Best way to remove this bolt (pic)

[chamy]

Whilst trying to undo a very old bolt, the head literally snapped off (although it did undo about half way before snapping).

Ive soaked it in penetrating oil for the past few days, and am now considering the best option for removal (other than drilling it).

Ive got a decent snapon bolt extractor, but also considered dremelling a slit for a flathead screwdriver, but cant decide which will have more 'torque'?

Or any other options ive missed out...

 

[tttonyyy]

Tack a smaller bolt onto it? The heat may well do as much to persuade it out as anything else.

 

[pedrobedro]

Put a nut on it and weld the hole up in the middle to the broken bolt. The heat will help release it

 

[chamy]

Forgot to mention, welding something onto it isnt an option (no welder where its based).

 

[octo0072000]

can you get to the other side of it
i.e hole saw then repair later

 

[rich r]

If the head sheared off, cutting a slot for a screwdriver is unlikely to work, as the screwdriver will tend to come out, or even shear off the remaining bits of bolt.

If you can't weld to it, then screw extractors or drilling it out are about your only options. Personally I'd drill it and retap the hole, as that usually works for me.

 

[stuvy]

If the head sheared off, cutting a slot for a screwdriver is unlikely to work, as the screwdriver will tend to come out, or even shear off the remaining bits of bolt.

If you can't weld to it, then screw extractors or drilling it out are about your only options. Personally I'd drill it and retap the hole, as that usually works for me.

same here if theres no access to a welder its the easiest way

 

[rtbcomp]

If it undid part way then maybe a slot would do - tighten it up a few turns, then screw it out a few, keep repeating with plenty of penetrating oil and it might eventually come out.

 

[Hitch]

If you have a stud extractor, and can get on it, just use that.

When you say stud extractor, I'm thinking the kind that fits over.....

 

[chamy]

If you have a stud extractor, and can get on it, just use that.

When you say stud extractor, I'm thinking the kind that fits over.....

Not over - requires drilling first.

Looks like one in the bottom left corner of this set:

https://webfiles.uci.edu/redwards/public/Snap%20on%20screw%20extractors%201-27-08.jpg

 

[the snooper]

this type of extractor

 

[rtbcomp]

This is type I have

http://www.drillspot.com/products/373477/Blackhawk_Tools_49980_Socket_1_2DR_Stud_Extractor

It can be used left or right handed, so can slacken & tighten a stud.

 

[MrFluffy]

Drill it and re-tap to size, dont bother with a extractor. If you pick the drill size correct you can sometimes pick the remaining thread out as a sort of springy wire and not even have to retap. I also drill with left handed drill bits so if it snags it undo's.

They are hard and brittle, and if the fastener has broken with the torque required to undo it, a smaller sectioned brittle extractor stands a good chance of breaking too, blocking the hole with shards of hardened extractor remains.

Is that on a fuel tank, is that why you cant weld on it etc?

 

[zzr1200]

The bolts thread above the fixed nut will be totally rusted which has caused the bolt to jam and snap off, the chances of you removing it are very slim.

You could try drilling it and hope it screws inwards and then leave the remains inside the chassis, if that fails drill and re-tap the fixed nut. Not many other options really.

 

[hareng]

Was gonna say exactly same as Fluffy, it works time and time again on irreplaceable items! Bigger the bolt the easier.


Choose an undersize drill and drill through centre. Just keep opening up with fractionally larger drills. ie assuming its M8 start with 4.2mm, 6.8mm is drill size hole if perfectly central.
If off centre whats left of the stud would just be the thread and can easilly be screwed out.

Bolts aint that hard to drill even done blind holes with right angle drill.
Worst case run a tap through after.

 

[BrokenBiker]

I'd go with the drilling and tapping myself, had to do it on my exhaust, on my bike resto, tried the stud extractors and puting vise grips on and stuff, but in the end i still had to drill and tap the holes again

 

[mpats]

I'll be honest, 9 times out of 10 I would use a screw extractor and try to avoid drilling and re-tapping. But that said I don't normally have to deal with the sort or probably amount of corrosion that you are dealing with.

Mind you it's normally screws with rounded heads and only the occasional sheared bolt. But working away slowly and carefully with a screw extractor and removing the duff screw/bolt is prefferable to making a mistake when drilling and having to replace an insert in a composite pannel or stripping a load of stuff out of an aircraft to replace an anchor nut.

Like I said, it's just my preference, each to their own.

All the best

Mal

 

[Angusdog]

Those stud extractors need more exposed bolt to grip.

I've had success with welding a nut on (for future reference...) and cutting a slot & using a screwdriver, but do you have access to the back? How about cutting a slot and screwing it all the way in to remove it?

 

[Spot the welders dog]

Perhaps a 'Speed Wrench' would be worth a try. Got me out of trouble quite a few times.
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