Last one I did was well and truly seized in - the impact gun rounded off the bolt head.
I got the arc welder out and welded a bigger nut on the end, then with a 3/4 drive socket and breaker bar it finally moved.
Turned the current way up when welding as this transfers heat directly into the bolt, causing it to expand a bit and loosen the rust.
When it had cooled down but the hub was still warm, sprayed the bolt with freezing penetrating oil, and with a fair bit of swinging on the breaker bar out it came.
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