On Jul 8, 8:54*am, " wrote:


Hi Tom,

You caught me in an usually benovolent and kind mood today........

Below is a post from 2005 that may be of help:


Hello:
Any thoughts on this.
Chainplates are a source of leaks and equal source of debate on how
to
fix the leak.
Some people say use polysulfide because if you use 3M5200 you'll be
tearing your boat apart to rebed plates in a few years.
Others say the reasons why plates leak is because polysulfide do not
have required strength. The only way to solve plate leaks is to use
3M5200. Why? It has a much stronger bond.
Others say that 3M5200 loses its bond eventually and it too will
leak.
Only this time the boat owner has a major problem removing the old
adhesive to rebed.

Here is the question....... Why would 3M5200 bond fail?


I called 3M tech people and they sent Tech Data Sheet (effective:
12/1/2004). Interesting data.
I also called Royal Adhesive and received data for Silaprene.
This is what I read.


Stainless to Stainless Overlap Sheer Strength
3M5200.........352 psi
Silaprene......488 psi


Interesting.


What about temperature. I was painting my garage last summer. Ambient
temp was 94 degrees F. I hung a thermometer on the side of the garage
in direct sun. Temp of garage wall was 150 degrees F. OUCH!


How hot do chainplates and decks get in many parts of the world
during
the hot season? 130-150-180F? Just a guess. How does temperature
effect
plate adhesive bond? I got more TDS stuff.


3M data: (Service temperature -40F to 190F) "Heat resistance-Due to
the decreased value in bond strength at elevated temperature, we do
not
recommend use of this product above 190F."


Silaprene data: (Service temperature -60F to 250F) " Heat
resistance-No significant loss of bond strength until 300 degrees F."


Elevated Temperature Shear Strength
3M5200......................(70F = 240psi) (150F = 176psi) (190F =
139psi)Teak
test substrate.
Silaprene.............(70F - 250F)No significant shear strength loss.
READ THIS AGAIN !


Question. Could 5200 fail because deck and plate temperatures reduce
its bond strength?


Has anybody used Silaprene?


Comparing data each company supplied says Silaprene has greater bond
strength than 5200 on stainless steel and keeps its strength at
temperatures when 5200 begins acting like butter (exaggeration).


Ideas about the deck temperatures causing 5200 failure
Should I use Silaprene to rebed my chainplates "forever?"

Bob

On Jul 8, 10:31*am, wrote:
"Silaprene" is the name for about 200 different formulas, some of
which may react badly with what you are bonding, or have other issues.

The tube just says "Silaprene North America's Premier Adhesive/
Sealant" and they list the polymer base as Polychloroprene. There
aren't that many "Silaprene" adhesive/sealant products but there are
more than I'd have guessed from looking at the package.
http://www.industrialadhesives.com/b...?division_id=4 for a list.
As for the rest, could be, that's why I'm asking for experience.

-- Tom.

On Jul 9, 8:43*am, wrote:
...
Maybe they count each different packaging size as an "offering, and I
misinterpreted it.

Yeah, I'm not sure what they are saying but if you click on the
"brochure" link it only shows a hand full of "Siliprene" tubes of
which I think 7 are adhesive/sealants.

-- Tom.

On Jul 9, 8:18*am, Bob wrote:
On Jul 8, 8:54*am, " wrote:

Hi Tom,

You caught me in an usually benovolent and kind mood today........
...

Thank you very much. Nice post. Kind of you to re-send it.

-- Tom.

On Jul 9, 8:06*am, "Roger Long" wrote:
...
Do you know a source for Silaprene? *I was unable to find it anywhere other
than wholesale quantities except from Atkins Hoyle.

Don't know if these help but google shopping gives:
http://www.google.com/products?hl=en...-8&sa=N&tab=wf

or

http://tinyurl.com/6xn5xw

--Tom.

On Jul 10, 3:35*am, wrote:
...
Just the same, I know quite a few folks who thought all "Silicone" was the same,
and they bought their's at Home Depot to save a few bucks. OOPS! The home
version releases ACID as it cures. Pretty hard on boat hardware.

I think I get your point, and that's why I've been asking for reports
from users. Still, the 3M "Marine" silicone sealant that I bought at
West Marine just a few months ago was acid cure and double the price
of hardware store too... And, FWIW, 5200 releases solvents which may
include toluene, heptane and acetone. I'm still waiting for the
adhesive / sealant that sticks to everything, melts nothing and cures
in just the time needed... I don't know if this Silaprene stuff is it,
but the ability to stick to unprimed metal and other interesting
properties (see Bob's post) could make it a useful addition to my bag
of less than ideal goos.

-- Tom.

On Jul 10, 7:30*am, " wrote:
On Jul 10, 3:35*am, wrote:
...

Just the same, I know quite a few folks who thought all "Silicone" was the same,
and they bought their's at Home Depot to save a few bucks. OOPS!

I think I get your point, and that's why I've been asking for reports
from users. *Still, the 3M "Marine" silicone sealant that I bought at
West Marine just a few months ago was acid cure and double the price
of hardware store too...

My advice is spend a few days and become knowldegable sealant-adhesive
user. It took me nearly a month of calls to tech guys, reading
Technical Data Sheets, crusing websites to get a good understanding.
WM....and anyother retail boat store. They will carry the product
that provides the most profit and is "most popular" for everybodys
use... You know, the fit all product.

Regarding silicon products. When I installed my polycarb fixed port
lights I had to use silicone. After a few weeks I narrowed a few
products down and started calling the manufactures. Then I called a
couple instate big city commercial window installers (Union Shops of
course). I chose a product used to "glue" 4'x8' windows in sky
scrapers and keep Lexan in place in high security prisons. The tech
guys refered to it as "structural silicone" It has the same density as
lead (JK). It was a Dow Corning product can t remember the #, maybe
DC-735???

What im getting at is the last place you may want to seek info is from
WM or other boaters........ Go to the experts and tell them the your
aplication n specs and see what happens.


*I'm still waiting for the
adhesive / sealant that sticks to everything, melts nothing and cures
in just the time needed...
-- Tom.

It s not going to happen........... get the right goo for the right
job. And always remember when you use "boat life" or a Universal Goo,
it will always be a compromise. Personally i do not want to compromise
my projects.
Fair winds and good gooing....
Bob

Bob wrote:
On Jul 10, 7:30 am, " wrote:
On Jul 10, 3:35 am, wrote:
...

Just the same, I know quite a few folks who thought all "Silicone" was the same,
and they bought their's at Home Depot to save a few bucks. OOPS!

I think I get your point, and that's why I've been asking for reports
from users. Still, the 3M "Marine" silicone sealant that I bought at
West Marine just a few months ago was acid cure and double the price
of hardware store too...

My advice is spend a few days and become knowldegable sealant-adhesive
user. It took me nearly a month of calls to tech guys, reading
Technical Data Sheets, crusing websites to get a good understanding.
WM....and anyother retail boat store. They will carry the product
that provides the most profit and is "most popular" for everybodys
use... You know, the fit all product.

Regarding silicon products. When I installed my polycarb fixed port
lights I had to use silicone. After a few weeks I narrowed a few
products down and started calling the manufactures. Then I called a
couple instate big city commercial window installers (Union Shops of
course). I chose a product used to "glue" 4'x8' windows in sky
scrapers and keep Lexan in place in high security prisons. The tech
guys refered to it as "structural silicone" It has the same density as
lead (JK). It was a Dow Corning product can t remember the #, maybe
DC-735???

snip
Bob
Perhaps the stuff you have in mind is Dow-Corning 795. I've used it
quite successfully to attach plexiglas deadlights.

--Alan Gomes

"Steve Lusardi" wrote:
I guess I do not understand your comment, as you did not include the basis
for the statement. I have used cases of the stuff and find 5200
extraordinarily useful.

Same here


wrote:
What it is NOT, is a GENERAL PURPOSE adhesive OR sealant. It should
never be used for deck hardware or fittings, as it can not be easily
removed without damaging the items it is bonding and sealing.

I agree with you, 5200 is not a GENERAL PURPOSE material. Guys like
you should not use it... Damaging deck hardware & fittings? WTF??!?

For the rest of us, 5200 is great. Shucks, 3-M makes a huge number of
very very useful products.

DSK

On Tue, 8 Jul 2008 09:54:30 -0700 (PDT), "
wrote:

A buddy handed me a tube of this stuff and gave me a little sermon on
its virtues compared to 5200. Apparently it is used in the auto
industry and it sticks well to metal. Has anyone here been using it
on boats and if so how's it holding up?

-- Tom.

Not directly addressing your question, and a bit outdated concerning
new products, but this might be useful when considering
adhesives/sealants for various boat applications.

http://www.boatus.com/goodoldboat/sealant.asp

--Vic