Hole in casting... Fill or not?

pittsburghracer said

Are you any good with a mig welder or have any nickel stick welding rod. I always keep some handy.

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So I see now that JB weld is a nono, Belzona is a yes yes (if I can find it) and also wondering if I should just do a few practice brazes and then try on the block... I don't weld unfortunately. I only used to ever used braze bicycle frames.