Removing stump grinder bolts...help

You need a torch set, a dc stick welder, and a couple grinders. Anything else it's just a nice addition. The torch can do just about everything, just not as fast as other stuff. Get 6" grinders, so you can use 6" cut off wheels, which work way better than the little small 4" ones.

The reason I recommend stick welders is because they are more versatile and the smaller mig setups cannot compete. The only reason to use mig is for deposition rates (speed of welding) or for smaller stuff. However smaller stuff is easily welded with stick, and until you get to a full spray arc, mig is useless (except for small stuff). To hit spray arc heat, you need to be in the 250+ amps range, and you won't get that from a garage mig. Ironically, with proper rod selection, you would need to be using .045 dual shield wire at 300 amps plus to match what a 5/32" 7028 rod will lay down at 200 amps. Mig needs clean, scale free metal, stick doesn't care at all (still best to clean it tho). Stick will do cast iron, thicker al, all position steel (mig can too, but it's actually harder than stick out of position to do properly), arc gouge, and tig with a torch and argon bottle. You don't need a foot pedal and all that to tig weld steel and stainless.
 
SA200, a wet dream come true if there ever was one. A copper wound generator can’t be beat. Lincoln had a 300 Classic (I think) a few years back, diesel with a copper generator. I could listen to a sa200 run all day though, it put me in the mood, better have extra gas on hand.
 
:) when it idles up that burp sound, ugh....:spermy: staggered brushes (300 brushes in the 2 and 7 o'clock position) apparently calms it down even more, and makes it even sweeter.
 
That old boy got some spirit right there.
 
You need a torch set, a dc stick welder, and a couple grinders. Anything else it's just a nice addition. The torch can do just about everything, just not as fast as other stuff. Get 6" grinders, so you can use 6" cut off wheels, which work way better than the little small 4" ones.

The reason I recommend stick welders is because they are more versatile and the smaller mig setups cannot compete. The only reason to use mig is for deposition rates (speed of welding) or for smaller stuff. However smaller stuff is easily welded with stick, and until you get to a full spray arc, mig is useless (except for small stuff). To hit spray arc heat, you need to be in the 250+ amps range, and you won't get that from a garage mig. Ironically, with proper rod selection, you would need to be using .045 dual shield wire at 300 amps plus to match what a 5/32" 7028 rod will lay down at 200 amps. Mig needs clean, scale free metal, stick doesn't care at all (still best to clean it tho). Stick will do cast iron, thicker al, all position steel (mig can too, but it's actually harder than stick out of position to do properly), arc gouge, and tig with a torch and argon bottle. You don't need a foot pedal and all that to tig weld steel and stainless.

This..
Sean, keep an eye out on craigs list. I see Lincoln and Miller stick welders come up all the time for 200-250
Torch sets about the same or around 300.00.
Taint rocket science.
 
Seriously you guys working on equipment need to try the heat quench magic. Like the check plug in a rear end with the 1/2" square plug recess. I have had them rounding out from being stuck so tight and salt induced scale. Heat that sucker up to orange and spray with water. Some things might need a rinse and repeat, but magic will happen.
 
  • Thread Starter Thread Starter
  • #36
Thanks, Tom.
What am I at risk of damaging, if anything with heating and quenching?
 
It might take the temper out of steel. I have heated brake bleeder screws, sometimes more than once, and they come out without breaking. I used to dread those frozen little suckers. I replace them with new.

Never damaged anything doing it so far.
 
Since you are replacing the bolts, you will be fine. Water quenching can lead to cracking, but you are replacing it anyways.
 
How do you heat the bolt to red hot without heating the surrounding material? Is it because they are separate materials that the surrounding material won't get super hot if you are not directly heating it?
 
With an oxy acetylene torch, you just use a welding tip to concentrate the heat. You will still heat up the surrounding material from doing this, but by using parrifin wax it's easier on the steel because during hardening process oil is normally used. You can check the type of steel by a quick grinding test. Take a grinder to mild steel, and you will notice sparks. Now take a grinder to hardened steel, like an old leaf spring. You will notice a ton more sparks, and the sparks will be brighter. Then try it on cast iron, and you will notice the sparks will actually explode in the air. This shows the level of carbon in the steel. Also try taking a file to it. If you can't scratch it with a file, it's hardened. If it's softer than a file, you know that the file is harder, so it hasn't been hardened. Using these two indicators you can tell exactly what you are dealing with. If you can't get a file there, use a chisel, it will show the same thing
 
I have had the same problem.

I took an angle grinder to it and 10 minutes later they were off.

I think it’s being overthought.
 
  • Thread Starter Thread Starter
  • #42
Did you cut through the pocket to get to the bolt head, Mick?


These pockets are very worn, so new ones will have metal. I don't know how much imbalance will cause vibrations.
 
Yes, cut through the pocket to get to the bolt.

Don’t worry about imbalance, it’s not a chipper fly wheel, the wheels usually have dry mud on them during use, worn pockets are sloppy so can loose finger teeth easier, so you tend to over tighten......

Maybe replace all the pockets.
 
With an oxy acetylene torch, you just use a welding tip to concentrate the heat. You will still heat up the surrounding material from doing this, but by using parrifin wax it's easier on the steel because during hardening process oil is normally used.

That was a interesting post, but doh, I still don't fully understand how you avoid overly heating the surrounding material. Thanks.
 
A welding tip is very concentrated, enough to where you can get a bolt red hot, and then hold the wax on it. The other part will get warm, but not change color. With steel, color shows how hot it is. Furthermore, anything that's tapped will still be unhardened, because hardening could change the dimensions enough to where it won't meet tolerances. Works very well with cast iron and steel bolts, where overheating could crack the cast iron and ruin a much larger more expensive part. When I was rebuilding my welder, the head bolts were completely rusted in place. Cut the heads off the bolts in order to get the head off, which still took tons of effort (continental flat 4). Then I soaked the bolts in penetrating oil for a week, still nothing. Then I learned about the wax, welded nuts onto the bolts with a torch, then quenched the bottom with wax. Using a 3/8 rachet, they all broke easily and after a quarter turn, I backed them out by hand. Most amazing thing ever. It sounds like this wheel has pocket nuts tho, so on that case it's easier just to hack them apart.
 
So the wax melts and seeps in to make the thing able to be unscrewed because it is acting like Liquid Wrench or whatever penetrating oil and it lubes up the seized threads? Or is it something more magic and metallurgical than that?
 
I torch cut the far pocket that the allen screws into right on the corner then I sometimes unscrew it or just melt it, it all depends on my mood. Stress relief or my inner child playing.

Pretty much what Pete said.
 
Back
Top