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Default Remove or Not Remove Partially Cured Epoxy?

I am sure I will give the partly cured epoxy a bit more time to cure.
I am not particularly enthusiastic about removing it. But I will only
give it until the end of this month. You see. The temperature inside
the tent (where the boat is) is high. I don't believe cold temperature
has anything to do with this problem. Therefore, the chance is high
that the epoxy may never cure completely. I can afford to wait because
I have something else to do anyway. But at the end, I have a feeling
that I will have to remove it.

I don't quite understand why I should use Dynel instead of regular
fiberglass cloth. Is there any particular reason why Dynel is better
suit for this situation? Thanks in advance for any follow-up info.

Glad to learn that I can use a belt sander instead of a surface
grinder. I already has a belt sander with coarse sanding belt. This
means I am all set if I need to use a power tool to remove the partly
cured epoxy.

Jay Chan


Ron Magen wrote:
Jay,
It's kind of like hypothermic death in the cold climates . . . 'Your not
dead until you are WARM and dead . . .'.

Absolutely - there IS a chemical structure difference between Poly and
Epoxy. However if time is no problem I wouldn't limit the 'wait time' to a
week. In addition I would 'add energy to the reaction' by applying heat.
There are a couple of simple ways to do this, depending on the area in
question. a}Throw a tarp over the area, then an electric blanket set on
'LOW' or 'Medium'. b} set up a 'long board' or 'panel' with several simple
sockets for light bulbs. Place it SAFELY & CAREFULLY in the compartment
below the deck area. Use 100w or less bulbs. {I use arrangements like this
when building in the colder months - with the hull upside down and a tarp
thrown over & hanging down to trap the heat, and with a 'drop cord' in a
Styrofoam 'cooler' to keep the epoxy components warm}.

Once there is NO MORE apparent hardening {after a total of about 30-days or
by 'scratch test'}, then I'd make my decision. If it IS 'sandable' {even if
you have to do it gently with course paper to prevent 'gumming'} I'd apply a
thin coat of CORRECTLY mixed epoxy, then lay in a layer of Dynel. This is
NOT like f'glass. It WON'T become clear, but will still look somewhat white.
Also without several more coats of epoxy it won't be perfectly smooth.
However these are NOT BAD points for a white deck - it won't show and will
add traction. PLUS the stuff is VERY abrasion resistant.

On the remark about the 'surface grinder' . . . Yes, this is a very useful
tool - I have three of them. In your case I would not choose this first -
look at the smaller, 'straight-line' BELT SANDERS with adjustable speed.
MUCH more controllable, much more sanding material in contact with the
surface, less tiring in use, and an all-around more multi-functional tool.

Regards & Good Luck,
Ron Magen
Backyard Boatshop



wrote in message
ups.com...
Thanks for pointing this out. Sound like I have a hopeless case on my
hand. OK, I just have to treat it as a learning experience.

Jay Chan


derbyrm wrote:
I think there's some confusion between polyester resin and epoxy.

As someone else pointed out, with polyester, the hardener is a
catalyst/accelerator and the resin will eventually cure.

As I understand epoxy, it is the combination of the chemicals in the

resin
and those in the hardener. Too few of the hardener molecules and you'll
never end up with actual epoxy, only with a slurry of cured epoxy and
uncured resin molecules looking for their mates. It will not be very
strong.

I'd suggest you start scraping.

Roger (sorry)

http://home.insightbb.com/~derbyrm

wrote in message
oups.com...
Glad to hear that there is some hope. OK, I will wait a week or two

to
give it a chance. Meanwhile, I can always work on something else or

go
fishing on a rental boat. If after two weeks my finger nail still can
make a dent on the epoxy, I will remove it.