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Painting Aluminum Wheels
I have visited your great web site and found the FAQ section to be very informative. You guys have done a great job.
I just bought a set of aluminum wheels that had been chrome plated on the rims only. Unfortunately, the chrome on all of the wheels is badly pitted and on one of them, the plating has come off in large sections. Under the chrome where the plating has peeled away there is a black substance that looks like adhesive, since it peels off the aluminum when brushed with a wire brush. In other spots where the plating has obviously been gone for a while, the surface is white, but rough and brushes off fairly easily. Is this where the aluminum was zincated prior to copper plating or is an adhesive used to put the copper on?
I would like to clean the wheels and paint them. I don't really want to have them replated. My questions are:
What is the stuff under the plating likely to be. Is there an available chemical that can be used to remove it, or can it be removed mechanically (sanding).
Is it likely that the chrome surface can be sanded to provide enough "tooth" for paint to stick to it?
Is there a way to etch the chrome plating that will allow paint to adhere to it well?
Do you know of a primer that can be used as a coating between the chrome and the paint?
Must I have the plating removed electrochemically?
I appreciate any thoughts you might have on this. Thank you in advance.Larry Robison
Yes, I think the black stuff you are seeing is the zincate layer which precedes copper plating.
Chrome is easily removed with hydrochloric acid (follow safety precautions with this hazardous material), and it must be removed since paint will not adhere to it. Under the chrome will be nickel plating, which is not easily stripped at all, but which should prove paintable after light sanding.
However, I think the paint on these wheels will be vulnerable to chipping since you won't be able to apply a chemical pretreatment that works on nickel, bare aluminum, oxidized aluminum, etc. I think you'll make serviceable wheels, but not show wheels.
Ted Mooney, P.E. RET
Pine Beach, New Jersey
I have a similar question to the original about painting aluminum wheels. I have factory painted aluminum wheels that are less than one year old. I want to change the color but insure the paint is serviceable. Is sanding the surface adequate? Or do I have to strip away all paint? What type of paint and clear coat if any is the best to repaint with? Do you see this as practical or not worth the effort?
Thank you,Doug McNames
- Hamilton, Ohio, USA
I refinished my wheels last winter and it was surprisingly easy and inexpensive. I went to Canadian Tire and picked up a can of paint that they sell specifically for wheels and a clear coat.
I sanded the wheels down with 180 grit and sprayed with light coats 2 or three times. they look great and have lasted the summer with many washes and many long trips with no chipping whatsoever.
All for about 20 bucks. You won't have a Canadian Tire store in Ohio obviously but an auto parts store should have the stuff somewhere. I've also heard of and seen wheels with just high temp paint and it worked well.
- Ottawa Canada
August 19, 2010
I just bought a new set of aluminum wheels for my truck. The finish is a flat black paint. My truck is light silver with dark gray bumpers and trim, so I want to paint the wheels. I've seen various alloy wheels that were painted silver, but what really catches my attention are wheels that are a dark gray...I think sometimes referred to as black chrome. My question is regarding the prep prior to painting. I know they will have to be thoroughly cleaned, but since these are new wheels, is there anything else I need to do to get them ready for paint? Will the factory black finish act as a primer or should I completely strip them to bare metal? Thanks for the help.Mike Mathews
- Thomson, Georgia, USA