Machsupport Forum

Mach Discussion => General Mach Discussion => Topic started by: nqwog on August 04, 2011, 08:32:47 PM

Title: CNC MISSING THE ODD STEP
Post by: nqwog on August 04, 2011, 08:32:47 PM

Hi Can anyone give me some advise on my Machine missing steps.
I have a TB6560 driver board. When machening I loose the odd step after a few minutes of working.
I disconnected the screw from the stepper and it did the same. I change to 36000mhz but still no difference.
I reduced the velocity and acceleration , it is slightly better but still looses a step every now and then.
It appears to be getting worse. My gut feel is the TB6560 is the problem(chinese driver so I guess I goy what I paid for.)
Am I on the right track?
Jim

Title: Re: CNC MISSING THE ODD STEP
Post by: Tweakie.CNC on August 05, 2011, 02:37:41 AM

Hi Jim,

Two things you could try;

Try selecting 'Sherline 1/2 Pulse Mode' in Config / Ports and Pins.
Try increasing the Debounce Interval in Config / General Config.

Your Kernel Speed should really be set to 25000Hz or 35000Hz.
The TB6560 is a good chip (assuming it is a genuine Toshiba and not a clone) so that Chinese board should be OK.

Tweakie.

Title: Re: CNC MISSING THE ODD STEP
Post by: BR549 on August 05, 2011, 10:37:38 AM

Check the polarity setting of the drive lines some drives "require" an active high or low OR they willl loose steps on the reversal of direction.

Just a thought, (;-)TP

Title: Re: CNC MISSING THE ODD STEP
Post by: ERP on August 05, 2011, 11:00:46 AM

You might also want to try increasing the pulse width, if you haven't already.

Title: Re: CNC MISSING THE ODD STEP
Post by: nqwog on August 05, 2011, 05:17:01 PM

Thanks to all for your advice.
I will try all your items and see what happens.
Jim