Grinding

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.

When grinding complex cutting tool profiles, attention should be paid to the software, the wheel and the tool blank for best results.

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?

A technique I call roll grinding is used to finish corners to match bend radii. Long weld seams that need to be rounded can be handled using a rolling technique with the disc grinder. It takes a little practice, but once you've mastered it, the results look just like a formed corner.

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.

Results from testing aluminum-oxide vitrified-bond wheels and diamond wheels in three different bond systems show the proper diamond roll dresser design, application methods and wheel specification can help manufacturing engineers achieve optimal results from continuous-dress, creep-feed (CDCF) grinding.

Spend enough time working in a machine shop and you're bound to pay a visit to the emergency room for a cut finger. First comes the sting as the ER physician injects you with a local anesthetic, then the tug of the thread as she drags the suturing needle, a type of surgical needle, through your skin. This traumatic experience is painful enough, but without the sharp edge imparted to those needles through special machines known as needle-point grinders, those sutures would feel as if the doc were using a darning needle from grandma's sewing kit.