reuse big drill bit

Hi. I recently bought a big old toolbox full of junk tools because I
needed the toolbox and also it had a nice V-swage for a post vise in
it. While going through the contents to sort them out, I found a large
drill bit (about 5/8") with a funny sharp point on it. Probably for
brass. It was pretty mangled, and I was wondering if it could be used
for anything.
A spark test showed that it was not a simple high carbon steel. The
spark shower was small in volume and the lines were numerous and thin.
Near where they started, they were red. This looks like high speed
steel. Can this drill be untwisted into a hot work tool? It is
probably air hardening, but may not be all that shock resistant. Or
should I just trash it? It has a weird shank that will not fit in a
taper or Jacob drill chuck.
Some time ago, I recall a post talking about high speed steel forging,
but could not find it. I think that Alvin (from AZ) knows something
about this topic.
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Cool, got a picture? :)
Sounds right so far. :)
Spark testing it, side by side, with a "known sample" is about as good as it gets. How do the sparks look compared to a regular twist drill? (twist drills are mostly M4 anymore and the cobalt ones are mostly M42)
I recently got some A2 drill rod and found out the sparks look the same as O1 except for the color, A2 is a little less reddish orange, more yellow.
Since you are asking about hot work tooling, yes. :) Since you are talking about un-twisting it... Sounds like a nightmare to me but I don't know nuthin'bout that. :/
For "hot work" uses it might be worth messing with, but for others prob'ly no.
If it's high speed steel it might not be worth all that much when you're done. ;) Being a high alloy steel it'll be real easy to screw it up, but if you want to try, go for it and tell us what happened "we're all ears". :)
A guy can blacksmith-heat-treat stuff like A2 and M2 but the results won't be any better (for most things) than if you just started out with O1 or used automotive suspension and steering parts. To get the extra that the medium and high alloy steels have to offer takes fancy heat treating. (other than for heat resisting properties)
H11 and H13 seems to be pretty easy to get and they are sometimes refered to as "semi high speed steel".
Even a "crappy;)" blacksmith style heat treating on H13, M2 (etc) on those type steels can do things when it comes to heat resisting that O1 (etc) can't. Even S5 and S7 have been bragged-on here for hot work too and that was blacksmith style heat treated.
What sort of shank is that?
Sounds like the previous owner didn't know what to do with it either. ;)
If it was some sort of special tooling maybe it's worth more being closer to as-it-is? Just modified enough to put it back to work doing what it was designed for?
Alvin in AZ
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I just loaded one on yahoo:
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I hope this is accessible to the outside. Note that the shank is tapered and square in cross section. There are two holes through it. ...
Yeah, I have read that high speed steel is difficult to forge. It needs to be worked at yellow, but not allowed to get too hot or cold. Stop at orange. I do not have a power hammer, but I do have access to a huge striker with a 10 lb sledge and a 400 lb block anvil.
I have read that most of these strange drill bits are just scrap value, especially when mangled. It seems that they do not sell for much on ebay.
Thanks for the comments. I think that I will try it out. A comparable sized piece of H-13 from the blacksmith suppliers costs about $20.
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The holes are, IMHO, someone's addition. I have several drills of this shape (no holes), and the "drill press" to drive them. It is marked:
The working end of the thing is a square taper socket (but not like a brace - no "holding" of any sort). I think this might be like some post drills, but I haven't see a post drill for years, so perhaps it isn't.
The square taper socket is in a ratcheting part, which ratchets CW only, though the pawls can be disengaged by hand to allow it to move in either direction. There are two ratchet gears and two pawls (one on either side of the handle) which are out of phase, so one will always catch. The ratchet handle is over a foot long.
On the back side there is a long hex section, which unscrews at a rather rapid rate for quite some distance. The far end of this is a cone center (90 degree, I think) - presumably the function of this part is to advance the drill into the work (apply feed pressure). As it unscrews it exposes a smooth machined shaft (the threads are hidden); this would (I guess) reduce wobble as compared to a simple threaded section.
I'm forced into assuming that one arranged a plate with a hole in it or something to be fixed or tied in place to seat the center point in, as I have yet to find an illustration or instructions on this type of portable drill (being elderly and perhaps esoteric). I'm guessing a millwrights tool, as the drill bits are mostly large, and I envision the thing being chained to some big piece of machinery that would be inconvenient/impossible to haul into a shop.
If anyone has more information on this type of "drill press" and it's proper use, I'd love to hear it.
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