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PM 1440 - First Failure
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Bob La Londe
Nov 28, 2016, 12:34:15 PM11/28/16
to
Well, I just had my first failure with my PM 1440. The cam-lock on the
tailstock broke. This lathe has been just so amazing compared to my other
Chinese lathes that I got my feelings hurt. LOL.
It wasn't a particulary hard fix. I had to pull and split the tailstock to
remove the shaft, cam, and pull block. I found the cam was held to the
shaft with a spring pin (or roll pin if you prefer). It had broken. I know
why it had broken. Spring pins are strong, but not as strong as you might
think. When ever I do some heavier drilling (like clear a hole with a 1"
drill bit) I tend to bump the handle firmly with my hand. That cumulative
force surely is what caused the pin to break.
The other issues is the pin is in my opinion a little short for the job. I
think its a standard length pin though as I had several the same length in a
box of assorted spring pins I bought a while back for emergencies. I think
as a result the shorter than full depth engagement in the cam allows it to
flex more when I bump the handle. Since I had a pin and I was in the middle
of a project I put it back together and dialed the tailstock back in. I may
find it hard to break the habit of bumping the handle so eventually I am
sure it will fail again. When it does I would like to be ready with a
better solution. My first thought was to use a solid stainless dowel cut to
length. Throw some Loctite on it and call it a day. Drilling and reaming
for a nice light interferrence fit might be tedious, but its within my
capability. Just a few tenths so it stays in place, but can be driven out
easily enough. If the fit is to both parts, the cam and the shaft, there
shouldn't be any slop to allow the pin to cause wear. Are there any
issues with that? The other thought I had was to make a new cam that has to
be pressed onto the shaft eliminating another other possible play/wear
issue. A one piece shaft and cam is not a practical solution. I'd have to
drill out the side of the tail stock and the insert a bushing to support the
shaft. Not impossible, but a lot of unnecessary work and seriously
overkill. On the other hand it would probably outlast me. LOL.
This brings us to failure number two. After I put it back together I threw
a piece of stock in the chuck and turned a point to align the tailstock to.
Then I threw a dead center in the tail stock and started lining up the
points. When I got out my loupe I found the center was blunt. Looked like
maybe it was dropped. I couldn't see it with just my glasses on, but it was
clear to see with the loupe. Thinking maybe I dropped it and didn't
remember I got one out of the tool cart that had never been used before. It
was also blunt. It was a nice tiny dome, but it was blunt. Orders of
magnitude bigger than the tip on my turned point. Atleast it seemed uniform
so I dialed it in as best I could. I realize even with hardened and ground
steel handling is coming to take off needle tips from an object that heavy,
so maybe that's the norm. I don't know. Both centers came with the lathe so
perhaps they are just lower grade Chinese parts. Do all dead centers have a
domed tip when looked at under a glass?
tailstock broke. This lathe has been just so amazing compared to my other
Chinese lathes that I got my feelings hurt. LOL.
It wasn't a particulary hard fix. I had to pull and split the tailstock to
remove the shaft, cam, and pull block. I found the cam was held to the
shaft with a spring pin (or roll pin if you prefer). It had broken. I know
why it had broken. Spring pins are strong, but not as strong as you might
think. When ever I do some heavier drilling (like clear a hole with a 1"
drill bit) I tend to bump the handle firmly with my hand. That cumulative
force surely is what caused the pin to break.
The other issues is the pin is in my opinion a little short for the job. I
think its a standard length pin though as I had several the same length in a
box of assorted spring pins I bought a while back for emergencies. I think
as a result the shorter than full depth engagement in the cam allows it to
flex more when I bump the handle. Since I had a pin and I was in the middle
of a project I put it back together and dialed the tailstock back in. I may
find it hard to break the habit of bumping the handle so eventually I am
sure it will fail again. When it does I would like to be ready with a
better solution. My first thought was to use a solid stainless dowel cut to
length. Throw some Loctite on it and call it a day. Drilling and reaming
for a nice light interferrence fit might be tedious, but its within my
capability. Just a few tenths so it stays in place, but can be driven out
easily enough. If the fit is to both parts, the cam and the shaft, there
shouldn't be any slop to allow the pin to cause wear. Are there any
issues with that? The other thought I had was to make a new cam that has to
be pressed onto the shaft eliminating another other possible play/wear
issue. A one piece shaft and cam is not a practical solution. I'd have to
drill out the side of the tail stock and the insert a bushing to support the
shaft. Not impossible, but a lot of unnecessary work and seriously
overkill. On the other hand it would probably outlast me. LOL.
This brings us to failure number two. After I put it back together I threw
a piece of stock in the chuck and turned a point to align the tailstock to.
Then I threw a dead center in the tail stock and started lining up the
points. When I got out my loupe I found the center was blunt. Looked like
maybe it was dropped. I couldn't see it with just my glasses on, but it was
clear to see with the loupe. Thinking maybe I dropped it and didn't
remember I got one out of the tool cart that had never been used before. It
was also blunt. It was a nice tiny dome, but it was blunt. Orders of
magnitude bigger than the tip on my turned point. Atleast it seemed uniform
so I dialed it in as best I could. I realize even with hardened and ground
steel handling is coming to take off needle tips from an object that heavy,
so maybe that's the norm. I don't know. Both centers came with the lathe so
perhaps they are just lower grade Chinese parts. Do all dead centers have a
domed tip when looked at under a glass?
Jim Wilkins
Nov 28, 2016, 12:48:46 PM11/28/16
to
"Bob La Londe" <no...@none.com99> wrote in message
news:o1hpo8$3io$1...@dont-email.me...
> ...Do all dead centers have a domed tip when looked at under a
> glass?
Ever hear of "Machinist's Elbow", caused by forgetting to remove the
center?
Since you may want to machine to finer precision than you can see, the
better way to center the tailstock is with a chucked indicator riding
on the conical surface. A quick check is to grab a milling edge finder
in both the spindle and tailstock chucks.
--jsw
news:o1hpo8$3io$1...@dont-email.me...
> ...Do all dead centers have a domed tip when looked at under a
> glass?
Ever hear of "Machinist's Elbow", caused by forgetting to remove the
center?
Since you may want to machine to finer precision than you can see, the
better way to center the tailstock is with a chucked indicator riding
on the conical surface. A quick check is to grab a milling edge finder
in both the spindle and tailstock chucks.
--jsw
Bob La Londe
Nov 28, 2016, 1:19:48 PM11/28/16
to
"Jim Wilkins" <murat...@gmail.com> wrote in message
news:o1hqjf$6t5$1...@dont-email.me...
I figured I'd use an indicator to dial it in closer when I need it. Not
sure I agree about the edge finder. I am sure my tail stock drill chuck
isn't "that" good, and I tend to leave the three jaw on the head stock for
speed. I keep trying to convince myself I can learn to be as fast as the
guys showing off on YouTube with their 4 jaw, but I don't think I have
another two ot three decades to master that skill. LOL.
news:o1hqjf$6t5$1...@dont-email.me...
sure I agree about the edge finder. I am sure my tail stock drill chuck
isn't "that" good, and I tend to leave the three jaw on the head stock for
speed. I keep trying to convince myself I can learn to be as fast as the
guys showing off on YouTube with their 4 jaw, but I don't think I have
another two ot three decades to master that skill. LOL.
rangerssuck
Nov 28, 2016, 3:28:41 PM11/28/16
to
On Monday, November 28, 2016 at 12:34:15 PM UTC-5, Bob La Londe wrote:
> This brings us to failure number two. After I put it back together I threw
> a piece of stock in the chuck and turned a point to align the tailstock to.
> Then I threw a dead center in the tail stock and started lining up the
> points. When I got out my loupe I found the center was blunt. Looked like
> maybe it was dropped. I couldn't see it with just my glasses on, but it was
> clear to see with the loupe. Thinking maybe I dropped it and didn't
> remember I got one out of the tool cart that had never been used before. It
> was also blunt. It was a nice tiny dome, but it was blunt. Orders of
> magnitude bigger than the tip on my turned point. Atleast it seemed uniform
> so I dialed it in as best I could. I realize even with hardened and ground
> steel handling is coming to take off needle tips from an object that heavy,
> so maybe that's the norm. I don't know. Both centers came with the lathe so
> perhaps they are just lower grade Chinese parts. Do all dead centers have a
> domed tip when looked at under a glass?
I don't know whether this is common knowledge or not, but an old machinist showed me how to get the alignment pretty damned close without a loupe. You bring the two points together, and capture a piece of flat stock between them - he used his 60 degree center gauge. Any misalignment becomes immediately obvious by the tilt of the metal.
> This brings us to failure number two. After I put it back together I threw
> a piece of stock in the chuck and turned a point to align the tailstock to.
> Then I threw a dead center in the tail stock and started lining up the
> points. When I got out my loupe I found the center was blunt. Looked like
> maybe it was dropped. I couldn't see it with just my glasses on, but it was
> clear to see with the loupe. Thinking maybe I dropped it and didn't
> remember I got one out of the tool cart that had never been used before. It
> was also blunt. It was a nice tiny dome, but it was blunt. Orders of
> magnitude bigger than the tip on my turned point. Atleast it seemed uniform
> so I dialed it in as best I could. I realize even with hardened and ground
> steel handling is coming to take off needle tips from an object that heavy,
> so maybe that's the norm. I don't know. Both centers came with the lathe so
> perhaps they are just lower grade Chinese parts. Do all dead centers have a
> domed tip when looked at under a glass?
Bob La Londe
Nov 28, 2016, 3:42:06 PM11/28/16
to
"rangerssuck" <range...@gmail.com> wrote in message
news:8f723468-87a6-49cb...@googlegroups.com...
* showed me how to get the alignment pretty damned close without a loupe.
* You bring the two points together, and capture a piece of flat stock
between
* them - he used his 60 degree center gauge. Any misalignment becomes
* immediately obvious by the tilt of the metal.
That makes perfect sense. I use a metal scale all the time to set the
height of tool holders. Don't know why I didn't think of doing that between
centers. Nice.
Jim Wilkins
Nov 28, 2016, 5:10:08 PM11/28/16
to
"Bob La Londe" <no...@none.com99> wrote in message
news:o1hsdl$e4f$1...@dont-email.me...
low jaw, rotate halfway to the high jaw, then adjust out half the
reading. Two revolutions get me within a few thousandths, then I
position the indicator for equal + and - deflections around a major
division.
--jsw
tdacon
Nov 28, 2016, 6:43:04 PM11/28/16
to
"Bob La Londe" wrote in message news:o1hpo8$3io$1...@dont-email.me...
>The other issues is the pin is in my opinion a little short for the job.
might consider reaming for a taper pin.
Tom
John B Slocomb
Nov 28, 2016, 7:29:34 PM11/28/16
to
On Mon, 28 Nov 2016 10:34:08 -0700, "Bob La Londe" <no...@none.com99>
wrote:
If you are worried that the tail stock center doesn't come to a sharp
point just grind it.
Back in the days of turning between centers it was a common job for
apprentices. Make sure that both the headstock and center were clean
and had no burrs, install the tail stock center in the head stock and
re-grind it with the tool post grinder. Usually both centers were
ground at the same time.
wrote:
point just grind it.
Back in the days of turning between centers it was a common job for
apprentices. Make sure that both the headstock and center were clean
and had no burrs, install the tail stock center in the head stock and
re-grind it with the tool post grinder. Usually both centers were
ground at the same time.
Bob Engelhardt
Nov 28, 2016, 9:51:40 PM11/28/16
to
On 11/28/2016 12:34 PM, Bob La Londe wrote:
> ... Do all dead centers have a
> ... Do all dead centers have a
> domed tip when looked at under a glass?
Why would one want it to be sharp? Other than for aligning the tail stock?
DoN. Nichols
Nov 28, 2016, 11:29:30 PM11/28/16
to
On 2016-11-28, Bob La Londe <no...@none.com99> wrote:
> Well, I just had my first failure with my PM 1440. The cam-lock on the
> tailstock broke. This lathe has been just so amazing compared to my other
> Chinese lathes that I got my feelings hurt. LOL.
[ ... ]
> Well, I just had my first failure with my PM 1440. The cam-lock on the
> tailstock broke. This lathe has been just so amazing compared to my other
> Chinese lathes that I got my feelings hurt. LOL.
> This brings us to failure number two. After I put it back together I threw
> a piece of stock in the chuck and turned a point to align the tailstock to.
> Then I threw a dead center in the tail stock and started lining up the
> points. When I got out my loupe I found the center was blunt. Looked like
> maybe it was dropped. I couldn't see it with just my glasses on, but it was
> clear to see with the loupe. Thinking maybe I dropped it and didn't
> remember I got one out of the tool cart that had never been used before. It
> was also blunt. It was a nice tiny dome, but it was blunt. Orders of
> magnitude bigger than the tip on my turned point. Atleast it seemed uniform
> so I dialed it in as best I could. I realize even with hardened and ground
> steel handling is coming to take off needle tips from an object that heavy,
> so maybe that's the norm. I don't know. Both centers came with the lathe so
> perhaps they are just lower grade Chinese parts. Do all dead centers have a
> domed tip when looked at under a glass?
tailstock, and mild centers, designed to go in the headstock and be
trued up before use. The hardened centers are more likely to have good
sharp tips.
But remember -- the center drills are designed to drill a small
hole followed by a 60 degree countersink so the point normally floats in
air -- or in whatever lubricant you may have put in the center hole. :-)
As an alternative way to center the tailstock -- do you have a
Blake Coax or one of the import clones thereof? If so, put the shank of
the coax in a collet or in the chuck (collet is better, if you have
them), and set the finger to either trace the ID of the Morse taper
socket in the tailstock ram -- or put the center in and trace on the OD
of it. Set the spindle to a slow speed (back gear) and adjust the
tailstock to minimize the wiggle of the needle. Note that some lathes
when new come with the tailstock just a little above center, so as the
tailstock wears, it first gets closer to center before it starts getting
worse, so you proably won't be able to find a truly wiggle free position.
Good Luck,
DoN.
--
Remove oil spill source from e-mail
Email: <BPdnic...@d-and-d.com> | (KV4PH) 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 ---
Bob La Londe
Nov 29, 2016, 6:36:25 PM11/29/16
to
"tdacon" <Tom-NOSPAM-@-REALLY-dacons.com> wrote in message
news:o1ifbo$ose$1...@dont-email.me...
That's probably the best idea yet for the next time it fails. A tapered
solid pin will be stronger, and it has the advantage of being able to be
tapped out. As opposed to a solid dowel Loctited in place that would also
require heat to knock out. It was already all back together with another
under engineered spring pin when I posted, but as I said before I expect it
to fail again.
Thank you.
news:o1ifbo$ose$1...@dont-email.me...
solid pin will be stronger, and it has the advantage of being able to be
tapped out. As opposed to a solid dowel Loctited in place that would also
require heat to knock out. It was already all back together with another
under engineered spring pin when I posted, but as I said before I expect it
to fail again.
Thank you.
Bob La Londe
Nov 29, 2016, 6:39:15 PM11/29/16
to
"John B Slocomb" <sloc...@inop.org> wrote in message
news:bifp3ct0c1as5gcto...@4ax.com...
precision. I do have a cheap crap coaxial indicator and a couple decent
Last Word indicators that haven't been dropped yet. I'm sure I can make one
of the work ok.
I don't have a tool post grinder. I am working on a tool post cross drill
though.
Bob La Londe
Nov 29, 2016, 6:39:42 PM11/29/16
to
"Bob Engelhardt" <BobEng...@comcast.net> wrote in message
news:o1iqk...@news6.newsguy.com...
Um... ok. LOL. Thanks Bob.
news:o1iqk...@news6.newsguy.com...
Bob La Londe
Nov 29, 2016, 6:43:03 PM11/29/16
to
"DoN. Nichols" <BPdnic...@d-and-d.com> wrote in message
news:slrno3q0vj.bu...@Katana.d-and-d.com...
I don't think eaither dead center I have is hardened. I may just have to go
out and spend a 3 dollars on one. There are times when I really need a dead
decenter rather than a live center for turning.
>
> But remember -- the center drills are designed to drill a small
> hole followed by a 60 degree countersink so the point normally floats in
> air -- or in whatever lubricant you may have put in the center hole. :-)
But... But... But... I might forget.
> As an alternative way to center the tailstock -- do you have a
> Blake Coax or one of the import clones thereof?
Crap clone. And a couple Last Words and an inspection mirror as an
alternative.
> If so, put the shank of
> the coax in a collet or in the chuck (collet is better, if you have
> them), and set the finger to either trace the ID of the Morse taper
> socket in the tailstock ram -- or put the center in and trace on the OD
> of it. Set the spindle to a slow speed (back gear) and adjust the
> tailstock to minimize the wiggle of the needle. Note that some lathes
> when new come with the tailstock just a little above center, so as the
> tailstock wears, it first gets closer to center before it starts getting
> worse, so you proably won't be able to find a truly wiggle free position.
I may try the pinched plate method just to see how it compares for results.
news:slrno3q0vj.bu...@Katana.d-and-d.com...
out and spend a 3 dollars on one. There are times when I really need a dead
decenter rather than a live center for turning.
>
> But remember -- the center drills are designed to drill a small
> hole followed by a 60 degree countersink so the point normally floats in
> air -- or in whatever lubricant you may have put in the center hole. :-)
> As an alternative way to center the tailstock -- do you have a
> Blake Coax or one of the import clones thereof?
alternative.
> If so, put the shank of
> the coax in a collet or in the chuck (collet is better, if you have
> them), and set the finger to either trace the ID of the Morse taper
> socket in the tailstock ram -- or put the center in and trace on the OD
> of it. Set the spindle to a slow speed (back gear) and adjust the
> tailstock to minimize the wiggle of the needle. Note that some lathes
> when new come with the tailstock just a little above center, so as the
> tailstock wears, it first gets closer to center before it starts getting
> worse, so you proably won't be able to find a truly wiggle free position.
DoN. Nichols
Nov 29, 2016, 8:32:01 PM11/29/16
to
On 2016-11-29, Bob La Londe <no...@none.com99> wrote:
> "DoN. Nichols" <BPdnic...@d-and-d.com> wrote in message
> news:slrno3q0vj.bu...@Katana.d-and-d.com...
>> On 2016-11-28, Bob La Londe <no...@none.com99> wrote:
>>> Well, I just had my first failure with my PM 1440. The cam-lock on the
>>> tailstock broke. This lathe has been just so amazing compared to my
>>> other
>>> Chinese lathes that I got my feelings hurt. LOL.
>>
>> [ ... ]
>>
>>> This brings us to failure number two. After I put it back together I
>>> threw
>>> a piece of stock in the chuck and turned a point to align the tailstock
>>> to.
>>> Then I threw a dead center in the tail stock and started lining up the
>>> points. When I got out my loupe I found the center was blunt. Looked
>>> like
[ ... ]
> "DoN. Nichols" <BPdnic...@d-and-d.com> wrote in message
> news:slrno3q0vj.bu...@Katana.d-and-d.com...
>> On 2016-11-28, Bob La Londe <no...@none.com99> wrote:
>>> Well, I just had my first failure with my PM 1440. The cam-lock on the
>>> tailstock broke. This lathe has been just so amazing compared to my
>>> other
>>> Chinese lathes that I got my feelings hurt. LOL.
>>
>> [ ... ]
>>
>>> This brings us to failure number two. After I put it back together I
>>> threw
>>> a piece of stock in the chuck and turned a point to align the tailstock
>>> to.
>>> Then I threw a dead center in the tail stock and started lining up the
>>> points. When I got out my loupe I found the center was blunt. Looked
>>> like
>>> so maybe that's the norm. I don't know. Both centers came with the lathe
>>> so
>>> perhaps they are just lower grade Chinese parts. Do all dead centers
>>> have a
>>> domed tip when looked at under a glass?
>>
>> Well ... there are hardened centers, designed to go in the
>> tailstock, and mild centers, designed to go in the headstock and be
>> trued up before use. The hardened centers are more likely to have good
>> sharp tips.
>
> I don't think eaither dead center I have is hardened. I may just have to go
> out and spend a 3 dollars on one. There are times when I really need a dead
> decenter rather than a live center for turning.
center in the headstock spindle, and the dead was one in the tailstock.
They were otherwise identical -- if the same Morse taper. Once we
started getting centers mounted in bearings so they could rotate in the
tailstock, the name drifted.
And the "live" one in the spindle was typically soft so it could
be trued *just* before mounting the workpiece. The "dead" one in the
tailstock was more likely to be hardened.
And have you ever seen a "half center"? A hardened center for
the tailstock with almost half of the diameter ground off so a facing
tool could get to the center hole to finish the end of a shaft. I've
got one of those -- but too small for my main lathe. Nice for doing
things that the ball bearing center won't allow.
>> But remember -- the center drills are designed to drill a small
>> hole followed by a 60 degree countersink so the point normally floats in
>> air -- or in whatever lubricant you may have put in the center hole. :-)
>
> But... But... But... I might forget.
Old lathes tended to have a cavity in the casting near the front
where the ram comes out, and a plug/dipper in there. It used to be
filled with white lead to use as a high-pressure lubricant for the dead
center -- before the world got scared to death of lead and mercury. :-)
>> As an alternative way to center the tailstock -- do you have a
>> Blake Coax or one of the import clones thereof?
>
> Crap clone. And a couple Last Words and an inspection mirror as an
> alternative.
>> If so, put the shank of
>> the coax in a collet or in the chuck (collet is better, if you have
>> them), and set the finger to either trace the ID of the Morse taper
>> socket in the tailstock ram -- or put the center in and trace on the OD
>> of it. Set the spindle to a slow speed (back gear) and adjust the
>> tailstock to minimize the wiggle of the needle. Note that some lathes
>> when new come with the tailstock just a little above center, so as the
>> tailstock wears, it first gets closer to center before it starts getting
>> worse, so you proably won't be able to find a truly wiggle free position.
>
> I may try the pinched plate method just to see how it compares for results.
state of your centers. I first learned about that in the manual for a
Unimat SL-1000 (where the headstock rotated instead of the tailstock
offset for turning long tapers). And they showed a double-edge razor
blade as the pinched plate. I often use a 6" scale for quick-and-dirty
center checking.
Enjoy,
edhun...@gmail.com
Nov 29, 2016, 10:12:54 PM11/29/16
to
For precise work, you mount the live center and turn a new point on it with the lathe compound. Then punch a witness mark on it, and a matching one on the center collet, so you can line them up again later for less-precise work.
>
> And have you ever seen a "half center"? A hardened center for
> the tailstock with almost half of the diameter ground off so a facing
> tool could get to the center hole to finish the end of a shaft. I've
> got one of those -- but too small for my main lathe. Nice for doing
> things that the ball bearing center won't allow.
>
> >> But remember -- the center drills are designed to drill a small
> >> hole followed by a 60 degree countersink so the point normally floats in
> >> air -- or in whatever lubricant you may have put in the center hole. :-)
> >
> > But... But... But... I might forget.
>
> In which case, let it remind you. :-)
>
> Old lathes tended to have a cavity in the casting near the front
> where the ram comes out, and a plug/dipper in there. It used to be
> filled with white lead to use as a high-pressure lubricant for the dead
> center -- before the world got scared to death of lead and mercury. :-)
--
Ed Huntress
Gunner Asch
Nov 29, 2016, 10:17:21 PM11/29/16
to
On 29 Nov 2016 04:28:36 GMT, "DoN. Nichols" <BPdnic...@d-and-d.com>
wrote:
Good post and good advise.
I simply use the razorblade method of tailstock center adjustment.
Works fine for most of my work, which is .000/+.001 at most
---
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wrote:
I simply use the razorblade method of tailstock center adjustment.
Works fine for most of my work, which is .000/+.001 at most
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edhun...@gmail.com
Nov 29, 2016, 10:21:26 PM11/29/16
to
On Tuesday, November 29, 2016 at 10:12:54 PM UTC-5, edhun...@gmail.com wrote:
<snip>
BTW, traditionally, dead centers are hardened only for the last 1/4 inch or so. All of mine are, and they're 60 years old or more. The hardening leaves a distinctively different color to the steel -- the result is a cone 1/4" long on the very end -- so it's easy to tell when one is a hardened center or not.
--
Ed Huntress
<snip>
BTW, traditionally, dead centers are hardened only for the last 1/4 inch or so. All of mine are, and they're 60 years old or more. The hardening leaves a distinctively different color to the steel -- the result is a cone 1/4" long on the very end -- so it's easy to tell when one is a hardened center or not.
--
Ed Huntress
Gunner Asch
Nov 29, 2016, 10:51:54 PM11/29/16
to
On 30 Nov 2016 01:31:13 GMT, "DoN. Nichols" <BPdnic...@d-and-d.com>
wrote:
>
on my 15x58
wrote:
>
> And have you ever seen a "half center"? A hardened center for
>the tailstock with almost half of the diameter ground off so a facing
>tool could get to the center hole to finish the end of a shaft. I've
>got one of those -- but too small for my main lathe. Nice for doing
>things that the ball bearing center won't allow.
I probably have 10 of those, from #1 MT to #5 MT..the headstock size
>the tailstock with almost half of the diameter ground off so a facing
>tool could get to the center hole to finish the end of a shaft. I've
>got one of those -- but too small for my main lathe. Nice for doing
>things that the ball bearing center won't allow.
on my 15x58
DoN. Nichols
Nov 30, 2016, 7:03:52 PM11/30/16
to
On 2016-11-30, Gunner Asch <gunne...@gmail.com> wrote:
> On 30 Nov 2016 01:31:13 GMT, "DoN. Nichols" <BPdnic...@d-and-d.com>
> wrote:
>
>>
>> And have you ever seen a "half center"? A hardened center for
>>the tailstock with almost half of the diameter ground off so a facing
>>tool could get to the center hole to finish the end of a shaft. I've
>>got one of those -- but too small for my main lathe. Nice for doing
>>things that the ball bearing center won't allow.
>
> I probably have 10 of those, from #1 MT to #5 MT..the headstock size
> on my 15x58
O.K. But does it also match the tailstock? I can't see using a
> On 30 Nov 2016 01:31:13 GMT, "DoN. Nichols" <BPdnic...@d-and-d.com>
> wrote:
>
>>
>> And have you ever seen a "half center"? A hardened center for
>>the tailstock with almost half of the diameter ground off so a facing
>>tool could get to the center hole to finish the end of a shaft. I've
>>got one of those -- but too small for my main lathe. Nice for doing
>>things that the ball bearing center won't allow.
>
> I probably have 10 of those, from #1 MT to #5 MT..the headstock size
> on my 15x58
half-center in the headstock. :-)
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