Thoughts on how to Approch this Job?

[mageych]

My first steps into MIG welding, ir weldibg of any kind for that matter...

This is the front left mount of the tub on my Hilux a notorious focus of rust.
To remove the tub had to open a hole in the floor so that I coul drill the head off this bolt. It had cirrided so badly that what was 17mm across the flats varied between 13.5 and 15.
Anyhoos, the tub is off and I need to get that bolt out. My thoughts are to place a suitable (M14) nut over the remains of the M12 bolt, then use my SIP Migmate 130 to weld down through the centre of the nut to attach the two.

My very first attempt was not a success, mostky due to the state of the migmate. It was gufted6by a friend after laying around in his garage oir a few years. Thanks ro members on here repkying to my intro I have stripped and cleaned the wire feeder and guide and it works so much better...

So, to my question, at last! How would you approach this on a SIP Migmate 130? In fact is it even realistic to attempt it this way?
The bolt is a M12, the wire is 0.8mm and the SIP only has switches to regulate the power.
I am assuming that this needs the switches in High,Max and wire feed somewhere around the middle.

Would ut make sense to try to build the height of the bolt remains with some beads of weld then grind back to fit all the way through a nut first?

 

[Wozzaaah]

Max power. Weld an M12 washer over the stub, weld an M14 or even M16 nut onto the washer.
By the time you've done that the stub should be nice and hot so should come out fairly easily.
If it breaks off just repeat the process using new nuts and washers.

 

[Erie Fred]

My first steps into MIG welding, ir weldibg of any kind for that matter...

Your first step is to practice on some scraps until you get it down pat.
Planning on putting something to shield the plastic tank ?

 

[tom2207]

Your first step is to practice on some scraps until you get it down pat.
Planning on putting something to shield the plastic tank ?

a wet rag over the tank ,,,, and a metal heat shield between where your working and the tank , and have a fire extinguisher to hand ,,, providing its diesel it will be grand ,,, as for the job ,,, just cut the square bit off the top , leave the legs in place , weld a flange nut behind a new square of 3mm and tack the whole lot on ,, save a lot of messing about if your not great with a welder ,,, or just drill out whats there and tap it again ,,, lots of options wit and without welding ,,,

 

[mageych]

Your first step is to practice on some scraps until you get it down pat.
Planning on putting something to shield the plastic tank ?

Yes, I have an old fire blanket for that I have also moved it further away since taking the photo.
The proximity of the tank is one of the reasons that this job has been more complicated. Drilling through the tub to take the head off the bolt was the only safe option.

 

[Dozzer]

You could follow @Wozzaaah and do the welding method,
As you have got a good start with a dill, would be more tempted to use a good quality 3mm metal drill, followed by a 6m, and then one very close to the root of the thread, or use an easy out, but drive the bolt in, not out if there is more bolt sticking out of the other side under the bracket.

 

[mageych]

You could follow @Wozzaaah and do the welding method,
As you have got a good start with a dill, would be more tempted to use a good quality 3mm metal drill, followed by a 6m, and then one very close to the root of the thread, or use an easy out, but drive the bolt in, not out if there is more bolt sticking out of the other side under the bracket.

Sadly, the bolt is too long for that. It would need to advance 15mm or more to be free if the captive nut but there us less than 10mm between the end and the top of the chassis. I hate EZ outs, especially for a bolt corroded in place. A broken EZ out inside a corroded bolt is a whole new world of pain.

 

[indykid]

as for the job ,,, just cut the square bit off the top , leave the legs in place , weld a flange nut behind a new square of 3mm and tack the whole lot on

I'd be looking at this route, but maybe replace a couple of the legs too.

The leg has already corroded through behind the red circle and it's well on its way on the inboard side. It'd be a shame to lose the tub...

 

[Dozzer]

Sadly, the bolt is too long for that. It would need to advance 15mm or more to be free if the captive nut but there us less than 10mm between the end and the top of the chassis.

If there is that much heavily corroded thread to try and drag through the bracket, then as other have suggested, cutting off and making a new bracket my be less aggravation.

 

[the snooper]

Wozz has the best way, always worked for me, easy outs ? There are some good types and in my opinion very bad, I think the tapered types can expand the bolt if it's thin walled and I crease it's evil grip, the splined type are better but snap one and your in trouble

 

[tom2207]

Wozz has the best way, always worked for me, easy outs ? There are some good types and in my opinion very bad, I think the tapered types can expand the bolt if it's thin walled and I crease it's evil grip, the splined type are better but snap one and your in trouble

depends how your welding is ,,, remember the op is not proficient ,

 

[the snooper]

depends how your welding is ,,, remember the op is not proficient ,

True but, a little practice on thick steel first, don't have to worry about burning through

 

[dave h 2]

As per Wozz, just weld the nut to the washer on the outside of the nut. I've had little success welding the inside of a nut to a bolt. Get it all cherry red and it should undo.
Bear in mind that mount needs repairing anyway.

 

[frank horton]

remove the tank....too risky even for experienced welders.....besides, when the chassis is empty u can clean and repaint....