[wp6529]

I have two cast iron hubs that I need to repair some serious worn areas on. The problem area is about 4" diameter and is worn up to about 3/8" deep about halfway around. These ride in nylon bushings and are a pivot point, not full rotation, and someone did not replace the worn out nylon bushings resulting in the metal-metal wear.

From what I think I know about this type of repair I think the part will need pre-heating (O/A) and then buildup with a nickel type stick electrode, followed by turning back to proper diameter in the lathe. Can those who have done this before give me some advice on pre-heat target temp, rod selection and anything else I need to know before attempting this?

Thanks,

Pete

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[wp6529]

When I have a chance later I will try the spark / file tests to try to confirm the material. TIG is also an option if it might be better.

[wp6529]

More searching and it's appearing that TIG brazing with ERCuAl-A2 may be the best bet and far cheaper than nickel rod.

[leadpig]

Nickel rods are ridiculously expensive, around £150 per kg (2.2lb) over here.
But they do work well, I fix a lot of cast gates and railings some of them need a inch thick of build up, I've never pre heated or wrapped after welding and not had any crack yet, in fact some of them actually say no need to preheat on the box. I just do small runs then tamp with slag hammer, over fill and grind back