OK folks, I've wanted to try this stuff out for a long time and finally decided to give it a go when I found some blued items that I could use as a test.
Here's the product Evapo-Rust.
As the package label says it's non toxic, it's not an acid, doesn't fume or foam has no odor and has the yellowish color of weak lemonade.
the product (Medium).jpg
My test subjects are a pair of Simmons sling swivels.(Say that three times fast.)
test itens (Medium).jpg
And the triggerguard and trigger from an old broken Czech.pellet rifle.
The swivels are nicely blued while the pellet rifle parts are more of a glossy black.
So I dropped them all in a shallow plastic dish and poured in enough Evaporust to cover and walked away.
in the tank (Medium).jpg
After 15 minutes I pulled the pieces out, wiped and photographed them.
at20 min (Small).jpg
After the first 15 min. the sling swivels are definitely showing more gray than black while the other parts have lost their glossy finish.
I repeated this after a total time of 30 minutes and 1 Hour.
After 30 min. the swivels are now almost the color of raw steel while the trigger guard and trigger are showing less black and more of a grey color.