0/T calibration test program

[stonker]

Has anybody developed a methodology to check repeatability of their VMCs by running at test pc., measuring it and control charting the results on a periodic basis? Any help on this topic is greatly appreciated. Thanks in advance, Rich

[Guest CNC Apps Guy 1]

A company I worked for did this. We had a part that had some shapes in it. A triangle, a square, and a half sphere. We would cut this part every 6 months or so. We would CMM the parts and track the results and if necessary call in a service tech to make the necessary adjustments. It's something I wish we would do at my present company.

 

HTH

[stonker]

James,

Was this just a piece of stock in a vise? How big and how far appart were these features? I would like to design a part that I would get alot of info out of it. Could I accomplish the same thing with periodic schedualing of a ballbar test? I've been reading many of your replys on other topics and really value your opinion.

Thanks,

Rich

[Guest CNC Apps Guy 1]

It was held in two vises, It was about 16 x 6 x 2. The features were several inches apart. Also there was a circle. The square was 4", the IC in the triangle was 3" The Sphere was a 1" Rad. with a .125 corner. We did it in Mild Steel, and we did it first thing in the morning every on a Monday every time.

 

Ball bar testing will only tell you how round you can make a circle - in all axes but still only a circle. Laser testing will give you linear accuracy but these do not give you results "under a load" which willl tell you REALLY how well your machine performs under a load.

 

HTH

 

[ 03-20-2003, 02:59 PM: Message edited by: James Meyette ]