Hole centering adapter for hand grinder bit

I needed to drill pocket so for flat screw head. I've got drill bit that could do the job and drill stand, but no means to center it properly on each hole. And it was number of holes I had to do.

So 12 minutes later, including printing, I got one.

Inner diameter of the centering adapter is 8 mm. That is my bit diameter.

Print with hole on the bottom, no supports needed. I printed using PLA. Works fine. PETG is advisable as it is more flexible.

How to use:

Turn off grinder. Slide centering adapter onto machine. Turn it by hand to check if it is centered on bit. If it is centered peak of the adapter will stay in one place while turning.

Place hole in working piece below bit, lower bit down so centering adapter gets into hole, and push it down gently until it positions in the center of hole (by touching hole edge).

Fix working piece, raise bit, remove centering adapter, turn on grinder and drill.

Print instructions

Printer Brand: Prusa

Printer: I3 MK3S

Rafts: No

Supports: No

Resolution: 0.2

Infill: 25%

Filament: [ Prusament PLA ] grey

Notes:

Print with hole on the bottom, no supports needed. I printed using PLA. Works fine. PETG is advisable as it is more flexible.