Machsupport Forum

Mach Discussion => General Mach Discussion => Topic started by: BrendanR on July 01, 2014, 12:36:37 PM

Title: Mach3 Step Time Variation
Post by: BrendanR on July 01, 2014, 12:36:37 PM

Hi,

I'm working on a cheap CNC router that is skipping steps like crazy. If you jog it for 20 seconds it will be off by about .005 in. I'm running Mach3 on a 32 bit Windows 7 tower. Here are some screen shots from Mach3's Driver Test program. It seems to be where the problem is coming from. Any suggestions would be appreciated.
(http://www.cnczone.com/forums/attachments/f288/241414d1404230293-mach3-step-time-variation-failing-png)(http://www.cnczone.com/forums/attachments/f288/241416d1404230322-mach3-step-time-variation-png)(http://www.cnczone.com/forums/attachments/f288/241418d1404230332-mach3-step-time-variation-specs-png)
Thanks!

Brendan

Title: Re: Mach3 Step Time Variation
Post by: Hood on July 01, 2014, 02:36:27 PM

No screenshots.

Try reducing the Velocity and Acceleration in Motor Tuning by maybe 50% and see how things go.
Hood

Title: Re: Mach3 Step Time Variation
Post by: BrendanR on July 01, 2014, 05:45:18 PM

Sorry about the screen shots.

I have tried everything from fast to slow, and every combination in between of velocity and acceleration without a change in the accumulative error. It looks to be a parallel port issue.

(http://www.cnczone.com/forums/attachments/f288/241414d1404230293-mach3-step-time-variation-failing-png)(http://www.cnczone.com/forums/attachments/f288/241416d1404230322-mach3-step-time-variation-png)(http://www.cnczone.com/forums/attachments/f288/241418d1404230332-mach3-step-time-variation-specs-png)

Thanks,

Brendan

Title: Re: Mach3 Step Time Variation
Post by: ger21 on July 01, 2014, 06:04:36 PM

You've got an issue with your PC. Your two images show pulse rates of 13000 and 19000. It should be fairly steady at around 25000, and not vary much at all. The graph should be a thin horizontal line with no spikes. Disregard the system excellent message, as it's often meaningless.
Go into the bios and turn off C1E or EIST if you have them.
Also disable any hardware devices that you don't need for Mach3, and see if it helps.

Title: Re: Mach3 Step Time Variation
Post by: BrendanR on July 02, 2014, 01:28:14 PM

Ok, I can't find setting in the bios for APIC, CIE, or EIST. What exactly does the DriveTest.exe check? Does it check the parallel port, or the Mach3 driver?

Thanks for the help tracking down the problems.

Title: Re: Mach3 Step Time Variation
Post by: BrendanR on July 02, 2014, 01:32:19 PM

Sorry about the images. This should work better. (photos attached)  ::)

Title: Re: Mach3 Step Time Variation
Post by: Hood on July 03, 2014, 03:34:22 AM

That is a terrible driver test result, it should be a flat line in the centre with very little disruption.
You could try doing some of the steps outlined in the Optimisation document to see if they help or you could try one of the many external controllers available or try a different computer.
Hood

Title: Re: Mach3 Step Time Variation
Post by: BrendanR on July 03, 2014, 02:00:32 PM

Ok, I looked and can't find the Mach3optimization.txt file. I found a link to it, but it was broken. Can someone post it please?

Thanks

Title: Re: Mach3 Step Time Variation
Post by: Hood on July 03, 2014, 04:05:49 PM

ftp://machsupport.com/Extra%20Information/XP_Optimization_Guide.txt (ftp://machsupport.com/Extra%20Information/XP_Optimization_Guide.txt)

Hood

Title: Re: Mach3 Step Time Variation
Post by: BrendanR on July 03, 2014, 04:12:02 PM

Thanks Hood!