Messages

41

General Mach Discussion / Re: Help on wiring an E-stop in.

« on: May 06, 2009, 11:59:46 AM »

I do similar.  2 pole NC E-stop.  One side connected to AC, other side connected to BOB.  I also using a latching relay for AC as belt/suspenders, so when power comes back on it all doesn't just fire right up.

and yes, it is Gecko that says do **not** switch the DC side.  First question they asked me when I spoke with tech support on the phone for warranty repair.

42

General Mach Discussion / Re: wrong parts measurment

« on: May 04, 2009, 01:55:21 PM »

Section 5.5.1

43

General Mach Discussion / MachMotion Screens & Touchscreen vs flat screen and mouse

« on: May 04, 2009, 10:21:04 AM »

Hey all,  I am just finishing up our first CNC router for use within our small company for making cabinets and some engraving work.  We dont have lots of spare cash and was wondering if the MachMotion Mach Screens combined with a touchscreen and worth the extra dollars.  Unfortunately MachMotion does not have a demo version of there product so I cannot try them out.  I loath to spend $200 on the screens just to try them.

thanks

44

General Mach Discussion / Re: Mach Ballbar test?

« on: May 01, 2009, 03:39:35 PM »

I know this is a very old post, but I wanted to bring it up as I have done a little pondering about building such a test tool.

Just for background, the Ballbar test is simple in concept:  it measures your CNC machine accuracy by connecting a special digital scale to your CNC.  One end of the scale attaches to your CNC head (router head, waterjet head, mill head) and the other end attaches to a fixed point on the table.  Then you program your CNC to do a circle around the fixed point.  The digital scale records, very accurately, the path taken then analyzes it and displays it on a computer screen with diagnostic information.

http://www.renishaw.com/en/6813.aspx



When I first saw this, I thought I could build a similar unit in the shop.  I would use a chinese micrometer scale hacked to send the data to a PC on the serial port (see http://www.shumatech.com/support/chinese_scales.htm ).  To handle the pivot on either end, use something similar to the ballbar: magnetic ball joints (see http://www.tmcmagnetics.com/ball_joint_assembly.html )

Finally it would be then an exercise in writing some software that would read the scalefrom the serial port and compare it against a known circle.

Thoughts? Comments?  Easier high accuracy ways to test accuracy of a CNC?

thanks