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Rusted nut on stud problem

Nut on stud holds thick metal plate. Everything badly rusted together. Impossible to twist nut with wrench or socket without rounding or deforming it. Access from the side is a problem, so difficult to get hacksaw or dremmel directly against and parallel to the plate to saw the nut/stud off. I got to thinking I might could use a drill bit to drill several holes around the circumference where the nut/stud/plate meet to free the nut. Other ideas?

you might want to try to heat up the bolt with a propane torch.

An oxy-acetylene is better than a propane if you have access. Heat it cherry red and it will usually come right off. Mapp gas is hotter than propane as a second choice. Heating it as hot as you can get it and spraying with penetrating oil to shock it sometimes works. Turn the flame off tho, some of those penetrating formulas burn.

I may not understand completely your situation but never minded busting a bolt unscrewing the nut, and then replacing the bolt and a new nut and washer.

It’s sort of hard to create a suggestion without knowing what stud, what nut, and what plate are involved. There are angle drills that might be able to do the job. Or perhaps a six-point, deep impact socket with a breaker bar could simply break it off. A six point socket doesn’t round nuts off anywhere near as readily as a 12 point socket does. But if the stud is in a blind hole in a hard to access spot the problem becomes much more difficult.

  • Can you post a photo?
  • Can you reveal what the parts are that are involved?
  • Is the assembly one that might be able to be removed from the bigger assemblage such that the stud/nut/plate cane be more readily accessed? Sometimes it’s easier to remove a whole assembly to get the smaller parts apart than to try to do so in an installed state.
  • have you tried soaking it all in penetrating lubricant?
  • can you get a “nutsplitter” in there?

The more information we have is the better the likelihood that a solution will present itself.

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I’m not the most experienced guy, but every time I have encountered a nut rusted to something, I have always been able to get it off using penetrating oil, an impact gun, a six sided socket, and patience.

Impact gun: The most useful tool I every bought.

I agree.

For corroded or stuck fasteners of large enough dimensions, an impact gun or impact wrench, is very useful. The rattling action gives a big advantage over brute force.

Even with my cheap, cumbersome, not very high torque, HF corded electric impact, I have easily rattled loose fasteners (admittedly, sometimes it took a while or multiple goes at it) that I probably would have broken off by just leaning into a long handled breaker bar.

However, we don’t know if this fastener is beefy enough to withstand such a trial.

I can’t help but wonder why someone who has an answer for almost every question asked here needs help with a stuck bolt.

We ALL need help occasionally, Volvo. Those who think they don’t probably need it most of all. it is those who never think they need it that never learn from others.


When the wheel’s lug and stud are sunk in the well of a cast allow wheel torches, saws and chisels won’t work. Drilling the stud is often the only solution.

I had to use the oxy-acetylene “Hot Wrench” frequently when doing exhaust systems. It seemed to usually work first time, every time. Other methods? Not so much.

I was trying to salvage some steel that had been outside for about ten years and bolted together with a hex socket on one side. I finally gave up and cut them off with the angle grinder. If it’s a stud though, at least you don’t have to worry about trying to hang onto the other side.

Very good advice for wheels. I think that’s not what @GeorgeSanJose is dealing with here.
"Nut on stud holds thick metal plate."

Thanks for all the ideas. I’ll keep them on file for the next time.

So what did I do? I tried the propane torch heat method, no good. 6 point impact socket/breaker bar, no good. I could have probably soaked the works long enough in rust dissolver to work it loose eventually, but not enough patience for that. So I ended up cutting the stud off with a sawzall/hacksaw blade, there was about 3 mm space on the other side of the plate where I could get access. It took two blades to get all the way through. It wasn’t actually a stud, it was a 5/8" diameter 1/2 HP electrical motor shaft, threaded at the end. I preferred to not to cut the shaft, or at most only cut the threaded portion off, but alas the more robust cut, that’s all I had the patience for. At least the plate is off and I was able to save the brass bushing to revive the motor for another use.

I have used something like this set. It grabs the outside of a rounded nut. And, when it’s on sale HF will sell you a 25" breaker bar for about $10. So far it’s been good enough.

Too late now but I did see a method on youtube for getting a stuck pulley off of a lawn mower transmission. He heated up the base and melted wax on the shaft. Once the wax traveled all the way through, you could pop the pulley off. No idea if it would work on a nut.

I have that bolt extracter set and several other similar sets that are sometimes successful but none can be counted on. Heat, cold, candle wax, air impacts, nut splitters, special sockets, etc ad nauseum, are just part of the investment mechanics must make in order to get the job done. And guessing which tool to use and then using it properly are a big part of being a $uccessful mechanic.