removing broken bolts & studs

[rphillips]

When drilling broken bolts or studs, use a left hand drill. Many times the heat, vibration, & the drill turning backwards will snag the broken part & spin it out. If it doesn't, you still have a hole, exactly like the hole you would have had with a right hand drill. The extractor, or EZ out, doesn't care if the hole was drilled lefty or righty.

 

[Zooks]

I have enever even heard of a left hand drill???

Is that like a left handed screwdriver or a tin of striped paint???? LOL

 

[Junkie]

They certainly exist. You know how normal drill bits are designed for being used clockwise? Well left handed drill bits are deisgned for being used counterclockwise. Most drills will do either direction.

I ouoght to pick some up, I need to get some broken bolts out of my case.

 

[80-81, GS 1100]

Sounds like a good idea. Wonder how much
a left hand drill costs? Is it much more cause
its rare?

 

[rphillips]

You probably won't find them at Wal-Mart, but they aren't that hard to find. Harbor Freight, Grainger, MSC industrial supply, Fastenal, I've not looked, but I'd bet Craftsman has them. Maybe not in stock in all stores, but I'll bet they could get them for you within a few days. They aren't that rare, you just see the right handed first & don't think about the left handed ones. The prices are slightly higher, not double nor nothing like that, maybe a couple $ per set. Like I said, they won't always get your broken screw out, but if it doesn't, you still have a round hole that is the same as you would have had with a right hand drill.

 

[tkent02]

The lefty bit works more often than you might imagine.

 

[PAULYBOY]

Come on you guys. Almost any drill sold now is reversible. Cordless or electris. Left hand drill bits have been around for a hundred years. I'm a lefty and I can't even find out why, though! Seriously, I have 5 drill and 1 cordless impact drill, mostly for my furniture shop, and they all spin both ways. You can get cheap ones that are light duty and will last for 5 or 6 years with reasonable care, or you can get a Makita or DeWalt for ten times the price. Up to you.

 

[USMC_SGT]

Left hand drill bits and my $19.00 black and deckar has saved more than one time. Harder to find left hand drill bits that a reversible drill.

 

[lurch12_2000]

Clarification?
OK, we know there are plenty of reversable drills on the market and most drills now are also variable speed to slowly control the drilling process to extract the broken stud, but the question is about left hand drill BITS and finding them.
But if I have a left hand drill bit I should still be using the forward rotation when drilling because of how the cutting edge/angle of the bit is and it will draw up on the broken stud, correct?
And I don't want to use a regular bit in the drill in reverse because it's cutting edge will not bite into the metal, correct?

 

[rphillips]

Sorry I made this so confusing. I grew up calling the thing with the motor a "drill", but since I've mostly heard them called "drill motors". The thing that does the cutting, we always called "bits", but now I see & hear them called "twist drills". From now on, it'll be "drills" & "bits". A regular, (right hand), bit cuts turning clockwise, a left hand bit cuts turning counter clockwise. Use a "drill", in the reverse (counterclockwise) position with a left hand "bit" to drill the broken bolt. The bit is turning counter clockwise, trying to back the broken bolt out anyway. If the heat & vibration of the "bit" slightly loosens the bolt & the bit hangs slightly, the drill, turning backwards, counter clockwise, will sometimes screw the broken bolt right out.

 

[RJz1100E]

Yep, I've had left hand bits work for me a few times at my place of employment. A lot of the bolts I deal with there are grade 8 and used to bolt stainless plates together, heat torqued to up to 320 ft lbs.

 

[Junkie]

Clarification?
OK, we know there are plenty of reversable drills on the market and most drills now are also variable speed to slowly control the drilling process to extract the broken stud, but the question is about left hand drill BITS and finding them.
But if I have a left hand drill bit I should still be using the forward rotation when drilling because of how the cutting edge/angle of the bit is and it will draw up on the broken stud, correct?
And I don't want to use a regular bit in the drill in reverse because it's cutting edge will not bite into the metal, correct?

With a left handed bit, you want to be using the drill in the opposite direction as with a standard bit. In other words, if it were a screwdriver you would be removing the screw, not putting it in.

 

[gaillarry]

Has anyone tried those " Grab-it" bits sold by Sears and HD?