Suitable Welder for broken stud extraction

[fxmaster]

Looking for a suitable Mig welder to weld nuts onto some broken cylinder head bolts on my car (bolt heads have rounded).
One solution I've been told is to weld a nut onto the rounded head.
I've never done welding before but reckon with some practice first I could do this.
The bolt studs are approx 12mm in diameter.
How many amps would a suitable mig welder need to be to put sufficient heat in do this. Bear in mind these studs are tight/maybe seized; only rounded because of this I guess and broke a good socket in my attempts to remove.

Thanks in advance

 

[Jim_gsxr1000]

Its a bit of a very limited reason for needing a mig, if its 12 mm, ur going to need a machine that will do at least 6, around 200A comfortable, personlay if you dont have any other use for a welder id get a locaql mobile welder or a garage to remove the bolts.

 

[Badger1bear]

And buy some good sockets lol not ones made out of a kipper box in yakasacky land

 

[Woody.v8]

Cover all the oil ways and drill the heads off the bolts and remove the stud afterwards.

 

[fxmaster]

And buy some good sockets lol not ones made out of a kipper box in yakasacky land

It was a Sealy socket that broke. Then I got a Teng socket which didn't break but sheared of the top of one stud and rounded the splines on another in the effort to remove!!

 

[fxmaster]

Cover all the oil ways and drill the heads off the bolts and remove the stud afterwards.

This was my second choice - was trying to avoid having little bits of metal deposited around the head if possible. As you said if everything is covered up all will be ok.
I was was thinking the welded nut method would introduce some heat into the stud and help release it. These head bolts are either over torqued or partially seized to start shearing off!

 

[ibrooks]

I'd second the proper socket idea. If it's rounded a nut off then it wasn't a good fit to start with - metric socket on an imperial nut maybe?

Decent impact sockets are available in sets without breaking the bank and only have a single hex so get a much better grip.

Once a nut/bolt head is rounded it gets harder but Irwin bolt grip sockets will usually still get a grip and remove it. Getting the nut out of the socket afterwards can be a bit of a challenge though.

Iain

 

[super noob]

Will a proper stud extractor not fit ? Easier and safer if it will

 

[fxmaster]

I'd second the proper socket idea. If it's rounded a nut off then it wasn't a good fit to start with - metric socket on an imperial nut maybe?

Decent impact sockets are available in sets without breaking the bank and only have a single hex so get a much better grip.

Once a nut/bolt head is rounded it gets harder but Irwin bolt grip sockets will usually still get a grip and remove it. Getting the nut out of the socket afterwards can be a bit of a challenge though.

Iain

The bolts are E12 Male Torx so the sockets were E12 Female Torx and both the Sealy and Teng seemed to fit snugly.

Have you used the Irwin Grip Nuts yourself and if so in what situation? (I had a 24" breaker bar on these and they did not want to budge - that's a lot of torque).

 

[Badger1bear]

When you had pressure applied to the breaker bar it would of been a good idea to give it a sharp hit with a hammer, sometimes that's all that's needed for stubborn bolts hence the use of impact guns. As with everything in life, you have learned from this and hopefully won't do it again

 

[DrNik]

heating up the head of the bolt when welding a large nut onto the stud wont help, as it will soften up the bolts, id be inclined to either drill the heads of the bolts off remove the head and then you have plenty of stud to play with, when you weld a nut on a stud it does a couple of things, it gives you a hex nut to turn, and it also heats up the stud and expands in the engine normally causing the rust/crap to break the bond between the metals

 

[jordan1]

I find that this tool or similar is great for such jobs if there is enough to get hold of.:-


http://www.amazon.co.uk/Draper-1415...qid=1365615453&sr=8-1&keywords=stud+extractor

 

[ford34/2]

removal

The last similar problem I had in removing a Bolt that had been cut off almost flush, removal by normal turning didnt work due to threadlock and rust on the inside. It was threaded into a Tube with inserts welded in, the bolts went through the welded inserts and had rusted, However undeterred, drilled a descent hole in,not right through, filled the tube with oil, tiny wee hole drilled in.heated the lot up, squirted freeze spray in the drilled bolt stud, and inserted a screw extractor ( them horrible left handed things) tichy weeny bit at a time and it eventually came out took probably 1/2 hr +, More worried about the screw extractor snapping--as they do. Bolt was 1/2" Diam.
worked on the principlal of heat on the tube and freeze on the stud would leave a bit clearance, the oil would lube the inside threads -- was bloody hot!!!
unconventional but worked, alternative would be drill the lot out carefully on the lathe and clean up the threads with a tap.
Given the problem and how it was created in the first place you may be going to have problems with any type of stud extractor, a breaker bar is not something bolts like on the end of them.Bolts will laugh at any stud extractor.
Stan

 

[super noob]

Could put a nut over then plug weld that onto the top of the left over stud ?

 

[the snooper]

did you use 6 sided sockets ? they never round off a bolt

 

[fxmaster]

did you use 6 sided sockets ? they never round off a bolt

They are Torx type bolts (6 splines, socket size E12)

 

[normspanners]

This wouldnt be a Merc would it ?
When Badger says hit it with hammer he means not in the direction to undo, but down onto the head of the bolt through the socket.

 

[Badger1bear]

This wouldnt be a Merc would it ?
When Badger says hit it with hammer he means not in the direction to undo, but down onto the head of the bolt through the socket.

Thankyou bud thats exactly what I meant, sometimes you just need that initial shock with some force in place

 

[ibrooks]

I have used the Irwin bolt grips - they are the tool of last resort and have never failed to either undo a bolt or snap it off for me.

The sharp rap on the head of the bolt is a good one to try whilst there is a bit of tension on it. Sometimes a series of raps will do it with the bolt turning a fraction each time almost like an impact wrench.

It can also help to swing on the breaker bar a bit in either direction as it will allow the shaft of the bolt to twist and maybe free up inside the head. A lot of this comes down to feel.

You can often find that once the head is gone from this type of thing and the tension released the remaining bolt is little more than finger tight.

Iain

 

[normspanners]

What I have done in the past is to use oxy acet and heat the head of the bolt directly to red then beat it with a thick pin punch and lump hammer to thicken the head then you can reshape it by tapping the socket back on, by heating the bolt head, the bolt soaks the heat down its length and expands slackening its clamping force I did this only yesterday on some crown wheel bolts, the only issue here for you is if the head is ally it maybe tight due to electrolytic action between the bolt and the ally if no copper slip was used when built, then heating the bolt forces the electrolytic corrosion back and when the bolt cools it is a smaller dia and not locked by the corrosion.
You must used oxy assisted heat to put the heat directly into the bolt and quickly as using a 'blow lamp' would heat the cyl head and be counter productive.