Originally Posted by rebel heart
Once that's done and I drop it back in, what's the proper technique for under water preventive maintenance
I do not like to use metal implements on a bronze propeller
(my prop is bronze, at least), as steel
can scratch the soft bronze. I expect the propeller
shape is what the manufacturer wanted it to be, and I'd like to change that as little as possible.
For general cleaning
I just use a white or green 3M nylon scrubbing pad from the hardware
store. For scraping hard stuff off I use a 1" x 1" square hardwood stick (8" is enough to work with) as a scraper. The hardwood is strong enough to scrape off barnacles yet soft enough to not damage the bronze. The right angle edges of the stick eventually get chewed up and lose a sharp edge, at which point I run the stick through a tablesaw to true up the edges and get them sharp again.
As an aside, to clean the prop while hauled out, running sandpaper over a bronze prop can alter it's shape slightly; if you use a fine bronze wire wheel
chucked up in a drill you can clean the propeller without tearing up the metal.