Oven Blueing Chain Mail

After degreasing the mail shirt, I let it air out for about 2 hours and started to preheat the oven. It seemed impossible to remove all the grime with mineral spirits, so I decided to risk a soapy water bath using my trusty 5 gallon bucket. Much to my relief, after 2 or 3 water-soap-swish cycles, the water started running clear. I rinsed the mail 4 or 5 times until there were no more bubbles in the rinse water, then transferred to a towel for a quick dry.

Moments later the mail was in the oven. I figured the mail would be difficult to heat evenly through-out, and therefore color unevenly if not careful, and I was right...

I set the oven to 375F (75F below my desired temp) and let the chain mail come up to temp for 30 minutes before progressing to 450F. I had planned on rotating and flipping the mail every 10 minutes, but we had unexpected guests and I let the mail sit in the oven at 450F for an hour. Big mistake! Most of the mail turned out perfectly with a nice golden-orange hue, but the links around the neck and some others on the back obviously hit somewhere near 525F due to uneven oven heating, and turned to a dark purple color. The rings are very small and those exposed to the exterior will heat up quickly.

In a panic I pulled the mail out and quenched in water. I was able to partially repair the darkened links by using a fine buffing dremmel attachment to knock the links back to their starting state. At this point the mail shirt looked like crap.

I put the mail back into the oven, this time at 450F, and watched them carefully. The blued links did not darken any more, and those I had buffed darkened, unevenly, though not as bad. Finally, I quenched the mail shirt in an oil/water bath of about 4 gallons total, dried on a towel for a few minutes then placed back in the oven at 200F to remove the water. I am happier with the result than I was with the plain mail shirt, so I'm going to call this a success.

In the future, I would heat the oven to 415F and turn the mail shirt shirt often, every 5 to 10 minutes, by taking the shirt out of the oven (using oven mitts), place into a large metal bucket, refold and then reposition in the oven. Go slow!

Be warned: ovens may not heat evenly. If you have a convection oven, good on you. If not, be very careful about areas near the top and sides reaching +50F the median temperature.

Note: I noticed a very small amount of corrosion on about 20 links. I should be able to clean this up quickly with a dremmel & jewelers cloth polishing mandrel. In light of this finding, I would advise quenching in 100% vegetable oil.