Messages

11

General Mach Discussion / Re: Servo Basics

« on: January 20, 2013, 03:56:05 PM »

Jvaldes - thanks for the reply, however its too late, I already have the motors, yes probably overkill but I aim to transfer them at a later stage to a large gantry router.  So there is some planning involved.  I am considering a smooth stepper addin as this might solve my problem.

Thanks,

Andy 

12

General Mach Discussion / Re: Servo Basics

« on: January 20, 2013, 03:51:43 PM »

Hi Hood,

Ahh so the motors are capable of 5000mm/m but only by useing an external device like smooth stepper?  Without an external device if I use 100KHz / 2000 * 60 this gives a figure of 3000mm/m maximum or am I missing somthing?

Thanks,

Andy

13

General Mach Discussion / Re: Servo Basics

« on: January 20, 2013, 08:46:16 AM »

how do you derive the step per from the encoder, whats the calculation?  I was told to use 2000 however I still have no actual calulation to preform.  The encoder is 14bit where would I go from there?
I see what you mean about rapids, however it sounds like you have larger machinery and enclosed, I would be happy with around 5000mm/m but 3000mm/m is a good start point.  The servo is limited to 1000 rpm.  I have 16mm dia screws with a 5mm pitch.

Thanks,

Andy

14

General Mach Discussion / Re: Servo Basics

« on: January 19, 2013, 07:07:20 PM »

Ahhh ok, how does the encoder affect the rapid? I have a 14 bit encoder, so I belive this to be quite high...perhaps a smooth stepper would be advisable..
I also found the rapid overide in the settings, is this adviseable or not?

Thanks,

Andy

15

General Mach Discussion / Re: Servo Basics

« on: January 19, 2013, 06:25:45 PM »

Hi Hood,

Thanks for the response, do you alter the steps per value in acordance with the kernal speed.  Do you loose anything by having a higher kernal speed?  I have no interest in getting supper fast rapids (though it would be nice to see) would just like the system to work faster than 750mm/m.  Is there a calculation I can follow? Is smooth stepper recomended if you are using a servo system?  Sorry for all the questions.

Thanks,

Andy

16

General Mach Discussion / Servo Basics

« on: January 19, 2013, 05:33:19 PM »

Hi There,

I have bought a servo system (DMM tech) I am now in a process of learning how to set this up.  Here is my problem:

I have bought oversized motors, so I can direct drive the mill.  I am trying to work out the steps per value, I have been told to use the value of 2000 as my ballscrew is 5mm pitch and 1:1 ratio this seems right to me. However this seems to limit the mill to 750mm/m do I need to modify the kernal speed or is there another way to get higher speeds?  The encoder is a 14bit enconder, any help would be appriciated as I would like to understand how to set these values and the DMM documentation is of little help in this area.

Thanks,

Andy

17

General Mach Discussion / Re: Probing

« on: March 21, 2011, 08:46:56 AM »

Thanks Tweakie, 

Will this let me edge find as well as digitaly probe?

Cheers.

Andy

18

General Mach Discussion / Probing

« on: March 21, 2011, 06:47:33 AM »

After two years of modding my mill I finally have a working CNC machine (Big thanks to all here who helped me over that time)

I have a touch probe that works perfectly - however I would like to use it for edge finding.  I used to have a screen for that but now I cant seem to find it.  Does any one else have a way to edge find & center find a circle/round stock?

Many Thanks,

Andy

19

General Mach Discussion / Touch Probe skew angle?

« on: February 17, 2011, 10:01:44 AM »

Hello,

If i have a touch probe and I wanted to edge find a rectangle in a vice that has not been clocked in...can mach 3 compensate for the angle...and therefore account for the minor differences when it comes to make the cut? i.e say the rectange is not at 90 degrees on the table, but a 87.

Thanks,

Andy

20

General Mach Discussion / Re: Enco probe stopped working

« on: November 21, 2010, 11:18:05 AM »

Yeh i have done that...mine is called fuente master mill.  It just does not get any of the changes.

A