On Thu, 23 Sep 2010 21:53:36 -0500, David R. Birch wrote:

Durable cheap finish for home built receiver

I recently finished a home made AR-15 receiver made from 304 SS and
6061-T6 AL. Now I want to give it a cheap flat black or dark gray finish,
preferably something I can spray on and maybe bake in the oven. I remember
a discussion something like this a while ago, but I can't locate it.

Any ideas or suggestions, either for the process or locating the
discussion?

If you already have a battery charger, or know somebody who can lend you
one for a day, you can anodize aluminum at home for practically nothing:
http://www.thirdgen.org/anodizealuminum

As for the stainless, I have no idea what this stuff costs, or what alloys
it works with, but hey, it's a start:
http://www.caswellplating.com/kits/black.htm
(I googled "black oxide".)

Cheers!
Rich