Drilling Through Normalized(?) O1 Tool Steel

The shop lighting was in between. I know it definitely was hotter than a red.

I actually asked the local metal supermarket for W1 but they said only placed two orders in the last 20 years so they don't bother stocking it. Also, it only comes in drill rods so any blade would need to be forged or at least flattened out before hand profiling.

My only source for local quality high carbon steel would be Nicholson files but at around $12 per 10 inch bastard file, it's a bit pricey.
 
duurza said:
Thank you for all of your responses. I don't have access to a drill press right now so if I absolutely need one, I might need to put this on hold. I will look for some carbide/cobalt drill bits and honestly, if they cost less than $10 each, I'll give it a shot.

As for putting heat into the blade, I'm not worried, I just don't have a blow torch. The sword blade is 28 inches and the tang is around 9 inches total and I would be drilling a hole literally within the first quarter inch of the pommel end of the tang.

Although I don't think tempering it would soften it by much, I'll give it a try tonight and see how it goes.
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Don't know how good they are but I just ordered a carbide bit and a carbide reamer from here:

http://aeroprotechinc.com/50-straight-flute-drills#/

I'm planning on using these for much harder and much, much more wear resistant steel than O1. If they do well I'm probably gonna order more. Depending on the size you need they're around the price you said.

Much cheaper than the knife supply websites I looked at and there's much more info about them which is a good sign.
 
Quick Update: So it seems I figured out what was wrong. I was cooking something on the pan earlier and decided to put the tang between the pan and the element to temper a bit (I got impatient). Afterwards, I could drill a bit deeper into it. I'm going to guess that when it was cooling from above the critical temperature, the surface cooled past the Ms and it hardened. Since the temperature gradient is moving from core to surface, the heat from the core tempered the surface but there wasn't enough heat to temper the core much so that stayed relatively hard.

Just so glad I never dropped the tang. Anyway, I'm gradually tempering it and continuing to drill through. Thanks for all of your help!
 
bodog said:
Don't know how good they are but I just ordered a carbide bit and a carbide reamer from here:

http://aeroprotechinc.com/50-straight-flute-drills#/

I'm planning on using these for much harder and much, much more wear resistant steel than O1. If they do well I'm probably gonna order more. Depending on the size you need they're around the price you said.

Much cheaper than the knife supply websites I looked at and there's much more info about them which is a good sign.
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So just used this .250" carbide drill bit on some hardened k390 San mai with the core at 63 RC. Went through like a champ using tap magic cutting oil. Nowhere near the pain I thought it was going to be. My HSS TiN coated bits didn't want to cut even the outer layer.

It cut through just about like a regular drill bit would cut through wood. Coated the bit with the oil, ran at about 800 rpm, added oil three times during the cut to be sure I didn't screw it up, and went through no problem. Once the bit started pushing through I made sure to add a little more oil and went a little slower. I was expecting the bit to shatter. I had safety glasses on and was waiting to be sprayed with broken metal and whatnot. Didn't happen.

Wasn't quite like cutting through butter but it wasn't that far off.
 
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Nick, the 1/4" bit I just used was about 17 bucks. That's about the diameter where they start jumping in price. Most of the smaller ones are 10 bucks or less.

I also ordered a small reamer that costs like 13 bucks. They sent a considerably larger one that costs 70 bucks on their site. I could go into the house and look but if I remember right it was a 25/64" reamer. I contacted them to let them know I'd return it if they sent a shipping label and they said keep the big reamer and they'd send the right one ASAP via priority mail. Pretty good service. No hassles.
 
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