Machsupport Forum

Mach Discussion => General Mach Discussion => Topic started by: dwilliams56 on November 05, 2011, 12:28:45 AM

Title: Wacky axis movement
Post by: dwilliams56 on November 05, 2011, 12:28:45 AM
I fire up my router and do a ref all everything appears normal.

I jog an axis one inch and the spindle moves one inch. 

BUT, if I load a file then all three DROs move to a seemingly random location.  If I then move the spindle 1 or 2 inches the DRO only moves by some small amount, say .06 or something.

So if I try to move the Z axis 4 or 5 inches the Z hits the stop long before the Z axis DRO gets to 0.75in.

Anyone have any clues??

Thanks,
Don
Title: Re: Wacky axis movement
Post by: Tweakie.CNC on November 05, 2011, 03:37:34 AM
Have you checked your native units are set to inches (assuming you are working in inches) ??
Is the GCode file you are loading using inch units ??

Tweakie.
Title: Re: Wacky axis movement
Post by: dwilliams56 on November 05, 2011, 09:03:10 AM
Yes. That is one of the first things I thought of too.  But, the movement of the DRO has no relation to the movement of an axis.

Inches or MM makes no difference

Thanks for looking,
Don
Title: Re: Wacky axis movement
Post by: Tweakie.CNC on November 05, 2011, 09:50:24 AM
Quote
BUT, if I load a file then all three DROs move to a seemingly random location.  If I then move the spindle 1 or 2 inches the DRO only moves by some small amount, say .06 or something.

Don,

What file are you loading ??
Does this happen with any file ??

Tweakie.
Title: Re: Wacky axis movement
Post by: ger21 on November 05, 2011, 11:45:34 AM
This sounds like your native units are mm and your loading a file with G20 in it.
Title: Re: Wacky axis movement
Post by: dwilliams56 on November 05, 2011, 12:37:27 PM
Units don't matter. The movement of the DRO doesn't relate to the movement of the spindle.  Large movement of the spindle small change in DRO.

I tried a couple different files with same result.


Don
Title: Re: Wacky axis movement
Post by: ger21 on November 05, 2011, 12:56:31 PM
Does your g-code have a G21 in it? I'm pretty sure it's a units issue. Probably opposite what I said before. Machine set up in inches, and running a file in mm's.
Title: Re: Wacky axis movement
Post by: dwilliams56 on November 05, 2011, 02:27:07 PM
Gerry I have G20 in my Mach init string.

How do I check my native units?  This is a new machine (K2CNC).  The only software I received was the Mach profile.
Title: Re: Wacky axis movement
Post by: dwilliams56 on November 05, 2011, 02:29:24 PM
>>How do I check my native units

Never mind I found it in motor tuning.
Title: Re: Wacky axis movement
Post by: dwilliams56 on November 05, 2011, 09:57:43 PM
Does your g-code have a G21 in it? I'm pretty sure it's a units issue. Probably opposite what I said before. Machine set up in inches, and running a file in mm's.

Gerry you and Tweakie are right!

My machine was motor tune in MM... If I put a G21 in my code I can run my files:)

What do I need to be aware of to change the motor tuning to inches??

Thanks for your quick help!

Don
Title: Re: Wacky axis movement
Post by: Tweakie.CNC on November 06, 2011, 02:54:51 AM
Don,

If your motor tuning is in mm (and it is correct) then just convert the metric entries to inch units (eg. 320 steps / 25.4 = 12.5984 steps) and so on for Vel. and Acc. - remember to save each axis settings before proceeding to next axis. Also make sure Config. / Select Native Units is set to inches. Then test it thoroughly and if necessary make any small adjustments to Vel. and Acc. to obtain the best, 100% reliable, performance.

Tweakie.
Title: Re: Wacky axis movement
Post by: dwilliams56 on November 06, 2011, 09:04:08 AM
Thanks Tweakie
Title: Re: Wacky axis movement
Post by: Tweakie.CNC on November 06, 2011, 12:14:54 PM
My pleasure sir  ;)

Tweakie.