Broken bolt with a stud extractor bit stuck in it!

[Alx]

Hi guys,

Here's the deal. I've got a flush sitting broken M8 bolt that I carefully bored with a 3mm drill bit. I then used a stud extractor which unfortunately broke off as well, filling the hole flush! The stud extractor bit is hardened apparently so my further drilling is completely unsuccessful. In the hindsight I should have kept drilling a bigger bore but oh, well.

Any idea what to do next?

Thanks.

 

[Wrenches of Death]

Any idea what to do next?

If you have the equipment, skills, and clearance, how about a nut centered over and welded to the broken bolt and extractor?

I've done this in the past on I don't know how many occasions with a pretty decent success rate..

I've also annealed broken extractors before so that I could drill them out.

WoD

 

[Alx]

Sorry, I don't own a welder and the space is pretty tight. It's an automatic tailgate open/close system that sheared the bolt holding the strut. The bolt is a tad below the surface (a mil or two), so not 100% flush. Any magical drill bits out there that can drill through hardened metal?


EDIT: Are Carbide drill bits any good for this?

 

[TwoInch]

you will probably need to get some carbide bits. and a dremel or other rotary tools and sit infront of that broken bolt for a while and have at it. broken extractors are not fun.

 

[1320stang]

Is it in a vehicle or on your bench?

Some machine shops can burn it out with a EDM.

 

[mayday0017]

This is why I never use any form of "ez out" I have found over the years that odds are they will do more harm then good. Never actually had one remove anything I needed only had them not work at all or break off and cause more of a mess..... If it needs and extractor tool I just go ahead and start drilling.....

Good luck man, it can be done just takes a little while and gets old fast....

 

[Scout Driver]

At this point, it will probably save some aggravation by taking it to someone who can weld a nut onto the offending bolt and extractor.

Not being critical, but it usually works better to drill out a larger hole before trying an extractor. The bolt gets a little more "pliable" and willing to unlock itself from the threads. Usually the extractor doesn't need to be driven in as hard either. An extractor that has been hammered in too hard will actually seize the bolt tighter in the bore.

I've had good results by boring into broken bolts with left-handed bits. They will usually "grab" eventually and spin the bolt out.

Scott

 

[TwoInch]

also, get a set of good left handed drill bits. they are worth their weight in gold in many instances. they usually will spin the broken bolt out themselves, and if they dont, you already have the hole drilled for other attempts. a set of straight flute extractors are a good buy also, seems lots of guys prefer them over spiral fluted designs.

 

[Bill R.]

If its a really hard extractor i would try to shatter it first using a set of those cheap harbor freight transfer punches as the drift, your hole is just under 1/8 inch so i wouldn't mind sacrificing a few to try and shatter it first , if thats not possible then i would try to anneal with a torch as others mentioned... otherwise get the foredom out with some stones and carefully grind it away. We used to use an edm on some but you had to be able to build a clay dam around the area and fill with fluid for the submerged edm to work properly but that was many years ago, i'm certain that machine shops now have much more advanced edm capabilities now.

 

[mayday0017]

Last job our EDM guy could work some amazing tasks.. seen him save $100,000+ parts for flow meters that we thought were going to be scrapped for sure

 

[2oolhound]

When i was driving my 54 power wagon from Vancouver to Prince George a fan blade broke off the fan when i grabbed 3rd gear going up Jackass Pass in the rocky mountains. The blade went through the hood and put the fan off balance which then caused the water pump to separate from the block and fly off through the rad. Being in the middle of of a 500 mile trip I was desperate and used a cutting torch to burn the broken studs out of the engine block. I then ran a tap through the holes and was good to go. I was surprised how well the cutting torch worked. The heat stayed concentrated on the broken bolts and didn't transfer into the block very fast so when I hit the oxy it blew the molten bolt out without hardly damaging the threads in the block. The holes in the block that the water pump mounted to were blind holes too so the molten metal had to come back out the front.

You could try this as a last resort.

 

[TwoInch]

When i was driving my 54 power wagon from Vancouver to Prince George a fan blade broke off the fan when i grabbed 3rd gear going up Jackass Pass in the rocky mountains. The blade went through the hood and put the fan off balance which then caused the water pump to separate from the block and fly off through the rad. Being in the middle of of a 500 mile trip I was desperate and used a cutting torch to burn the broken studs out of the engine block. I then ran a tap through the holes and was good to go. I was surprised how well the cutting torch worked. The heat stayed concentrated on the broken bolts and didn't transfer into the block very fast so when I hit the oxy it blew the molten bolt out without hardly damaging the threads in the block. The holes in the block that the water pump mounted to were blind holes too so the molten metal had to come back out the front.

You could try this as a last resort.

blowing a steel bolt out of cast iron block seems like a sketchy manuever. even though the cast iron is let likely to be mangled if done right. im assuming his situation is not a steel bolt in cast iron part though, more likely to blow out the surrounding area some.

 

[wanted01]

First of all, try using a GOOD quality cobalt drill bit ..., not one of those shiny blue cobalt coated POS, but the real thing. Turn it slow using penetrating oil for lube. That will usually cut through. If that works, then get yourself a straight cut extractor ... Not spiral type and head off to the dollar store and get some birthday candles. The cheap ones work better due to higher wax content. Now if you heat the broken bolt until red hot, then place the candle on it, the candle will melt and wick the wax through the threads adding a lube to the threads to help get it moving and not seize up once it gets going. Let it sit for 15 minutes before trying to turn. This trick world better if the bolt was sticking out a bit so you could get vise grips on it, but with some patience it usually works for this situation too. Welding a nut on after wicking the wax is even better if there is room.

 

[buco]

curious, what time and brand of extractor did you use?

 

[JASTECH]

I would try a Cryobit first.

 

[lzenglish]

Hello, I tried to get in earlier, but the flood gates were open! Lol !!! In the future , pictures speak volumes, so, if you can, please provide them! My idea was this: Using a dremmel type small cuttoff wheel, and small drill bit, cut a slot in the stuck screw, and extractor. Be carefull to not hit the threaded walls, of the stuck screw if possible. Then, use a small chisel, to square off the slott. Then, grind down a flat tip bit, for a flat blade 3/8" Impact driver, turned to the counter clockwise position, and smack it hard. a couple of times! I have used this method before, and it did work for me in the past. If this does not work, I would try the nut over stud welded type of removal system, which I have never used, but have seen, and it looks pretty good, if you can control the rod. Best of Luck to You!

Wayne

 

[rsanter]

If its a really hard extractor i would try to shatter it first using a set of those cheap harbor freight transfer punches as the drift, your hole is just under 1/8 inch so i wouldn't mind sacrificing a few to try and shatter it first , if thats not possible then i would try to anneal with a torch as others mentioned... otherwise get the foredom out with some stones and carefully grind it away. We used to use an edm on some but you had to be able to build a clay dam around the area and fill with fluid for the submerged edm to work properly but that was many years ago, i'm certain that machine shops now have much more advanced edm capabilities now.

Try to break the extractor
You need a center punch that it very hard
Often you can use or take the tip from one of those automatic center punches

Bob

 

[jrlp]

Maybe post your location, maybe a member that's close by with the skills/ability can help you out. I'm in South Texas, and get at least 3 jobs a week removing broken bolts / taps / ez-outs...

 

[1967lemans]

Here is what has worked for me in the past. This happens about once a week where I work. If possible weld a nut as stated. Use a center punch to break chunks the extractor, broken drill bit, whatever is in there. We also use dental bits the drill a pilot hole. Haven't had to try it but I hear that a Alum dissolved in warm water will corrode and loosen ferrous metals.