Refinish a Mercury Blackmax Outboard Prop?
- Thread starter jviss
- Start date
It doesn't have sufficient corrosion to affect the mechanical integrity, it just has some surface, white, aluminum oxide where the black finish has failed.
The aluminum oxide will protect the underlying aluminum. Keeping paint on a prop is a losing battle. The props action through the water will wear away the paint. Looks good in a show room though.
That's a good point. I have one of these props that has the paint worn off the blades and in use it retains a nice, dull-gray patina.
Maybe I'll just clean up this one and use it as is.
aluminum should be anodized to prevent corrosion. Anodize makes a pretty good surface to paint, but if it was bare aluminum and only painted then it will corrode. A plating shop can maybe strip the paint and re-anodize it for you. Not an expensive process. Another option is to use conversion coat (tradename Alodine) that also provides corrosion protection but not as good as anodize. This can be done at home if you buy the Alodine. Amazon.com: Henkel - Alodine 1201 Light Metals Conversion Coating, Quart: Gateway
You are right about anodize. But consider the cost and time to find a shop to strip then another to anodize, you could just by a new one. I believe that jviss is referring to a small HP prop for his dink.
In his last post he is just going to clean it up and use it as is. That is what I would do as long as it is structurally sound.
Dave makes a good suggestion. I can't anodize it since there's a bonded rubber isolation bushing between the bore and the aluminum prop that would surely be destroyed in the process, and I think the bore is stainless. I am familiar with Alodine, I may still have some on hand from my airplane days.
A new one is about $100, and I've ordered one, but I like to have a spare on hand, as you can "spin" this, and there's no wa to repair it, no shear pin, just the bonded rubber.
A new one is about $100, and I've ordered one, but I like to have a spare on hand, as you can "spin" this, and there's no wa to repair it, no shear pin, just the bonded rubber.
The nice thing about anodize or alodine is it chemically modifies the surface of the metal. It is not a coating like paint or plating that can peel off. It is not something "bonded" to the surface. You are creating chemical compounds that are part of the object itself.