"Norm of Bandersnatch" wrote: > Lew and All, > > Nipples (and pipe) are available in Red Brass, which is the same as > Gunmetal, which is Bronze. > > I have no idea why the cast fittings are called bronze, while the > pipe is > called red brass. Brass has a definite yellow cast while bronze has > a > wonderful warm reddish glow. > > The blades of my CP propeller, made by Hundested Motor and Propeller > Fabrik > in Denmark for North Sea fishing vessels, are made of gunmetal, AKA > red > brass. > > > Quoted from Wikipedia: > > Gunmetal is a type of bronze - an alloy of copper, tin, and zinc.[1] > Originally used chiefly for making guns, gunmetal was superseded by > steel. > It is called red brass in America.[2] Gunmetal is resistant to > corrosion > from steam and salt water, and is thus suitable for valves, pump > parts and > steam fittings. > > Gunmetals produced for different purposes vary slightly in > composition. In > some cases, the alloy may be composed only from copper and tin, or > from > copper, tin, and lead. It has many uses in industry, and is used for > statues and various small objects, e.g. buttons. U.S. Government > bronze > specification G is a gunmetal composed of 88% copper, 10% tin, and > 2% zinc. > U.S. Government bronze specification H is composed of 83% copper, > 14% tin, > 3% zinc, and 0.8% phosphorus.
It's been a long time away from my metalurgy training, but as I remember it's called Red Brass" not Bronze" for a reason. Bronze, by definition, has no ZINC. Zip!, Nada!, None! The copper alloy people suggest using copper/nickel alloys for seawater applications rather than copper/tin (not Bronze), but in either case, no ZINC. Norm, I have absolutely no doubt your prop supplier may have told you your prop was made of "gun metal"; however, since they are an offshore supplier, there is a possibility something got lost in the translation. I doubt there is any zinc, no matter how small, in your prop. As far as Wikipedia is concerned, just curious. Who or how is info vetted before it it published in Wikipedia? Will just have to wait for Lee's feedback. Lew _______________________________________________ Liveaboard mailing list [email protected] To adjust your membership settings over the web http://www.liveaboardnow.org/mailman/listinfo/liveaboard To subscribe send an email to [EMAIL PROTECTED] To unsubscribe send an email to [EMAIL PROTECTED] The archives are at http://www.liveaboardnow.org/pipermail/liveaboard/ To search the archives http://www.mail-archive.com/[email protected] The Mailman Users Guide can be found here http://www.gnu.org/software/mailman/mailman-member/index.html
