XING dressing technique inside the machine

Article by Haas Schleifmaschinen GmbH, Trossingen, Swabia

If you want to produce high-precision profile inserts, your tapered diamond grinding wheels need to be dressed on a regular basis. Haas Schleifmaschinen GmbH opts for the profile accuracy of the XING dressing technique inside the machine.

Haas has many customers who manufacture profile inserts, all of whom value maximum dimensional accuracy and surface quality. The Multigrind CU and Multigrind CA are the grinding machines most frequently used. The grinding tool of choice when it comes to machining profile inserts is often the tapered or V-shaped diamond grinding wheel, which has to be dressed – i.e. brought into the correct geometric form – on a regular basis to ensure exceptional grinding results.

XING dressing a tapered diamond grinding wheel, which is positioned at a 90° angle to the dresser wheel. Photos courtesy of Haas Schleifmaschinen

Dressing with profile accuracy

But the extremely precise tapered diamond grinding wheels often feature an edge radius of just a few hundredths of a millimeter and are correspondingly sensitive, which is why we at Haas opt for the XING dressing technique. The dresser wheel axis isn’t positioned parallel to the grinding wheel axis, as it is with other techniques, but rather at a 90° angle, meaning the silicon-carbide or corundum wheel often associated with other diamond grinding wheels can be used for dressing. Thanks to the NC-controlled process, the radius of the grinding wheel can be generated with the circumference of the dresser wheel, thus maintaining a consistent contact surface and pressure between dresser wheel and grinding wheel. The benefits of XING dressing include a lower pressure load and higher profile accuracy for the grinding wheel.

Machining a profile insert for machining on a Multigrind CU grinding machine.

Dressing without unclamping and rechucking

Like all other dressing techniques at Haas, XING dressing is also carried out inside the grinding machine, so there’s no need to unclamp and rechuck the grinding wheel. That has a positive effect on dimensional accuracy, while the grinding wheel boasts better radial and axial runout, making it possible to generate better surfaces. This is something you can actually hear while grinding – the wheel sounds much “healthier” during the grinding process.

Because of the good experiences we’ve had with XING dressing, this technique will be expanded for use in additional applications at Haas. In current projects, we’re applying the technique to profile grinding wheels, grinding pencils or quills and grinding wheels with other grain types, as well as ceramic and hybrid-bonded grinding wheels. As a result, many different wheel contours can be dressed using the Multigrind grinding machines. But this is only possible if the option for direct or indirect wheel probing is available. A noise sensing system is always required for setting up, optimizing, and operating the dressing process. When it comes to V-shaped wheels with a 30° included angle , the wear is highly dependent on previous wheel damage, meaning the existing wear behavior needs to be measured and compensated for.

XING dressing used to be called cross dressing

The mechanical engineers at Haas grin when asked why this dressing techniques is now called XING dressing and no longer cross-dressing. Cross-dressing has nothing to do with grinding technology in English, but instead refers to, according to Wikipedia, “the act of wearing items of clothing and other accoutrements commonly associated with the opposite sex.” What does XING mean? XING is the abbreviation for “crossing” in American English. And that’s a much better fit!