I want to finish my freshly painted, poly surfboard with a clear top coat to ensure waterproofness, durability, anti-yellowing and a matte finish. I used multiple, light coats of an **oil-based **Rust-Oleum product (Rust-Oleum Universal All Surface Spray Paint) as my paint and hand sanded with 200-grit after all coats dried. Standard surfboard finishing involves a hot coat, gloss coat, and then sanding/buffing, but these tend to yellow after a short period of time.
I’ve scoured the internet for answers and have come across a number of possibilities, including:
Marine 2-part LPU's
Industrial 2-part Polyurethane
Automotive 2 Part PU-Clear Coats
Water & Solvent-based acrylic and PU
In short, I’m lost in it all. I don’t have the technical knowledge to distinguish between these coats nor the time to study up. So, what UV resistant finish** **could I use over the oil-based paint to protect and water-proof while achieving the matte finish seen on newer boards?
WR-LPU contains UV absorbers and will not yellow or lose gloss for years, depending on exposure. WR-LPU kits contain a can of paint and a bottle of crosslinking material.The paint by itself cures to a very high-quality coating without the crosslinker. However, adding the crosslinking material produces a tougher and more durable film. It will be more chemical and fuel resistant, have better gloss retention and generally last longer. use cleas gosss or matte finish. Need an appropriate size needle for sprayer gun for viscosity of urethane. Can cut with 10% water. Easy water clean up. 3 coats each side. When finish sanding I start and stop at 1000 grit foam pad. Takes less than 10 minutes to sand top and bottom. Board needs to be water tight. No spay urethane with help with a improlerly sealed board. Your board should able to surf before spraying. A sanded board to 120grit is fine before starting. Hot day for spaying makes a qjuicker job. I spray deck first and after dry to touch I flip and do bottom andlet cure over night on racks. Any marks on deck should sand out with 1000g foam pad easily.
I use a similar product from woodcraft that does the same job but no cross link needed and half the price.
To double-check, is it ok to apply the WP-LPU directly on top of the oil-based Rust-Oleum paint? When reading through the instruction manual for System Three’s product, I did not see that as an option.
I do not have access to power tools. Can I adequately hand-sand before/after applications using a 120 grit/1000 grit sanding sponge? In that same vein, can I apply using a brush rather than a spray gun?
Will 1 quart of the WR-LPU do the trick or will I need an entire gallon?
The board is a 7-year-old 6’ GSI 7S Superfish (polyester) which was already finished prior to painting. I merely sanded down the poly resin top-coat with 100 grit and 120 grit paper and painted over that. Does that make sense?
Thanks for the claification. Knowing where you are at with your build you have lots of options. Pics would help still. So you are doing this for artwork display or to surf every day? Any whoooo… You don’t own a dick brewer or rick holt classic so you seem to be spending lots of money on someithing I hope is of personal sentimental value and not actual value. What I am about to say will save you hundreds of dollars and tons of hand sanding time since you are tool less. Rattle Can gloss, crystal clear acrylic. Don’t worry about the uv protection,. 3 cans of the stuff will be $15 with no sanding necessary. Light coats, and many of them. FIRST hit with 120 or higher grit on paint job prior to carefully spraying.
Another option is to really decide what you want for coverup paint job. Sand current paint job off and spray with rattle can acrylic. Hit with 120 or higher and clear gloss acrylic.
Another option is too difficult tool less. Colored resin to improve looks or hide repairs.
Pics of huge dings reapaired. and camo coverup with rattle can acrylic. They sprayed urethane because it s eaiser and less of a hassle cuz I have the equipemnt. Rattle can gloss clear acrylic would have workded also.
Thank you for another detailed response. I do plan on surfing this board. I’m an east-coast student, so I can’t justify purchasing a new board (and don’t have the cash to do so), so I figured ‘renewing’ my old one was the best alternative. So far, I’ve repaired a few dings/chipped tail and have sprayed a solid base coat, spending about $70 on materials.
I’ll pick up some of Krylon’s “Crystal Clear Acrylic” spray and use that
