Messages

1

SmoothStepper USB / Re: SS and spindle motor control

« on: December 25, 2009, 05:26:25 PM »

Thanks Peter,

Any hints on the 3-wire spindle setup? (pwm, dir, stop)

2

SmoothStepper USB / Re: SS and spindle motor control

« on: December 25, 2009, 03:16:43 PM »

Recently I built an PWM-Analog converter of active filters, with adustable amplification for better calibration.

Now as I use it I had other questions raised:

* Does anyone how the PWM resolution changes with PWM frequency?
(Separately for PP output and for SS output)

** At Ports_Pins config, I can only set Step/DIR pins for spindle. IF I configure PWM, then STEP pin becomes the PWM output. OK. ANd what about the DIR pin?
 - If I set it to 0 (supposing I always rotate my spindle one direction only) then mach yells for an error.
 -- If I set it to a certain pin, then what will it do??? (I can configure separate relays for CW and CCW but I do not see where to  assign pins for them)
 --- What If (and this is my case in fact) want to use one pin for direction (HIGH=CW; LOW=CCW) and another pin for Spindle START/STOP (HIGH=GO; LOW=STOP) and a third pin for the PWM signal for speed control?

3

SmoothStepper USB / Re: PWM output for spindle

« on: December 25, 2009, 02:56:12 PM »

So I built my PWM-Analog converter of active filters, with adustable amplification for better calibration.
Now as I use it I had another question raised:

Does anyone how the PWM resolution changes with PWM frequency?
(Separately for PP output and for SS output)

4

General Mach Discussion / Re: How to use the Run From Here option.

« on: December 11, 2009, 12:57:42 PM »

Hi,

Same experience
So SET NEXT LINE is better (and works) i.s.o. Run from here? (did not dare testing it in live)

5

General Mach Discussion / Re: How to use the Run From Here option.

« on: December 11, 2009, 10:06:54 AM »

It is messy for me, too.
And when I run a program with subroutines, I can forget the run from here option, even when I press feedhold, and want to press cycle start again, it will not do a thing

6

Feature Requests / Re: Mechanical corrections from software

« on: November 21, 2009, 02:11:39 PM »

Well, the machine I want to use it with has industrial home + limit switches, plus index on the servos, so that would be not an issue, if service, or maintenance is needed (e.g. on bearings) I am aware that re-measurement might be needed...

7

Feature Requests / Re: Mechanical corrections from software

« on: November 21, 2009, 12:40:47 PM »

Dan, I`d do the measurements with a borrowed glass scale... Or borrow an interferometer or whatever from a tech. university nearby whatever, measuring it once would cost me far less than buying one single scale (and for 3 axis I`d need 3)

No reports on screw mapping might be due to noone is using it?
Whatever, then when time comes I will try it, and give report if I find problems. (but before the measurements I should make some dummy trials to see how it works for real)

Ger, thanks for the hint, I`ll have a look at that!
 

8

Feature Requests / Mechanical corrections from software

« on: November 21, 2009, 06:58:28 AM »

Hello,

The recent days I was wondering about a few features which have been mentioned earlier, but I do not know if it is possible to realize them.

Background story:
I have a High speed CNC machine with precision linear guides and ballscrew, integrated cooling for thermal stability, etc... However, this is not new.
Screws are renewed, accuracy is as it is... (Not the highest grade)
Linear guides are OK, but it had once a crash, and by measuring axis perpendicularity, at one point one axis has a small bend at a certain range.

I'd like to get some answers on 2 of them:

1. Screw mapping.
How is it nowadays? How well does it work?
Can I do the followings:
I mount an accurate measuring device on the axis, and go through the whole range of the axis. By comparing actaul and theoretical positions, and making a deailed screw map for each axis fore each "step" I could make it more accurate without mounting expensive glass scales...

2. Axis "linearization"
This one is for the bent axis...
Solution 1:  I change the wrong axis's components (quite expensive solution)
Solution 2: make comepnsation from software... Is it possible to somehow do this?
e.g give offset values for axis X when axis Y is at the range of 200-300... even different at different Z levels...
The offset equation is quite easy to define, I can make measurements to know the exact amount of deflections...
If Mach keeps track of absolute positions, then it should not be too difficult, no?

Thanks in advance!

9

General Mach Discussion / Re: How to use the Run From Here option.

« on: November 18, 2009, 05:45:52 PM »

Ook, With fresh head tomorrow I`ll check it. I cannot recall any command button called set next line
Thanks anyways!

10

General Mach Discussion / Re: How to use the Run From Here option.

« on: November 18, 2009, 05:31:34 PM »

No tool length comp. at all, that is sure.