Ask The Grinding Doc

The Grinding Doc fields the following questions: 1. The grinding wheel manufacturer I work for wants to set up a basic lab for testing wheels and different Al2O3 grits. What's the best, most-economical way to do this? 2. I'm getting chatter on parts and am trying to determine if it's from grinding forces that are too high or from an out-of-balance wheel.

Our supplier in Asia is grinding hardened-steel parts and sending them to us for final processing. Some of them are cracking, so we're going to visit the supplier. What should we be looking for?

Ask the Grinding Doc Columnist Jeffrey Badger, Ph.D., responds to a question about the difference between "constant rpm" and "constant metal-removal rate" when it comes to grinding cams.

Dear Doc: I sell grinding wheels and frequently find myself pulling my hair out when recommending wheels to customers. One customer achieved great success with a resin-bond, 400-mesh diamond wheel when grinding ¾"-dia. carbide endmills.

Ask the Grinding Doc: When I ran out of single-point dressing diamonds and got desperate, I mounted a PCD insert to dress an Al2O3 wheel. Is there any danger in doing that?

Jeffrey Badger, Ph.D., fields a question from a shop getting "terrible burn on the shoulder" when cylindrical grinding steel parts with a straight plunge.

A machinist who is cylindrical-grinding threads into hardened steel using multiple-rib, vitrified-bond, aluminum-oxide wheels is experiencing breakdown of the thread root, and turned to the Grinding Doc for help.

The Grinding Doc offers an upbeat take on tri-grit wheels.

Dr. Jeffrey Badger, who authors the Ask the Grinding Doc column, answers questions about barreling and scrubber nozzles.

Dear Doc: I battle burn and long cycle times when grinding ODs in bearing. The wheel manufacturer has specified a series of wheel changes to solve the problem, but it means buying a lot of new wheels. What's your take?

Dr. Jeffrey Badger, Cutting Tool Engineering's Ask the Grinding Doc columnist, cautions readers not to be timid when slowing the workpiece speed to induce burn.

The sweet spot is where the grits in a grinding wheel optimally penetrate the workpiece to form a chip -- not too deep and not too shallow.