Sharpening Small Bits

[ToyMaker]

I have a Drill Doctor and it is great for 3/16 (or so) and up bits. Most of my bits are smaller! How do you folks deal with the little guys? And how small is practical? I don't think anyone really wants to mess with a #80 bit, but is it possible?

Yeah, yeah, - why bother? OK, I'm cheap! And I think it would be a good thing to know to save a trip to the store in the middle of a job. The easy way is to have a spare on hand, but that defeats the purpose of being cheap

robotic regards,

Tom

[Bill C]

The very small bits can be sharpened on a setup that includes a pin chuck with a Tee shaped body that includes a couple of small rollers at 180 degrees. Included in the set is a loup to see the bit tip for setting, a setting gage for tip angle (exposure), a fine six inch long stone (approx.280 or finer) and the chuck/roller with additional collets. These sets are probably still available commercially with a bit of searching. Being miserly, I enjoy not having to throw away dull micro bits, they sharpen surprisingly well, sometimes better than new.

This pin chuck device could well be fabricated and if anyone is interested, I will gladly include a photo or two...

Bill C.

[ToyMaker]

Bill:

I, for one, would be interested in seeing at least photos. And if available, drawings. I'd like very much to take a cut at building such a fixture .

robotic regards,

Tom

[Bill C]

I will measure and give dimensions as well if needed... as you can probably see, the pin chucking device has the basic 118 degree Tee shape for grinding the bit to that angle - more- let the bit expose a little more. Operation is done by rolling the wheel, dragging the bit on the stone and relieving the tip by rolling to the right as you pull it to you across the stone. Most simple to use and very good results can be seen quickly with the loupe. Keeping the lands equal is still the necessary portion, especially with very small bits.

Bill C.

[HuFlungDung]

If you practise sharpening a larger drill, you'll get more of a feel for how to do the little ones. Unfortunately, you're not getting any practise on the bigger ones because of the Drill Doctor: It's a vicious circle

[ToyMaker]

Bill:

I don't think dimensions are needed - the only critical measure seems to be the angle.

Feeling a bit thick here. I see the loupe, the 118 degree Tee, the small wheel on either wing(?), and the stone. But I don't see how all that goes together to sharpen a bit. Perhaps a few words of clarification for an apprentice chip sweeper (ha! you didn't know CSs had apprentices did you ).

Hu:
I could always give the good doctor a well-earned rest
Hmmm, I may do that just for the practice.

robotic regards,

Tom

[Bill C]

^

[ToyMaker]

Aaaaah Ha !!!
That picture is worth MANY words.
I might even be able to make one of those

Thank you very much Bill, appreciate it a lot.


robotic regards,

Tom

[mc_n_g]

This info and pics are grest. I have been wondering about what to do with all teh little stuff my father-in-law breaks or dulls.
Thanks,
mc_n_g

[handlewanker]

Hi all, I know this is coming late in the day for this subject but the drill sharpener mentioned and shown was/is known as "the Wishbone drill sharpener".
I first came across this item in the late 60"s and always wanted one so at last I designed one up from memory and made it.
So far I have sharpened 1/2mm drills quite easily, and up to 6mm.
If anyone wants a photo or design, mine differs from the bought item, I'll post some photos.
Ian.

[widgitmaster]

It's easy to see the ease of use a little fixture like that has to offer, but I for one have always had access to a 25x toolmakers microscope for checking and honing the edge on micro drills! Especially usefull when checking the edge of carbide for fractures!

It took me many years to learn how to stone an edge of a micro bit while looking through a 25x microscope, especially in an extreemly noisy and active shop!

If you are doing lots of micro drills, I would suggest you look for a microscope and a set of miniature diamond files and fine stones!

Eric

[Mcgyver]

wow old thread, good topic though. in trying to figure out how to sharpen very small drills, for those not familiar with it, remember that the traditional or at least common geometry on the end of the drill, where the clearance is sort of 'rolled' on is not the only way to sharpen a drill. Faceted sharpening is as good or better imo this where a primary and second clearances are ground on as flats - here's a pic of some i did http://i20.photobucket.com/albums/b2...eneddrills.jpg.

for small drills a hand held jig dragged across some fine emery cloth can be used to put a faceted point on - no grinding involved. Guy Lautard in one of his bedside readers describes how to make one.