Mach3's Screw Mapping

[rgsparber]

This article explains how to use Mach3's Screw Mapping feature to reduce error on the Z axis of my RF-30 mill/drill. I have to admit, this adventure sure made my head hurt! But the results make it all worthwhile.


Screw Mapping will improve the accuracy of my RF-30 which uses a relatively sloppy gear train plus rack and pinion. Think what it can do for those with ball screws.

If you are interested, please see:


http://rick.sparber.org/ZSM.pdf



Your comments are welcome. All of us are smarter than any one of us.

[Captainleeward]

Good one, rgsparber.

[rgsparber]

Thanks Captain!

Rick

[kbalch]

Thanks Rick! I've added your CNC Error Correction Technique to our CNC category, as well as to your builder page: Rick Sparber's Homemade Tools. Your receipt:

CNC Error Correction Technique by Rick Sparber

tags: CNC, mill, software

[Paul Jones]

Rick,
Excellent and methodical. Thank you for taking the time to document your processes fro handling systematic vs. random errors. I am looking forward to seeing more articles about your CNC mill.
Paul

[DIYer]

Great stuff as usual, Rick. I will have to reread your PDF to fully grasp your tutorial.

[rgsparber]

Thanks guys. I continue to evolve the article as more is learned. Found another software bug yesterday.

[Altair]

Thanks for sharing such and educational article, Rick. As always, your contributions are invaluable. Looking forward to learning more from you!

Al

[rgsparber]

Al,

Thanks! Lots more to come.

Rick

[amirlach]

I have a question regarding the Screw Mapping. Where you printed.

"The data used by the software is limited to the nearest 0.001
inches. In my measurements and calculations, I will carry four places to the right
of the decimal and round to three before giving it to Mach3."

So basically I wanted to ask the reason for rounding down to three decimal points when I can measure to four. Is this software limitation in Mach3? I have linear magnetic encoders that measure to four decimal points and have a two micron resolution.

Mach3's screw mapping app seemed to accept the numbers I entered to four decimal points. It seems kind of a waste to round up, unless there is another reason for doing so.

So far I have only done my Y axis which is the shortest and seems to have the most accurately cut threads. Starting over will not be a big loss of time or effort at this point.


Thanks. amirlach