RPM on blasted aluminum

question for you guys that have used rpm (rust prevention magic) on glass beaded aluminum. Does rpm darken the aluminum at all or keeps it as blasted? not looking for blasting tips just curious if it darkens the aluminum at all.

It does darken it slightly.

awesome. thanks

You may want to look into the ECS Ammo.

What about Alodine?

Light amber to a dark brownish tint depending how long exposed.

True statement if using Alodine 1201

If using Alodine 1001 it’s almost undetectable (will darken just a bit depending on strength of bath and exposure time).
This is what’s used on alternators and starter housings

i ordered RPM but have a couple gallons of alodine here for motorcycle stuff that i have done for customers. ill give it a try and see what happens. never thought of even trying it.

You never really mentioned what you are looking to protect, or why your concern with RPM changing the color. RPM is a fair (my opinion) corrosion protection product that can leave several finish differences depending on how you apply it.

So with a leap of faith I’ll assume your desire was to have corrosion protection on a piece of aluminum and want to keep the final finish close to natural, Alodine 1001 may be my recommendation, but not knowing the part or if you are wanting an OE finish it’s tough to say with certainty . Remember, the longer it’s in the bath the more the color will darken and take a very slight color change.

If your desire is to protect a piece of aluminum and would like to ensure 100% coverage, Alodine 1201 contains a dye that will visually show you treated surfaces by changing color to a yellow/gold/brown’ish color. This is very commonly used within the aviation industry due to its visual clues for inspector verification.

Best of luck with whatever you decide

Some Alodines do turn aluminum yellow orange, but some don't, like Alodine 1000, and are made to stay clear, like on polished fuselages. The old American Airlines, for instance.

Agree, 1001 is close to not changing color, but does to a small extent.

As for A/C exterior skins, those are Alclad (a very pure form of aluminum used for its corrosion protection) and no Alodine/Iridite is used.