So I’ll probably be making another fish here soon (almost exactly like the one I just made) for a friend, but have a question regarding the final sanding of fins…The wooden ones I made for my board were really smooth after I glassed and sanded them OFF the board. Now after they were laminated onto the board and I hotcoated the bottom of the board, I also layed hotcoat over both fins and since they are vertical, they looked real “drippy” after the hotcoat had gelled. I sanded them down as much as I could, and then the same thing happened when I applied a gloss coat over them (Not even sure if you’re SUPPOSED to lay a gloss over the fins)…So do you just take 100 to the hotcoated fins and get them down as smooth as you can and leave it at that? Any suggestions or lashings are welcome. Thanks. I’m just making the second fish because he wants one and will pay for all materials, I’m not trying to make any money off this…
what did you use to put hotcoat on the fins? brush? Sorry if that question seems stupid, but you never know… also, are you using epoxy or poly? How hot was the hot coat?
sorry to seem nosey but it would help a bunch.
Yeah, sorry about that! I used the same brushes I use for hotcoating, which are 3" disposables…Hotcoat was mixed with 1% catalyst. Poly resin. It just looks like (if you’re looking at a fin from the side) acros the entire fin, you can see resin “falling” down to the base at different heights, like RIGHT when it started to gel. You can’t see the drips here really, but you can see the “bumpiness” of the fin…
Howzit tenover, The way to eliminate those drips is to bush the fins first before the bottom This way by the time you get to the areas around the fins the resin should have drained off the vertical sides and will be smoothed out while finishing the bottom brushing. Use same technique for glossing. Aloha, Kokua
Makes sense kokua, thanks.
The fins are the only places on a surfboard that I try to put the hotcoat or gloss on as thin as possible. Just like Kokua says do them first and let them drip off. If you continue to get the runny drips you can hot coat the top & bottom but not the fins, put the board in the saddle and hot coat the fins on one side, flip and do the other side. Or you can spray them lightly with UPOL after you sand the bumpy hotcoat down for a shine.
-Jay
Hey tenover , you can also use a little less catalyst to slow the things down to insure the drips drain off. Aloha, Kokua
I always do glass-ons with the board standing on a rail as Resinhead suggests. You then can do the outside of the upper fin(s) and the inside of the lower at the same time. Get a small level on the top fin and make sure everything is even when you set it in the rack, shim it with small towels. I run tape (sticky side up) around the upper fin and tape a piece of paper to the bottom of it. Just use tape only on the lower fin. Thin the resin more to reduce brush marks. I sand them standing like this but use a padded bungee cord to hold the board in.
So you put the board in the racks sideways and hotcoat one side of the fins, let cure, do the other side, let cure, then do the bottom of the board??
I’d follow Kokua’s advice.
I’ve glassed over 40 glass on boards, and never once, have I used a separate coat of resin just for the fins. I just finish brushing the fin really well, then go onto the surface of the board. 38 times, it came out clean.
Nobody’s perfect.
Yes, I stand it up sideways and then do the bottom. Most of time I’m doing it this way for repairs to glass-ons, particularly on restorations where they want the original fin(s). If it’s just a glosscoat on new fins on a new board, I generally use the method Kokua explained. You don’t need a lot of gloss resin on new ones, so I really thin it down. The Silmar gloss I use kicks so slow anyhow I don’t have to use less catalyst. I also mask the base of the fin (in the middle of the fillet) with tape and paper to catch the drips. When I do the bottom I just mask with tape only slightly above the previous tape line. If the new fins you buy are rough, tape off the base about 1/2" and finish them to your liking off the board so that you only need a gloss above the fillet when installed.