43' aluminum hull repair
 

My friends 43'aluminum houseboat has developed some severe pitting on
the bottom. Since he bought it, it has been in a lift and will continue
to be - the pitting existed before he bought it. Some of the hull is
like new but bad pitting where there has been barnacles.

We are having it hauled and sandblasted Mon. The yard also has a
treatment which they guarentee will remove any trace of salt in the
aluminum pores. I expect we will find too much pitted area to
economically weld.

Question - how well will expoxy impregnated fiberglass mat adhere to a
well prepaired rough surface ?? Patches would be 1 to 2 ft. sq. Boat
does 8 mph max and we would be happy with a 10 year life to the
repairs. The longest the hull will be in (salt) water will be 1 week
and then back in the lift. BTW we will be painting with 3 coats of
epoxy paint after repairs.

43' aluminum hull repair
 

There is no free lunch. Welding in new metal is faster, better and cheaper.
Problem sounds like electrolosis. Salt isn't the problem. Disimilar metals
is.
Steve

wrote in message
oups.com...
My friends 43'aluminum houseboat has developed some severe pitting on
the bottom. Since he bought it, it has been in a lift and will continue
to be - the pitting existed before he bought it. Some of the hull is
like new but bad pitting where there has been barnacles.

We are having it hauled and sandblasted Mon. The yard also has a
treatment which they guarentee will remove any trace of salt in the
aluminum pores. I expect we will find too much pitted area to
economically weld.

Question - how well will expoxy impregnated fiberglass mat adhere to a
well prepaired rough surface ?? Patches would be 1 to 2 ft. sq. Boat
does 8 mph max and we would be happy with a 10 year life to the
repairs. The longest the hull will be in (salt) water will be 1 week
and then back in the lift. BTW we will be painting with 3 coats of
epoxy paint after repairs.

43' aluminum hull repair
 

Question - how well will expoxy impregnated fiberglass mat adhere to a
well prepaired rough surface ?

Epoxy does not adhere to oxidized aluminum, which is to say, any aluminum
exposed to air, even for seconds. So you cannot just sandblast it and
expect it to bond.

I have heard of a technique where you first apply a thin epoxy layer to the
metal, and then immediately brush with a stainless brush through this
layer, which exposes fresh elemental aluminum but protects it from the air.
This is reputed to work but I have no experience with it myself. And I
don't know how well it holds up when immersed.

43' aluminum hull repair
 

Hi.

I have been working on cars and light comm vehicles for years, during
this time I have used a product called Scorpion coatings, for truck bed
liners, having coated my own truck bed with this I can say that it is
bloody marvelous, you would find it very difficult to damage it.

Since the coating is applied direct to the surface, there is no air
gaps so therefore no corrosion.

This coating can be used for all sorts of applications, truck beds,
workshop floors, flat roofs etc.

I have used it on the floor in the deck area of my boat, but not on the
outer hull as mine is ok.

Check out the web site, you can allways ask them if it would work.

There are lots of similar companys doing the same thing. I guess they
are all basicly the same?? You can find adverts in any 4x4 mag.

Web site, http://www.scorpioncoatings.com/

Regards
Slim

43' aluminum hull repair
 

Bob wrote:
wrote:
We are having it hauled and sandblasted Mon

Question - how well will expoxy impregnated fiberglass mat adhere to a
well prepaired rough surface ??

Hi:

The BIG question is why did you get that pitting to begin with?
Something is going one that aint right.

Maybe time to change marinas or put another 30 pounds of zincs on.
Can you explain the term "Reverse Polarity"? If
not..................

Research "Catholic Protection" or "Electrolysis " or "dissimilar metal"
or "metal nobility"

There are some really smart people who read this BB.
Read
Learn
THEN ask!
Life Long Learner Bob

43' aluminum hull repair
 

http://www.armacoatings.com/marine.html


wrote in message
oups.com...
Hi.

I have been working on cars and light comm vehicles for years, during
this time I have used a product called Scorpion coatings, for truck bed
liners, having coated my own truck bed with this I can say that it is
bloody marvelous, you would find it very difficult to damage it.

Since the coating is applied direct to the surface, there is no air
gaps so therefore no corrosion.

This coating can be used for all sorts of applications, truck beds,
workshop floors, flat roofs etc.

I have used it on the floor in the deck area of my boat, but not on the
outer hull as mine is ok.

Check out the web site, you can allways ask them if it would work.

There are lots of similar companys doing the same thing. I guess they
are all basicly the same?? You can find adverts in any 4x4 mag.

Web site, http://www.scorpioncoatings.com/

Regards
Slim

43' aluminum hull repair
 

mark wrote:

http://www.armacoatings.com/marine.html


== http://www.sulzermetco.com/

'=hot=' , thermal 'alum' spray ...
refreshes 'alum' jet engine cast/sheet metal parts.

akin to rebuilding crankshafts ...

Ed

43' aluminum hull repair
 

mark writes:

http://www.armacoatings.com/marine.html

Hmmm. A soft, rubbery, waterproof coating made from polyurethane that takes
7 days to set.

Sounds like 3M 5200 to me.

43' aluminum hull repair
 

Do you know how to read.
Boat Hulls: Arma Coatings provides a lightweight yet extremely hard, durable
coating for aluminum, fiberglass and wooden boats. It sets quickly and
allows you to hit the water in 2-3 days. It withstands the torture of
remote, unimproved launch areas, hidden water hazards like rocks, logs and
branches, and a variety of beaching environments. Use it as a keel guard or
full bottom protection to prolong the life and beauty of your boat.



"Richard J Kinch" wrote in message
. ..
mark writes:

http://www.armacoatings.com/marine.html

Hmmm. A soft, rubbery, waterproof coating made from polyurethane that
takes
7 days to set.

Sounds like 3M 5200 to me.

43' aluminum hull repair
 

mark writes:

Do you know how to read.

Your top-posting makes it difficult, but I was only quoting the site you
cited. Don't blame me.