Cold blue for rust protection

[ddmckee54]

After my brain-fart of knocking my Sherline off the bench a couple of weeks ago, and mostly repairing the aftermath of said boo-boo - I was left with several steel parts that now have scars on surfaces that were previously blackened.

I have seen several people that use a cold bluing solution for rust protection on jigs and tooling that they have made, so I decided to give it a try. Brownells was one of several solutions that I had seen used, so I ordered a small 4 ounce bottle of it.

Never having used this stuff before I wanted to see how well it worked, so I tried it on the top die that I made to press 2mm U-bolts. That die was milled out of a piece of 1/4"x3/4" hot rolled flat bar, so no harm-no foul if it turned out like crap. However I was impressed, it turned a nice deep black. And, considering that the only prep work it got was being wiped off with a paper towel the surface color is remarkably consistent. The next part that I cold blue will be properly cleaned before bluing. Any tooling that I make from now on will also get this cold bluing treatment.

Don