Messages

6771

General Mach Discussion / Re: PWM Mach Settings

« on: May 16, 2010, 12:55:12 PM »

Hi Dave,

I didn't get reliable results here (just a bench test) with a base frequency of 50 but at 100 I was able to change the mark/space ratio of the PWM signal from around 1% to 99% with the spindle speed slider.

Tweakie.

6772

General Mach Discussion / Re: PWM Mach Settings

« on: May 16, 2010, 12:03:27 PM »

Mach screenshots look OK to me, at least that is exactly what I would do. (have you tried minor tweaking like changing the PWM base to 100 etc.?)

Tweakie.

6773

General Mach Discussion / Re: PWM Mach Settings

« on: May 16, 2010, 11:20:18 AM »

Hi Dave,

If you have the benefit of an oscilloscope you could hook it up to your LPT pin 14 and observe the changing square wave PWM signal as you adjust the spindle speed slider within Mach (don't forget - you need to have a GCode loaded which issues the M3 command !!).
Then observe the 0 - 10 Volt signal at the Gecko pin 8.
If both the above are present then its your wiring (assuming nothing is broke).

Tweakie.

6774

FAQs / Re: Step and Dir signals

« on: May 15, 2010, 01:11:23 AM »

Also, what is the state of the dir pin when the motor is not supposed to turn?

The direction pin retains it's current state until it is changed by the next direction move - so it could be either state.

Tweakie.

6775

Show"N"Tell ( Your Machines) / Re: The Laser Project.

« on: May 14, 2010, 08:05:19 AM »

Nobody would want my brain Sam. If they were to discover any joined-up thinking it would only confuse them. 

Hey look -  Revolutionary Egg.

Tweakie.

6776

General Mach Discussion / Re: Pause for DRO Update

« on: May 14, 2010, 05:48:02 AM »

This subject has been discussed in great detail, both here and on the zone, with regard to tool position setting and probing.

My understanding of this is basically that the timing of a running macro and Mach itself are asynchronous therefore it is quite possible for a  macro to write to a DRO then read from that same DRO an incorrect value unless some form of synchronization is introduced. The command 'While isMoving()....Wend'  does just this and effectively causes the macro to wait for a 'handshake' from Mach to tell it that the last task has been completed and that it is now safe to proceed.

Tweakie.

6777

FAQs / Re: Step and Dir signals

« on: May 14, 2010, 05:28:57 AM »

Hi Nishant,

The step and direction signals can be configured either active high or active low within Mach3.
Your driver board will prefer either the 'high to low transition' for a step pulse (active low) or a 'low to high transition' but either way trial and error will tell if the driver board instructions do not. The direction bit set active low will produce stepper rotation in one direction and active high rotation in the opposite direction and this is set to match the machine axis etc.

Hope this helps,

Tweakie.

6778

Show"N"Tell ( Your Machines) / Re: The Laser Project.

« on: May 13, 2010, 01:29:32 AM »

Thanks Guys, you have given me new ideas to try.

Tweakie.

6779

Show"N"Tell ( Your Machines) / Re: The Laser Project.

« on: May 12, 2010, 11:17:51 AM »

Interesting but not quite what I had intended. This Calcium Carbonate is tough stuff and I was intending to go right through but despite two passes, no luck. Increasing the power setting was a total failure resulting in a burned mess.

Back to the drawing board with this one – I am sure it is feasible anyone have any ideas ?.

Thanks to Switcher for the DXF http://mydxf.blogspot.com/

Tweakie.

6780

General Mach Discussion / Re: Making a laser cutter

« on: May 12, 2010, 10:52:05 AM »

 

Not sure I fully understand but the laser lens assembly is lifted out and the spindle motor fitted in it's place when I need it. The black tube surrounding the spindle motor is it's air cooling jacket (there is a fan in there, at the top).

Tweakie.