I have a 1988 custom built aluminum hull sloop that I had sand blasted below the water line to remove years of antifouling paint buildup, and to start fresh with new and also see what condition the hull would be in and if it would warrant any metal work. For the most part, faring compound still remains and I can see the dings and dents that it has received over time. I would like to use Bondo for the deep fills that I probably won't be able to push out(1/4 inch alu thickness) and then use a good epoxy faring compound for the top. Would this approach be acceptable prior to finish coating or would there be a better way.

John

On Sun, 15 Mar 2009 23:39:46 +0000, EASI54
wrote:


I have a 1988 custom built aluminum hull sloop that I had sand blasted
below the water line to remove years of antifouling paint buildup, and
to start fresh with new and also see what condition the hull would be in
and if it would warrant any metal work. For the most part, faring
compound still remains and I can see the dings and dents that it has
received over time. I would like to use Bondo for the deep fills that
I probably won't be able to push out(1/4 inch alu thickness) and then
use a good epoxy faring compound for the top. Would this approach be
acceptable prior to finish coating or would there be a better way.


Bondo has a poor track record for long term adhesion in a marine
environment, better to use an epoxy based fairing compound for
everything.

Bondo is hygroscopic (absorbs water and swells), and also doesn't adhere
very well below the water line. Instead, use a good epoxy like West Systems
with one of their fairing fillers.

Tom Dacon

"EASI54" wrote in message
...

I have a 1988 custom built aluminum hull sloop that I had sand blasted
below the water line to remove years of antifouling paint buildup, and
to start fresh with new and also see what condition the hull would be in
and if it would warrant any metal work. For the most part, faring
compound still remains and I can see the dings and dents that it has
received over time. I would like to use Bondo for the deep fills that
I probably won't be able to push out(1/4 inch alu thickness) and then
use a good epoxy faring compound for the top. Would this approach be
acceptable prior to finish coating or would there be a better way.

John




--
EASI54

NEVER, ever use automotive fillers. They are hygroscopic and will fail with
certainty. Use epoxy and micro balloons for filler. Mix to the consistancy
that will not sag. Do not over fill. Plan to fill more than once. Use
Stanley composition files when the mix is rubbery to get close. Fill again
and finish when cured with orbital sander. Be careful. When cured, the
filler is harder than the aluminum. Don't forget to use an etching primer
for aluminum.
Steve

"EASI54" wrote in message
...

I have a 1988 custom built aluminum hull sloop that I had sand blasted
below the water line to remove years of antifouling paint buildup, and
to start fresh with new and also see what condition the hull would be in
and if it would warrant any metal work. For the most part, faring
compound still remains and I can see the dings and dents that it has
received over time. I would like to use Bondo for the deep fills that
I probably won't be able to push out(1/4 inch alu thickness) and then
use a good epoxy faring compound for the top. Would this approach be
acceptable prior to finish coating or would there be a better way.

John




--
EASI54

Thanks Steve for your input regarding hydroscopic properties in Bondo. I was thinkingof an economical solution to sanwich in between the layers of epoxy but it isn't worth taking the chance. West Marine is an option but before I go that way maybe Progressive Epoxy polymers might have an answer that can save me bucks. Do you have any source recomendations?
Thanks again.
John

On Mar 16, 3:45 pm, "Steve Lusardi" wrote:
NEVER, ever use automotive fillers. They are hygroscopic and will fail with
certainty. Use epoxy and micro balloons for filler. Mix to the consistancy
that will not sag. Do not over fill. Plan to fill more than once. Use
Stanley composition files when the mix is rubbery to get close. Fill again
and finish when cured with orbital sander. Be careful. When cured, the
filler is harder than the aluminum. Don't forget to use an etching primer
for aluminum.
Steve

"EASI54" wrote in message

...



I have a 1988 custom built aluminum hull sloop that I had sand blasted
below the water line to remove years of antifouling paint buildup, and
to start fresh with new and also see what condition the hull would be in
and if it would warrant any metal work. For the most part, faring
compound still remains and I can see the dings and dents that it has
received over time. I would like to use Bondo for the deep fills that
I probably won't be able to push out(1/4 inch alu thickness) and then
use a good epoxy faring compound for the top. Would this approach be
acceptable prior to finish coating or would there be a better way.

John

--
EASI54

Good epoxy is a joy to use compared to Bondo although it is more
expensive.

I do not have a special source for epoxy or micro balloons, but they are
standard commodities with dealers that sell fiberglass and the like. There
are different sizes of microballoons as well. Ask the seller for their
recommendation for your application and you won't go wrong. Remember to sand
the aluminum immediately before applying the filler. Fill as soon as
possible after sanding.
Steve

"EASI54" wrote in message
...

Steve Lusardi;702834 Wrote:
NEVER, ever use automotive fillers. They are hygroscopic and will fail
with
certainty. Use epoxy and micro balloons for filler. Mix to the
consistancy
that will not sag. Do not over fill. Plan to fill more than once. Use
Stanley composition files when the mix is rubbery to get close. Fill
again
and finish when cured with orbital sander. Be careful. When cured, the

filler is harder than the aluminum. Don't forget to use an etching
primer
for aluminum.
Steve

"EASI54" wrote in message
...-

I have a 1988 custom built aluminum hull sloop that I had sand
blasted
below the water line to remove years of antifouling paint buildup,
and
to start fresh with new and also see what condition the hull would be
in
and if it would warrant any metal work. For the most part, faring
compound still remains and I can see the dings and dents that it has
received over time. I would like to use Bondo for the deep fills
that
I probably won't be able to push out(1/4 inch alu thickness) and then
use a good epoxy faring compound for the top. Would this approach be
acceptable prior to finish coating or would there be a better way.

John




--
EASI54 -

Thanks Steve for your input regarding hydroscopic properties in Bondo.
I was thinkingof an economical solution to sanwich in between the
layers of epoxy but it isn't worth taking the chance. West Marine is an
option but before I go that way maybe Progressive Epoxy polymers might
have an answer that can save me bucks. Do you have any source
recomendations?
Thanks again.
John




--
EASI54

Steve Lusardi wrote:
I do not have a special source for epoxy or micro balloons, but they are
standard commodities with dealers that sell fiberglass and the like. There
are different sizes of microballoons as well. Ask the seller for their
recommendation for your application and you won't go wrong. Remember to sand
the aluminum immediately before applying the filler. Fill as soon as
possible after sanding.
Steve

--------
we sell microspheres in different sizes (for about $5 a quart) go to
www.epoxyproducts.com/2_fillers.html - paul
--------------------


"EASI54" wrote in message
...

Steve Lusardi;702834 Wrote:

NEVER, ever use automotive fillers. They are hygroscopic and will fail
with
certainty. Use epoxy and micro balloons for filler. Mix to the
consistancy
that will not sag. Do not over fill. Plan to fill more than once. Use
Stanley composition files when the mix is rubbery to get close. Fill
again
and finish when cured with orbital sander. Be careful. When cured, the

filler is harder than the aluminum. Don't forget to use an etching
primer
for aluminum.
Steve

"EASI54" wrote in message
...-

I have a 1988 custom built aluminum hull sloop that I had sand
blasted
below the water line to remove years of antifouling paint buildup,
and
to start fresh with new and also see what condition the hull would be
in
and if it would warrant any metal work. For the most part, faring
compound still remains and I can see the dings and dents that it has
received over time. I would like to use Bondo for the deep fills
that
I probably won't be able to push out(1/4 inch alu thickness) and then
use a good epoxy faring compound for the top. Would this approach be
acceptable prior to finish coating or would there be a better way.

John




--
EASI54 -

Thanks Steve for your input regarding hydroscopic properties in Bondo.
I was thinkingof an economical solution to sanwich in between the
layers of epoxy but it isn't worth taking the chance. West Marine is an
option but before I go that way maybe Progressive Epoxy polymers might
have an answer that can save me bucks. Do you have any source
recomendations?
Thanks again.
John




--
EASI54