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Finishing Aluminum and Zinc

I am looking for some basic direction for finishing an aluminum casting. The 356T6 casting has a groove in which we lay a heater wire. We use solder made up of about 97% Zinc to cover and hold the heater wire in place. Does anyone have any suggestions about a possible method of finishing over the aluminum and zinc? I have thought about using a powder coating but I am not sure how the two different materials will be affected. Any advice?

Mike Etten
Rosemount Aerospace - Burnsville, Minnesota USA
2000

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dear mike

i have had a lot of experience coating aluminium. you can coat with powder.

first you need to clean the item with a solvent i.e., trike or sprit based solutions. then use a primer the sort used by car manufacturers two pack etch. then when primeris dry coat with powder and stove. check after stoving to make sure you have a coverage of approx. 60-70 microns. this should help but with ali it is all a lot of time,trial,tears and effort. just make sure all your pretreatments are carried out well before you coat.

yours
v mills.

vince mills
freelance - england
2000

I have experience engineering systems for powder coating OEM aluminum wheels. You didn't state the quantity. If it is low, I suggest going to a local Job Shop/Custom Coater for assistance. I looked in the Job Shop listings in finishing.com, and there is one in St. Paul. So near yet so far sometimes! I don't know them, but I'm sure they will be able to help you. If the quantity is lage to justify an in house system, then there are people to help you in the consultants listing.

Randal Rockwell, PE
Rockwell Engineering Solutions - Mishawaka, Indiana
2000