i have a board with 2 glass ons that are cracked at the base (center and side fin)
when you wiggle them the glass on the board lifts off the board so it seems to me its delamed all around the base of the fins.
i was going to dremel the fins off at the base because if seems like the easiest way to remove the fins. then proceed to strip all the previous glass off the fins and re-glass them.
how should i solve the problem with the loose glass all around the fin base? cut out a section and lay new glass? it seems if i did that it would still be solid to begin with but may weaken eventually since the patch is not part of original glass? any ideas?
You’ll have to repair the loose glass, that’s no longer adhered to the underlying foam. If you don’t, there will be solid base for the fins be adhered to, and they’ll likely wobble.
Two ways. One: dremel off the fins as you plan, then mix a batch of lam and work it under the loosened glass by flexing it and working out the bubbles. Two: grind off the loose stuff and lam a new base using a couple layers of scrap glass, prior to re-setting the fins on the board.
Howzit Honolulu, I find that most of the time there’s also some damage to the foam under the broken fin area. cut the delammed glass off and check the foam for cracks. I use Q-cel to fix the cracks then reglass the area then glass the fin back on the board. If you don’t repair the damaged foam it’s like building a house on an eartquake fault and you won’t have maximum strength. Aloha,Kokua
i figured i may have to cut a section out on the bottom. is there a certain shape i should cut out of the deck (say a wide diamond shape or something of the kind) to maintain strength at the base of the fins?
i’m thinking if the cutout was similar to the outline of the base of the fin the deck patch will be weak.
Kokua’s right. Almost all of the loose glass-ons I’ve repaired have the foam split horizontally. It’s very difficult to see, so you have to remove the glass in the delaminated area and look carefully. If it’s split, you have to get some lam resin deep in the crack and clamp the area down until cured. Fill the areas that you removed the glass from with a cabosil/Q-cell sanding resin mix, and sand it level. 6 oz. cloth over it going at least 2" onto good glass, hotcoat, sand. Clean up the fins and glass them back on (see archives). You can apply a fin patch over the entire tail area if you want. Glass it to 1/2" of the rails and cut the front into either a half-diamond or rounded shape.