A decent countersink holder was desired to replace the wooden dowel with a drilled hole. Decided to make it out of steel hex to avoid knurling and it was on hand. A 3" length of 3/4" steel hex was cut off with a hacksaw.
This length was held in the 3-jaw chuck and both ends were faced. About 7/16" on one end was reduced to 3/4" or to just get rid of the hexagonal corners. The lathe headstock was rotated 20° and a cone was cut on the end leaving a 7/16" diameter end. This was repeated on the opposite end, but in this case left a 1/2" diameter end. Both ends were chamfered with a file.
The smaller end was centered drilled and drilled up to 0.242" with a C drill to a depth of 1". This hole was then reamed 1/4" in diameter. This process was repeated on the larger end, but was drilled up to 0.368 with a U drill and reamed with a 3/8" reamer. Both holes were lightly countersunk. This resulted in a perfect sliding fit for both the 1/4" and 3/8" countersinks. Both gave a little "vacuum pop" as they were pulled out.
Positions were marked out for the set screw holes centered on one face and 3/4" in from each end. The holder was moved to the mill and held in the vise with one hexagonal corner in the vee groove. Both holes were center drilled, drilled with a #25 drill, and tapped 10-24. After cleaning up a bit the flat sides of the holder were sanded from 150 to 1000 grit. The entire holder was waxed with Johnson's Paste Wax.
A sweet Saturday morning project.
I use the holder multiple times on every project, wood or metal. So I made a second with a smaller and a larger countersink. I need one for every shop! Off to Cincinatti, so I have not polished it yet. (10/11/19) Sanded it initially on the new belt sander and then by hand up to 1500 grit. Filled the holes with paper towel bits and put on a coat of Johnson's paste wax.
