Very confused

[Eagle3delta]

I tempered my blade the exact same way I always do and I can’t drill a hole in it. I have never had this problem before.
I’m using 1084 steel that I heated up to non magnetic and quenched. I then tempered at 450 for 2 hours. The blade came out nice straw color just like my other blades.
Any help would be appreciated.
Robert

 

[danbot]

Are you running the drill in reverse?

 

[dirc]

Are you running the drill in reverse?

more likely it's just time to replace the drill bit : ) they do get dull over time, esp. when drilling hardened steel often

 

[Charlie Mike]

Straight flute carbide is what you need.

 

[thebrain]

Perhaps some kind of decarb hard spot happening? If all else is the same.

 

[Eagle3delta]

more likely it's just time to replace the drill bit : ) they do get dull over time, esp. when drilling hardened steel often

I’m not running in reverse and the bits are new.

 

[Mo2]

I'm not a knife maker, but was watching forged in the fire the other week. The guy was drilling too slow and wasn't going anywhere, just making a horrible noise. The judges said it had to be at a faster rpm to get through. Hope it helps if not I dunno. Generally they recommend drilling the holes on the show before heat treatment.

 

[Horsewright]

Drill before ht?

 

[A.McPherson]

Drill before ht?

Winner, winner, chicken dinner!!!

 

[Eagle3delta]

So what is the best bits to buy?

 

[Eagle3delta]

Drill before ht?

I know. Had a major brain fart.

 

[dirc]

for hardened steel, cobalt bits tend to perform the best, or you can get titanium nitride coated bits... either should work well

 

[Drew Riley]

I don't know about anybody else (especially given some of the answers given thus far), but once I harden a blade, I don't expect to be able to drill through it with anything but a carbide bit. Tempering a blade may knock off a couple of points of hardness on the HRC scale, but it by no means makes it soft. If you want to drill after heat treat and temper, you'll need to anneal it, or step up to a carbide or carbide tipped bit.

 

[Horsewright]

Masonry bits will work in a pinch. They're cheap but will get ya through. Might take a couple per hole.

 

[Natlek]

So what is the best bits to buy?

This one , and you can drill in whatever you want ...except diamonds

https://www.bladeforums.com/threads/drilling-hardened-steel-easy-cheap-way.1625415/#post-18570049

 

[007Airman]

I would use diamond bits.

 

[Rhinoknives1]

I have always been happy with Carbide bits. Solid that it. For having to drill a hardened blade tang. I buy them off of eBay .. we are down to one Hardware store in my town and I do better on line for consumables, bits, belts etc

 

[skillgannon]

If you did what I often did with 1084 is harden the blade and leave the handle soft but on a few I hardened much further down the handle then planned. You can try to keep the blade cool while softening the handle by heating. JT a smith here recommends drilling while hot. Or carbide. If you use carbide its higher speed and less pressure and don't let the work move. If you get a hole through those masonry bits will work pretty good too.

 

[Matt Rochester]

So what is the best bits to buy?

https://usaknifemaker.com/drill-bit-carbide-straight-flute.html

Buy 2 in case you break one which is likely while learning. Go slow. Use oil. Have a solid backer for your material as most mine would break right as they started to come through if I didn’t have a backer. I use a 1” thick aluminum plate but mild steel plate will also work. I drill Cpm154 at 61rc frequently.

 

[milkbaby]

Drill before ht?

^This... I always follow a set procedure for every knife that I make. First step is design, then profile, then drilling the holes in the handle. When you follow a set plan, things usually are easier. When you fail to prepare, then you prepare to fail.

Also, I'm surprised nobody commented on how the OP previously drilled through "hardened" steel so easily but has problems now even though he did the same as before. Makes me wonder how successfully hardened the previous ones turned out or whether everything was actually done the same way. Doing the exact same thing should yield the exact same results if the steel was the same batch.