left hand drill bits

[CGC4200]

Anybody use these for drilling out broken bolts in chainsaws or other
equipment? Supposedly, the broken bolt will come out sometimes without
use of an easy out or another type screw extractor.

 

[jrr344]

Anybody use these for drilling out broken bolts in chainsaws or other
equipment? Supposedly, the broken bolt will come out sometimes without
use of an easy out or another type screw extractor.

I have, sometimes they work great, but if it is really in there they won't work, but it will work on a normal broken bolt.

 

[pioneerguy600]

You got it, if the broke off bolt is not rusted/seized in the threads it will sometimes back out.
Pioneerguy600

 

[John R]

I've had good luck with them, but like others have said if the bolt is really stuck it's a no go.
But you still have the hole you need to try something else.

 

[barneyrb]

Like others have said, it will work unless rusted or siezed up. I may also add that if the drill won't get it out an ease-out will usually have serious problems or even not work.

 

[ScottWojo]

Do this.

This trick works spectacularly.

Steel bolt broke flush in aluminum? lay a nut over the broken bolt then fill the nut with the mig welder. Let it sit for a minute, then put a wrench on the nut and back it out.

It works on the toughest bolts. Even broken exhaust studs in aluminum heads.

 

[Eric Modell]

We use them all the time at work. It is always a good way to start to remove a broken bolt.

 

[swerner]

Make sure it is on center. Take YOUR time to do this. If its above flush, grind it flat and center punch it. If you have access to a drill press it will make the job easier. If the left hand bit fails to bring it out, at least you will be one center to then drill it out to the tap drill size. I've had a lot of luck with that method. Once the meat is gone so is the pressure and even if it is rusted you have a chance with an easy out. However, I would still soak the bolt/stud. Good Luck!

Oh yeah, heat can be your friend! Multiple heat cycles can sometimes break up the rust due to the expansion and contraction.

 

[promac850]

This trick works spectacularly.

Steel bolt broke flush in aluminum? lay a nut over the broken bolt then fill the nut with the mig welder. Let it sit for a minute, then put a wrench on the nut and back it out.

It works on the toughest bolts. Even broken exhaust studs in aluminum heads.

Great! Will have to remember that if I ever encounter a flush broken bolt again! Spent money on a MIG welder, and found another use for it.

 

[Blowncrewcab]

I use left hand bits all the time, the trick is to go slooooooooooooowwwww, the slower the better, this gives it a chance to get a good bite and turn the bolt instead of drilling into it. the sharper the bit the better & the more aggressive the cut on the bit the better. Push hard and go slow. Some PB Blaster will help if it has corroded threads.

 

[Labman]

Naw, a dull bit produces more heat and vibration.

Real mechanics apply the heat and vibration before bolt breaks off.

A long time ago, I was trying to buy some aircraft length drill bits. Milwalkee was out. They told my main man that they had moved their factory to Kentucky. Their new help were producing left had drill bits. He told them fine, we have a reversible drill. He was from Tennessee, and it was days until he quit laughing enough that I was able to get any work out of him.

 

[heimannm]

If I recall, I ordered my left hand drill bits from McMaster Carr. I don't have to use them often but when the need arises they can get you out of a trouble spot.

For smaller screws it may be the only option as it can be hard to weld a nut to a 4 mm fastener.

Mark

 

[kevin j]

Also helps to start quite smal, then move up a couple sizes at a time and keep drilling. As it removes metal from the center it sometimes releives the pressure outward. Thyen the next larger size tens to 'snag' and back out the slug.
and heat, of course, if possible.

 

[Bret4207]

Had a real nice set some years back that disappeared. But I found a set at Habor Freight of all places that seem to work okay.

For little stuck screws that an EZ out won't work on try a Torx bit. They seem to work better than most EZ outs. Just drill an appropriate sized hole and drive the torx bit in. They seem to work pretty good, don't break easily and don't wedge themselves into the work like a screw type EZ out.

 

[djones]

if the bolt is a through bolt it is also possible to right hand drill straight through. Somtimes the bolt will be forced out in that direction. BP Blaster to the rescue.

 

[gallegosmike]

Bolt removal kit from harbor freight worked wonders for me when the gold colored muffler bolts on my husky 346xp-ne came seized from the factory.

My .02

Mike

 

[54stude]

For small broken off studs like 4mm and 8-32, I usually weld a small fender washer to the stud with a mig tack weld, and then weld a nut to that washer. If you "miss" with the tack, just remove the washer and try again. This way is easier than welding the stud into the hole and creating a mess.

 

[Labman]

Had a real nice set some years back that disappeared. But I found a set at Habor Freight of all places that seem to work okay.

For little stuck screws that an EZ out won't work on try a Torx bit. They seem to work better than most EZ outs. Just drill an appropriate sized hole and drive the torx bit in. They seem to work pretty good, don't break easily and don't wedge themselves into the work like a screw type EZ out.

The one shop I worked in had a set of similar looking things made for the job.

 

[MO-Iron]

I just take an old right handed drill bit and sharpen it to cut backwards. The right handed flutes will drive the shavings down into the hole and pack tight. The shavings will increase the chance of the bit hanging and bringing the bolt out. To sharpen the bit backwards, I usually use an air cutoff tool to cut the bit off square. It's awkward to remember to angle the rear of the bit to the right instead of the left when sharpening, but with a little practice it's just as easy as normal freehand sharpening. Next time I am at the shop, I will snap a picture for an example.

MO-Iron

 

[maico490]

For small broken off studs like 4mm and 8-32, I usually weld a small fender washer to the stud with a mig tack weld, and then weld a nut to that washer. If you "miss" with the tack, just remove the washer and try again. This way is easier than welding the stud into the hole and creating a mess.

As with the earlier post on welding a nut on, this is the way to do it.