cold blue on moulds

[.22-10-45]

hello, I read where Cheese1566 thought about cold-bluing a set of mould blocks, for I suppose cosmetic reasons. I have also seen where some wanted to re-blue cavities after lapping or cleaning, the thought here is probably to restore the blue colored oxidation that was on the factory product. ...DON'T DO IT!!! after a sutiable break-in the cavities will turn a straw and later blue all on their own. the outside will probably remain a dark straw but depending on heat of alloy. I used cold-blue on the underside of a sprue plate on an old IDEAL .22536 I had trued up, as soon as mould came up to temp, it almost made me sick! never did burn off, I had to stop & polish off all blue before stink would stop. Your not supposed to get this stuff on bare skin...breathing fumes much more dangerous.

[cheese1566]

thanks,

I didn't do it yet, sure won't now!

I'll let it age naturally.

[HORNET]

That's funny, I've cold-blued several cavities and a whole bunch of sprue plates without any problems. Let it sit a while, wipe it off, and clean-up with bronze or brass brush. It may depend on whose cold blue formulation you're using.