Poor Mans Guide to Extracting Broken Studs

Been doing a lot of work on the car as of late .

I've been putting a lot of my ideas on another car forum ..
Thought I would share them with you lot here as well.

This is my poor mans guide to extracting broken studs...IF YOU don't have oxyacetylene or engineers tools...I'm sure many people who read here have neather...so here goes.
I demonstrated these methods on the rover car forum ..to try to show all is not lost and with a basic welder you can win.


SHOWN ON THE BENCH ...BUT CAN BE DONE INSITU

This is what happened when I tried to remove my exhaust to manifold nuts.



And my cheap and cheerful methods.

Method 1

Well I started off with a stud extractor and a bar ...NO GOOD ..it feels like its going to slip off..





Method 2

then moved on to stud extractor and an air impact wrench ...NO GOOD...it still is trying to twist off the stud and shear it flush ...no movement at all !!!



Method 3
I knew 1 and 2 wouldn't work ..but felt I had to show other methods here ..
Any-hows on-to my favourite method.

1. Put an over-sized nut over remains stud, piece of steel is to protect lamda sensor.



2,Have your welder set at max .(mine was 180 amps) ..........and fill nut with weld and join to stud,

This has two effects :-

A ..It joins the nut on to stud almost permanently, so allows good grip with socket ........

B...It cooks the stud .....so expanding,contracting and heating it up many times hotter than it would have been, even heated by the exhaust...and breaks its hold, you may have to weld a nut on many times to each stud, as the nuts shear off several times, during this method.



All out ...the threads are undamaged ..the photo is showing ..just dirt....two hours work, it would be possible to do this on the car in-situ, That's if you like welding upside down



carries on...

These are all the over-sized nuts I used, together with the remains of the studs.



BTW ...when the nut and stud are hot squirt oil on them ...and the oil will become super heated and thin .....and will be drawn into the threads like plumbers solder.

If this had not of worked, then it would have been a drill out job..........but I was quite confident I wouldn't be drilling ....as I've done this many times .....even done it on Triumph stag head studs .that are notoriously hard to get out ..

All the best.........mark

There are a couple of specialty rods for stud/bolt/tap removal. Messer MG600 is the one I use. Harris-Welco Super Missle Weld is another. The advantage of these two rods over a conventional electrode is that they allow removing bolts that are broken below the surface.



The flux on MG600/SMW fills the thread space and prevents thread damage. Pretty easy to extract a bolt that's half an inch below flush.
--------------------
Barry Milton

I don't use a stick welder ...
been toying with the idea of next time using stainless mig wire ...maybe it's a lot harder than mild steel ..therefor I wont get so many shear offs.


all the best.mark

Mark,

I've tried to MIG them out, if broken flush or above the surface. As you know, the worst bolts to remove are those that secure an exhaust manifold With MIG, about half my attempts shear off before the bolt moves.

Both MG600 & SMW will produce 120ksi tensile strength. Standard MIG wire is 70ksi. That means the specialty rods are around 70% stronger. If a bolt is not badly frozen, MIG will get it out. But a MIG weld will break long before the specialty rod breaks.

My 3/4" impact is the tool of choice when removing larger bolts. It takes killer strength to handle over 1000 ft/lb (1355Nm) of torque.
------------------
Barry Milton

YES , thanks,
I will look into buying a small real of this high strength wire just for these jobs ...although it's no good quoting the ones you gave to me ...they probably wont of heard of them here in the UK.
I too use an impact gun on them ...but only half inch drive.

hmmm... maybe I need a 3/4 drive for the next time I pull studs out of a triumph engine ..when I will be using the high strength wire....me thinks though.

and will maybe have to learne stick welding

Barry, will you please elaborate on these rods? Are they stick weld? AC or DC? if DC, polarity? Amps? technique?

Thanks for the tips.

I'm looking forward to your next lesson: How to remove frozen and rounded off oxygen (lamda) sensors, without taking the whole #!*% manifold off. Any tips there?

awesome post,beats the alternative,drill,pray easy out! thanks.what automotive forum if i might ask? i hang out at one as well.

Are they stick weld? AC or DC? if DC, polarity? Amps? technique?

Click to expand...

DOM-

There are a number of makers of this type rod:

Certanium 707

Eutectic 680

Messer MG600

Inweld 955

UTP 65

Welco Super Missile Weld

Rockmont Brutus-A

They are stick electrodes & can run on AC or DC (reverse polarity, electrode positive). My TIG welder is used to run these on DC.

Amps vary with electrode size & bolt size:

3/32 @ 40-80 (for bolts under 3/8")

1/8 @ 65-120 (for bolts 3/8" to 1/2")

5/32 @ 90-150 (for the big 'uns )

The procedure is really simple. If below the surface, chase the threads to clear them of debris. With the rod centered in the hole, strike the arc on the broken stud & maintain a close arc (which is easy to do, these rods run like butter). Allow the deposit to build up to form a nub just below the surface. Chip the slag off the top of the nub.

Place a flat washer (slightly smaller ID than hole diameter) over the nub. Place a hex nut on the washer & continue the build up into the nut. Rap the nut with a hammer & wrench it off. A four foot cheater bar or big impact can help on the larger studs.

MG has a Tech Line that's helpful (800-558-8524) & they'll send info on request. UTP can be reached at 281-499-1212. Or PM with your FAX number & I'll send the three pages I have.

FWIW, the MG600 is sold in 2# packages for around $60. The Super Missile Weld comes in 10# cans for around $500. Rockmont charges around $100 per pound for theirs. Although they seem pricey, this is faster & easier than setting the part up on the mill, trying to indicate exact center of a rough hole or stud, center drilling, drilling to tap drill size, picking out the threads, etc.
------------------------
Barry Milton

awesome post,beats the alternative,drill,pray easy out! thanks.what automotive forum if i might ask? i hang out at one as well.

Click to expand...

Well I'm the only one that is sort of doing it the style of step by step at the forum ...much of the forum is about individual problems ..eg ..car wont start ..what's wrong ...would be of little interest to you.

However if you like my style of ...do it ...trip yourself-up..pick-yourself-up-again...go here to this thread.

Where there is me,trying to make a diary of sort ..with lots of pics ...
step-by-step presentation.
Including
Step-by-step core-plug replacement ..
Step-by-step Gearbox rebuild
and
COMING SOON
Poor mans engine rebuild
Sequential multi-point LPG conversion

http://forums.mg-rover.org/showthread.php?t=132776


all the best....mark

Nice work Mark

I have to agree with the point Barry made about achieving better penetration with stick welding, although I was unaware that anyone offered rods reccomended for this specific task, from Barry's list I only recognise Eutectic who if memory serves had a depot in Chester years ago. Quite often it is possible, with the right approach, to scrounge a slack handfull of rods from the manufacturers / agents to try out a specific rod, then you could brush up your stick welding technique & compare the two methods.

Although I have not done this type of job for ages, nor much stick welding, I think I used Vodex rods & perhaps Armorex for really stubborn studs.

Nice to hear that you are keeping busy with your usual diverse array of projects.

regards

Brian

I've had some luck in removing broken bolts and studs by starting with a LH twist drill. The force and motion of the LH drill bit work with you in getting the bolt/stud to start backing out.
Though I'm not sure this method would have worked on the condition shown in the images above.

Hmm, I think I'm missing something. If the *studs* are shearing, how would a weld with greater tensile strength be of any benefit? That would only matter if it were the weld itself that were shearing. What am I not understanding ... ??

they are shearing at the weld .

the stud ends up about 1mm shorter each time

all the best..mark

For studs broken off above the work,heat up stud/bolt red,put bees wax on broken piece,let cool,grab with vice grips,unscrew....comes right out.Works with oil gallery plugs in the front and back of blocks except you just have to get them hot/dowel pins to help get them out with a puller.If you can't find bees wax,go to the hardware store and get the wax ring that you seal your toilet to the floor with...bees wax!! Hey...I laughed too until I tried it..20+ years ago.

Booger

I'll second Booger's method! I've been using it for years and it works just like he says.

Corm

Absolutly! Bees Wax is the way to go. Bees Wax has a much higher fash point then any penatrating oils.
Bees Wax will penatrate rusted threads and will also kill Loctite.
Bees Wax candles can be found at craft stores.

Neat tips, Thanks! Me with a few herds of bees out back busily making bolt remover, & I never knew it was good for that. Will have to try some "next" time. smt

Put the torch to them before attempting to remove them and then 99% of the time they won't shear off in the first place.
If you are not in a hurry soak the rusted studs with oil of wintergreen for a few days.