Sharpening tiny drills

[mklotz]

The best way to sharpen small drills is to buy them by the dozen and discard the dull and broken ones.

Nevertheless, there's always the inevitable late Saturday shop session where you break your only #64 drill and you're dead in the water until you can order a new one on Monday. Then it's nice to have a way to touch up a buggered drill.

Here's an approach I use on those rare occasions. Its operation depends on the fact that, for very small drills, there is no need to try to make a conical point as found on larger drills. Simple flat facets that create the cutting edges are all that is needed. (In some senses, this jig embodies the same principle that gemstone diamond faceters use, albeit with only a single faceting angle.)

The device consists of a small pin vise fitted into a piece of aluminum angle.

The pin vise is free to rotate about its axis and, when properly oriented, can be locked in place with the small black plastic finger knob where the arms of the L meet. After mounting the drill in the pin vise collet, the pin vise is rotated to align the drill web with the line where the two arms of the L meet.

Then it's a simple matter of turning the assembly over and stroking the drill along a grinding stone as shown in the following photo...

The top of the angle should be horizontal so a spacer the same height as the grind stone is used. (At my desk, my calculator was handy. In the shop, a block of aluminum is used.)

Now to create the matching facet on the other side of the drill tip, it's a simple matter of flipping the fixture over and repeating the operation...

Inspect the tip with a loupe. If the facets aren't quite equal, a quick swipe or two will fix it. Since the drill to stone angles are preserved by the jig, you won't have multiple facets.

Credit where credit is due...

This jig was made by and given to me by Norm Wells, a very good friend. I'm not certain if the design is Norm's. I seem to remember seeing something similar in a magazine but I could be remembering diamond faceting tools.

[kbalch]

Thanks Marv! I've added your Drill Sharpener to our Sharpening category, as well as to your builder page: mklotz's Homemade Tools. Your receipt:

Drill Sharpener by mklotz

tags: vise, drill, sharpening

[Ralphxyz]

Thanks Marv, definetly on my todo list!!

Ralph

[old_toolmaker]

Mklotz,

That is a great idea. I have seen something similar before but I don't think it was that simple. I am just assuming it gives a point angle of 90 degrees instead of the usual 118 degrees. Is that correct?

[mklotz]

Mklotz,

That is a great idea. I have seen something similar before but I don't think it was that simple. I am just assuming it gives a point angle of 90 degrees instead of the usual 118 degrees. Is that correct?

The point angle is controllable by adjusting how far the drill extends from the pin vise.

[Frank S]

Marv this is one of those tools where you go now why didn't I think of that. For me anything smaller then 5/64" is very hard to to but I use the hand and eye method for sharpening most bits when they get that small and smaller it is hard for me to see the edge well enough to get a good relief angle. with one of these I might be able to rotate the bit close enough to get my desired trailing edge relief.

[old_toolmaker]

mklotz,

Your statement: "The top of the angle should be horizontal so a spacer the same height as the grind stone is used. (At my desk, my calculator was handy. In the shop, a block of aluminum is used.)" through me off. If you did it the way as explained and shown you would have a 90 degree point angle.
But, from what you are saying you can extend or retract the drill to accommodate a different point angle. This would therefore change the top of the angle from horizontal to something different. Am I visualizing that correctly?

[mklotz]

mklotz,

Your statement: "The top of the angle should be horizontal so a spacer the same height as the grind stone is used. (At my desk, my calculator was handy. In the shop, a block of aluminum is used.)" through me off. If you did it the way as explained and shown you would have a 90 degree point angle.
But, from what you are saying you can extend or retract the drill to accommodate a different point angle. This would therefore change the top of the angle from horizontal to something different. Am I visualizing that correctly?

Yes, you are correct. Now that I read what you quoted, I'm not sure why I wrote it; there's no real need for the angle to be horizontal.

[old_toolmaker]

Marv,

Thanks for the clarification.
That makes perfect sense to me now.
That is a great, simple tool and strait forward to build. I need one of my own now!
Thanks for sharing.

[ncollar]

Marv
You are just too modest, it is a wonderful tool. There is nothing like a keen edge on a drill bit.
Nelson