Bronze corrosion
 

About three years ago, I moved my sailboat to a slip in a real marina
for the first time ever. I was surprised to see my shaft zinc go away
really fast. Then I noticed the edges of the bronze prop were really
rough and brittle. Uh-oh, So, I needed to get her bottom painted
anyway so had her hauled, not an easy thing to do around here (no
facilities). The bronze prop was a goner so I replaced it with a
PerfectPitch plastic prop that I like. However, the bronze shaft
strut also looked corroded but was good enough to last awhile. Now, I
have a diver check the zinc every 6 weeks.
So, I plan to haul her again soon and am thinking of replacing the
shaft strut.
Today, I dug out the old bronze prop whose blade edges were so
depleted of zinc that I could break off chunks of metal and examined
it. It was only near the blade edges that it was wasted of zinc
except a thin veneer of corrosion all over. The rest of it showed
good bronze when I used the dremel tool on it.
3 yrs ago when she was hauled, a small piece actually broke off near
the cutless bearing holder lip (not structural) causing me to think it
was wasted badly. This experiment makes me not so sure that it is
bad. I can only determine this by using the dremel all over the strut
when she is hauled. Anybody have any experience with this?
Now, I can have a strut made but that will prob take forever, they
have to use the old one as a model and cast it. I will not be sailing
again till next year, no good.

Hmmmm.......I've got a well equipped machine shop, so, maybe I can
make a strut. Maybe I can make a strut base from silicon bronze, make
a strut body from another piece bolted and brazed to base with a
cutless bearing holder brazed to that. Thoughts?

Bronze corrosion
 

Frogwatch wrote:
About three years ago, I moved my sailboat to a slip in a real marina
for the first time ever. I was surprised to see my shaft zinc go away
really fast. Then I noticed the edges of the bronze prop were really
rough and brittle. Uh-oh, So, I needed to get her bottom painted
anyway so had her hauled, not an easy thing to do around here (no
facilities). The bronze prop was a goner so I replaced it with a
PerfectPitch plastic prop that I like. However, the bronze shaft
strut also looked corroded but was good enough to last awhile. Now, I
have a diver check the zinc every 6 weeks.
So, I plan to haul her again soon and am thinking of replacing the
shaft strut.
Today, I dug out the old bronze prop whose blade edges were so
depleted of zinc that I could break off chunks of metal and examined
it. It was only near the blade edges that it was wasted of zinc
except a thin veneer of corrosion all over. The rest of it showed
good bronze when I used the dremel tool on it.
3 yrs ago when she was hauled, a small piece actually broke off near
the cutless bearing holder lip (not structural) causing me to think it
was wasted badly. This experiment makes me not so sure that it is
bad. I can only determine this by using the dremel all over the strut
when she is hauled. Anybody have any experience with this?
Now, I can have a strut made but that will prob take forever, they
have to use the old one as a model and cast it. I will not be sailing
again till next year, no good.

Hmmmm.......I've got a well equipped machine shop, so, maybe I can
make a strut. Maybe I can make a strut base from silicon bronze, make
a strut body from another piece bolted and brazed to base with a
cutless bearing holder brazed to that. Thoughts?


snerk

(For several reasons) :)

Bronze corrosion
 

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.

Bronze corrosion
 

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

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


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.

Bronze corrosion
 

On Sep 3, 10:24*am, 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 would not do the brazing or welding, I'd pay to have it done. I
admit, there are some things it simply takes too long to learn.

Bronze corrosion
 

On Sep 3, 10:39*am, 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.

See Harry, not only do you not provide anything useful, you don't even
read my post. I will haul her out and remove the old strut.
Please do not reply to this thread unless you actually have something
useful to add.

Bronze corrosion
 

On Sep 3, 10:53*am, Frogwatch wrote:
On Sep 3, 10:39*am, 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.

See Harry, not only do you not provide anything useful, you don't even
read my post. *I will haul her out and remove the old strut.
Please do not reply to this thread unless you actually have something
useful to add.

Hmmm, ok, here's a weird thought, I can coat the strut with gold.
Seriously, I can put it in the sputtering system and coat it with a
few dollars of gold or platinum, both very high on the galvanic
series.
Even better would be graphite. I have some conducting graphite paint
that might work.
Dont gold coins immersed for centuries in seawater always come out
shiny?

Bronze corrosion
 

Frogwatch wrote:
On Sep 3, 10:39 am, 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.

See Harry, not only do you not provide anything useful, you don't even
read my post. I will haul her out and remove the old strut.
Please do not reply to this thread unless you actually have something
useful to add.


I'm offering you "do-it-yourself" encouragement. What happens to your
boat or you because of your incompetencies is not my concern. Take
flajim and dk out with you...

Bronze corrosion
 

Frogwatch wrote:
On Sep 3, 10:53 am, Frogwatch wrote:
On Sep 3, 10:39 am, 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.
See Harry, not only do you not provide anything useful, you don't even
read my post. I will haul her out and remove the old strut.
Please do not reply to this thread unless you actually have something
useful to add.

Hmmm, ok, here's a weird thought, I can coat the strut with gold.
Seriously, I can put it in the sputtering system and coat it with a
few dollars of gold or platinum, both very high on the galvanic
series.
Even better would be graphite. I have some conducting graphite paint
that might work.
Dont gold coins immersed for centuries in seawater always come out
shiny?


So do watermelon seeds going through the digestive tract.