Mystery object?

[Prowe]

Amongst the workshop tools that I inherited from my late father was a device that he had made, that I have no idea about and wondered if any of the forum members may be able to shed some light.
It consists of a laminated M/S block with a number of ¼” x ¼” holders that are a close sliding fit in the block. These holders are drilled along their centres with diameters that vary between 1/32” to 1/8” with a pinch screw to secure whatever. The holders slide in the block at 30 degrees to the horizontal and although it does not really show in the photos, the face without the tapped hole leans in towards the top at 7 degrees. My first thoughts where some kind of jig/fixture for sharpening small drills, but the angles do not seem to equate to anything that I know about drills.
Any suggestions gratefully received.


Regards to all,
Phil

[S.D.L.]

Is it for four facet drill sharpening, to the design done by DAG Brown in ME or EIM? Was there a seperate pad with a diamond hone in it?

Steve Larner

[teakfreak]

I think it is a drill grinding jig - see the article by L.A. Sullivan, ME Vol 146 p 1152, 1979

[Prowe]

Teakfreak,
Many thanks for this information, I have located the article and I now have an understanding of how this device is used, although whether I will be successful in using it is open to doubt. However I will give it a try and report back with my findings at a later date.
Many years ago I had access to one of the “Wishbone” drill sharpeners and no matter how carefully I followed the instructions I met with mixed results. On the last occasion I recall my attempts to sharpen a drill using one of these resulted in it refusing to cut at all, examination with a magnifier revealed nothing untoward that I could see and from that time I have never attempted to sharpen anything under 1/8” preferring to buy new instead. But maybe this device might make me revise my opinion.

Regards,

[simonwass]

I have 'sharpened' a #80 drill and it cut fine! I used a dremel and a fine grit stone checking with an eye loupe. I didnt check to see if it drilled a true 13thou hole though!
Grinding even a 1/16" bit should be easy on a normal grinder, sharpening is a bit of an art until you can watch someone who is good at it. Its all in the motion, best I can describe it is striking an arc with the arm, whilst rotating the wrist, whilst twisting bit between the fingers. I practiced with a cheap 6mm bit, big enough to see an effect, small enough to not be remving mush metal and cheap to buy if totally messed up. If your practice goes well you might only take off 1/8" from the drill!
I do have one of the jigs that clamps to the bench but I have no idea on how to use it.

[Shawki Shlemon]

I fully agree with Simon nothing simple and cheap beats free hand sharpening . An hour or two of practice on a med size drill and will master the art . I bought and made jigs and at the end I discovered the free hand sharpening is the best way . I can sharpen 1/16" drill bit easily, I do use magnifying glasses . Try it , it is satisfying .

[alanstepney]

I have a far easier way of sharpening drills.

An elderly friend whe spent his life as an engineer, pops in, and in return for a lunch at the local pub, spends a couple of hours sharpening all my drills.
He enjoys doing it, which he does far better than I do, and enjoys going out for lunch.

I reckon I get the best of the deal!