Hi all. Im in the end stages of building a new shortboard for a trip to bali in may. Its all finished, except for the final gloss coat. Im more concerned about weight over a glossy finish. I have both gloss resin and lam resin/surfacing agent. Im essentially trying to get the thinnest/lightweight coat possible, just to cover some burn throughs. Could i use lam resin and heat it in water to get the thinness of the gloss resin, or am i better off just using the gloss resin? And i have never used gloss resin before, but understand that it flows much easier than lam/sanding resin, so how much gloss resin would normally be used for a 6’4" shortboard?
If it’s just to “cover some burn throughs” why don’t you just spot treat them with a dab of resin instead of recoating the whole board? Warming up lam resin will thin it out a bit, but i don’t think it will be the same as gloss. I’ve used this and not had any problem
IDK ABOUT ANYONE ELSE BUT I HAVE FOUND THE AMOUNTS IN THE CHART ABOVE TO BE A GOOD BIT OVER CALCULATED. I USUALLY GO WITH THE MINIMUM AMOUNT AND STILL HAVE LEFTOVER. ANYONE ELSE FEEL THIS WAY? HOW BAD ARE THE SAND THRUS? IF YOU JUST KISSED THE WEAVE IN A FEW SPOTS ID SUGGEST A FEW WIPES OF BEHR LOW LUSTRE CONCRETE AND TILE SEALER.
Basically what the OP is after is a sanded gloss. Its what I do on every HP short board. Its just a second hotcoat sanded. I follow that with a couple of coats of sealer.
Gloss resin has a lower viscosity than lam/sanding resin. It costs a lot more, too.
If you don’t want that super shiny finish, don’t spend the extra money. Just use lam resin and add a little extra SA. Warming it will help a little, but adding solvent (styrene) will do more.
What’s commonly called a “Piss Coat” is made by adding Surface Agent, a small amount of Styrene and about 10% Acetone to Poly Lam Resin. Should be used over poorly sanded(i.e. Over sanded) hot coats. In your case just touch up the oversanded spots with sanding resin and sand by hand. Once you get to the point where you can brush a good even hot coat your burn thrus will go away. If you use a piss coat over the entire board; sand it by hand with 180 or 220
.02 from a back yarder.
Why do a second hot coat or gloss at all? If your burn throughs aren’t that bad, you don’t care about super shiny, why add more resin? Sand it to 320 or 400 then a few minutes with a wool bonnet and some cutting compound.
The key is a tight flat lam and maybe a little baste at laps & box patches, then hot coat then sand it then a quick polish
Probably want to add something to seal the burn throughs so they dont suck water. Resin or speed finish spray coat. You can use Upol #1 to spray the burn throughs. A few coats of Upol #1, lightly sanding inbetween each coat, will seal your burn throughs and wont add much weight if you dont want to add more resin to the board. But a thin coat of sanding resin cut with styrene 5%, wont add too much weight and will totally seal any burn throughs. If that coat goes on smooth, you can start sanding with 320 then wet 400!