Express CNC Ltd 07976562067

2012 Express CNC Limited  Tel +44 (0)7976562067



Express CNC Limited - Specialist repairer of CNC Machine Tools
CNC Machines repaired Fast!

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cnc repairs on Ajax, Bridgeport, Brother, Butler, Churchill, Colchester, Correa, Cincinnati, Daewoo, Dah Lih, DMG, Doosan, Emag, Emco, Feeler, Goratu, Geminis, Hartford, Hardinge, Harrison, Hitachi Seiki, Huron, Ikegai, Johnford, Kearns-Richards, Kia, Kitamura, Kuraki, Leadwell, Lagun, Makino, Matsuura, Mecof, Mori Seiki, Matrix, Nakamura, Nigata, OKK, Okuma, Star, Suga, Takisawa, Union, Victor, Wasino, Webster bennet, Yamazaki.


We are an Independent Company. We are not affiliated to any companies mentioned. All trademarks are acknowledged.

Ajax, Bridgeport, Brother, Butler, Churchill, Colchester, Correa, Cincinnati, Daewoo, Dah Lih, DMG, Doosan, Emag, Emco, Feeler, Goratu, Geminis, Hartford, Hardinge, Harrison, Hitachi Seiki, Huron, Ikegai, Johnford, Kearns-Richards, Kia, Kitamura, Kuraki, Leadwell, Lagun, Makino, Matsuura, Mecof, Mori Seiki, Matrix, Nakamura, Nigata, OKK, Okuma, Star, Suga, Takisawa, Union, Victor, Wasino, Webster bennet, Yamazaki.

Fanuc, Heidenhain and Fagor CNC controls repaired FAST.

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Ballbar Lathe test

The Renishaw QC20W Ballbar and it's software is an instrument which is used to measure geometric errors in a CNC machine tool . It is useful to detect inaccuracies induced by the CNC controller and servo drive systems.


Errors are measured by instructing the machine tool to Perform a circular arc or circle. Small deviations in the radius of this movement are measured by a ballbar and captured by the software.


The information is then plotted on the screen, to reveal how well the machine performed the test.



If the machine had no errors, the plotted data would show a perfect circle. The presence of any errors will distort this circle, for example, by adding peaks along its circumference and possibly making it more elliptical.


These deviations from a perfect circle reveal problems and inaccuracies in the numerical control, drive servos and the machine's axes. The software displays the errors and suggest ways to improve the machine.


The data can be saved and stored on a PC which is useful for providing historic data. This data can indicate problems that are about to arise.