Messages

6571

General Mach Discussion / Re: Lost Steps

« on: July 07, 2011, 07:22:27 AM »

Hi Stefan,

Don't know if this helps but I couldn’t get anything, error wise, from your crossover file so went back to look at your earlier files.
I am trying to understand your “surfboard file top” and “surfboard file bottom” but the conventions used are rather unusual, at least for my machine.
You seem to have the X axis as the long axis and Z zero at the bottom of the work rather than the top. The final GCode lines of taking Z to zero, switching off the spindle then returning to X0, Y0 would break my cutter but you seem to have your Z axis reversed.
By convention +Z is usually upward (away from the work) and –Z is downward (towards the work).
I ran this file 4 times without error (just cutting air). I had to exchange the X and Y axis in the code so it would fit my machine table (the Y axis is usually the long axis by convention) and scale it down a bit but other than that it ran OK and my machine returned exactly to Z zero each time (using feeler gauges to check).
The GCode compilation is generally weird particularly with the jumping feed rates from F200 to F13000 for no good reason and there is a small Z axis glitch halfway along the long axis in both directions which I cannot understand so I would only score this 4 out of 10 for nice GCode to use.

Tweakie.

6572

General Mach Discussion / Re: when motors reverse, they stall then slowly pick up speed. HELP!

« on: July 07, 2011, 03:47:16 AM »

Vincent,

Try increasing your acceleration from 5 to 16 and save the settings then try again and see what happens.

Tweakie.

6573

General Mach Discussion / Re: Lost Steps

« on: July 07, 2011, 03:37:21 AM »

Brave try Stefan but for some reason the code did not attach. (try zipping the file perhaps).

Tweakie.

6574

General Mach Discussion / Re: Lost Steps

« on: July 07, 2011, 01:59:18 AM »

And yes I did save the settings and even opened up setting tab to be sure they changed.  You don't need to reboot Mach for Motor Setting Changes do you?

Sounds like you did it right.

If slowing the Velocity to 1000 made no difference then it blows my theory out of the water.

If it was a problem with Mach itself then I am certain it would have also been discovered by others, after all thousands of professional and semi-professionals use Mach on a daily basis.

Could you perhaps post or email me a section of GCode where this problem happens so I can try to duplicate the same error here ?

Tweakie.

6575

General Mach Discussion / Re: Lost Steps

« on: July 06, 2011, 05:24:46 AM »

Just answered my own question 

OK just looked at your .xml and the steps per mm for your Z Axis are only 83.333. Your velocity setting for this axis is probably way too high for this ratio thereby reducing the available motor torque considerably.
By comparison, for my Z Axis I use a velocity of 1500 but my steps per mm are over 500 and that represents a reduction gear ratio of around 6:1 over your 83.333.
I think you should reduce your Z Axis velocity to around 1000 or less and try again to see if the error still persists.

Tweakie.

6576

General Mach Discussion / Re: Lost Steps

« on: July 06, 2011, 05:00:26 AM »

It is kinda like an odyssey without really going anywhere

You are right there.

What are the steps per mm that you have set in motor tuning for the Z axis ?

Tweakie.

6577

General Mach Discussion / Re: when motors reverse, they stall then slowly pick up speed. HELP!

« on: July 06, 2011, 04:17:46 AM »

Hi Vincent,

Welcome to the forum.

There are quite a few Taig owners and Xylotex board owners here - someone will know the answer to this one.

I suggest you set the kernel to 25kHz initially, it is seldom necessary to go higher. The problem could be that the X and Y Axis Acceleration is set too low and the Velocity is set too high in motor tuning. You could perhaps go through the motor tuning procedure again.

Tweakie.

6578

General Mach Discussion / Re: Lost Steps

« on: July 06, 2011, 12:57:19 AM »

I understand your frustration S but your machine should follow the instructions it is given by Mach and be in exactly the position the Mach DRO says it is. When there is a discrepancy, as in your case, then for some reason steps have been lost (or gained). Gained steps are often caused by electrical noise pickup but steps gained in one direction can appear as steps lost when the axis travels in the opposite direction. Lost steps are often caused by insufficient drive torque or mechanical problems.

As your machine is belt driven, could the belt be slipping or jumping a tooth on the pulley ?.
Have you checked the tightness of all the grub screws associated with the drive train to the Z Axis ?.

Tweakie.

6579

General Mach Discussion / Re: Rotary + CV + G00 = Clunk

« on: July 05, 2011, 08:37:20 AM »

I think your problem relates to the exceptionally high speed you have set for the rotary axis and because it's movement is on the same GCode line as the X and Z you are getting a 'Blended Feedrate' which is higher than either your X or Z can individually tolerate - thus the 'clunk' and missed steps.

Tweakie.

6580

General Mach Discussion / Re: Motherboards-microATX that works

« on: July 05, 2011, 01:48:42 AM »

Glad you got it sorted John.

Thinking about your post, maybe it would be a good idea to have a post compiling all the motherboard types that do work well with the latest versions of Mach. 

Tweakie.