Cleaning 3D Printed Recesses

Having used screwdrivers and other improvised tools to clean out various 3D printed recesses, it finally penetrated my thick consciousness that a boring bar is exactly the right hammer for the job:

Cleaning screw head recesses with a boring bar
Cleaning screw head recesses with a boring bar

In normal use, a boring bar’s head cuts mainly on its end surface, with the side cleaning up the hole’s periphery. Those edges remove droopy threads and Reversal zittage around a hole’s interior; an end mill works better to make the recess uniformly deeper.

I have a few sets of these things, with larger & smaller cutting ends and longer & shorter shanks, that I occasionally use for lathe boring and rarely for mill boring (in the manual mill, not the Sherline!). The smallest head in the collection is maybe 4 mm across, so there’s a definite lower limit on the size of the hole they’ll clear.

Hand-held while cutting plastic? They’ll last forever!

I should probably print up some handles…