I'm not going to build Rainbow Brite, but some colours may be interesting. :P
The red and green turned out pretty good and the blue is always a favorite, but I'm trying to find a decent black or slate grey. I used a paste on Felicia (the catwoman sculpture if you remember that one) but it needs some maintenance. So a chemical that reacts with the steel and can be sealed would be perfect. Working on it. Watch this space. :P
This is an actual image of an artwork I did 15 years ago.
At that time I used a product prior to the one displayed in the link.
https://www.auro.de/de/produkte/holzfussboden/oele/126-hartoel/
I seales the surface perfectly.
The brand is still the same.
I didnt mind that it was develloped for wood.
You can always polish it up again with a soft brush.
U.
A friend of mine recommended Owatrol oil. Perfect for metal.
Sorry, I didnt want to bother you.
I just wanted to show,
that there are no signs of corrosion after all this time,
and the colours are really fired up by using this.
Please go on producing, you are a really great metal artists.
U.
Oh, but you're not bothering me. I just wanted to tell you there is something similar which is made especially for metal. Nothing else. :)