So i just glassed on my keel fins. I used Poly resin. Before glassing onto the board I lammed each side of the fin with 1 layer of 6oz glass and added a roving halo around the perimeter of the fin. I put saturated Roving along the base of fin and 2 full patches of 6oz that covered the entire fin and lapped onto the bottom of the lammed board extending 4-5 inches out from the base of the fin. I then put oval patches that went about 2 inches up the fin and 2 inches onto the bottom of the board for reinforcement. Will this be enough glass or are the fins likely to be weak and break. I thought 2 full patches + the oval reinforcement patches would be enough but I have since read a bunch on sways and have been getting mixed messages about glass on fins. whats your opinion?
That’s what I do without any problems. Only, I put the football patches on before the full patches only because it made it easier to blend and fare back to smooth when sanding. Mike
Hey rooster, sounds good. I put the footbal patches on last because on the few boards that I have made, I tend to get sands through near the base of the fin when sanding near the Fillet. Figured it would be better to possibly sand into the football patch a little bit and not the full patches that provide most of the structural support. I should just work on being a little more careful when sanding lol. Thanks for the affirmation man!
…all depends on the fin area and height. You say keel fins, so about 9 inches length, and low aspect fin, so you would be ok.
I assume that are wooden fins or plywood fins, if not I do not get it why to put fiberglass before…
Thanks Barry. I will give that A try. That board is sooo sick man. I drilled a hole through each of my keel fins and filled it with tinted resin. Has a similar affect to the twinnies on your board. Thanks again!
Would you mind posting some pics? I’m very interested in your fins.
BTW, I glassed on my fins as follows: foil fins, put on one layer of 6 oz glass, glass fins on with 2 layers of 6 oz glass (in a 45 degree angle). I didn’t use any rovings. Been going strong since september now.
There were my first ones though, so I don’t really have a comparison. But they work fine and look ok, so I’ll use this method again with my next boards.
Hey, yea I will post some pics soon. The fins are hotcoated but I have not sanded them yet so they still look a little rough. The method you used, the bias cut cloth at 45 degrees sounds like the method outlined by Bill Thrailkill. I am probably going to give that a try on my next board.
I can’t argue with success on the part of my fellow Swaylockians. I have had different experiences however…
I’ve worked on plenty of used boards with glass-on fins, many of which were showing telltale signs of weakness in the form of cracks, repairs, replacements, or even missing fins.
I have had fins that were glassed-on more substantially than the ones shown below bust loose on bottom turns.
Having learned lots of things the hard way, I have long since laid cloth on heavy… and with only a small amount of fin rope. The 45 degree weave application makes a lot of sense and is what I do. I do lay-up a few strands of rope, a few pieces of cloth all the way up the fin and out on to the bottom of the board and 10 or more layers (cut narrow) so they fill in at the fin base are laid over that. I have used as many as 20 layers with good results. Some of that obviously gets sanded away but the end result is that the fill along the bases is pretty beefy.
Even glassed heavy, I offer no guarantees. I had a friend bring back a board I had made him. He somehow managed to back his truck over the board and… broke all 3 fins off(!)
