Tool tip attachment for ultrasonic impact grinding and method

A method for replacing a tool tip for an ultrasonic impact grinder having a tool with a proximal end adjacent a horn of the ultrasonic impact grinder and an opposing distal end, the method comprising:

• providing at least one threaded blind hole in the distal end of the tool;
• providing a replaceable tool tip having at least one threaded through hole in registration with each threaded blind hole, wherein a first threading of each threaded blind hole is different from a second threading of each corresponding threaded through hole;
• and
• rotating at least one headless differential screw fastener having first threads for engaging a respective threaded blind hole on a first end and having different second threads for engaging a respective through hole on a second end to attach the replaceable tool tip to the distal end of the tool and provide a preload force to the replaceable tool tip.

A replaceable tool tip system for an ultrasonic impact grinder, comprising:

• a tool formed of titanium, the tool extending axially and having a proximal end adjacent a horn of the ultrasonic impact grinder and a distal end including a plurality of first locating features;
• a pair of threaded blind holes disposed in the distal end of the tool;
• a replaceable tool tip formed of hardened tool steel, the replaceable tool tip having pair of threaded through holes in registration with each threaded blind hole, wherein a first threading of each threaded blind hole is different from a second threading of each corresponding threaded through hole, a proximal end of the replaceable tool tip includes a plurality of second locating features configured to interface with the plurality of first locating features, and a distal end of the replaceable tool tip includes a plurality of axially-extending walls in a substantially “π” shape;
• and
• a pair of headless differential screw fasteners having first threads on a first end for engaging a respective threaded blind hole, having different second threads on a second end for engaging a respective through hole, and having a recess on the second end thereof for engaging a rotating driving tool.