Helle Temagami overheated by drilling?

S

Spela

Joined
Mar 16, 2014
Messages
44
Hello everyone,
As you can already see, I am very new to this forum and because of that I would like to kindly as you to overlook my possible mistakes when it comes to putting a question into a ''right'' and ''appropriate'' thread. The thing is that I only need help, but don't know who would be the right to answer my question and help me.
So after, I have read many posts and spent quite a fair amount of time on this forum, I have decided that there are many members on this forum, with amazing amounts of experience and amazing amount of knowledge, so I decided to join and ask you all a question.
A while ago I bought a Helle Temagami blank blade. When I got it, I decided to widden the center hole on the tang (the middle hole) from 5mm to 6mm. I also bought drills for INOX and stainless steel, but when I started the process of drilling, I soon found out that those drills are certainly not ment to be drilled into inox or stainless. The tip of the drill got all warped, kind of almost melted, grinded off....in shock and panicking, I thought to myself(I don't know why) that additional pressure will do the job....well, it didn't.... When I started to press the drill harder, the tip of the drill got red hot and also the area around the tang hole(about 2 or 3mm diameter around the hole got dark red) got dark red. After a couple of tries and after a couple of ''heatings'' from the drilling, I stopped.
The question that is bugging me ever since is: is it possible that the heat provided by the unsuccessfull drilling process ruined the famous laminated stainless steel? Is it possible that the heat spreaded from the center hole of the tang all the way up to the blade and ruined it?
When I touched the blade, after heating the area around the hole that much, it was still ''touch-possible'' hot and not so hot that I couldn't have touched it. But anyway, have I ruined the characteristics of the laminated stainless steel? What is the aftermath of that ''thoughtless'' deed?

Thank you so much for answering. I hope that my blade's steel is not ruined.

Best, Vito
 
It's most likely not ruined. When drilling things like that, run the drill as slowly as possible with moderate pressure and be patient
For any future questions of this kind, knifemakers shop talk sub forum is better place for that
 
I'm sure it's fine but upsizing the hole is pretty much out the window now unless you try a carbide burr or something... you work hardened it.
The blade would have to get a lot hotter than still-touchable to hurt the temper.
 
The bolded part below doesn't sound promising.

Spela said:
When I started to press the drill harder, the tip of the drill got red hot and also the area around the tang hole(about 2 or 3mm diameter around the hole got dark red) got dark red. After a couple of tries and after a couple of ''heatings'' from the drilling, I stopped.
Click to expand...
I agree with sparrow and Kevin.
A question for a metallurgist/steel expert.

Doug
 
I would say that if it's just the tang that got hot you will be totally fine. If you could still touch the blade then The temper will be unaffected. You would need temps in the blade of 350 plus, and you certainly wouldn't hold onto that. The centre hole is quite far from the blade so the edge shouldn't have gotten very hot. Also those drills for stainless are not for hardened stainless most likely. They are probably for annealed stainless. If you used a carbide bit the first time it probably would have done alright.
 
Think about a restaurant kitchen, all those stainless cabinets and surfaces, that's what those bits are made for.
 
Stainless kitchen surfaces are made from 300 series SS which is non hardenable. Knife blades are made from 400 series SS which is hardenable. 400 serires parts are usually drilled, milled, tapped, filed, etc. before they are hardened. After hardening, the parts can be ground.
 
I am guessing the blade was already hardened and sharp.A standard drill bit won't touch hardened steel.
 
Work hardened steel is almost hopeless to drill. Best fix is to use your Dremel with abrasive burr to open the to dimension .You might temper at 350 F just in case .You probably haven't damaged the blade itself. There are no great forces in the middle of the tang so no worry about what structure you have.Next time carbide cutter and proper ube !
 
drilling fully hardened stainless absolutely requires a carbide drill. Drilling semi-hardened stainless can be done, but your best bet is with (if not carbide) a cobalt bit. Also, always use coolant. Personally, I favor TapMagic
 
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