16mm OD Boring Bar Bushings

Everybody seems to make boring heads that take bars with 16mm shanks (Maritool, Iscar, etc.), but nobody seems to make bushings with an OD of 16mm to properly hold, say, a 1/2" or 3/8" boring bar. Does anybody know where to find these, or am I going to have to make them myself?


I'm aware that there are smaller bars available with an enlarged 16mm shank, but for some reason it seems like they're ALWAYS either way longer than I need or about .03" too short. Iscar makes 16mm OD bushings, but only with metric ID's, and only the type that's basically a drill bushing with a lengthwise slit, so there's no set screw to index the flat on the bar. (I prefer the types that either have clearance for the boring head's set screw or have a flat and a set screw of their own.)

Most of us would either make one or modify an off the shelf part to work.

Modify a 5/8" OD drill bushing. They're available in stainless steel if you don't want to deal with machining hardened steel.

The OD tolerance is typically +.0014 to +0.0017, so they're going to be slightly loose in a 16mm/0.630" bore, but only a couple thou off center.