Welding Tips and Tricks

I am making repairs to a damaged plastic injection mold. I will need to weld an area adjacent a chrome plated surface. The plated area is part forming and would need to be of an acceptable flatness and finish when complete. That being said, simply grinding the weld away will need to be done with kid gloves.
The hot zone is really small with this laser. I would think as long as I ground beyond the hot zone I should be safe?

I used to fix race car parts and pieces. None of those parts were chrome plated to allow for welding in case of a needed repair. I don't want the in depth metallurgical explanation but why exactly do we not want to weld chrome plated areas? I know chrome is damned hard, I would assume it would contaminate the weld to the point of sacrificing its integrity. Am I close? I don't remember ever needing a more in depth explanation so I guess that's why I never really asked before.

I have successfully made repairs (in a pinch) to chrome impregnated mold components. The base metal was 50s Rc H13 and I was advised to use 420ss filler. The parts were set for a more permanent repair but run frequency never justified the repair so things are as they were and working.

Thanks,
Fats

Everything has been worked out, and explained quite well from a different source.

I've always worked in a well ventilated area so the health concerns have always been considered while welding chrome or galvanized.

I learned early. I built a bunch of heavy duty engine stands while in high school. The first couple out of galvanized pipe. My metals teacher helped, he actually took a face full of fumes several times, he missed school for a few days thereafter. Then he realized the hazards and passed it on. He was machine shop more than welding teacher and I would guess those hazards had never been explained to him. That was in the 70s, I never did know of him after school and can't find him anywhere electronically, so who knows.