Hello Guest it is July 18, 2019, 12:03:57 PM

Author Topic: Manual to cnc lathe retrofit? feaseable?  (Read 22347 times)

0 Members and 1 Guest are viewing this topic.

Re: Manual to cnc lathe retrofit? feaseable?
« Reply #10 on: May 18, 2008, 02:31:56 PM »
So is the differance between using stepper motors and ac servo motors just about speed? or power?

Kev

Offline Hood

*
  •  25,849 25,849
  • Carnoustie, Scotland
    • View Profile
Re: Manual to cnc lathe retrofit? feaseable?
« Reply #11 on: May 18, 2008, 03:35:02 PM »
AC Servos have Speed, also have a continuous rated torque, that torque is from zero to full rated RPM, acelleration is also extremely rapid with servos. Servos also have encoders which close the loop between drive and motor.
 Big disadvantage with AC Servos is the cost.
 
 If not in a hurry steppers can be used, they do lose torque as speed increases and can lose position if the going gets tough, HOWEVER with properly sized steppers the torque will not be an issue and they wont loose steps because they have been sized as to have enough torque at all forseable conditions.
 Stepers are very cheap when compared to AC Servos.

 For big machines steppers are not a viable option because you will have to trade far too much speed and acelleration for the sake of accuracy.

Just my opinions based on my stepper Bridgeport CNC and my AC Servo Computurn Lathe.

Hood

Offline Hood

*
  •  25,849 25,849
  • Carnoustie, Scotland
    • View Profile
Re: Manual to cnc lathe retrofit? feaseable?
« Reply #12 on: May 18, 2008, 03:40:29 PM »
BTW Kev are you in the UK, If so where about? I am in Scotland as can be seen to the left :)

Hood
Re: Manual to cnc lathe retrofit? feaseable?
« Reply #13 on: May 18, 2008, 03:49:12 PM »
Hood
Yes im from the UK, i live near Bolton, Lancashire however im currently workng in Iraq, which is why this project is a way off, timewise. I have seen your lathe on youtube and it looks the same size as my cazeneuve, i was tempted to buy it when Budget machinary had it.  ;D

Offline Hood

*
  •  25,849 25,849
  • Carnoustie, Scotland
    • View Profile
Re: Manual to cnc lathe retrofit? feaseable?
« Reply #14 on: May 18, 2008, 04:30:46 PM »
Well if your lathe is anywhere near the size of the Computurn you definitely dont want steppers, unless that is  you want to start it machining before you leave for Iraq, then it should be finished as you arrive home :D
 
 Hood
Re: Manual to cnc lathe retrofit? feaseable?
« Reply #15 on: May 18, 2008, 04:34:27 PM »
Thanks for the advice
Im just reading your thread (just got a lathe to retrofit). Very interesting! ;D

Offline Hood

*
  •  25,849 25,849
  • Carnoustie, Scotland
    • View Profile
Re: Manual to cnc lathe retrofit? feaseable?
« Reply #16 on: May 18, 2008, 04:39:54 PM »
Yes that was a long learning curve for me, and expensive when I was trying to run these great big DC motors from the small drives, smoke was a common occurrence :D I have learned a lot from doing the lathe and I am now applying that knowledge to my latest retrofit which is a Beaver Mill, twice the machine that the Bridgeport is :)

Hood
Re: Manual to cnc lathe retrofit? feaseable?
« Reply #17 on: May 18, 2008, 04:40:48 PM »
Thanks RICH
Ive certainley got lots to think about, part of me is saying DO IT anyway, if only for the experiance.

Kev

Offline Hood

*
  •  25,849 25,849
  • Carnoustie, Scotland
    • View Profile
Re: Manual to cnc lathe retrofit? feaseable?
« Reply #18 on: May 18, 2008, 04:54:52 PM »
Kev
 Its quite hard to tell a size of a lathe from pics but often a good way is the size of the chuck in relation to the rest of the machine, any idea what size the chuck is on your cazeneuve?

Hood
Re: Manual to cnc lathe retrofit? feaseable?
« Reply #19 on: May 18, 2008, 05:13:49 PM »
It has a 12 inch chuck in the pics, swing is 595mm, and approx 40 inches between centres. Heres a pic ive lifted off the web to give an idea of its size.
Hopefully pic will attach.
Kev