[dataway]

You are correct. I don't think from the factory phosphate was ever painted, it was meant to be oiled and retain oil.

I didn't mean to imply that only reason phosphate coatings were used was to promote paint adhesion. Most of the "metal prep" solutions you see for use on bare metal prior to painting, are phosphate.

Nuts, bolts, brackets get a hot phosphate coating which is porous and intended to do just what you have said ... retain oil to prevent corrosion. But I would imagine if you wanted to clear coat them it would stick very nicely.

[webfoot]

Gotcha! Probably a clear with a little flattening agent would look like oiled phosphate. Sounds better than crawling under a car to oil exhaust brackets.

[dataway]

I do some of my own phosphating in my shop and it does look great ... but yeah, miss the oil 2-3 years and it's going to start to rust ... I'm a believer in the satin finish clear, looks like freshly oiled phosphate for close to ten years. Similar to modern phosphate finishes on firearms of various types ... have to keep it lightly oiled to preserve the finish. Can't really clearcoat a pistol though