Metalworking (rec.crafts.metalworking) Discuss various aspects of working with metal, such as machining, welding, metal joining, screwing, casting, hardening/tempering, blacksmithing/forging, spinning and hammer work, sheet metal work.

Reply
 
LinkBack Thread Tools Search this Thread Display Modes
  #1   Report Post  
Posted to rec.crafts.metalworking
external usenet poster
 
Posts: 2,163
Default Homemade 2 spindle lathe preliminary results

After the long discussion about one spindle following another and
using a Gecko 320 servo drive I have the first test results. The servo
motor has a 500 line encoder mounted on it and the Gecko Drive reads
it in quadrature for a resolution of 2000 counts per revolution. I'm
using another of the same model encoder mounted to another motor
powered by a PWM power supply. This motor is the master and the motor
controlled by the Gecko is the slave. The master encoder is connected
to an LS7184 quadrature clock converter. The LS7184 accepts the
encoder signals and outputs step and direction signals which are fed
to the Gecko 320. As the speed of the master motor is varied the slave
follows PERFECTLY! There is no perceptible (to me) lag or overshoot.
And when spinning the master encoder at approximately 1 rpm the slave
follows perfectly with NO cogging. When the slave is commanded to move
only one step it does so without jumping as would a stepper when
operated with just switches or by just touching the wires to a power
source. Obviously the Gecko ramps up to speed to make movement as
smooth as possible. In fact, even though the Gecko is fed only
discreet step by step motion signals and position feedback is only in
steps it acts like the whole system is analog, when the motor is the
only analog device in the system. It looks like I can now grab a part
with two chucks at the same time without the worry of scuffing the
part.
Eric
  #2   Report Post  
Posted to rec.crafts.metalworking
external usenet poster
 
Posts: 790
Default Homemade 2 spindle lathe preliminary results

consider reading up on Bode plots and Nyquest Stability Criteria - then take
some calibrated data via a frequency sweep from .01 hz to 100 hz and see
what your mechanism is really doing



wrote in message
...
After the long discussion about one spindle following another and
using a Gecko 320 servo drive I have the first test results. The servo
motor has a 500 line encoder mounted on it and the Gecko Drive reads
it in quadrature for a resolution of 2000 counts per revolution. I'm
using another of the same model encoder mounted to another motor
powered by a PWM power supply. This motor is the master and the motor
controlled by the Gecko is the slave. The master encoder is connected
to an LS7184 quadrature clock converter. The LS7184 accepts the
encoder signals and outputs step and direction signals which are fed
to the Gecko 320. As the speed of the master motor is varied the slave
follows PERFECTLY! There is no perceptible (to me) lag or overshoot.
And when spinning the master encoder at approximately 1 rpm the slave
follows perfectly with NO cogging. When the slave is commanded to move
only one step it does so without jumping as would a stepper when
operated with just switches or by just touching the wires to a power
source. Obviously the Gecko ramps up to speed to make movement as
smooth as possible. In fact, even though the Gecko is fed only
discreet step by step motion signals and position feedback is only in
steps it acts like the whole system is analog, when the motor is the
only analog device in the system. It looks like I can now grab a part
with two chucks at the same time without the worry of scuffing the
part.
Eric



** Posted from http://www.teranews.com **
  #3   Report Post  
Posted to rec.crafts.metalworking
external usenet poster
 
Posts: 2,163
Default Homemade 2 spindle lathe preliminary results

On Fri, 5 Sep 2008 23:39:44 -0700, "William Noble"
wrote:

consider reading up on Bode plots and Nyquest Stability Criteria - then take
some calibrated data via a frequency sweep from .01 hz to 100 hz and see
what your mechanism is really doing

I don't have the equipment to do that. Maybe not even the mental
equipment. Instead the next test will involve clamping and unclamping
a cylinder mounted rigidly to one spindle. I haven't yet figured out
how to do that though. But if the collet is closed slowly around the
spinning cylinder, which will be painted with Dykem, it should be
obvious from the marks if there is relative movement between the two
spindles. It won't take much movement to damage cosmetically fussy
parts. But lots of times I run jobs where I put the parts into the
rotating collet and the part is not sctatched. The part is free of
course to accelerate to the spindle's speed and not held rigidly at
some speed that's supposed to be the same as the spindle.
Eric

wrote in message
...
After the long discussion about one spindle following another and
using a Gecko 320 servo drive I have the first test results. The servo
motor has a 500 line encoder mounted on it and the Gecko Drive reads
it in quadrature for a resolution of 2000 counts per revolution. I'm
using another of the same model encoder mounted to another motor
powered by a PWM power supply. This motor is the master and the motor
controlled by the Gecko is the slave. The master encoder is connected
to an LS7184 quadrature clock converter. The LS7184 accepts the
encoder signals and outputs step and direction signals which are fed
to the Gecko 320. As the speed of the master motor is varied the slave
follows PERFECTLY! There is no perceptible (to me) lag or overshoot.
And when spinning the master encoder at approximately 1 rpm the slave
follows perfectly with NO cogging. When the slave is commanded to move
only one step it does so without jumping as would a stepper when
operated with just switches or by just touching the wires to a power
source. Obviously the Gecko ramps up to speed to make movement as
smooth as possible. In fact, even though the Gecko is fed only
discreet step by step motion signals and position feedback is only in
steps it acts like the whole system is analog, when the motor is the
only analog device in the system. It looks like I can now grab a part
with two chucks at the same time without the worry of scuffing the
part.
Eric



** Posted from http://www.teranews.com **


  #4   Report Post  
Posted to rec.crafts.metalworking
external usenet poster
 
Posts: 3,984
Default Homemade 2 spindle lathe preliminary results

On Sep 6, 11:03 am, wrote:

I don't have the equipment to do that. Maybe not even the mental
equipment. Instead the next test will involve clamping and unclamping
a cylinder mounted rigidly to one spindle. I haven't yet figured out
how to do that though. But if the collet is closed slowly around the
spinning cylinder, which will be painted with Dykem, it should be
obvious from the marks if there is relative movement between the two
spindles. It won't take much movement to damage cosmetically fussy
parts. But lots of times I run jobs where I put the parts into the
rotating collet and the part is not sctatched. The part is free of
course to accelerate to the spindle's speed and not held rigidly at
some speed that's supposed to be the same as the spindle.
Eric



Another test would be to clamp a glass tube in both chucks.

Dan
  #5   Report Post  
Posted to rec.crafts.metalworking
external usenet poster
 
Posts: 2,473
Default Homemade 2 spindle lathe preliminary results

wrote:

Another test would be to clamp a glass tube in both chucks.


I'd clamp a piece of rubber tubing in both & see if it winds up.
Bob

--
Nota for President


  #9   Report Post  
Posted to rec.crafts.metalworking
external usenet poster
 
Posts: 3,146
Default Homemade 2 spindle lathe preliminary results

On Sep 6, 3:46*pm, Bob Engelhardt wrote:
wrote:

* Another test would be to clamp a glass tube in both chucks.


I'd clamp a piece of rubber tubing in both & see if it winds up.
Bob


I'd make two flywheels, the master thin and the slave thick, mark
reference lines on them and look for the conditions where the slave
starts to slip.

  #10   Report Post  
Posted to rec.crafts.metalworking
external usenet poster
 
Posts: 3,138
Default Homemade 2 spindle lathe preliminary results

On Sat, 06 Sep 2008 20:51:41 GMT, wrote:

On Sat, 06 Sep 2008 15:50:30 -0400, Bob Engelhardt
wrote:

Bob Engelhardt wrote:
wrote:

Another test would be to clamp a glass tube in both chucks.

I'd clamp a piece of rubber tubing in both & see if it winds up.
Bob


or a piece of stock in *each* (2 pieces) almost touching in the middle.
Make a scratch across the "joint" & see if it stays aligned.

--
Nota for President

Greetings Bob and Dan,
The glass tube idea will only work if the tube is weak enough to break
instead of forcing the spindles to keep in step. I think I have some
glass tube so maybe I'll try that. As to the rubber tubing and the
scratch I already know the spindles stay in line because of marks made
on discs at the end of each spindle. It's cool to spin one spindle
shaft by hand and watch the other keep up. It looks like the spindles
are one shaft. The discs are right next to each other with only about
.020" between the faces. So one motor spins cw while the other spins
ccw. So if the master spindle is unpowered and turned by hand the
other one keeps up perfectly. It's actually kind of creepy watching it
because I know there is no mechanical connection between the two.
Eric


There *must* be some relative torsional displacement because this is a
feedback control system depending upon an error signal. It could be
zero error at times of constant speed if the control system is PI
(proportional-integral) but there must be some error during speed
changes.

Incorporation of torque sensing could minimize this: sense torque
supplied by both drive motor and slave motor and have the control
system operate to minimize the difference.

You sorta have that now: torque difference is proportional to the
difference in encoder signals and the "twist" in the workpiece.

If the slave spindle need not provide any significant torque, then it
may just follow the load like a live center. In that case, the only
loads would be dynamic during accelerations and decelerations and the
load would drive the slave motor rather than vice versa. In that
case, if the torsional distortion in the workpiece is less than one
encoder count from drive spindle to slave motor there'd be no
excitation provided (or necessary) to the slave motor.


  #11   Report Post  
Posted to rec.crafts.metalworking
external usenet poster
 
Posts: 3,984
Default Homemade 2 spindle lathe preliminary results

On Sep 6, 1:51 pm, wrote:

Greetings Bob and Dan,
The glass tube idea will only work if the tube is weak enough to break
instead of forcing the spindles to keep in step. I think I have some
glass tube so maybe I'll try that.
Eric


If the glass tube forces the spindles to keep in step, would not
whatever you are using this for also force the spindles to keep in
step.

Dan

  #12   Report Post  
Posted to rec.crafts.metalworking
external usenet poster
 
Posts: 2,163
Default Homemade 2 spindle lathe preliminary results

On Sun, 07 Sep 2008 06:33:27 -0400, Wes wrote:

wrote:

So if the master spindle is unpowered and turned by hand the
other one keeps up perfectly. It's actually kind of creepy watching it
because I know there is no mechanical connection between the two.
Eric


What is the ultimate purpose of your effort? I seemed to have missed the original thread.

Wes

So that with a part spinning in one spindle the second spindle can
grab it without scratching it. Then the lathe can turnthe back side of
the part.
ERS
  #13   Report Post  
Posted to rec.crafts.metalworking
external usenet poster
 
Posts: 2,163
Default Homemade 2 spindle lathe preliminary results

On Sun, 07 Sep 2008 09:32:25 -0500, Don Foreman
wrote:

On Sat, 06 Sep 2008 20:51:41 GMT, wrote:

On Sat, 06 Sep 2008 15:50:30 -0400, Bob Engelhardt
wrote:

Bob Engelhardt wrote:
wrote:

Another test would be to clamp a glass tube in both chucks.

I'd clamp a piece of rubber tubing in both & see if it winds up.
Bob


or a piece of stock in *each* (2 pieces) almost touching in the middle.
Make a scratch across the "joint" & see if it stays aligned.

--
Nota for President

Greetings Bob and Dan,
The glass tube idea will only work if the tube is weak enough to break
instead of forcing the spindles to keep in step. I think I have some
glass tube so maybe I'll try that. As to the rubber tubing and the
scratch I already know the spindles stay in line because of marks made
on discs at the end of each spindle. It's cool to spin one spindle
shaft by hand and watch the other keep up. It looks like the spindles
are one shaft. The discs are right next to each other with only about
.020" between the faces. So one motor spins cw while the other spins
ccw. So if the master spindle is unpowered and turned by hand the
other one keeps up perfectly. It's actually kind of creepy watching it
because I know there is no mechanical connection between the two.
Eric


There *must* be some relative torsional displacement because this is a
feedback control system depending upon an error signal. It could be
zero error at times of constant speed if the control system is PI
(proportional-integral) but there must be some error during speed
changes.

Incorporation of torque sensing could minimize this: sense torque
supplied by both drive motor and slave motor and have the control
system operate to minimize the difference.

You sorta have that now: torque difference is proportional to the
difference in encoder signals and the "twist" in the workpiece.

If the slave spindle need not provide any significant torque, then it
may just follow the load like a live center. In that case, the only
loads would be dynamic during accelerations and decelerations and the
load would drive the slave motor rather than vice versa. In that
case, if the torsional distortion in the workpiece is less than one
encoder count from drive spindle to slave motor there'd be no
excitation provided (or necessary) to the slave motor.

Greetings Don,
The two spindles will be at the same speed. What I need is to make
sure that whatever speed the master spindle is turning at the slave
will match. If the part swap from the master spindle to the slave
spindle happens fast enough the part won't be scratched. So I really
don't care if the slave lags one encoder count as long as it lags
consistantly. And it appears that is happening right now. I will need
to take some pictures with a fast shutter to see if the marks always
line up.
Eric
  #14   Report Post  
Posted to rec.crafts.metalworking
external usenet poster
 
Posts: 790
Default Homemade 2 spindle lathe preliminary results

Greetings Don,
The two spindles will be at the same speed. What I need is to make
sure that whatever speed the master spindle is turning at the slave
will match. If the part swap from the master spindle to the slave
spindle happens fast enough the part won't be scratched. So I really
don't care if the slave lags one encoder count as long as it lags
consistantly. And it appears that is happening right now. I will need
to take some pictures with a fast shutter to see if the marks always
line up.
Eric


Eric - what you need to consider is dynamics, not just statics - it is not
clear from your limited requiements statement what kind of dynamic tracking
is required. I will absolutely guarantee however that under dynamic
conditions the two will not track. The amount of error depends on the
specific servo loop and its response time (and power) - whether the error is
a problem depends on your needs. I had suggested collecting the standard
frequency response data so you could evaluate this mathamatically. If
you'd rather not do that, then try this - mount an L shaped item (such as a
heavy allen wrench) in the main chuck. set up a a steel block so the L will
hit the block in about 1/2 revolution from "zero". Set the thing to zero,
fire off your high speed camera and hit the L as hard as you can with a
hammer (to make the main chuck rotate) - reveiw the high speed camera data
to see how good tracking is.


** Posted from http://www.teranews.com **
  #16   Report Post  
Posted to rec.crafts.metalworking
external usenet poster
 
Posts: 3,146
Default Homemade 2 spindle lathe preliminary results

On Sep 7, 3:46*pm, wrote:
I will need
to take some pictures with a fast shutter to see if the marks always
line up.
Eric


A strobe light would probably be more useful to you.

Make the two flywheels like I suggested. They can be thick and thin
squares of steel plate balanced on a lawnmower blade balancer, nothing
complicated or difficult. Press them onto shafts and put the thin one
in the master chuck as a reference and the thick one in the slave to
make it have to work hard to keep up.

Line up the corners, then accelerate the master rapidly and slow it
gradually. At or above some acceleration the slave will start to slip
and the corners will separate.

You could also watch the slave motor current as you twist it out of
line with the master. Possibly the slave will hold lock until the
current reaches a limit. If so, you could add a meter to see if the
current nears that limit in operation.

Then operate it below the maximum acceleration or current limit.
  #17   Report Post  
Posted to rec.crafts.metalworking
external usenet poster
 
Posts: 2,163
Default Homemade 2 spindle lathe preliminary results

On Sun, 7 Sep 2008 14:39:53 -0700, "William Noble"
wrote:

Greetings Don,
The two spindles will be at the same speed. What I need is to make
sure that whatever speed the master spindle is turning at the slave
will match. If the part swap from the master spindle to the slave
spindle happens fast enough the part won't be scratched. So I really
don't care if the slave lags one encoder count as long as it lags
consistantly. And it appears that is happening right now. I will need
to take some pictures with a fast shutter to see if the marks always
line up.
Eric


Eric - what you need to consider is dynamics, not just statics - it is not
clear from your limited requiements statement what kind of dynamic tracking
is required. I will absolutely guarantee however that under dynamic
conditions the two will not track. The amount of error depends on the
specific servo loop and its response time (and power) - whether the error is
a problem depends on your needs. I had suggested collecting the standard
frequency response data so you could evaluate this mathamatically. If
you'd rather not do that, then try this - mount an L shaped item (such as a
heavy allen wrench) in the main chuck. set up a a steel block so the L will
hit the block in about 1/2 revolution from "zero". Set the thing to zero,
fire off your high speed camera and hit the L as hard as you can with a
hammer (to make the main chuck rotate) - reveiw the high speed camera data
to see how good tracking is.


** Posted from http://www.teranews.com **

Greetings William,
The goal is to drive two spindle mounted chucks at the same speed so
after a part is machined on one end in the master chuck the slave
chuck can grab it. After the part is clamped in the slave chuck the
master chuck releases it. Then the rest of the work can be done on the
other end of the part. So the two chucks must be spinning at pretty
close to the same speed when the swap occurs. So if the master is
spinning at a certain fairly steady rate and if the slave can then
spin at the same rate I'll be OK. I realize that the slave will always
lag a little as far as angular position goes. But as long as the lag
is unchanging then the two spindles can match speeds.
Eric
  #18   Report Post  
Posted to rec.crafts.metalworking
external usenet poster
 
Posts: 2,163
Default Homemade 2 spindle lathe preliminary results

On Mon, 08 Sep 2008 19:02:11 -0400, Wes wrote:

wrote:

So that with a part spinning in one spindle the second spindle can
grab it without scratching it. Then the lathe can turnthe back side of
the part.


Is this high production? Going slow or stopping would seem to solve the problem. I'm
fairly our Mazak Multiplex's and Mori ZT2500Y's are using C axis indexing and are stopped
during the transfer.

Wes


Greetings Wes,
If I go to the trouble of putting an extra spindle on the lathe I want
to change parts while the chuck is spinning. It's amazing how only a
few seconds per part on a long run can add up. So If I can get the
spindles to match speed without too much trouble I wanna do it. And
not only that either. I just plain wanna figure it out.
Cheers,
Eric
  #19   Report Post  
Posted to rec.crafts.metalworking
external usenet poster
 
Posts: 2,163
Default Homemade 2 spindle lathe preliminary results

On Mon, 8 Sep 2008 16:50:13 -0700 (PDT), Jim Wilkins
wrote:

On Sep 7, 3:46=A0pm, wrote:
I will need
to take some pictures with a fast shutter to see if the marks always
line up.
Eric


A strobe light would probably be more useful to you.

Make the two flywheels like I suggested. They can be thick and thin
squares of steel plate balanced on a lawnmower blade balancer, nothing
complicated or difficult. Press them onto shafts and put the thin one
in the master chuck as a reference and the thick one in the slave to
make it have to work hard to keep up.

Line up the corners, then accelerate the master rapidly and slow it
gradually. At or above some acceleration the slave will start to slip
and the corners will separate.

You could also watch the slave motor current as you twist it out of
line with the master. Possibly the slave will hold lock until the
current reaches a limit. If so, you could add a meter to see if the
current nears that limit in operation.

Then operate it below the maximum acceleration or current limit.

Greetings Jim,
I already am using index marks to watch for slipping. And for sure a
strobe is the way to go. Now I'm going to have to make one. Time for a
google search for a simple circuit for one. One advantage I have is
that the two spindles will not be loaded any more than friction and
windage loads. They only need to match speeds during part changes.
Cheers,
Eric
  #20   Report Post  
Posted to rec.crafts.metalworking
external usenet poster
 
Posts: 59
Default Homemade 2 spindle lathe preliminary results

In article ,
wrote:

On Sun, 7 Sep 2008 14:39:53 -0700, "William Noble"
wrote:

Greetings Don,
The two spindles will be at the same speed. What I need is to make
sure that whatever speed the master spindle is turning at the slave
will match. If the part swap from the master spindle to the slave
spindle happens fast enough the part won't be scratched. So I really
don't care if the slave lags one encoder count as long as it lags
consistantly. And it appears that is happening right now. I will need
to take some pictures with a fast shutter to see if the marks always
line up.
Eric


Eric - what you need to consider is dynamics, not just statics - it is not
clear from your limited requiements statement what kind of dynamic tracking
is required. I will absolutely guarantee however that under dynamic
conditions the two will not track. The amount of error depends on the
specific servo loop and its response time (and power) - whether the error is
a problem depends on your needs. I had suggested collecting the standard
frequency response data so you could evaluate this mathamatically. If
you'd rather not do that, then try this - mount an L shaped item (such as a
heavy allen wrench) in the main chuck. set up a a steel block so the L will
hit the block in about 1/2 revolution from "zero". Set the thing to zero,
fire off your high speed camera and hit the L as hard as you can with a
hammer (to make the main chuck rotate) - reveiw the high speed camera data
to see how good tracking is.


** Posted from http://www.teranews.com **

Greetings William,
The goal is to drive two spindle mounted chucks at the same speed so
after a part is machined on one end in the master chuck the slave
chuck can grab it. After the part is clamped in the slave chuck the
master chuck releases it. Then the rest of the work can be done on the
other end of the part. So the two chucks must be spinning at pretty
close to the same speed when the swap occurs. So if the master is
spinning at a certain fairly steady rate and if the slave can then
spin at the same rate I'll be OK. I realize that the slave will always
lag a little as far as angular position goes. But as long as the lag
is unchanging then the two spindles can match speeds.
Eric


That's really neat and elegant. Hope it works!
-j


  #21   Report Post  
Posted to rec.crafts.metalworking
external usenet poster
 
Posts: 3,146
Default Homemade 2 spindle lathe preliminary results

You could watch both encoders on an oscilloscope. You might not catch
a single slip but you would clearly see multiple continuous ones.
  #22   Report Post  
Posted to rec.crafts.metalworking
external usenet poster
 
Posts: 2,163
Default Homemade 2 spindle lathe preliminary results

On Wed, 10 Sep 2008 03:38:55 -0700 (PDT), Jim Wilkins
wrote:

You could watch both encoders on an oscilloscope. You might not catch
a single slip but you would clearly see multiple continuous ones.

I already have digital readouts connected to each encoder. So I know
how many counts each one is producing. The counts match exactly after
everything stops. The numbers change way too fast to see how close
they are during rotation.
Eric
  #23   Report Post  
Posted to rec.crafts.metalworking
external usenet poster
 
Posts: 2,163
Default Homemade 2 spindle lathe preliminary results

On Wed, 10 Sep 2008 00:02:07 -0400, JoanD'arcRoast
wrote:

In article ,
wrote:

On Sun, 7 Sep 2008 14:39:53 -0700, "William Noble"
wrote:

Greetings Don,
The two spindles will be at the same speed. What I need is to make
sure that whatever speed the master spindle is turning at the slave
will match. If the part swap from the master spindle to the slave
spindle happens fast enough the part won't be scratched. So I really
don't care if the slave lags one encoder count as long as it lags
consistantly. And it appears that is happening right now. I will need
to take some pictures with a fast shutter to see if the marks always
line up.
Eric

Eric - what you need to consider is dynamics, not just statics - it is not
clear from your limited requiements statement what kind of dynamic tracking
is required. I will absolutely guarantee however that under dynamic
conditions the two will not track. The amount of error depends on the
specific servo loop and its response time (and power) - whether the error is
a problem depends on your needs. I had suggested collecting the standard
frequency response data so you could evaluate this mathamatically. If
you'd rather not do that, then try this - mount an L shaped item (such as a
heavy allen wrench) in the main chuck. set up a a steel block so the L will
hit the block in about 1/2 revolution from "zero". Set the thing to zero,
fire off your high speed camera and hit the L as hard as you can with a
hammer (to make the main chuck rotate) - reveiw the high speed camera data
to see how good tracking is.


** Posted from http://www.teranews.com **

Greetings William,
The goal is to drive two spindle mounted chucks at the same speed so
after a part is machined on one end in the master chuck the slave
chuck can grab it. After the part is clamped in the slave chuck the
master chuck releases it. Then the rest of the work can be done on the
other end of the part. So the two chucks must be spinning at pretty
close to the same speed when the swap occurs. So if the master is
spinning at a certain fairly steady rate and if the slave can then
spin at the same rate I'll be OK. I realize that the slave will always
lag a little as far as angular position goes. But as long as the lag
is unchanging then the two spindles can match speeds.
Eric


That's really neat and elegant. Hope it works!
-j

Me Too!
  #24   Report Post  
Posted to rec.crafts.metalworking
external usenet poster
 
Posts: 3,984
Default Homemade 2 spindle lathe preliminary results

On Sep 10, 4:49 pm, wrote:
The counts match exactly after
everything stops. The numbers change way too fast to see how close
they are during rotation.
Eric


Sounds like you are ready to try it out on some parts. I think it
will work a treat.

Dan

Reply
Thread Tools Search this Thread
Search this Thread:

Advanced Search
Display Modes

Posting Rules

Smilies are On
[IMG] code is On
HTML code is Off
Trackbacks are On
Pingbacks are On
Refbacks are On


Similar Threads
Thread Thread Starter Forum Replies Last Post
Spindle nose adapter for Delta-Rockwell 11" lathe (#25-100) with L-00 spindle Dan Allen Metalworking 7 April 3rd 14 06:12 PM
Homemade CNC 2 spindle lathe question [email protected] Metalworking 34 August 19th 08 07:10 PM
FOLLOWUP -- Lathe and VFD -- Some results Ignoramus30183 Metalworking 21 July 23rd 08 09:38 PM
Homemade Lathe Michael Woodworking 26 March 17th 06 05:54 PM
Results with Homemade Carbide Insert Lathe Toolholder woodworker88 Metalworking 24 November 3rd 05 12:11 AM


All times are GMT +1. The time now is 08:22 AM.

Powered by vBulletin® Copyright ©2000 - 2024, Jelsoft Enterprises Ltd.
Copyright ©2004-2024 DIYbanter.
The comments are property of their posters.
 

About Us

"It's about DIY & home improvement"