Broken rusty bolt/stud removal

[forty40]

Broken off bolts always give me trouble. I have tried all kinds of drills, left hand, right hand, chiseling, punches, easy outs of all sorts, and the score is "Rusty Bolts" 100 to "my" 1.

Where a bolt has broken off flush, I try welding on a hex nut and after breaking it off and rewelding for the 6th or 7th time, eventually it may turn out. I need to give Bob at Triple G Services credit for this trick. He said, "Weld a flat washer to the broken off bolt instead of a nut".

The cast iron radiator parts on my JD A had 7 broken off bolts, so I gave the flat washer idea a try. Bent an ear on the flat washer to grab with a vise grip, tig welded it to the broken bolt, heated the area gently to around 900 deg with a rosebud and with squeeking and sqawking, it came right out.

Maybe everyone but me already knew about the flat washer idea, but in case there's someone else that didn't, it works. See the attached picture of flat washer-welded-to-broken stud...extracted.

 

[JRosenberger]

Neat trick.

Somebody spent some time on that cylinder head in the background. Head bolt spacing looks similar to a small block chevy but spark plug orientation does not. Care to share any details?

 

[JMS/.MN]

Candle wax???? I"ve used the nut welding countless times, never the washer, and then the nut. Always figured that was just redundant, but...whatever. But wax? Do the welding or torch heating....and as it cools, apply candle wax. It seeps between the threads to loosen them. Sometimes works right away, sometimes leave it sit til the next day. No rush...will still turn out easily. Never fails for me, even if it takes a couple of times. Last year I had a stuck spark plug in my Ford 3 cyl backhoe. Couldn"t heat with torch, but got the engine running, and applied candle wax to the recessed plug two times........engine heat was enough to melt the candle, got it turned out without stripping plug threads or breaking anything.

 

[John T]

Yearssssssss ago I heard of and on my own figured out if you FIRST welded a flat washer to the remnants of an exposed stud it was MUCH better then trying to weld a nut BECAUSE THE BIG FLAT WASHER prevented weld from getting on the head or block etc and allowed a nice circular surface area on which to weld.

HOWEVER then instead of trying to turn a raised portion of the washer I would weld a nut to the washer again with the washer protecting the head/block plus a good surface onto which to weld the nut

THEN after allowing things to cool place a wrench on the nut and out on the end of the wrench use a hammer to tap tap tap tap and shock the stud out versus a heavy dead pull which could break the welds.

Ive seen and tried candle wax which never worked for me and its hard to drill right in the dead center of the stud and easy outs I HATE LOL so my experience has taught me to FIRST WELD A WASHER AND THEN WELD A NUT TO THE WASHER AND THEN TAP TAP TURN TURN SHOCK SHOCK THE NUT ....

Seems to me the heat and expansion followed by contraction seperates the stud from the rust and corrosion and female threads so the stud can turn out...

Works for me and fun to hear other gents methods for this common problem...never too old to learn a new trick maybe

John T

 

[Hoenes]

I have a broken off bolt in an AC narrow front end. (1/2 x 1 1/2) so it,s deep! Tried flat washer, nut, two times, twisted off both times. Tried to blow it out with a torch, with some success (got about a 1/2 deep) but the torch keep poping out/burning inside. Gave up on that for safety sake. Trouble is, now it,s hard as a diamond. Nothing will touch it, no center punch, no expensive drill bits. Now what?

 

[forty40]

In a video online (so take this with a grain of salt) a hardened area was heated up with a rosebud torch to a dull orange, a little over 1,000 F. Then while the area was still orange hot, using a standard hi-speed drill bit, it was drilled out to the next oversize.

Another possibility - If the bolt can be heated up again to a reddish orange, then using a pick punch or small chisel chip away the surface slag created from burning. Burning slag and about .015 base metal depth will be very hard, probably Rc35-45. If the slag can be chipped off, then heat the bolt again, allowing to cool very slowly which tempers (softens) the base metal. When cool, using a freshly sharpened drill, you might have some success. However, if the initial burning operation was extraordinarily brutal and mixed cast iron with steel, this is going to be a very difficult process, maybe not successful.

In the weld shop we have a tap disintegrator for these instances where a tap, drill, or hardened bolt has broken off below flush. I empathize your situation, it makes a person wish they could take a mulligan, do this over again...but some other way.

 

[Hoenes]

forty40,
Thanks for the "re-heating" tip to drill out while still red. Never heard of this before. I will try that next. You are correct about the cast mixing with the bolt steel. We used a 1/2 flat washer, which was probably too big, (and allowed the two metals to mix.) I wandered about that, but wanted to get as big a weld as possible. One more option, our neighbor has some government issue drill bits that came from Boeing's machine shop. We once used one to drill out a broken off tap in a u-joint collar. Must be made of something special.

 

[missouri massey man]

This is going to sound silly, but there is an extremely expensive rod made specifically for this application. An old buddy is a heavy equipment mechanic and uses them.....we need to ask one of the welders here if they can provide specific info. Anyway, this rod will not damage the threads in the block (or whatever) and is used to build up the material of the broken bolt (if its a recessed break) to the top of the surface and then a washer or nut or whatever can then be attached to the weld.

I have not seen it done, nor do I have any specific info on the rod, except what my old buddy has sworn he's done countless times with it. On heavy equipment though, you gotta be thinking of much larger bolts than these small farm tractors. I've seen him using 1" impact tools with super huge sockets and to support the impact he'd swing his auto-crane over and drop a nylon choker to hold it in line with the bolts.

A good trick is if you can find a portion of sheet copper, lay it over the machined surface with a hole over the broken stud to weld through. The copper will not allow slag or molten metal to attach to or damage that surface. Hang it on the nail and make a new hole the next time if necessary. Try it....you'll like it !!

It also works quite well to mig-weld sheet metal cracks, splits or holes closed in fenders, grills etc. You have to get creative sometimes in clamping the sheet copper securely on the back side of the material.

 

[alvan]

I think you are talking about a extracting rod it has a heavy flux rod witch wont let it stick to the metal around it. I used one to remove broken bolts out of a John Deere radiator worked great.

 

[40Utility]

(quoted from post at 10:13:26 04/26/13) This is going to sound silly, but there is an extremely expensive rod made specifically for this application. An old buddy is a heavy equipment mechanic and uses them.....we need to ask one of the welders here if they can provide specific info. Anyway, this rod will not damage the threads in the block (or whatever) and is used to build up the material of the broken bolt (if its a recessed break) to the top of the surface and then a washer or nut or whatever can then be attached to the weld.

I have not seen it done, nor do I have any specific info on the rod, except what my old buddy has sworn he's done countless times with it. On heavy equipment though, you gotta be thinking of much larger bolts than these small farm tractors. I've seen him using 1" impact tools with super huge sockets and to support the impact he'd swing his auto-crane over and drop a nylon choker to hold it in line with the bolts.

A good trick is if you can find a portion of sheet copper, lay it over the machined surface with a hole over the broken stud to weld through. The copper will not allow slag or molten metal to attach to or damage that surface. Hang it on the nail and make a new hole the next time if necessary. Try it....you'll like it !!

It also works quite well to mig-weld sheet metal cracks, splits or holes closed in fenders, grills etc. You have to get creative sometimes in clamping the sheet copper securely on the back side of the material.

Those rods are made by a company named Rockmount, I have used them with some success. I usually start by heating then, using a hammer and tapping around the broken bolt, then welding on the washer and nut. I only use the Rockmount rods as a last resort kinda thing. If its a small part I will machine it out before even trying them.