Dremel Tool Post Grinder

[hemmjo]

I made this tool a while ago. I inherited a small Dremel Moto-tool from my father in law. I had been wanting a tool post grinder for a while. After some thought I got an inspiration.



The nose of this tool easily screws off and on.



The thread pitch is about 11 tpi. The profile does not seem to exactly match standard 60˚ threads, but it is close. I decided to take a shot at making an adapter.



I mounted a piece of stock. Just using regular drill and a small boring bar made hole a little larger than the minor diameter of the plastic nose piece.



I cobbled together a set up to cut the internal threads.



I did not have an internal threading tool for my lathe. I made one from a damaged tap I had. Grinding away some teeth to leave only one that would serve as the cutter. It is ugly but it works.



The internal threading tool was clamped in place in my lantern tool post using steel blocks drilled to match the tap shank.



I threaded the part slowly. Stopping after I got close until the Dremel screwed into the adapter. It is a nice snug fit. The grinding forces are low, the fit is tight enough there is no need for a clamp on the threads.

[mklotz]

I've made several Dremel accessories using 3/4-12 as the thread to fit the nose. It's something of an odd-ball since UNC standard is 3/4-10 and UNF standard is 3/4-16. Dremel probably did that in an attempt to get folks to buy accessories from them. After all, how many people can single point threads in their home shops ? ;-)