Drill bits

[He Man]

Cant seem to really find the answer anywhere, but if you wanted strong bits for drilling into metal such as bolts.

Whats the best kind of bit to go with? There are cobolt ones and High Speed Steel. Are they just coated in cobolt like the ttitanium coated ones? or is it an alloy?

Im looking to pick up a set of Left handed drill bits and put together a bolt extractor kit.

On another note, i also managed to break an extractor trying to get a bolt out. Whats the best way to get the extractor out? In the end i managed to get a nice bite on it, and spun it loose then picked it out with a file. Never want to go through that again.

[WarrenJ]

I've had real good luck with the Milwaukee brand Cobalt bits for drilling hardened steel.  I make custom knives and sometimes need to drill heat treated tool steel.  Highspeed steel bits and Titanium Nitride bits just skate around on the blade but those Milwaukee Cobalts punch through like I'm drilling angle iron.  Other cobalt brands may be just as good or better but I don't have any first hand experience with them to comment.

[ducpainter]

I think most of the coated bits are gimmicky. Never used any cobalt bits. Get some good bits and a sharpener like the 'Drill Doctor'. Sharp bits will drill your hardware.

About the extractor removal...you got lucky. There's no good way. I've seen expensive EDM machines ruin a part.

[He Man]

thats not a good thing to hear i got lucky, because i can only inmagine how bad it can get.

I think the coatings are BS too. Thats why im wondering if cobalt bits are coatings or alloys. If its a coating i could care less because when i sharpen the edge the coatings gone so whats the point?

So I guess High Speed steel is the prefered choice?

theres also Carbide tipped. They say thats good for hardened steel, so good for getting out bolt extractors if they break?

[ducpainter]

thats not a good thing to hear i got lucky, because i can only inmagine how bad it can get.

I think the coatings are BS too. Thats why im wondering if cobalt bits are coatings or alloys. If its a coating i could care less because when i sharpen the edge the coatings gone so whats the point?

So I guess High Speed steel is the prefered choice?

theres also Carbide tipped. They say thats good for hardened steel, so good for getting out bolt extractors if they break?

A carbide bit would be the only thing I can think of that might work. Extractors are really hard...and brittle as you discovered

[NoisyDante]

I broke off an extractor bit in one of the bolts holding the handlebar clamp on.  It was in really good too, no possibility of getting it out, and it was positioned in such a way that getting a drill bit in there wasn't happening.  I finally pounded in a hex bit with a hammer, what a PITA that was.

[mitt]

High speed steel is good.  Carbide is better.  The coated ones I also agree with are a gimmick.

mitt

[Vindingo]

Find a machine shop or metal shop that makes their own bits, and as ducpainter said, get a bit sharpener.  

Cobalt drill bits are not a coating.  When doing a big project with stainless, we used them instead of HSS.  Im going to +3 on those TiNi coated bits being crap.  Most big brand name bits you are going to get at HD or Lowes will be crap, get dull really fast or break.  

If you can't find a machine shop that makes bits, ask them where they get theirs.    

[Speedbag]

Solid carbide. 

[il d00d]

Whats the best way to get the extractor out?

If you aspire to internet infamy, then sawzall.  Definitely that.

[He Man]

Solid carbide. 

holy crap that stuff aint cheap!

What kinda sizes do you guys recommend? Im thinking a few 1/8th, 3/16 and 5/16 left handed jabbers to drill the hole and a #1 and a #2 extractor to match.

and 2 carbide tipped ones in case shit hits the fan. oh and a butane pen torch. :p

If you aspire to internet infamy, then sawzall.  Definitely that.

The bolts stuck on the front of the frame... so you want me to cut the frame in half? 

[Speeddog]

If you're drilling freehand, don't bother getting solid carbide drills, you'll just break 'em.

[Popeye the Sailor]

Why are you drilling out bolts to begin with? How many bolts you rounding off? 

[He Man]

yea i broke a HSS 1/8bit already.

MrI i aint rounding anything its for the "oh shit the bolt head snapped off!" situations where i want to be able to whip out a kit instead of improvising and wasting time traveling to the store to get the right shit. next thing you know its 5pm and somehow your drunk and nothings been done cause you took a trip to home depot but ended up at beer depot.

[Popeye the Sailor]

Meh.  Use more penetrating oil and less force.