Author Topic: 1997 DYNA MYTE DM4800 VMC to Mach3 Conversion  (Read 93369 times)

0 Members and 1 Guest are viewing this topic.

Offline Marty_Escarcega

  • Active Member
  • Posts: 65
    • View Profile
Re: 1997 DYNA MYTE DM4800 VMC to Mach3 Conversion
« Reply #100 on: April 30, 2012, 10:54:40 AM »
Most Industrial CNC mills/lathes etc require the control to output +-10v analogue command, the control receives position feedback from the motors encoder or resolver and the amplifiers need a speed command from the motor, often a tach or encoder.
If using one of the above they would put out the command voltage required by looking at the feedback. If your motors have resolvers then you would need to fit encoders as all of the aforementioned controllers require encoder feedback.
Hood

Thanks. It makes it an easy decison if the Mitsubishi servo amps and Freqrol spindle drive take analog inputs. I'm not sure yet. That's why I was asking and noted JH replaced all of his amps and motors. I haven't taken possession of the machine yet.
Thanks
Marty

Offline Hood

  • Mach4 Alpha
  • Posts: 25,774
  • Carnoustie, Scotland
    • View Profile
Re: 1997 DYNA MYTE DM4800 VMC to Mach3 Conversion
« Reply #101 on: April 30, 2012, 11:15:26 AM »
If they dont take analogue commands then they will take Step/Dir which would make it very simple, that however is very unlikely.

Hood

Offline Hood

  • Mach4 Alpha
  • Posts: 25,774
  • Carnoustie, Scotland
    • View Profile
Re: 1997 DYNA MYTE DM4800 VMC to Mach3 Conversion
« Reply #102 on: April 30, 2012, 11:18:07 AM »
Some drives can accept different command inputs such as the modern AC Drives and the Allen Bradley ones  I use. They can either take analogue of follower signals (which include Step/Dir) but again it is unlikely yours will be able to accept Step/Dir and are more likely to be analogue only.
If you had the model numbers you should be able to get a manual and see.

Hood

Offline JHChoppers

  • Active Member
  • Posts: 367
    • View Profile
    • JHCHOPPERS
Re: 1997 DYNA MYTE DM4800 VMC to Mach3 Conversion
« Reply #103 on: April 30, 2012, 02:53:11 PM »
Curious JH, where are you with the progress of your DM 4800 conversion?
Thanks
Marty

SLOW....  Been busy with other stuff.  

The servos could be reused but it was the amplifiers that could not.  So, for me, its easy to replace the servo and amplifier with a new matched set that has step/dir control from the get go.

Thanks
JH

Offline Hood

  • Mach4 Alpha
  • Posts: 25,774
  • Carnoustie, Scotland
    • View Profile
Re: 1997 DYNA MYTE DM4800 VMC to Mach3 Conversion
« Reply #104 on: April 30, 2012, 02:56:33 PM »
Why do you say they could not be reused?
Were they knackered or?
Hood

Offline JHChoppers

  • Active Member
  • Posts: 367
    • View Profile
    • JHCHOPPERS
Re: 1997 DYNA MYTE DM4800 VMC to Mach3 Conversion
« Reply #105 on: April 30, 2012, 03:58:09 PM »
Why do you say they could not be reused?
Were they knackered or?
Hood

The drivers/amplifiers could not be reused for Mach3 (or at least with technical skills).  The Medas CNC controller interfaced to them over a address/data busl.  I could not remove the driver high speed electronics (encoder feedback) from the high power amplifier side. 

However, I was able to sell the the integrated 3 axis driver/amplifier on ebay and pay for 2 of new servo motors and drivers!  LOL

Offline Hood

  • Mach4 Alpha
  • Posts: 25,774
  • Carnoustie, Scotland
    • View Profile
Re: 1997 DYNA MYTE DM4800 VMC to Mach3 Conversion
« Reply #106 on: April 30, 2012, 04:26:31 PM »
Ok, looks like they are unusual then and likely no use for Marty to reuse. Did they only accept commands via that bus ?
Hood

Offline JHChoppers

  • Active Member
  • Posts: 367
    • View Profile
    • JHCHOPPERS
Re: 1997 DYNA MYTE DM4800 VMC to Mach3 Conversion
« Reply #107 on: April 30, 2012, 06:47:00 PM »
Ok, looks like they are unusual then and likely no use for Marty to reuse. Did they only accept commands via that bus ?
Hood

His could be very different.  On the 4800 it used 2000W Servos, Meldas had other models that looked like they would work with Mach when I was looking/digging into my drivers.

Offline Hood

  • Mach4 Alpha
  • Posts: 25,774
  • Carnoustie, Scotland
    • View Profile
Re: 1997 DYNA MYTE DM4800 VMC to Mach3 Conversion
« Reply #108 on: April 30, 2012, 06:50:29 PM »
I know my friend has a big Mazak with Mits Amps and they are +-10v control but its old and I have no idea what model of Amps it has.
Suppose Marty will just have to get the model numbers and look and see.
Hood

Offline Marty_Escarcega

  • Active Member
  • Posts: 65
    • View Profile
Re: 1997 DYNA MYTE DM4800 VMC to Mach3 Conversion
« Reply #109 on: April 30, 2012, 08:24:11 PM »
Thanks Guys, I could not get the left side of the electronic cabinet open but it appeared that the servo amplifiers are separate. I spoke with the company that bought the machine new in the mid 90's. They ran that machine 5 days a week and for a few years 24/7. He says it won't hold tolerance anymore. Upwards of .015" out of tolerance. They never replaced the ball screws or thrust bearings in the machine. He was running when removed from service, sat outside for up to 8 months with a tarp over it, until the tarp deteriorated. They were keeping it to support a couple other 4500's that they had.

JH, I noted it appeared that your thrust bearings were replaced at some point in its life. I wonder if this machine is worth pursuing. I can source the thrust bearings. But  think the screws or ball nuts maybe worn out. Not sure if this is worth pursuing. Further thoughts?

JH, my apologies, I hope you don't feel I hijacked your thread.
Marty