Adding Patina to Aluminum Parts

I found this out by accident today. Glass beaded this intake and was getting ready to paint it and the road draft hole was full of sludge. I soaked it in my parts cleaner (old deep fryer filled with Cascade dishwashing detergent and hot water) and when I pulled it out it had a purplish look and some light corrosion. Kind of looked to me like weathered magnesium. Figured somebody might want to know this if they were trying to give some aluminum wheels a weathered look.

 

Cool. I have also seen aluminum blasted with steel shot to give it a magnesium look.

 

tell me more about cascade and hot water please

 

Not to sound like a jerk or anything, but I prefer patina that's been earned over decades of use.

 

Im not sure how it affects aluinum, but im restoring a fm2 wildcat at work and we use sodium hydroxide and water (brought to a boil in a frydaddy) to strip CAD2 plating off of our hardware for the plane,(trying to keep it period correct for air shows, they didnt have CAD2 in 1944). i noticed that if you left the hardware sitting in the mix it would corrrode just enough to be oxidized after you wiped the corrosion off.. i can throw some aluinum in there tomorrow and get back to you on it.

 

Don't leave any aluminum in there too long - it won't be there when you get back!

 

I have an old electric deep fryer, fill it with water and enough dish soap to make the water cloudy. Then heat it to 200 degrees. The front of that intake sat in there for about 45min. I use sodium hydroxide in my jet washer for cast iron It will errode a piston pretty bad in about 15 min.

 

I wouldnt think it would dissolve the aluminum. I just noticed how it reacted to the steel, thought it might leave a nice weathered finish to aluminum too. but since you said that im definitly throwing a peice in there tomorrow just to watch it dissapear!

 

Fail

 

Sodium hydroxide is more commonly known as caustic soda, and yes it will dissolve aluminium. Completely.

It depends on how strong the solution is, how hot and how long you leave the aluminium in there. It will also dissolve your hands and your clothes so use rubber gloves, apron and safety glasses.

It's a common ingredient for detergents, especially for dishwashers because it will remove grease without scrubbing.

That said, there's no reason you can't use it for texturing the surface of aluminium, just make sure it's rinsed well after.

 

I sprayed a brand-new aluminum intake manifold with Easy-Off oven cleaner, twice, rinsing between coats. Was amazed at the outcome. FYI..

 

Patina sucks.

 

want patina throw it in the ocean

 

Then why did you even bother to open this thread? Waiting decades for patina isn't an option for some of us. You apparently have lots of time.

Bob

 

Dragging this back up for those that are running out of time for the patina to occur naturally.
I see that Stromberg now offers a " barn find" finish on their new 97`s.

 

W used to wrap motor cycle cases in an oily tote sack and bury them for a while. A week to a month depending on the weather. Unwrapped and cleaned they looked like they looked they were old and cleaned up.

Your method is faster.

 

pee on em

 

Ah! you want patina on alloys?
Have your cats piss on it.. Ask me how I know lol
Cat piss is some caustic sh*t I tell ya'!

 

That's for jelly fish stings!