- Joined
- Jan 1, 2014
- Messages
- 233
Have been trying to improve the grinding results on my swivel drill grinding attachment. Making a belt sander and an adjustable base for the fixture ( see thread "Belt Sander for Drills and Tool Bits") was a good start but was still not satisfied with drill line-up procedure. Extending drills ~ one diameter renders the small index tab useless as the flute retreats. Not extending the drill gives too much of a relief angle on the larger sizes so lining up the cutting edges vertically has to be done visually as other H-M members have said as well. Without some kind of a guide this is not exactly precise. The type of fixture does not lend itself to modification so just made a whole new one with the same geometry. Fixed for 118 degree tips but this all I have need for. The tailstock has a clamp and a totally revised clamp bracket was added to the body. This bracket with attached foot moves on a 20 degree forward angle which leads the drills forward automatically one diameter for size and incorporates an index guide (.025" wide x .032" high) milled into its front. The foot index rises and falls exactly on the V centreline. All drills are lined up 1/32" ahead of the index tip. Had to mount the foot on pins with a thumbscrew because the bracket would lock when put down tight on the drill. It is very easy to look down the guide and line up the cutting edge exactly parallel with the guide. Note is made of where the index sits on the margin (might sit slightly different on different drills) and is repeated when turning the drill over. Would appreciate any comments.
Canuck75
Canuck75
