Bronze corrosion
 

Frogwatch wrote:
On Sep 3, 10:02 am, Frogwatch wrote:
On Sep 3, 7:15 am, (Richard Casady) wrote:

On Wed, 2 Sep 2009 20:03:04 -0700 (PDT), Frogwatch
wrote:
Today, I dug out the old bronze prop whose blade edges were so
depleted of zinc
What kind of bronze contains zinc? Brasses are copper/zinc alloys,
bronzes are mostly copper/tin. Disappearing zinc is why brass is not
used in many applications.
Casady
OK. 'twas a late night brain freeze but the bronze is wasted and
corroded somehow.

Actually, marine bronze contains 9-10% aluminum which is even worse
than Zn. I do not have shore power so I can only assume someone else
has bad wiring. Right now, I am combatting this by having the diver
replace my zinc every 4 months but I will move my boat soon.
So, what do people think about my making the strut?
HK, you are incapable of giving useful input so please do not respond
I think you are probably capable of casting a strut but why bother? What
would a new one cost, $100 maybe. Chances are that there is an off the
shelf strut that fits your boat.
When you take the strut off you might find you need a bearing and shaft
too. And an engine coupler. And a new prop. And thru hulls. And
seacocks. And bottom scraping and painting. And blister repair. And
keel faring. And engine allignment. And bonding for thru hulls, strut,
and shaft.
Doing those kinds of repairs would be a waste of your time and talent.

Bronze corrosion
 

On Sep 3, 11:26*am, Jim wrote:
Frogwatch wrote:
On Sep 3, 10:02 am, Frogwatch wrote:
On Sep 3, 7:15 am, (Richard Casady) wrote:

On Wed, 2 Sep 2009 20:03:04 -0700 (PDT), Frogwatch
wrote:
Today, I dug out the old bronze prop whose blade edges were so
depleted of zinc
What kind of bronze contains zinc? Brasses are copper/zinc alloys,
bronzes are mostly copper/tin. Disappearing zinc is why brass is not
used in many applications.
Casady
OK. 'twas a late night brain freeze but the bronze is wasted and
corroded somehow.

Actually, marine bronze contains 9-10% aluminum which is even worse
than Zn. *I do not have shore power so I can only assume someone else
has bad wiring. *Right now, I am combatting this by having the diver
replace my zinc every 4 months but I will move my boat soon.
So, what do people think about my making the strut?
HK, you are incapable of giving useful input so please do not respond

I think you are probably capable of casting a strut but why bother? What
would a new one cost, $100 maybe. Chances are that there is an off the
shelf strut that fits your boat.
When you take the strut off you might find you need a bearing and shaft
too. And an engine coupler. And a new prop. And thru hulls. And
seacocks. And bottom scraping and painting. And blister repair. *And
keel faring. And engine allignment. And bonding for thru hulls, strut,
and shaft.
Doing those kinds of repairs would be a waste of your time and talent.

Jim:

You are right but I am obsessive. However, buying an off-the-shelf
strut might work even if the angle of the bearing is wrong. I can
make an adapter of G10 (glass/plastic material that is very tough) to
fit between the hull and strut to get the angle and length right so I
do not have to wait to have a strut custom made.
I've eliminated all below water thru hulls except the engine water
intake and I can replace that easily.
Blister repair: I've learned to ignore them.
Painting: No paint job I have had done by anybody else works as well
as what I do myself. When somebody else does it, it peels or does not
last very long. When I do it, I really prepare the surface, then 4
coats of hard epoxy anti-fouling, lasts 3-4 years.
Engine alignment: I installed the engine myself and I love it.
Alignment is truly easy with easy access to the engine on the S2.

Bronze corrosion
 

H the K wrote:
Frogwatch wrote:
On Sep 3, 10:02 am, Frogwatch wrote:
On Sep 3, 7:15 am, (Richard Casady) wrote:

On Wed, 2 Sep 2009 20:03:04 -0700 (PDT), Frogwatch
wrote:
Today, I dug out the old bronze prop whose blade edges were so
depleted of zinc
What kind of bronze contains zinc? Brasses are copper/zinc alloys,
bronzes are mostly copper/tin. Disappearing zinc is why brass is not
used in many applications.
Casady
OK. 'twas a late night brain freeze but the bronze is wasted and
corroded somehow.

Actually, marine bronze contains 9-10% aluminum which is even worse
than Zn. I do not have shore power so I can only assume someone else
has bad wiring. Right now, I am combatting this by having the diver
replace my zinc every 4 months but I will move my boat soon.
So, what do people think about my making the strut?
HK, you are incapable of giving useful input so please do not respond


Actually, I am quite capable of offering useful input on this and many
other boating subjects, and I think it a great idea for you to put as
many jury-rigged pieces and parts on your boat(s) as possible, so as to
increase the likelihood disaster will befall you while you are way out
of sight of land. That may lead to your family not having to spend its
assets institutionalizing you.

Your solution will certainly be cheaper than pulling your dilapidated
boat out of the water for a few days so that you can remove the corroded
parts and have someone competent fix up new or modified parts for you.

Whatever you do, when you rebed the strut, buy a can of sealant off of
eBay for the lowest possible price, so that when you open it up and find
it has turned into granite, you can then experiment with the chemicals
you have on hand to see what will turn it back into paste.


That wasn't "useful input" at all. We have seen what you call useful
input. Waahahaha. Entertainment yes, useful no.