Drill bits-what do you use?

Joined
Oct 18, 2005
Messages
205
Hey guys.

I was wondering what kind of drill bits you use for drilling holes in O1,D2,...

It´s so damn annoying when you drill a few holes and the drill is blunt...

I drill at low speed but my drill get blunt pretty fast

SO I was wondering what kind you use ???

OH and how do you drill 1-2" holes?
do you use a step drill bit???

THANKS
AL
 
Oil
lots of oil
firm pressure
centerpunch, first
I just use sears craftsman brand regular black oxide coated drill bits, nothing fancy lots of oil
I drill while the steel is annealed not after hardening. O-1 has an annoying tendancy to develop flat carbides on the boundary between where it's forged and not, so if I'm going to do a scale tang blade in 0-1 I try to predrill when possible. I got a straight flute carbide drill from Tracey Mickley that's designed for drilling hardened steel to try out next time I play in O-1,

-Page
 
All the bits used on knives in my shop are premium quality.....either cobalt or carbide. The initial price is higher, but they have saved me money because I buy a lot less of them than I would HSS bits. Sizes less than 3/32" are "disposable" in my shop.
One of the best shop tools I've ever gotten is a Drill Doctor bit sharpener. My wife got one for me as a Christmas gift several years ago, and I am now on my third one.......I would estimate that the Drill Doctor has easily saved me $1,000+ over the years its been in the shop. The machine lets you choose the type of point to put on any bit, and grinds "split points" too.

A lot of folks talk about sharpening drill bits freehand on the grinder, but for me thats always been hit-n-miss, but with the Drill Doctor its right every time.
 
For pins and pilot holes I buy the ten pack of 1/8" titanium nitride bits from Harbor Freight for $2.50 not on sale. I can get maybe 15-30 holes out of each one. I use the Drill Doctor for bigger bits and sometimes the HF bits if I have one sitting nearby when I'm sharpening other bits.

I live over 30 minutes from any sort of hardware store so I buy several packs at a time. That's also why I broke down and bought the Drill Doctor. It's not just $5-12 bucks for bigger bits, it's an hour drive plus time in the store plus what I spend on stuff I didn't really need at the store and about $8 gas, $15 if I take the truck... or the project's on hold till I can get to the store :grumpy:

I mostly drill in O1 by the way, but since I got the welder I'm drilling into bed frames and junk metal like that sometimes. I need to soften the bed frames first.

1-2" holes are way out of range of any equipment I have. If you meant 1/2", I go through different sized bits till I get there. That's getting old though so I'll be getting step bits soon.

HF bits:
http://www.harborfreight.com/cpi/ctaf/displayitem.taf?Itemnumber=93079
 
For cheap bits,i prefere the cheapest black oxide coated HSS bits.i find they re sharpen very nicely in the drill doc and work well.the TIN coated or TILAN coated bits for some reason will not resharpen??? then theres carbide..,the best!
 
I use TiNi coated HSS bits for the most part. There is a brand called Norseman that has one of the toughest, sharpest, longest lasting drill bits I've ever used, although I'm not sure which type it is. The Fastenal store near me carries them, and they are a bit pricey, but they do sell them individually...so instead of buying the whole set for $150 you can just pick up mutiples of the most common sizes that you use. IIRC they were about $2- $2.50 a piece, depending upon size. The Fastenal guy said they were the best they had, and I haven't been disappointed yet, and knife steel isn't the only thing they get used on. Good stuff pays for itself in the long run. -Matt-
 
Well, I just use the cheapo bits. I also buy the harbor freight 1/8" bits, but I buy the 36 pack of double ended bits. 72 drills for a couple bucks, so I can afford to toss them if they aren't sharp, or if I'm just angry.

I like regular old M2 bits the best, I find they are the sharpest drill bits new. Even sharper than cobalt, although they don't last as long. Carbide drills like non-other, really sweet, but it's expensive if you make a mistake with it.
 
I have a Drill Doctor but it is still hit-n-miss for me with it. :(

Pad
I have a Drill Doctor, and if used carefully it sharpens perfectly anything 3/32 -1/2 inch sharper and truer than factory
saved me hundreds of dollars (not to mention time when that 13/64ths bit broke at 2 in the morning and I could just resharpen the stub and keep working

-Page
 
I have an old cheapo Black & Decker bit sharpener, it has saved me a bundle and many trips to the hardware store, I think it was only $2 from a garage sale but hey, it works great.
 
I notices that there are several models of Drill doctor. Any preference on the model?
For some reason I don't have much problem drilling tool steel but the Square pipe I picked up to make a NWG is killing bits.
 
I wanna get a drill doctor one of these days. sounds like a nice christmas present.

I use plain jane drill bits to drill D2 and CPM154. I go slow, and use a lot of rapid tap. My bits are not dull yet.
 
You guys are GREAT!
THANKS

Will try to get some of the drill bits you suggested

Hopefully I´ll find a shop who ships overseas.

AL
 
I don't ever experience these problems people report drilling holes in tool steel. It is just not that friggen bad folks. It's annealed! Drill the hole!

I think there are probably three things going on here:

1: letting the bit get really hot, then possibly shocking it with coolant. Flood coolant really helps, but otherwise wet the area and peck frequently enough to let coolant into the cut before the cutter gets too hot.

2: work hardening. Lean into that bit, show it no mercy! Just let off some as the web exits so you don't over feed and ruin the corners. Many steels we work with will work harden if the bit isn't fed hard enough to cut. Also, there are carbides suspended in the steel that you need to get through. If you let it rub, those carbides will dull your bit.

3: play or flexibility in your setup can allow uneven chip loads or chatter as things move around. That will dull a bit.

Cobalt HSS bits do last longer in abrasive applications, and steel with carbides in it are abrasive. I've never done a measured test, but I would expect an American HSS drill bit to drill a few hundred holes in 1/8" D2 before giving up and cobalt HSS perhaps 50% more. Any drill you're likely to come across should be up to the task of drilling a few holes in spheroid annealed steel without problem. Using an appropriate spindle speed, feed and coolant, most any bit should work. Lubrication should be unnecessary in such a shallow hole, but certainly won't hurt.

Larger holes can be done with hole saws. It can also be done with a trepanning cutter. I use circular interpolation...
 
I switched over to masonry bits with the carbide tips. They work but are limited in size.

Once I discovered cutting and tapping fluid, it really didn't matter what type of bit I used. The drill bit just had to be sharp or new.

I start a shallow hole and then add plenty of fluid. Peck away and add a drop or two every peck.
 
I notices that there are several models of Drill doctor. Any preference on the model?
For some reason I don't have much problem drilling tool steel but the Square pipe I picked up to make a NWG is killing bits.

Oh crap... so square pipe is hard to drill? I want to make a NWG myself and I will be facing that very same problem soon. It is mild steel... it shouldn't harden in any way! I will let you know...

Mikel
 
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