G-Plasticoat Anybody?

[Mark Hughes]

Is anybody familiar with a product called G-Plasticoat? I stumbled upon it on the web at http://www.g-plasticoat.com/, and it sounded intriguing. I emailed them with some questions, and here is what they answered:

"Thank you for your interest in G-Plasticoat. Yes, this product

has been proving itself as a great protectant for marine applications.

It is undergoing extensive testing in this area and has been protecting

boats from mold & mildew, oxidation, etc... It is paintable, however,

it is highly suggested that the surface appears as desired before

the application of G-Plasticoat; this is mainly used for a top coat

and only protects the paint that it covers. I am unsure what "checking"

in plywood is - but if it means the plywood surface peels due to

moisture; Yes, this will prevent "checking" (Let me know if this

is what you were referring to). It is durable and flexible, will

not crack, chip, or peel, and withstands many weather damages.

Apply with a lint-free cloth, synthetic brush or roller, or air-less

sprayer (keep good product control). Watch for drips and excessive

foam (most will collapse). Be sure surface is clean, dry, free

of wax and oil, and appears as desired before application. Keep

water away from surface until cured. Apply until a good top coat

is achieved. If any gouges or deep scratches result from use, just

apply more G-Plasticoat to the area."

My thinking was this could be an alternative to glass/epoxy, particularly for the topside, cockpit and cabin. I have asked if I can get a sample to try out, but if any of you have knowledge of or experience with this product, I would love to hear what you think.

[Barry Pyeatt]

Don't think it would substitute that well. I dont' think the rep you talked to understands what checking is in plywood.

It is the expansion and contraction of the different layers of grain, between the softer layers and the harder layers. This occurs with changes in humidity as well as dramatic temp changes. It gets compounded with freezing temps as the moisture in the wood expands as it freezes and that is at different rates between the growth rings. That expansion and contraction causes the paint, finish to take on a cracked appearance over broad expanses of surface, and moisture can enter thru the cracks.

So with plywood, particularly softwood plywoods (Fir, Pine, etc.) it is particularly noticeable. I'm sure the product offeres a good deal of protection and will present a nice finish. But like epoxy, I doubt very much that it would prevent checking. Only fiberglass (for the most part) in these applications prevents it.

You could clear coat paint with clear urethane and have a really good protection for the paint as well...until the UV factor wore out. Mildicides and fungicides added to your paint will protect against mildew and mold forming to a great extent. But ventilation is the biggest factor there. Keep the moisture out of the closed in areas and no mold or mildew will form.

I'm always interested in new solutions to old challenges. But I don' think a plastic topcoat is going to prevent the underlying challenge of checking.

[Mark Hughes]

Thanks for your reply, Barry. Since they are being kind enough to send me a sample to try out, what would you suggest for a test to simulate the contraction and expansion that would normally occur over time?

[Barry Pyeatt]

Paint up a panel, both sides, small enough that will fit in a freezer compartment. Apply their coating to one side of the panel and after it cures, put it in the shower with the curtain closed and hot steamy water flowing around but not on it. Keep it there for some time to take advantage of the high humidity. Then place it in the freezer and leave it there for a few days. Repeat the cycle several times and then see what it looks like. It won't have the prolonged exposure to high humidity but should indicate what is happening.

Remember this is only a thin plastic coating that is applied over paint.

[Mark Hughes]

All right, that's what I'll do. I was thinking of putting the plasticoat directly on the wood and then painting over it. Maybe I'll try one each way and see if there is any difference in the results. Thanks for the suggestion, I'll report the results here if anyone is interested.

[Knut]

I am going to buy a gallon of the stuff and use it on the cast iron keel of my Balboa 20. The keel is partly a little rusted, so I will first brush away loose rust and then paint over with a rust-binder, also covering the rest of the keel for even color. The intention is to finally coat the whole thing with the Plasticoat for added protection. If this looks good after a while, I may even try the coat as a bottom "paint" (under the water-line), since growth seems to have trouble biting on the stuff.

I will also report on experience. It could have some interesting properties and the cost is quite reasonable as far as I can see.