Mach3's Screw Mapping

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.

Good one, rgsparber.:bow:

Thanks Captain!

Rick

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:

<div id="blocks"> <div class="block b1 pngfix"> <div class="bimg"> <div> <a href="/cnc-error-correction-technique"><img src="/uploads/115542/cnc-error-correction-technique.jpeg" alt="CNC Error Correction Technique" /></a> </div> </div> <div class="head pngfix"></div> <div class="left pngfix"></div> <div class="right pngfix"></div> <div class="blockover b1 pngfix"> <div class="title"> <a href="/cnc-error-correction-technique">CNC Error Correction Technique</a> <span> by <a href="/builder/Rick+Sparber">Rick Sparber</a></span> </div> <div class="tags"> tags: <a href="/tag/cnc">CNC</a>, <a href="/tag/mill">mill</a>, <a href="/tag/software">software</a> </div> </div> </div> </div>

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

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

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

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

Al

Al,

Thanks! Lots more to come.

Rick

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

I was minimizing round off error. It is best to carry more places through the process and round off once at the end.

Rick

Thank you for the timely reply. I'll leave the settings as is at least until I can do some empirical testing with a sample cut like the one in the tutorial.


amirlach