We apply a patch to a bolt, but the bolt had a cad plate and yellow dichromate ... now its turning black(carbon original color) and want to turn it back into the yellow dichromate ... can we do it without damage or heating the bolt ?
Margarito Romero fasteners - Hawthorne, California ^
I think you would need to either replate and rechromate the whole bolt, or brush plate and chromate the selected area. While the latter is doable, it's liable to be fairly costly in terms of labor. I don't know if this is "just a bolt" or a super-duper one of a kind.
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