The Rot Doctor


Subject: Rhinoguard vs old gelcoat
Date: Mon, 29 Jan 2001

1987 30' Sea Ray, badly deteriorated foredeck - why fight the gelcoat wars when the possible answer might be Rhinoguard (or some other type product) The gelcoat will never look like new again and why introduce the "slippery element" at this point on the boat? Please look into other alternatives for "look good but be reasonable about maintenance".


Interesting that you should ask about RhinoGuard. We concluded a while ago that a product like RhinoGuard, which is a high density polyurethane, would be a perfect product for sealing/waterproofing/strengthening fiberglass and wood decks. So we began researching what was there and available.

As it turns out, almost all of these high-density polyurethanes are formulated for heated spray application onto truck beds, large steel tanks and containers, building floors, and the like. But we finally did find some that can be brush or roller applied, and we have just completed Phase I of our testing on these and are preparing to put them on the market. They are TOUGH!

You have basically two choices: 1) A 100% solid polyurethane basecoat (Elastuff 120) covered with either a water-based acrylic/epoxy top coating (Rhino Top) or a really tough aliphatic polyurethane top coating (Elasta-Tuff™ 6000-AL-HS) (the basecoat is gray and the surface is gradually degraded by UV light -- just an appearance problem, not a strength problem, but this is why the Elastuff 120 is usually topcoated); or 2) Go straight to the aliphatic polyurethane topcoat (Elasta-Tuff™ 6000-AL-HS) and apply several coats, with some non-skid sprinkled onto the second to last topcoat. Both the Rhino Top and the Elasta-Tuff™ 6000-AL-HS are available in several stock color shades of gray and tan, as well as a medium-deep green and kind of a brick red.

The boat deck should be scuffed, thoroughly cleaned, and deep grooves filled with our Fill-It Epoxy Filler so they won't show when the coatings are applied. No prime coat is required if the glass is not too chalky. If it is, we have a special epoxy sealer (CPES) that goes on first.

The Elastuff 120 basecoat plus the Elasta-Tuff™ 6000-AL-HS would be about the toughest covering you could put on a deck. The US Navy uses the Elastuff 120 plus Rhino Top, and I understand that it is now somewhere aboard the USS Nimitz. The Elasta-Tuff™ 6000-AL-HS would also work well, as it is very very tough. The Rhino Top cannot be used alone, except as a kind of super porch paint. I wouldn't recommend it on fiberglass.

Have I confused you? Prices for these products are as follows:

Elastuff 120 $157.18* for 2 gallon unit (1:1 mix)
Rhino Top $40.69* per gallon (single component)
Elasta-Tuff™ 6000-AL-HS $124.96* per gallon

That's the bottom line on these kinds of products. If I had your boat I would look hard at the Elasta-Tuff™ 6000-AL-HS, because it would be a single product coating process. It produces a matte-gloss finish. Coverage rate is about 1 gallon per 100 sq feet, and you would need at least 2 coatings, and 3 coatings would be better. You gotta like white, light grays, light tans, or green and red, though! They are not available in other colors unless it is a custom mix, which would require a very large order and some extra charges.

If you have questions, come on back and we will answer them.


*Current prices can be found on our Product Information page.