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I am in the process of blacking out all the chrome and polished aluminum and wanted some wear protection on the flip gas cap, so I disassembled it and took it to a local anodizer. He was only charging a lot setup charge, so I threw in the wheel spinners as well for no extra cost. The outcome surprised all of us. The center threaded portion of the spinners that fit behind the wheel turned out perfect, but everything else came out a dark gray. All the parts were all run in the same bath at the same time. They believe the center threaded portion of the spinner was pure aluminum, whereas the gas cap parts and spinners were mixed with some impurities to save cost (they assume copper but the metal was not tested). They believe the impurities caused the anodized layer to be too thin, thus not allowing enough of the black dye to penetrate. They offered to run them through again, but were worried the acid may eat away at the impurities and pit the parts. So, I now have some parts with an excellent primer coat to be powder coated.
Just wanted to pass along for anyone in the future who is considering black anodizing the gas cap or spinner parts, be warned they may not come out black.
189556
Mike.Bray
08-30-2023, 10:37 AM
Knowing the alloy is critical for anodizing. I'm surprised your guy even tried not knowing what alloy the parts were.
Cast aluminum is the worst, it almost never works.
kirby
08-30-2023, 03:31 PM
Knowing the alloy is critical for anodizing. I'm surprised your guy even tried not knowing what allow the parts were.
Cast aluminum is the worst, it almost never works.
I completely agree. Even with the same alloy but different heats (or lots) from the mill will cause variation in colors. Welded parts can't even be considered to be anodized.
cc2Arider
08-31-2023, 10:37 AM
I learned this, too, just yesterday after my request for quote from the Anodizer came back with questions about the type of Aluminum the panels were made from...
Anybody know this?
Craig C
cv2065
08-31-2023, 10:48 AM
Why not just powder coat? Gas cap and spinners wear just fine.
edwardb
08-31-2023, 10:53 AM
I learned this, too, just yesterday after my request for quote from the Anodizer came back with questions about the type of Aluminum the panels were made from...
Anybody know this?
Craig C
6061
Jeff Kleiner
08-31-2023, 10:55 AM
I learned this, too, just yesterday after my request for quote from the Anodizer came back with questions about the type of Aluminum the panels were made from...
Anybody know this?
Craig C
It's 6061 which contains magnesium and silicon as its alloying elements.
Jeff
Mike.Bray
08-31-2023, 12:24 PM
I learned this, too, just yesterday after my request for quote from the Anodizer came back with questions about the type of Aluminum the panels were made from...
Anybody know this?
Craig C
As others have said the panels are made from 6061 which is a very good material for anodizing. I had my panels clear anodized and I'm very happy with them.
If you color anodize the finish will be matte. 6061 is a material that can be bright dipped which is a process that's done after the color anodize. Its basically a chemical polishing, turns the finish from matte to glossy. You get the look of paint or powdercoat but the durability of anodizing which of course is not a plating but a surface conversion. Worth checking out.
mikeinatlanta
08-31-2023, 01:46 PM
Haven't been around anything new in quite a while. Is FFR using clad 6061? Clad will anodize different than not.
For the OP: Suggest giving the name of your supplier. Him not asking or testing the alloy, and the reasons he gave you for the issue don't speak well of his knowledge. Pure aluminum is not alloyed to "save money". Any competent shop should know better. The odds of any of the parts being pure aluminum are very low. They are most likely just different alloys. Suggest staying far away from him in the future.