Dear agony aunty/uncle knifemaker supremes..
I keep breaking 2mm drill bits trying to drill some nice small pin holes through a fresh peice of anealed tool steel ( a file mark removed old file) It's being a tough nut to crack. Sometimes i can drill easilly through these things, however this time it seems to just want to eat all my drill bits :(.

Should i
a- anneal it several times?
b- hit it with something heavy untill the forge gods allow the holes to appear by magic?
c- cry into my hot coco?

Please advise...
Yours sincerely
A befuddled noobie "knifemaker" (knifebodger) (hobbyist)

Best regards
Paul
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Now when you say tool steel exactly what are you using? If it is an air hardened steel you will not be able to anneal it without some serious HT setup. If it is oil or water hardened then I would soak at critical and burry it in vermiculite. Then use a slow speed on the drill. If that doesn't work, buy carbide bits.

Be sure you get your heat even on the anneal.

Clean any scale off before you drill.

Use sharp bits.

Lube your bits (I use lard for thin stock / small bit drilling).

Low speed, firm pressure.

Sometimes I have had to drill while at a dull red heat

LOL Hot drilling? really?

If you really want to drill it, Heat it up but don't let it go non magnetic just barely a dull red glow, then let it cool in still air til you can touch it with bare hands NO WATER OR OIL. then drill it.

Note that some steels will air harden in thin sections when the alloys are often thought of as oil hardening. Also thin section steels may not have enough heat for a typical anneal and need a larger "helper bar" also heated up and placed with the original piece into the annealing material to make sure it cools slowly enough. (Knife makers in cold climates learn this one through experience!)

How, exactly did you anneal it?

Trying to drill little holes with a hand drill is tough, if that is wot you are doing,, a drill press is better, a milling maching is tops. AS said above remove scale..some times little rouind stone on a dremel will take the top off the steel where you wish to drill and help you. Carbide bits will drill most anything, you need the steel clamped to another piece of steel when usein carbide or as soon as the cutting edges exit the bit will break. And dont try carbide in a hand held drill. Agin it will break the bit.

If it is oil or water hardened then I would soak at critical and burry it in vermiculite. .

Could you ellaborate as to this process? - sounds very interesting.

LOL funny you say anneal in your first post, but then ask about Ciladog's described process, which happens to be annealing LOL.

My thought exactly!

Now if you are just not familiar with the material mentioned: Vermiculite is often sold at garden centers, it's an expanded mica product used to lighten soil and hold water. For annealing it acts as a good fireproof insulation and we want it DRY DRY DRY---it should be kept dry too!

Other materials used as insulation for annealing are: dry lime powder, Kaowool, dry sifted wood ashes or my favorite---bung the piece into the gas forge at the end of the day, let heat up and then turn off the gas forge and block off the opening to let it cool slowly over night.

In general you would like to stick the piece in the annealing insulation say at 7pm and have it still faintly warm to the touch at 7am. Most times I don't achieve that; but still get a good anneal.

If you have many small items you can sometimes group them together to provide the heat reservoir---I was once consulted on how to anneal some modern made traditional nails being used as rivets on a viking boat project. I stuck them all into a stainless steel creamer in bunches, and stuck the whole thing in the insulative material.

LOL funny you say anneal in your first post, but then ask about Ciladog's described process, which happens to be annealing LOL.

Ive never buryed annything in vermiculate before. thanks for your help on the matter though!

Kendall maybe it would help if you let us know how you annealed the piece you are trying to work with?

My thought exactly!

Now if you are just not familiar with the material mentioned: Vermiculite is often sold at garden centers, it's an expanded mica product used to lighten soil and hold water. For annealing it acts as a good fireproof insulation and we want it DRY DRY DRY---it should be kept dry too!

Other materials used as insulation for annealing are: dry lime powder, Kaowool, dry sifted wood ashes or my favorite---bung the piece into the gas forge at the end of the day, let heat up and then turn off the gas forge and block off the opening to let it cool slowly over night.

In general you would like to stick the piece in the annealing insulation say at 7pm and have it still faintly warm to the touch at 7am. Most times I don't achieve that; but still get a good anneal.

If you have many small items you can sometimes group them together to provide the heat reservoir---I was once consulted on how to anneal some modern made traditional nails being used as rivets on a viking boat project. I stuck them all into a stainless steel creamer in bunches, and stuck the whole thing in the insulative material.

Thankyou for ellaborating on that for me, really helpfull.

Kendall maybe it woul dhelp if you let us know how you annealed the iece you are trying to work with?

I allow the heated item to cool buryed a little in the coke on the forge bed - nearish the fire for warmth but not too close.

Edited June 21, 201213 yr by Kendall P

I allow the heated item to cool buryed a little in the coke on the forge bed - nearish the fire for warmth but not too close.

What heat do you allow it to cool from? Maybe you are not getting it to the right temperature before annealing

What heat do you allow it to cool from? Maybe you are not getting it to the right temperature before annealing

cherry red - but im thinking im not leaving it for long enough - and the vermiculate suggestion sounds like a plan.

sometimes you need to preheat the vermiculite, heat a largeish piece of stock and put that in where you will put your part, leave it for a bit maybe 15-30 min and then either switch it with your part or add your part next to it. Keep vermiculite in a metal can with a lid, like a small trash can of 10 gal size or so.

Is that "Bing cherry red" or "Pie cherry red"? (not the canned stuff but actual pie cherries that are on the tree and are more an orange colour!)

A lot of people get in trouble in blacksmithing as they think of Bing cherries which were not well known when a lot of the smithing books we work from were written. Pie cherry red is much hotter than bing cherry red. Pie cherries were known all over way before the Bing cherry was developed in late 19th century NW America

(See how ridiculous things can get if folks are not sufficiently precise? Or take into account history)

The material you are working with matters as well. I don't recall seeing anyone mention some alloys will form carbides that need either a hotter fire or a soak (or both) to dissolve them. Carbides can be extremely hard and will resist cutting and abrasion.

For relatively simple steels, heat to non-magnetic or a bit more then slow cool by what ever method available allows for slow cooling (I generally have wood ashes on hand but have left a piece sitting on top of a coal fire).

ron

BING GO!!! Thomas You picked a ripe one there! How about them Ranier cherries though? That be really hot metal and better cherries too!

IMHO, If its an old file or basic carbon steel not a new alloy type steel, heat to 20degrees or so above non magnetic right through by allowing a sok time, and then allow to cool as slow as possible

Just as an update - got the vermiculate and heated a chunk of steel to pop in with the knife - annealed perfectly and drilled really easilly, thankyou so much guys :)

Maybe if you had read the post I made that is now a heat treat sticky you would have avoided this entire problem, as well as this thread :)

I have had problems before with files, especially after the vermiculite anneal having hard spots. The best advice i have been given is to spheroid anneal it, heat to non mag then in the dark watch for ALL color to be gone and quench in oil. It really cuts down on "hard spots". ymmv

REally?