Question about left-handed drill bits

[bbs lm-r]

Please school me on left-handed (reverse) drill bits.

I'm shopping around for some and it looks like you'd want to use them on a drill with a keyed chuck, seeing how to use one you need to drill in reverse and a keyless chuck will just loosen up when it hits resistance in reverse.

What about a keyless chuck that has a ratcheting/locking mechanism? It seems like it would hold but I'm not sure and I can't seem to find a solid answer.

If it helps, this is my current drill http://www.dewalt.com/tools/cordless-drills-drilldrivers-dcd771c2.aspx

 

[MikeF2316]

Please school me on left-handed (reverse) drill bits.

I'm shopping around for some and it looks like you'd want to use them on a drill with a keyed chuck, seeing how to use one you need to drill in reverse and a keyless chuck will just loosen up when it hits resistance in reverse.

What about a keyless chuck that has a locking mechanism? It seems like it would hold but I'm not sure and I can't seem to find a solid answer.

A keyless chuck doesn't loosen when you drill in reverse. It certainly doesn't loosen when you screw in reverse!

 

[91bronc300]

I've never had a problem using left hand drill bits in a keyless chuck.

 

[jakemac]

Does Home depot stock them on the shelves next to the left handed nails ?

 

[bbs lm-r]

ok, looks like I got my answer.

 

[mike13u]

curious, what are you using left handed drill bits for? Broken screw?

 

[Chuck122]

curious, what are you using left handed drill bits for? Broken screw?

Exactly

 

[Mazdaspeed]

They're no different than anything else in the drill when it's in reverse...handy to have them, near impossible to find locally.

 

[larry_g]

The Albrecht chucks will loosen, BTDT. Most of the chucks on hand held drill motors will be OK.

lg
no neat sig line

 

[eric87]

I got a set at hartvill tool. they remove bolts and screws great.

 

[genevabuck]

I just bought some multi splined extractors. Do I need to use left-handed drills with them?

 

[just a noob]

I just bought some multi splined extractors. Do I need to use left-handed drills with them?

Not that I'm aware, but the idea is that the drillbit might "bite" into the screw and back out with the drillbit

 

[Shadowdog500]

+1! The left handed bit is just to back the bolt out if it catches. If I'm dealing with a flush snapped bolt on a frame that I believe is corroded on the exposed threads inside the frame I use a regular bit with the hope that it will catch and drive it out the other side.

Chris

 

[rhuff86]

I am in the market for some too. Hoping my SO driver will let me add the set that is on sale on to my bill. I have heard with these it is best to use an air drill as the electric ones are not built to cool in reverse and will over heat. Any truth to this?

 

[firebox40dash5]

I found out the Rohm Supra self tightening chucks like Dewalt used to use on their heavy dity cordless drill like to loosen in reverse. At least mine sure did... bummer, cuz it was otherwise a sweet chuck.

If you've got siezed threads, lefty bits probably aren't gonna cut it, though with heat and lube it's worth a shot. If the bolt snapped from being overtightened or the shank broke, they do pretty well.

 

[mrtoolfool]

I just used one the other day and it did exactly what it was supposed to do.
It backed the bolt right out that I was drilling.

The bolt I was drilling out was only a quarter inch and wasn't rusted in so it worked well. I imagine that if it is rusted in they may not work that easily.

I bought a set of Hanson bits that came with extractors in an index. I've had them for years but only used them a handful of times. One of those things your glad you have when you need it.

Amazon sells a set similar to what I have.

http://www.amazon.com/Irwin-Industrial-Tools-11119-Extractors/dp/B0002NYBH8/ref=sr_sp-atf_title_1_1?ie=UTF8&qid=1390459385&sr=8-1&keywords=hanson+left+drill+set+11119

 

[mrtoolfool]

If you've got siezed threads, lefty bits probably aren't gonna cut it, though with heat and lube it's worth a shot. If the bolt snapped from being overtightened or the shank broke, they do pretty well.

I agree 100%

 

[lilredex]

If you open the jaws of the chuck, you'll see an Allen head screw at the bottom. That is what stops the chuck from unscrewing when operated in reverse. That screw is also LH threaded.

You can buy LH drill bits individually from KBC (page #9 of cat.).....not cheap, but..

http://www.kbctools.com/can/Navigation/NavPDF.cfm

Edit: LH bits are right on your doorstep.

http://www.harborfreight.com/13-piece-left-hand-drill-bit-set-95146.html

 

[larry_g]

I bought a set of Hanson bits that came with extractors in an index. I've had them for years but only used them a handful of times. One of those things your glad you have when you need it.

Amazon sells a set similar to what I have.

http://www.amazon.com/Irwin-Industrial-Tools-11119-Extractors/dp/B0002NYBH8/ref=sr_sp-atf_title_1_1?ie=UTF8&qid=1390459385&sr=8-1&keywords=hanson+left+drill+set+11119

Guys, If you order one of these Hanson sets be aware that they have different ones with regular drill bits in them also. Make sure that you order the ones with the left had twist if that is what you want. They are a good tool.

lg
no neat sig line

 

[fatfillup]

Cordless chucks are handy but for serious drilling, I prefer a keyed chucked. If there is a chance the bit will catch, I go keyed if I have a choice.