmm ... while the Taig pie-section soft jaws will work on this,
what I would think would be the best is a step collet, except that they
are rare on anything other than jeweler's lathes.

Or -- some soft collets with fairly large diameters -- but those
seem to be offered in 5C size mostly.

------------------------------ Pot Chuck Start ------------------------------

Or -- you could *make* a form of "pot chuck". Given the size of
your machine, I would suggest starting with a piece of brass or aluminum
somewhat larger in diameter than the larger of your workpiece diameter
and your spindle nose diameter. (They seem to be somewhat similar in
this case, though I'm not sure, not having seen your lathe.)

Anyway -- in a normal 3-jaw chuck, machine it to fit on the
spindle nose, and drill and tap it for the needed studs so you can mount
it directly on the spindle nose.

Mount it on the spindle nose, and mark it so you can always
replace it with the same stud in the same spindle flange hole.

Then, machine the ID a bit (say 1/8" to 1/4" smaller than the OD
of your workpiece, and perhaps 3/4" to 1-1/4" deep. Then machine a step
on the outer end just barely large enough and deep enough for a slip fit
of your workpiece.

Then, turn the OD down to perhaps 1/4" diameter greater than
your workpiece diameter, and down to the same depth that the inner bore
reaches.

Then, remove it from the spindle nose, and use a saw (a bandsaw
if you have it, otherwise a hacksaw or a slitting saw in a milling
machine.

Restore it to the spindle nose (being careful to use the same
stud per hole that you used when turning and boring it. Slip a
worm-geared hose clamp over the OD, place the workpiece into the ID, and
tighten the hose clamp to grip the workpiece.

Hmm ... you may want to drill a hole in the side of this to let
you reach the back of the workpiece to nudge it out if there is not
enough to grip.

Of course, you will have to make a different one for each size
of workpiece, but it should give you a very repeatable workpiece holding
system for this rather specialized task.

The pot chucks which I have seen in use were held in the 3-jaw
chuck, but that was on a much larger machine than you have.

------------------------------ Pot Chuck End ------------------------------

The second operation I'd like to do is to add a different metal around
the rim of an existing disk. I can see using two mushrooms for part of
the process.

I'm having a bit of trouble visualizing what you are describing
here -- especially the "mushrooms". If you intend to fit it to the
outside of something like a coin, without it extending beyond the
thickness of the coin, what I would suggest is another pot chuck for the
final OD of this, so you can bore the metal out to just too small to fit
(perhaps 0.001" too small, or a bit less.) When it is made, place the
coin (or coin equivalent) on a cold flat steel or cast iron piece, heat
the ring to an uncomfortable temperature (which temporarily expands it),
and drop it over the coin, using something like a piece of wood to hold
it down around the coin until the temperatures equalize and the ring
shrinks into a firm grip on the coin.

Good Luck,
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 ---

According to Bruce Barnett :
Tom writes:

Is there an equivalent solution for the Sieg lathe?
Any other ideas?


http://www.dunhamtool.com/step_chuck.html

Thanks! (Bookmarking THAT page.) Hmm. I don't see a price.

It looks as though they have online sales, but I can't get the
price information, even after adding one to the shopping cart. (Nor can
I see any other information about the item.) Perhaps it insists on only
talking to Microsoft's "Internet Explorer". :-)

There's another problem. It is designed to fit into 5C collets
or 16C collets -- with a bore of 1". I don't think that there is one of
that size available for your machine, as a 5C collet needs at least a
1-3/8" spindle through hole for the collet drawbar.

Good Luck,
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 ---

DoN. Nichols wrote:
According to :

DoN. Nichols wrote:
According to Bruce Barnett :

Lots snipped

His lathe(which is the same as mine) is supposed to be able to take a
5" chuck(with adaptor):

Note -- he was wanting to get a three-jaw chuck with soft jaws.
The general practice is to have the diameter of a three-jaw chuck half
the maximum swing over the bed.

I didn't know that. So then as I was beginning to think, one would not
be able to take full advantage of any chuck that was over 3-1/2".(I was
only using that 5" as an example of the size that the lathe would
take). Here's another 5", 3-Jaw they advertise as being compatible with
the lathe we have:
http://www.littlemachineshop.com/pro...ProductID=2345

This is because at some settings, the jaws (which are
*typically* not reversible) can extend out far enough to risk hitting
either the bed, or perhaps the arms of the carriage.

Four-jaw chucks typically can have each individual jaw reversed
at need to hold awkward shapes.

Three jaw chucks also have the additional mechanism of the
scroll plate and the gearing from the keys to the scroll plate, which
makes for a longer and a heavier chuck.

As an example, on my 12x24" Clausing, I'm happy with a 6"
(actually 6-1/4") three-jaw, but I use a 10" 4-jaw. And -- they are of
similar weights.

I was getting ready to purchase the following until this thread, now
I'd better wait and see.
http://www.littlemachineshop.com/pro...ProductID=2346

Note that is a 4-jaw chuck, not the three-jaw which he was
looking at. And soft jaws on a 4-jaw (with independent motion of each
jaw) don't really work out well.

Though I have no idea what how much of that chuck's capacity can be
used, I always thought that X inches meant that "X" was the largest
diameter the work piece could be.(That shows what I know).

"X" inches is the overall diameter of the chuck body. To that
must be added the extension of the jaws when they are adjusted to hold
larger workpieces.

This is just the sort of stuff you never read in catalogs. So I now
have to figure out what is the "largest" chuck that I could use on my
lathe to hold the "largest" work pieces.

Some (typically quite small) three-jaw chucks come with
reversible jaws.

More often, they come (or are at least available with) two sets
of jaws, one the normal set for gripping relatively small things on the
outside, and for gripping larger things on the inside. The second set
is the reverse, and is primarily for gripping larger things on the
outside, with a reduced length of grip.

The ones which can accept soft jaws are typically two-piece
jaws. A hardened set of master jaws which remain in the chuck, and sets
of jaws which bolt onto the masters. What typically comes with the
chuck is a hardened set of top jaws. Soft jaws are available to fit the
same master jaws. They can be either aluminum (really soft jaws), or a
mild steel (which is more common, except in the little 3-jaw chucks for
the Taig, which are non-standard in several other ways as well.

I guess machining a new set of jaws out of Aluminum is not plausible.
:-)

What I'd do is make a hard wooden holder with a hole that would be the
same diameter as that of the disks, and the appropriate depth(and a
small hole all the way through the center so that glue will dry when
used along with a press fit of the disks into the holder. The holder
would then go into the normal chuck.

Or perhaps brush some liquid insulation around the perimeter of the
disks and let dry. The kind used on electrical wires. It peels off
easily.

BTW I tried to answer an e-mail from you on the 21st, and my mail server
was unable to establish communications with your mail server. So, I did
not ignore the e-mail, your mail server does not like me for whatever
reason. Here are the headers:


================================================== ====================
Return-Path:
Delivered-To:
Received: (qmail 1921 invoked for bounce); 21 Feb 2006 19:41:51 -0000
Date: 21 Feb 2006 19:41:51 -0000
From:
To:
Subject: failure notice

Hi. This is the qmail-send program at d-and-d.com.
I'm afraid I wasn't able to deliver your message to the following addresses.
This is a permanent error; I've given up. Sorry it didn't work out.

:
Sorry, I wasn't able to establish an SMTP connection. (#4.4.1)
I'm not going to try again; this message has been in the queue too long.

--- Below this line is a copy of the message.

Return-Path:
Received: (qmail 28538 invoked by uid 100); 14 Feb 2006 18:14:49 -0000
Date: Tue, 14 Feb 2006 13:14:49 -0500
From: "DoN. Nichols"
To:
Subject: Tool Terms
Message-ID:

[ ... rest snipped because as usual it was large ... ]

================================================== ====================

It is the same e-mail address which you use in your newsgroup
headers. But I can't reach that system, even with a ping.

That's odd.

Actually, Verizon internet service is crap, so I guess it's not odd.

When I have these kind of problems with Verizon, I use my hotmail
address which is the same as my name, except backwards(Harrisdarren).

Darren Harris
Staten Island, New York.

According to :

DoN. Nichols wrote:

[ ... ]

Note -- he was wanting to get a three-jaw chuck with soft jaws.
The general practice is to have the diameter of a three-jaw chuck half
the maximum swing over the bed.

I didn't know that. So then as I was beginning to think, one would not
be able to take full advantage of any chuck that was over 3-1/2".(I was
only using that 5" as an example of the size that the lathe would
take). Here's another 5", 3-Jaw they advertise as being compatible with
the lathe we have:
http://www.littlemachineshop.com/pro...ProductID=2345

One can use larger chucks, but the added weight hastens wear on
the bearings.

And you have to be careful that the extended jaws do not hit the
ways, or the side arms of the carriage, if your carriage has them.
IIRC, it does not.

Note that photo on that web page includes the second set of
reverse jaws for gripping larger workpieces. But, because of the steps,
they can't grip a great length, so you need support (steady rest) once
the length of the workpiece exceeds a certain percentage of the step
length.

[ ... ]

"X" inches is the overall diameter of the chuck body. To that
must be added the extension of the jaws when they are adjusted to hold
larger workpieces.

This is just the sort of stuff you never read in catalogs. So I now
have to figure out what is the "largest" chuck that I could use on my
lathe to hold the "largest" work pieces.

Part of that is a function of how long the workpieces are. And,
whether you have a steady rest to help support the workpiece.

[ ... ]

The ones which can accept soft jaws are typically two-piece
jaws. A hardened set of master jaws which remain in the chuck, and sets
of jaws which bolt onto the masters. What typically comes with the
chuck is a hardened set of top jaws. Soft jaws are available to fit the
same master jaws. They can be either aluminum (really soft jaws), or a
mild steel (which is more common, except in the little 3-jaw chucks for
the Taig, which are non-standard in several other ways as well.

I guess machining a new set of jaws out of Aluminum is not plausible.
:-)

Why not? Where do you think the jaws come from? Actually, the
Taig soft jaws are easier to make than most, because there is not the
middle step to give precise location which is present on most master
jaws. All the Taig jaws have to offer are the screws which hold them
on.

Note that the "Pie" jaws are actually made from electronics
heat-sink extrusion, which is why all the fingers.

Now -- This applies only to the top jaws to go onto existing
master jaws. For making complete jaws from scratch, you need to
consider how you are going to make the scroll teeth on the bottoms of
the jaws. Each of the three jaws has the teeth at a different offset,
so the three jaws wind up close to center when the chuck is assembled.

What I'd do is make a hard wooden holder with a hole that would be the
same diameter as that of the disks, and the appropriate depth(and a
small hole all the way through the center so that glue will dry when
used along with a press fit of the disks into the holder. The holder
would then go into the normal chuck.

Note that wood, even hardwood, changes dimensions with the
ambient humidity. You can't keep any kind of precision with wood.

Or perhaps brush some liquid insulation around the perimeter of the
disks and let dry. The kind used on electrical wires. It peels off
easily.

I doubt that it would hold very well, but you are welcome to
try, and report back on the results.

BTW I tried to answer an e-mail from you on the 21st, and my mail server
was unable to establish communications with your mail server. So, I did
not ignore the e-mail, your mail server does not like me for whatever
reason. Here are the headers:

[ ... ]

:
Sorry, I wasn't able to establish an SMTP connection. (#4.4.1)
I'm not going to try again; this message has been in the queue too long.

[ ... ]

That's odd.

Actually, Verizon internet service is crap, so I guess it's not odd.

When I have these kind of problems with Verizon, I use my hotmail
address which is the same as my name, except backwards(Harrisdarren).

It does not seem to belong to Verizon. The IP address which is
returned from an nslookup of "mail.con2.com" is 204.251.15.174, and a
reverse lookup on that yields:

OrgName: Zipa, LLC
OrgID: ZIPAL
Address: 650 Poydras Street
Address: Suite 1015
City: New Orleans
StateProv: LA
PostalCode: 70130
Country: US

And that is two layers down from Sprint as the top level owner of the
netblock.

Unless someone has been playing games with the DNS, this is quite
strange.

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 ---

According to :

DoN. Nichols wrote:

[ ... ]

Unless someone has been playing games with the DNS, this is quite
strange.

That's the problem!

When you said that you tried to answer an e-mail from me, I thought
that you were using the send to respond to the last e-mail I wrote you.

I was!

is the now defunct Staten Island ISP that I
originally signed up with Deja.com - Google Groups.

But -- it is still in your headers -- both in the newsgroups (to
this moment), and in the e-mail which you last sent me -- which appears
to have been sent by you as e-mail in reply to a posting in the newsgroup.

Obviously this time you weren't trying to respond directly to the
e-mail I sent from. But instead via the newsgroups.

I don't *send* e-mail responses to newsgroup postings -- unless
I feel that someone is about to damage some equipment, and want to reach
them as quickly as possible.

I *can't* even send e-mail from the machine which I use for
Newsreading, so I have to jump through hoops to send an e-mail response,
mostly cut-and-paste to another machine.

I was trying to respond to an e-mail which I received -- though
*you* may have sent it from your newsreader, not your e-mail client.

Note the quoted headers (somewhat trimmed -- snips marked) from
your e-mail:

================================================== ====================
From Tue Feb 14 00:37:40 2006
Return-Path:

[ ... ]

Received: from mproxy.googlegroups.com (216.239.56.131)
by cadeau.d-and-d.com with SMTP; 14 Feb 2006 05:37:40 -0000

[ ... ]

From:
To: "DoN. Nichols"
Subject: Tool Terms
Date: Mon, 13 Feb 2006 21:37:28 -0800

[ ... ]

X-HTTP-UserAgent: Mozilla/4.0 (compatible; MSIE 6.0; Windows 98; Win 9x 4.90; (R1 1.3);
+.NET CLR 1.1.4322),gzip(gfe),gzip(gfe)
================================================== ====================

I note that you are using google to read newsgroups, and perhaps
that confused your attempt to post to the newsgroup and turned it into
an e-mail reply instead.

The e-mail you wanted to respond to is


It was not in the headers.

(There was/is no way to change things, but at least I'm not getting all
the spam that probably goes to the original e-mail I had).

There is that.

I'll put the new address onto the bounced e-mail, though we have
moved way past that by now, I think.

*Please* don't send e-mail responses to newsgroup postings. I
prefer to keep those in the newsgroup.

Thanks,
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 ---

DoN. Nichols wrote:
According to :

DoN. Nichols wrote:

[ ... ]

Note -- he was wanting to get a three-jaw chuck with soft jaws.
The general practice is to have the diameter of a three-jaw chuck half
the maximum swing over the bed.

I didn't know that. So then as I was beginning to think, one would not
be able to take full advantage of any chuck that was over 3-1/2".(I was
only using that 5" as an example of the size that the lathe would
take). Here's another 5", 3-Jaw they advertise as being compatible with
the lathe we have:
http://www.littlemachineshop.com/pro...ProductID=2345

One can use larger chucks, but the added weight hastens wear on
the bearings.

And you have to be careful that the extended jaws do not hit the
ways, or the side arms of the carriage, if your carriage has them.
IIRC, it does not.

Note that photo on that web page includes the second set of
reverse jaws for gripping larger workpieces. But, because of the steps,
they can't grip a great length, so you need support (steady rest) once
the length of the workpiece exceeds a certain percentage of the step
length.

[ ... ]

"X" inches is the overall diameter of the chuck body. To that
must be added the extension of the jaws when they are adjusted to hold
larger workpieces.

This is just the sort of stuff you never read in catalogs. So I now
have to figure out what is the "largest" chuck that I could use on my
lathe to hold the "largest" work pieces.

Part of that is a function of how long the workpieces are. And,
whether you have a steady rest to help support the workpiece.

I'm thinking more in terms of diameter.(Flat stock).

The ones which can accept soft jaws are typically two-piece
jaws. A hardened set of master jaws which remain in the chuck, and sets
of jaws which bolt onto the masters. What typically comes with the
chuck is a hardened set of top jaws. Soft jaws are available to fit the
same master jaws. They can be either aluminum (really soft jaws), or a
mild steel (which is more common, except in the little 3-jaw chucks for
the Taig, which are non-standard in several other ways as well.

I guess machining a new set of jaws out of Aluminum is not plausible.
:-)

Why not? Where do you think the jaws come from? Actually, the
Taig soft jaws are easier to make than most, because there is not the
middle step to give precise location which is present on most master
jaws. All the Taig jaws have to offer are the screws which hold them
on.

What I meant was that I don't think he has the equipment for machining
the jaws himself.

Note that the "Pie" jaws are actually made from electronics
heat-sink extrusion, which is why all the fingers.

Now -- This applies only to the top jaws to go onto existing
master jaws. For making complete jaws from scratch, you need to
consider how you are going to make the scroll teeth on the bottoms of
the jaws. Each of the three jaws has the teeth at a different offset,
so the three jaws wind up close to center when the chuck is assembled.

Sounds like a CNC job to me. Or a job for an experienced machinist.

What I'd do is make a hard wooden holder with a hole that would be the
same diameter as that of the disks, and the appropriate depth(and a
small hole all the way through the center so that glue will dry when
used along with a press fit of the disks into the holder. The holder
would then go into the normal chuck.

Note that wood, even hardwood, changes dimensions with the
ambient humidity. You can't keep any kind of precision with wood.

It shouldn't be too extreme. Especially since the work is not big and
heavy. And a facing operation will not pull it out of the holder. But
one can use glue if a small hole is place in the center for ventilation
so the glue will dry.

But if it is still an issue then an option is Delrin which doesn't soak
up moisture and has excellent dimensional stability.

Or perhaps brush some liquid insulation around the perimeter of the
disks and let dry. The kind used on electrical wires. It peels off
easily.

I doubt that it would hold very well, but you are welcome to
try, and report back on the results.

It's job would be to just keep the jaws from damaging the workpiece.

Darren Harris
Staten Island, New York.

According to :

First off -- I got two e-mails from you today -- with the old
return address which your usenet articles show. I am not going to
bother typing answers to them, only to have the answers sit for a week
and then pop back up as undeliverable.

*If* you posted as well as e-mailed, I'll try to answer here in
the newsgroup. If you didn't -- then take this as a reason to not send
me e-mail copies of usenet postings, or e-mail with bogus return
addresses.

DoN. Nichols wrote:

[ ... ]

One can use larger chucks, but the added weight hastens wear on
the bearings.

And you have to be careful that the extended jaws do not hit the
ways, or the side arms of the carriage, if your carriage has them.
IIRC, it does not.

Note that photo on that web page includes the second set of
reverse jaws for gripping larger workpieces. But, because of the steps,
they can't grip a great length, so you need support (steady rest) once
the length of the workpiece exceeds a certain percentage of the step
length.

[ ... ]

"X" inches is the overall diameter of the chuck body. To that
must be added the extension of the jaws when they are adjusted to hold
larger workpieces.

This is just the sort of stuff you never read in catalogs. So I now
have to figure out what is the "largest" chuck that I could use on my
lathe to hold the "largest" work pieces.

Part of that is a function of how long the workpieces are. And,
whether you have a steady rest to help support the workpiece.

I'm thinking more in terms of diameter.(Flat stock).

O.K. For that, it should suffice. Obviously a 4-jaw
independent is what is needed.

The ones which can accept soft jaws are typically two-piece
jaws. A hardened set of master jaws which remain in the chuck, and sets
of jaws which bolt onto the masters. What typically comes with the
chuck is a hardened set of top jaws. Soft jaws are available to fit the
same master jaws. They can be either aluminum (really soft jaws), or a
mild steel (which is more common, except in the little 3-jaw chucks for
the Taig, which are non-standard in several other ways as well.

I guess machining a new set of jaws out of Aluminum is not plausible.
:-)

Why not? Where do you think the jaws come from? Actually, the
Taig soft jaws are easier to make than most, because there is not the
middle step to give precise location which is present on most master
jaws. All the Taig jaws have to offer are the screws which hold them
on.

What I meant was that I don't think he has the equipment for machining
the jaws himself.

"He"? Who else came into this thread?

If you have milling attachments for the lathe, you can make soft
jaws -- especially the ones for the Taig with its simple mount.

Note that the "Pie" jaws are actually made from electronics
heat-sink extrusion, which is why all the fingers.

Now -- This applies only to the top jaws to go onto existing
master jaws. For making complete jaws from scratch, you need to
consider how you are going to make the scroll teeth on the bottoms of
the jaws. Each of the three jaws has the teeth at a different offset,
so the three jaws wind up close to center when the chuck is assembled.

Sounds like a CNC job to me. Or a job for an experienced machinist.

It used to be done with the jaw blanks mounted on a fixture on
an index head which was geared to the X-axis leadscrew on a milling
machine. The index head would turn fairly slowly (from a power feed),
and the gears would turn the leadscrew to provide the proper feed per
turn. A small endmill would cut the spiral threads in the back of the
jaws. (Quite probably, the fixture would hold two sets of jaws at once
to improve production and to minimize the amount of time spent cutting
air.) A similar setup would machine the scroll plate for inside the
jaws. The jaws would be shaped, and hardened, and then the two sets of
scroll teeth would be lapped -- either together, or on separate
fixtures. This would shape the teeth to allow handling the varying
radius as the jaws close or open.

Yes -- it could be one with CNC now -- but it may be more
economical to use the old machines if they still work well.

What I'd do is make a hard wooden holder with a hole that would be the
same diameter as that of the disks, and the appropriate depth(and a
small hole all the way through the center so that glue will dry when
used along with a press fit of the disks into the holder. The holder
would then go into the normal chuck.

Note that wood, even hardwood, changes dimensions with the
ambient humidity. You can't keep any kind of precision with wood.

It shouldn't be too extreme.

A friend made a copy of an old instrument called a
"hudry-gurdy". Not the barrel organs, but rather a stringed instrument
in which the strings were bowed by the rim of a wooden wheel. Well, the
problem was that as the wood dried out, what had started with a nice
round wheel shrunk differently along the grain and across it, so it was
pressing harder on the strings during part of its rotation than during
other parts. It could not be kept in a shape good enough to produce a
steady sound.

I finally machined one for him from plexiglass, which would not
shrink. The only problem was that I put too good a polish on the rim,
and it would not hold rosin to drive the strings. :-) He solved that
with a strip of wood veneer with a diagonal join.

So -- yes, wood *does* shrink enough to be a problem as it
dries. The original ones were almost certainly made with wood which had
been dried for decades before being shaped put to use, not modern
kiln-dried wood.

Especially since the work is not big and
heavy. And a facing operation will not pull it out of the holder. But
one can use glue if a small hole is place in the center for ventilation
so the glue will dry.

But if it is still an issue then an option is Delrin which doesn't soak
up moisture and has excellent dimensional stability.

Delrin, a set of radial grooves from the center hole to near the
outside diameter, and a vacuum pump sucking on the center hole to keep
the workpiece in place.

But probably not for stainless steel. :-)

Or perhaps brush some liquid insulation around the perimeter of the
disks and let dry. The kind used on electrical wires. It peels off
easily.

I doubt that it would hold very well, but you are welcome to
try, and report back on the results.

It's job would be to just keep the jaws from damaging the workpiece.

Oh -- that is what aluminum soft jaws are for. When they are
machined in place in the chuck (in the lathe) the shape is such that
they will match the curve of the OD of the workpiece, so there is no
sharp edge trying to indent the workpiece.

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 ---

I don't even bother with people that post to me privately when the post is a
usenet posting that they are responding to. As far as I am concerned, those
idiots are just arogant itiots with a bit of paranoia and need to be
ignored.
If I posted something on the usenet, I expect replies on the usenet.
I bet the guy is still getting a bunch of spam even tho he's munged his
email addres anyway.

--
Why do penguins walk so far to get to their nesting grounds?

First off -- I got two e-mails from you today -- with the old
return address which your usenet articles show. I am not going to
bother typing answers to them, only to have the answers sit for a week
and then pop back up as undeliverable.

*If* you posted as well as e-mailed, I'll try to answer here in
the newsgroup. If you didn't -- then take this as a reason to not send
me e-mail copies of usenet postings, or e-mail with bogus return
addresses.

I wouldn't intentionally respond with a direct e-mail to a newsgroup
post. My home pc went down last week and I was posting from the
library, so that may have been the problem.

I guess machining a new set of jaws out of Aluminum is not plausible.
:-)

Why not? Where do you think the jaws come from? Actually, the
Taig soft jaws are easier to make than most, because there is not the
middle step to give precise location which is present on most master
jaws. All the Taig jaws have to offer are the screws which hold them
on.

What I meant was that I don't think he has the equipment for machining
the jaws himself.

"He"? Who else came into this thread?

I was referring to the original poster.

If you have milling attachments for the lathe, you can make soft
jaws -- especially the ones for the Taig with its simple mount.

Ok. Those "teeth" seem difficult to me. I thought they were courved,
and that tolerance was very critical.

Note that the "Pie" jaws are actually made from electronics
heat-sink extrusion, which is why all the fingers.

Now -- This applies only to the top jaws to go onto existing
master jaws. For making complete jaws from scratch, you need to
consider how you are going to make the scroll teeth on the bottoms of
the jaws. Each of the three jaws has the teeth at a different offset,
so the three jaws wind up close to center when the chuck is assembled.

Sounds like a CNC job to me. Or a job for an experienced machinist.

It used to be done with the jaw blanks mounted on a fixture on
an index head which was geared to the X-axis leadscrew on a milling
machine. The index head would turn fairly slowly (from a power feed),
and the gears would turn the leadscrew to provide the proper feed per
turn. A small endmill would cut the spiral threads in the back of the
jaws. (Quite probably, the fixture would hold two sets of jaws at once
to improve production and to minimize the amount of time spent cutting
air.) A similar setup would machine the scroll plate for inside the
jaws. The jaws would be shaped, and hardened, and then the two sets of
scroll teeth would be lapped -- either together, or on separate
fixtures. This would shape the teeth to allow handling the varying
radius as the jaws close or open.

Yes -- it could be one with CNC now -- but it may be more
economical to use the old machines if they still work well.

But I assume that you don't recommend using a lathe for this, correct?

What I'd do is make a hard wooden holder with a hole that would be the
same diameter as that of the disks, and the appropriate depth(and a
small hole all the way through the center so that glue will dry when
used along with a press fit of the disks into the holder. The holder
would then go into the normal chuck.

Note that wood, even hardwood, changes dimensions with the
ambient humidity. You can't keep any kind of precision with wood.

It shouldn't be too extreme.

A friend made a copy of an old instrument called a
"hudry-gurdy". Not the barrel organs, but rather a stringed instrument
in which the strings were bowed by the rim of a wooden wheel. Well, the
problem was that as the wood dried out, what had started with a nice
round wheel shrunk differently along the grain and across it, so it was
pressing harder on the strings during part of its rotation than during
other parts. It could not be kept in a shape good enough to produce a
steady sound.

I finally machined one for him from plexiglass, which would not
shrink. The only problem was that I put too good a polish on the rim,
and it would not hold rosin to drive the strings. :-) He solved that
with a strip of wood veneer with a diagonal join.

So -- yes, wood *does* shrink enough to be a problem as it
dries. The original ones were almost certainly made with wood which had
been dried for decades before being shaped put to use, not modern
kiln-dried wood.

Solution: Keep a spray bottom filled with water handy. :-)

Especially since the work is not big and
heavy. And a facing operation will not pull it out of the holder. But
one can use glue if a small hole is place in the center for ventilation
so the glue will dry.

But if it is still an issue then an option is Delrin which doesn't soak
up moisture and has excellent dimensional stability.

Delrin, a set of radial grooves from the center hole to near the
outside diameter, and a vacuum pump sucking on the center hole to keep
the workpiece in place.

But probably not for stainless steel. :-)

Sounds like a complicated set-up for such a "simple" project.

Or perhaps brush some liquid insulation around the perimeter of the
disks and let dry. The kind used on electrical wires. It peels off
easily.

I doubt that it would hold very well, but you are welcome to
try, and report back on the results.

It's job would be to just keep the jaws from damaging the workpiece.

Oh -- that is what aluminum soft jaws are for. When they are
machined in place in the chuck (in the lathe) the shape is such that
they will match the curve of the OD of the workpiece, so there is no
sharp edge trying to indent the workpiece.

That's if he had or could find aluminum jaws. :-)

Darren Harris
Staten Island, New York.

According to :
First off -- I got two e-mails from you today -- with the old
return address which your usenet articles show. I am not going to
bother typing answers to them, only to have the answers sit for a week
and then pop back up as undeliverable.

*If* you posted as well as e-mailed, I'll try to answer here in
the newsgroup. If you didn't -- then take this as a reason to not send
me e-mail copies of usenet postings, or e-mail with bogus return
addresses.

I wouldn't intentionally respond with a direct e-mail to a newsgroup
post. My home pc went down last week and I was posting from the
library, so that may have been the problem.

Yep. I found the articles, and posted a followup to one of the
two.

I guess machining a new set of jaws out of Aluminum is not plausible.
:-)

Why not? Where do you think the jaws come from? Actually, the
Taig soft jaws are easier to make than most, because there is not the
middle step to give precise location which is present on most master
jaws. All the Taig jaws have to offer are the screws which hold them
on.

What I meant was that I don't think he has the equipment for machining
the jaws himself.

"He"? Who else came into this thread?

I was referring to the original poster.

If you have milling attachments for the lathe, you can make soft
jaws -- especially the ones for the Taig with its simple mount.

Ok. Those "teeth" seem difficult to me. I thought they were courved,
and that tolerance was very critical.


O.K. You're talking about machining entire jaws from scratch,
while I was talking about machining new "top" jaws to bolt onto a
master jaw which remains in the chuck body. Quite a different task.

The chucks designed for this (such as my Bison 3-jaw) have a
hardened "master" jaw in the body of the chuck, almost flush with the
top of the chuck surface. They also come with a hardened set of top
jaws for normal lathe use, except that if you need outside gripping
jaws, you can unbolt and reverse the top jaws without having to remove
the master jaws and replace them, as you have to do with normal
one-piece jaws. There are also available from the maker or others sets
of mild steel soft jaws, which start out with no steps at all -- full
height all the way along the length. This, you bolt to the chuck's
master jaws, and then (after blocking the jaws in place with something
appropriate), you turn them in the lathe and chuck to make a set of jaws
precisely designed to hold your workpiece -- for any project where you
are going to need to make a lot of the same thing. These can be the
right diameter to hold the workpiece precisely (more accurately than
with the standard jaws), and can be bored with a step to ensure that
each workpiece is installed to the proper depth without having to
measure each time.

Normally, such a set of soft jaws is set aside with the other
special tooling for a project, and returned to the chuck when you have
to make that again.

However, if you don't expect any more of those, you set the soft
jaws aside until you have another project which can benefit from soft
jaws, and re-bore the jaws to fit the new (obviously somewhat larger)
job. Usually, they can go through several re-borings before there is
not enough metal left to re-bore them again.

Normal two-piece jaws have a longitudinal groove on the
under surface which matches a raised rib on the master jaw, and a
cross-groove across the middle of the top jaw which mates with a raised
rib across the master, thus giving accurate location in both directions
when replacing a soft jaw on its master jaw. (You should always mark
the soft jaws so you can restore them to the same master jaw each time,
or you lose a bit of the accuracy which is otherwise possible.

The 3-jaw chuck for the Taig has only the longitudinal groove,
with the radial location being done by the bodies of the screws which
attach the top jaws to the master jaws, so they are not quite as
precisely repeatable. But they also come only with aluminum soft jaws,
not with mild steel which is common with others.

In any case, it is easy enough to mill the underside of the
stock to make jaws and drill and counterbore the holes for the screws
which attach the top jaws to the master jaws.

Making entire one-piece chuck jaws, however, is a much more
difficult task, and not what I was referring to.

Note that the "Pie" jaws are actually made from electronics
heat-sink extrusion, which is why all the fingers.

Now -- This applies only to the top jaws to go onto existing
master jaws. For making complete jaws from scratch, you need to
consider how you are going to make the scroll teeth on the bottoms of
the jaws. Each of the three jaws has the teeth at a different offset,
so the three jaws wind up close to center when the chuck is assembled.

Sounds like a CNC job to me. Or a job for an experienced machinist.

It used to be done with the jaw blanks mounted on a fixture on
an index head which was geared to the X-axis leadscrew on a milling
machine. The index head would turn fairly slowly (from a power feed),
and the gears would turn the leadscrew to provide the proper feed per
turn. A small endmill would cut the spiral threads in the back of the
jaws. (Quite probably, the fixture would hold two sets of jaws at once
to improve production and to minimize the amount of time spent cutting
air.) A similar setup would machine the scroll plate for inside the
jaws. The jaws would be shaped, and hardened, and then the two sets of
scroll teeth would be lapped -- either together, or on separate
fixtures. This would shape the teeth to allow handling the varying
radius as the jaws close or open.

Yes -- it could be one with CNC now -- but it may be more
economical to use the old machines if they still work well.

But I assume that you don't recommend using a lathe for this, correct?

I do not. The problems, as I see them, a

1) The speed of the spindle is too fast to be practical, unless
the spindle is hand cranked.

2) The coupling from the spindle to the cross-feed is not
repeatable to make the cut in multiple passes. There is no
provision for something like the half-nuts used for normal
linear threads.

3) The task really calls for a rotating tool like a small end
mill, and an appropriate tool to drive it.

[ ... ]

Note that wood, even hardwood, changes dimensions with the
ambient humidity. You can't keep any kind of precision with wood.

It shouldn't be too extreme.

A friend made a copy of an old instrument called a
"hudry-gurdy". Not the barrel organs, but rather a stringed instrument
in which the strings were bowed by the rim of a wooden wheel. Well, the
problem was that as the wood dried out, what had started with a nice
round wheel shrunk differently along the grain and across it, so it was
pressing harder on the strings during part of its rotation than during
other parts. It could not be kept in a shape good enough to produce a
steady sound.

I finally machined one for him from plexiglass, which would not
shrink. The only problem was that I put too good a polish on the rim,
and it would not hold rosin to drive the strings. :-) He solved that
with a strip of wood veneer with a diagonal join.

So -- yes, wood *does* shrink enough to be a problem as it
dries. The original ones were almost certainly made with wood which had
been dried for decades before being shaped put to use, not modern
kiln-dried wood.

Solution: Keep a spray bottom filled with water handy. :-)

Hardly. The majority of the instrument was made of wood, glued
together.

Especially since the work is not big and
heavy. And a facing operation will not pull it out of the holder. But
one can use glue if a small hole is place in the center for ventilation
so the glue will dry.

But if it is still an issue then an option is Delrin which doesn't soak
up moisture and has excellent dimensional stability.

Delrin, a set of radial grooves from the center hole to near the
outside diameter, and a vacuum pump sucking on the center hole to keep
the workpiece in place.

But probably not for stainless steel. :-)

Sounds like a complicated set-up for such a "simple" project.

Sometimes, that is the best way to go.

Or perhaps brush some liquid insulation around the perimeter of the
disks and let dry. The kind used on electrical wires. It peels off
easily.

I doubt that it would hold very well, but you are welcome to
try, and report back on the results.

It's job would be to just keep the jaws from damaging the workpiece.

Oh -- that is what aluminum soft jaws are for. When they are
machined in place in the chuck (in the lathe) the shape is such that
they will match the curve of the OD of the workpiece, so there is no
sharp edge trying to indent the workpiece.

That's if he had or could find aluminum jaws. :-)

As long as your chuck has two-piece jaws, you can make more
aluminum (or steel) jaws with a milling machine.

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 ---

-snip-

Making entire one-piece chuck jaws, however, is a much more
difficult task, and not what I was referring to.

Ok. I plan to tak e a look inside my chuck/s. I've not seen much of the
insides outside of some pics that weren't too detailed.

-snip-

Note that wood, even hardwood, changes dimensions with the
ambient humidity. You can't keep any kind of precision with wood.

It shouldn't be too extreme.

A friend made a copy of an old instrument called a
"hudry-gurdy". Not the barrel organs, but rather a stringed instrument
in which the strings were bowed by the rim of a wooden wheel. Well, the
problem was that as the wood dried out, what had started with a nice
round wheel shrunk differently along the grain and across it, so it was
pressing harder on the strings during part of its rotation than during
other parts. It could not be kept in a shape good enough to produce a
steady sound.

I finally machined one for him from plexiglass, which would not
shrink. The only problem was that I put too good a polish on the rim,
and it would not hold rosin to drive the strings. :-) He solved that
with a strip of wood veneer with a diagonal join.

So -- yes, wood *does* shrink enough to be a problem as it
dries. The original ones were almost certainly made with wood which had
been dried for decades before being shaped put to use, not modern
kiln-dried wood.

Solution: Keep a spray bottom filled with water handy. :-)

Hardly. The majority of the instrument was made of wood, glued
together.

Actually, I was referring to the "disk holder" that were were talking
about.

-snip-

Or perhaps brush some liquid insulation around the perimeter of the
disks and let dry. The kind used on electrical wires. It peels off
easily.

I doubt that it would hold very well, but you are welcome to
try, and report back on the results.

It's job would be to just keep the jaws from damaging the workpiece.

Oh -- that is what aluminum soft jaws are for. When they are
machined in place in the chuck (in the lathe) the shape is such that
they will match the curve of the OD of the workpiece, so there is no
sharp edge trying to indent the workpiece.

That's if he had or could find aluminum jaws. :-)

As long as your chuck has two-piece jaws, you can make more
aluminum (or steel) jaws with a milling machine.

That good to know. I was aware that the chucks jaws were made the way
you described.

Thanks.

Darren Harris
Staten Island, New York.