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Re: Try a bottom-paint...
By:Mark
Date: 11/23/2009, 7:02 pm
In Response To: Try a bottom-paint... (Dan Caouette (CSFW))

: Definitely only spray the two-pot stuff if you're equipped. They
: ARE worth the effort: better gloss and abrasion. They cure
: faster and need fewer coats than the one-pot paints/varnishes.

: If you are looking for a tough white coating for your hull,
: consider using a bottom paint designed for trailered boats
: (powered or sail). Crazy... I know. It only took me 5 years of
: building to figure that one out. I've had great luck with
: Interlux VC Performance Epoxy. It's a two-component epoxy-based
: paint. Very easy to roll and tip, brush or spray. It's
: epoxy-based so there are no nasty isocyantes like the urethanes.
: It cures fairly quickly and can be burnished. Only available in
: white. Nice stuff.

: Dan

As was mentioned earlier, most gelcoats available are poly and thus will not adhere to epoxy without a tiecoat (usually a VE resin gelcoat), which makes them a complete pain to apply. I'd also urge you to stay away from epoxy gelcoats completely; while they're extremely durable (hence why they're used inside production molds), they have no UV resistance and will start to deteriorate very quickly in sunlight. Don't believe the hype about UV inhibitors in epoxy, they're not good enough to protect underlying layers and you'll eventually end up refinishing your boat or throwing it out. I'd also stay away from gelcoat because it's almost impossible to achieve a factory-finish when applying it (even with a spray gun) to a boat... It's designed to be applied inside the mold and really will not give a satisfactory finish without a TON of work when sprayed on the boat directly.

Two part polyurethane is not that difficult to apply provided you have equipment to spray it. I've had excellent results spraying both one- and two-part poly through a conventional gun with a 2.2 mm tip at about 60-80 PSI. If you do go the paint route, make sure you test the adhesion between the paint and your surface before doing the whole boat. Somewhere on the WEST website there's a good article about how to do this (essentially cut cross hatches in surface and try peeling off with tape). You may need a primer to get satisfactory adhesion, or you may have to apply a new surface coat of epoxy to get some chemical bonding of paint to hull. Anyway, good luck!
--Mark

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