Re: [SabreSailboat] Re: No Room for Stuffing Box Service
What, you never made a foxhole radio as a kid or read about how to make one in a Rick Brant Science Mystery?
A very important component, in addition to the use of a blued razor blade as a diode, is a cat's whisker made from a safety pin pushed into a graphite pencil stub.
CBOn Mar 31, 2013 7:41 PM, "Jim Starkey" <jim@...> wrote:I'm having a lot of trouble with this. Maybe somebody can explain.
Bronze is an alloy of copper and tin, often with other stuff like nickel thrown in. Copper alloyed with zinc is brass, not bronze. As I understand it, there is no such thing as bronze with 30% zinc. (Historical note: bronze cannon were sometimes referred to as brass, or so Patrick O'Brian (sic) has Jack explaining to Steven.)
Graphite is carbon. It isn't a metal. It's soft and moderates neutrons (if sufficiently pure), but doesn't react with anything but oxygen and neutrons.
On 3/31/2013 7:11 PM, tim_woodworth88 wrote:
RC from Mainecrusing sent the following to me last year when I was in throws of the same project. He gave me permission to repost his comments.
R.C. writes -
As for GFO and bronze. Graphite is one of the most noble metals on the galvanic scale and zinc one of the least. Bronze shafting is between 32 & 40% zinc. Even a slight malfunction in your shaft zinc and the graphite goes to town pretty quickly on the shaft. Depsite the ABYC prohibiting the use of graphite impregnated packing it can work well on AQ-22 shafting providing good zinc contact and intact zincs. Zinc wear usually increases slightly with graphite impregnated packing.
It should be noted that ABYC P-6 specifically says this:
"6.7.4 Graphite impregnated packing material shall not be used because of the possibility of galvanic incompatibility with the shaft material."
This was a Sabre 34 shaft after one year with graphite packing on a bronze shaft. Shaft was like new prior...
--- In Sabresailboat@yahoogroups.com, "josrulz_2001" <josrulz_2001@...> wrote:
> Can anyone else confirm this issue?