Step Gauge improve accuracy of CNC machines
Using Step Gauge (check master) to improve the accuracy of CNC Machine
Currently, many companies use laser Interferometers to verify the positional accuracy of CNC machine. But, if we only verify the accuracy by laser interferometers at the production field which have a poor environmental conditions, the result would not be accurate because of the temperature, wind, humidity. During any one specific day, the results would be different between AM9:00 and PM3:00.
In order to solve this issue, more and more companies are now using the Step Gauge to test the CNC Machine, especially using high precision step gauge. Because it has the same expansion coefficients as the CNC Machine after 2-3 hours of idleness.
Step Gauge is used for calibrating CMM - Coordinate Measuring Machines. ISO 10360-2:2009 recommends manufacturers test products' linear dimensions with CMMs. And Step Gauge is now widely used for calibrating the CMMs. Click here for continued reading on Researchgate.
Citing a field inspection episode: A company who purchased a 3m Coordinate Measuring Machine from ZEISS of German, the ZEISS’ engineers used a 1m step gauge to inspect and calibrate this machine which sits in workshop.
(1) Step Gauge VS Laser interferometers
Contrast factor |
Step Gauge/Step Gage/Check Master |
Laser Interferometers | |
Accuracy |
Both of them almost have the same accuracy when they have been placed under a standard laboratory. But there are many factors which will affect the function of Laser Interferometers such as temperature, humidity, material properties. And it requires a high technological level for the operators. The measuring accuracy of Laser Interferometers will reduce once it goes out of laboratory. Step Gauge has same expansion coefficients as the machine which has been testing. So it can give a practical and precision result. | ||
Date Consistency |
The coefficient of thermal expansion of step gauge is same as grating ruler. We only need to put it together with the machine and wait for them to same temperature. In this way the measuring error caused by environment variation can be eliminated. So it has a good date consistency. The Laser Interferometers doesn’t have coefficient of thermal expansion. (big different from grating ruler), very sensitive for the temperature even with temperature sensor. | ||
Repeatability |
Step Gauge better than Laser Interferometers | ||
Date Drifting |
Step Gauge better than Laser Interferometers | ||
Stability |
Step Gauge better than Laser Interferometers | ||
Operator's skills needed |
One person with common technical skills |
At least two persons with special training | |
Field application |
Easy, convenient |
hard | |
Calibration Cost |
Low |
High | |
Item Cost |
Cost of Step Gauge is almost 1/10 of Laser | ||
Maintaining |
Simple |
Complex | |
Operating Life |
Step Gauge longer than Laser Interferometers | ||
Author: Andy Wang
Date: 2013-12-20
Email: trade2@anyii.com
Website: www.anyimeasuring.com