I have been using Behr low lustre on a couple of my epoxy boards to seal them. Then I polish/burnish with a grey scotchbrite. I still get some marks from this. Do sanded production boards have any type of scartches or marks in them? I have recently got the oppurtunity to start making sups for a living and I am wondering how immaculate is a sanded coat? I sand out the final coat to 320, then i spray the acrylic concrete sealer. But it always has MANY fish eyes noticable to both the eye and hand. Do most shops have a super clean spray booth to lay on this finish? I have no choice to take a scotchbrite to it but it always leaves noticable marks. I have tried by both hand and by an orbital sander. I do like the feel of it after I am done but I dont like the look of it. Maybe I am super picky. I have tried even wet sanding my boards with the super expensive 3M wet paper 320/500 and still see very noticable scratch marks that are iniform with the direction of my hand movement. Ideally i would like to just spray on the finish and leave it.
that is the problem with epoxy.
You can gloss and polish like poly,
then theres the bonding issue.
The cheap Chinese stuff use a spray laquer then buff with sureluster with a polishing wheel.
But they do shine up nice.
Acrylic will show all scratches left by sanding.
Fine sanding is the key.
With epoxy I go 180-220-320-400.
If you leave deep scatches from heavier paper, they must be removed with finer sanding.
Try the laquer thing.
Smelly but effective.
Best spray finish comes from the car paint guys (urethane). A friend of mine paid a paint and body shop to clear coat a 9’8 SUP and they charged him $100. He was gonna wetsand and polish it but it looked OK with just a bit of orange peel. I think people get carried away with all this wetsand polish stuff.
Amen. Give it a nice mirror shine so it can be waxed on one side and scuffed up with coarse beach sand on the other.
Don’t spray the Behr sealer. It does make a differance. Wipe it on. These types of sealers are designed to be wiped on. If they were meant to be sprayed the manufacturer would include additves that would make it spray better and no fish eyes. Barry is right about epoxy and lacquer finish. That is what Thailand and China do. Noxious, but looks great, until it begins to yellow a couple of years down the road. An addendum; Spray work. If you are going to spray anything on a sanded surface take these percautions after sanding and before spraying finish. Inspect the sanded board for imperfections use a light close to the surface and inspect carefully for swirl marks and scratches. Blow the sanded board of both sides and wipe down with an automotiive wipe like those used in an auto body shop. If you are going to be doing this for a living; invest in a small static remover( about $100). This helps eliminate static dust particles from your sprayed surface. Static on the board will attract dust… A source of imperfections and fish eyes Set up a spray room and keep it as dust free as you can. I did lots of ding repair on sailboards on Maui and had gool luck using spray cans of acrylic lacquer from Home Depot for minor dings. Sprayed alot of boards with automotive clear coat( which was two-pac back then) You also need a compressor with a 40-60 galon tank so it can stay up with you. Seems like a big deal, but once you’re set up and doing alot boards it’s the best way to go. There are additives that will reduce fish eyes. They’ve made 'em for years and they can be found at auto-body supply shops and even some paint stores. Wipe on sealer for a sanded board is a great finish and I’ve had very good luck with “secret sauce”. Never a fish eye wiped on.
PS---- Barry’s also right about the fine sanding on epoxy. It’s easier in my opinion to get the scratches out of Poly than it is Epoxy. You have to go to finer grits with Epoxy. And; Yes! You can almost always find swirl marks and sanding scratches in the average production board. Doesn’t mean they should be there, but they are. All the Scotchbrite pad is supposed to do is heat the sealer enough via friction to make it flow out and level. If you are getting sratches in the sealer from the pad; you are getting on it too hard. If you sand your hot coat to the point that it is scratch free. Blow off the sanded hot coat dust free and wipe on one or two coats of Berh. You shouldn’t even need to burnish with the pad. Use a grey pad it is finer than the maroon.
I’ve left the deck somewhat rough on some board lately since it gets covered with grime and because I’ve had a few complaints that the wax won’t stick, but sand the bottom to a semishine. But when you put it that way…
Flat finishes are the big thing with the custom car and chopper people. They have some new stuff that is unreal.Theey are flat clearcoats. And yes you need spray equipment. I saw a bike where they just sprayed the finish outside and didn’t use a spray booth.Came out nice. Just have to watch the weather.