Hello Guest it is April 16, 2021, 08:06:37 AM

Author Topic: Encoder suggestions  (Read 2808 times)

0 Members and 1 Guest are viewing this topic.

Encoder suggestions
« on: December 24, 2007, 12:34:47 PM »
I am beginning to convert my mini-mill to a CNC; this is my first conversion. I currently have the Xylotex board and stepper motors. Does anyone have any suggestions when it comes to encoders? Which encoders would you recommend?

Right now I am planning on using Mach 3. Will Mach 3 get the table position from the encoders and not just the counts on the stepper motors?

Thank you,
Ma*********

Offline Hood

*
  •  25,838 25,838
  • Carnoustie, Scotland
    • View Profile
Re: Encoder suggestions
« Reply #1 on: December 24, 2007, 12:52:28 PM »
Mach does not use encoders at all, it is open loop and relies on well tuned steppers.. If you have servos then your drives will need encoders  and the drives will provide a form of closed loop.
If you have steppers you can get the board from www.rogersmachine.net which will take encoder feedback and halt on a position error.

Hood
Re: Encoder suggestions
« Reply #2 on: December 24, 2007, 02:01:48 PM »
I looked at the board and am wondering how different it is from the board offered on CNC4PC (C10 - Bidirectional Breakout Board). This (and the other boards I've seen) have 4 inputs/outputs. Any suggestions for 5? I would like to do the standard 3 axis, a fourth axis for a rotary table, and an MPG.

Suggestions on where to start for looking at encoders?

Ma*********

Offline Hood

*
  •  25,838 25,838
  • Carnoustie, Scotland
    • View Profile
Re: Encoder suggestions
« Reply #3 on: December 24, 2007, 05:31:59 PM »
Any breakout should be able to do 5 axis but that will wipe out all of your outputs as there are only 10 on a parallel port. If you need more you are best to get 2 breakouts and get yourself a PCI Parallel port as a second port for Mach.
 Why do you need 5 anyway? you say¬† X Y Z and A (rotary table) then say MPG, a MPG would use 2 Inputs and not outputs.
 Are you planning on using servos or steppers? if steppers you dont need encoders. If you are using servos the motors you get may have encoders already fitted, if not then have a look at the ones from US Digital, I think thats what a lot of the guys here use, 500ppr is about the norm.

Hood


OOPS, there are 12 Outs  :-[
« Last Edit: December 24, 2007, 06:32:17 PM by Hood »