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Re: Epoxy: Gelcoat instead of paint? Or 2-pack?
By:Bill Hamm
Date: 11/22/2009, 6:22 am

: Hi,

: I am building a Point Bennet (18' S&G sea kayak) and was going
: to laminate venerrs onto the hull (to make it pretty!) but have
: decided to go with a painted exterior, as this will be a kayak
: used more for serious trips (well, to me) and overnighters, so
: for safety, etc I wanted to paint in light colours (as I paddle
: where there's lots of powerboats).

: So, the obvious method is to 'glass then paint with white (for
: example). But I wondered if anyone has used gelcoat - the
: coloured epoxy coating used as the outer layer in
: 'glass/carbon/kevlar production boats? This is essentially an
: epoxy compund which can be coloured. Fors a skin over the glass.

: Does this just add uneccessary weight? Or due to the stiffness of
: gelcoat would it crack when applied to ply due to the ability of
: the wood to bend/absorb impacts? Not worried about the upkeep
: (except cracking) as I repair 'glass boats too.

: Is there much difference between this and a painted surface? Could
: I apply the gelcoat as a layer directly to the wood, then 'glass
: over it? Would I want to?!

: And, if gelcoat isn't a viable option, my secondary question is -
: whilst 2-pack paint is (apparently) harder to apply, is it a
: much better/tougher outer coating than standard marine enamel?

: Thanks - apologies for all the questions at once! Just wondering is
: gelcoat is possible & worth it.

: Regards,
: Darren
: Melbourne, Australia

The grand majority of gelcoat is polyester based and thus not compatable (you can apply epoxy over polyester, just not the other way around. There are a few epoxy gelcoats but they are fairly rare. They are also quite heavy and not designed to be applied to the outside of a boat, rather normally appled to the inside of a mold and get their smooth texture (or lack of it) from the mold surface. Would need a considerable amount of sanding and polishing to get it smooth done on the outside.

The two part paints are quite durable and other than the water based ones are extremely toxic so need specialized gear to apply them, the water based ones are only mildly toxic. They normally have to be sprayed and require a supplied air respirator to allow for safe spraying. Best left to professionals. That said, many auto body shops have the ability and tools to do this and can do it at a fairly reasonable price.

I still prefer single part marine paints, single part urethanes. Big advantage other than you can easily apply them is they are easy to fix if damaged. Some of the two part paints are very tricky to repair.

Bill H.

Messages In This Thread

Epoxy: Gelcoat instead of paint? Or 2-pack?
Darren -- 11/22/2009, 5:23 am
Re: Epoxy: Gelcoat instead of paint? Or 2-pack?
Bill Hamm -- 11/22/2009, 6:22 am
Re: Epoxy: Gelcoat instead of paint? Or 2-pack?
Darren -- 11/22/2009, 6:36 am
Try a bottom-paint...
Dan Caouette (CSFW) -- 11/22/2009, 6:46 am
Re: Try a bottom-paint...
Mark -- 11/23/2009, 7:02 pm