So I have plenty of tools that work in 90% of my needs. But I am having difficult with squared receivers and getting into those corners with any type of rotary tool. Even with fine carbite bits the tool usually gets in the way.

Now I have an abrasive belt sander that sort of works, but is not nearly long enough for things like machine gun receivers.



Only thing I can think of is an Air file with a very long flat file.



anyone have any ideas?

where exactly are you buying those long shafted bits?

I'd venture a guess at eastwood.com where the pictures are hosted.

http://www.eastwood.com/long-reach-carbide-burr-set-4-piece.html

Worksharp knife sharpener with tool grinding attachment.  Then you'll have an awesome knife sharpener as well.

Just watch the RPM.

Long shanks are NOT suitable for much speed.