What is a good drill bit to use for drilling hardened steel. I'm looking for something I can use repeatedly and something I can pick up at Lowes or Home Depot.
Drill bit for hardened steel
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The HD/Lowes around here have really dropped their tool selection, last I was in there for a metal bit, all they had were those "cone" multi size bits, Freud brand I think? Worked great, but has a limited depth for the size you want
For hardened steel you need a harder bit - carbide. The only downside is that carbide drill bits don't like to flex, they break. So drilling must be done straight & true, with no side load. Here's a good source: McMaster-Carr click on "Straight-Flute Carbide Short-Length Drill Bits for Hard Steel". Warning, these bits are pricey but they'll do the job. We deal with them a lot at work, their delivery is quick.
One thing is for sure, don't break the bit inside the hardened steel.
High speed drills that contain cobalt will take the heat better. Keep it slow and use lots of cutting oil.
Originally Posted By: Rick in PA
For hardened steel you need a harder bit - carbide. The only downside is that carbide drill bits don't like to flex, they break. So drilling must be done straight & true, with no side load. Here's a good source: McMaster-Carr click on "Straight-Flute Carbide Short-Length Drill Bits for Hard Steel". Warning, these bits are pricey but they'll do the job. We deal with them a lot at work, their delivery is quick.
Is this a bit that will drill out a stuck and broken bolt extractor?
For hardened steel you need a harder bit - carbide. The only downside is that carbide drill bits don't like to flex, they break. So drilling must be done straight & true, with no side load. Here's a good source: McMaster-Carr click on "Straight-Flute Carbide Short-Length Drill Bits for Hard Steel". Warning, these bits are pricey but they'll do the job. We deal with them a lot at work, their delivery is quick.
Is this a bit that will drill out a stuck and broken bolt extractor?
Cobalt and use motor oil or cutting fluid.
Originally Posted By: Mr_Incredible
Originally Posted By: Rick in PA
For hardened steel you need a harder bit - carbide. The only downside is that carbide drill bits don't like to flex, they break. So drilling must be done straight & true, with no side load. Here's a good source: McMaster-Carr click on "Straight-Flute Carbide Short-Length Drill Bits for Hard Steel". Warning, these bits are pricey but they'll do the job. We deal with them a lot at work, their delivery is quick.
Is this a bit that will drill out a stuck and broken bolt extractor?
While a carbide bit would be hard enough to drill an extractor, I'd be concerned the bit would catch on the extractor and break. Carbide bits are best used in homogeneous material.
Originally Posted By: Rick in PA
For hardened steel you need a harder bit - carbide. The only downside is that carbide drill bits don't like to flex, they break. So drilling must be done straight & true, with no side load. Here's a good source: McMaster-Carr click on "Straight-Flute Carbide Short-Length Drill Bits for Hard Steel". Warning, these bits are pricey but they'll do the job. We deal with them a lot at work, their delivery is quick.
Is this a bit that will drill out a stuck and broken bolt extractor?
While a carbide bit would be hard enough to drill an extractor, I'd be concerned the bit would catch on the extractor and break. Carbide bits are best used in homogeneous material.
Originally Posted By: Mr_Incredible
Originally Posted By: Rick in PA
For hardened steel you need a harder bit - carbide. The only downside is that carbide drill bits don't like to flex, they break. So drilling must be done straight & true, with no side load. Here's a good source: McMaster-Carr click on "Straight-Flute Carbide Short-Length Drill Bits for Hard Steel". Warning, these bits are pricey but they'll do the job. We deal with them a lot at work, their delivery is quick.
Is this a bit that will drill out a stuck and broken bolt extractor?
Before my dad retired and sold the machine shop they used an electron drill to burn taps and broken easy outs out.
Nice and clean without damaging thew surrounding metal, you can find shops with the equipment to burn it out for you at a reasonable price.
Originally Posted By: Rick in PA
For hardened steel you need a harder bit - carbide. The only downside is that carbide drill bits don't like to flex, they break. So drilling must be done straight & true, with no side load. Here's a good source: McMaster-Carr click on "Straight-Flute Carbide Short-Length Drill Bits for Hard Steel". Warning, these bits are pricey but they'll do the job. We deal with them a lot at work, their delivery is quick.
Is this a bit that will drill out a stuck and broken bolt extractor?
Before my dad retired and sold the machine shop they used an electron drill to burn taps and broken easy outs out.
Nice and clean without damaging thew surrounding metal, you can find shops with the equipment to burn it out for you at a reasonable price.
There is a brand of drill bit called "Rodman". Often sold at shows and so on (but don't be fooled, they are pretty good for hard stuff) . I have both the small set and the larger set. And they are life-savers.
They will drill through files, drill through other drill bits and drill through concrete with rebar, tile, toilet bowls (ha ha) and so on. They are really tough. Plus, if you break one, they will replace it free.
I'm not claiming they are fantastic. They are imprecise and not for everyday use. But, when you need to make more than one hole in something really hard, they are the only easy solution.
They don't need lube and should be used at high speed.
http://www.rodmanandcoinc.com/rodmanandcoinc.com/item04c5-2.html?UCIDs=1
http://www.youtube.com/watch?v=eucK_CtAN1g
They will drill through files, drill through other drill bits and drill through concrete with rebar, tile, toilet bowls (ha ha) and so on. They are really tough. Plus, if you break one, they will replace it free.
I'm not claiming they are fantastic. They are imprecise and not for everyday use. But, when you need to make more than one hole in something really hard, they are the only easy solution.
They don't need lube and should be used at high speed.
http://www.rodmanandcoinc.com/rodmanandcoinc.com/item04c5-2.html?UCIDs=1
http://www.youtube.com/watch?v=eucK_CtAN1g
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What type of machine are you drilling with and what size of drill bit?
Bump!! I found this thread on Google while searching for drill bits.
I'm trying to drill out a broken grease fitting from of a lower control arm ball joint and this grease fitting is laughing at the drill bits I try. The first one was a Morse left-hand rotating high speed steel bit, and the second one was a right hand rotating cobalt DeWalt. This grease fitting must be made out of undrillium.
I'm trying to drill out a broken grease fitting from of a lower control arm ball joint and this grease fitting is laughing at the drill bits I try. The first one was a Morse left-hand rotating high speed steel bit, and the second one was a right hand rotating cobalt DeWalt. This grease fitting must be made out of undrillium.
Is the bit getting hot? Try a lower speed with a brand new bit. I usually start with a 1/8 pilot hole and work my way up by 1/8s in diameter. I bought a 10 pack of 1/8 bits at HF They were titanium tipped or some such. If I was careful, I got some use from them . If I got off angle or pushed, they snapped.
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