Mystery wheels

[Glen Plumridge]

I think of it this way, if track links were pure cast iron, then they would be brittle in it's normal state either hot or cold.

"Malleable cast iron" means it has had heat treatment up over 900 C to change the grain structure.

In my opinion as a welder / metal worker, heating up to around 200 C would have minimal, if any affect on the grain structure. Especially if they are cooled gradually and not quenched.

If you were to get them glowing red hot and then dump them into a tub of water then yes, problem.

The temp of the fire was around the same as if you were cooking on a cast iron pan. That sort of temperature doesn't make the pure cast iron pans brittle so I don't think the effect on track links is as bad as might be thought.

Having said that, I do accept that there is potential for a problem to arise if the metallurgy is not what we expect and will try the chemical options for a bit of a longer period to loosen links in future.