Machsupport Forum

Mach Discussion => General Mach Discussion => Topic started by: Benchmark on July 12, 2006, 10:10:26 PM

Title: Craxy X Axis
Post by: Benchmark on July 12, 2006, 10:10:26 PM

Just as I started to get comfortable with Mach,  my  X axis went goofy.  When i jog it with the keypad or the jog menu, the DRO does not keep pace with the entered jog increment.  Example- with the jog increment set to .0010, the first tap of X+ Jog is .0011, next.0022, then .0028, then.0039, .0050.  With the increment of .0020 selected, the pattern is .0022, .0039, .0061, .0078, .0100.  Same with X-.  It seems to catch up in multiples of 5.  My computer is not hooked up to my mill yet.  Also, I can't get the individual "axes zero" buttons to work, but the "Ref All Home" button zeros everything.  Help me, help me, please!

Title: Re: Craxy X Axis
Post by: Brian Barker on July 13, 2006, 01:33:33 PM

Change your steps per unit to somthing like 20000 and that should fix your testing problem :)

Title: Re: Craxy X Axis
Post by: Benchmark on July 13, 2006, 08:53:31 PM

Thanks, Brian.  That seemes the fix the problem, but why?  Can't the jog feature be used in small increments?

Title: Re: Craxy X Axis
Post by: Brian Barker on July 13, 2006, 09:03:42 PM

If you have a vary small amount of steps per unit, 700 for this example. The smallest amount that the machine can move is .001429 inches. So if you tell Mach 3 to jog.002 it will move to .001429, I know this is not looking good but it is better then going to .002857 witch it the next increment that we have (.001429*2). The only way to fix this is to put on higher resolution encoders or add a reduction to the drive.


Hope that helps
Brian