Got a single fin board I made last year and feel like practicing glass ons. My question is, can I get away without using roving/glass rope for small sidebite fins?
Sure, if the fins are small - like under 3". But you’ll have less trouble with bubbles if you use small strands of roving or a subsistute like pulled strands from scrap cloth.
As Mike said, it is hard to get the glass to turn a hard right angle at the fin board intersection so the roving helps soften the angle. Otherwise the glass will lift and air will get in between.
I have successfully used a method that Bill Thrailkill taught me. The key is to cut out your patches with alternating angles of the weave: 90 degrees, then 45 degrees, etc… Make a few short patches for the fillet area and apply them just before your last full patch. BTW - I have always used epoxy. The drawback to epoxy is that you will never achieve perfect clarity. On the plus side you won’t stink up your neighborhood, which is why I use it. I am able to reduce the number of bubbles considerabley by applying some plastic to each side. I like gallon sized ziplock bags that have been cut in half. After you stick the ziplocks to the fins then you can run a plastic spreader or you finger over the fillet area until it is a nice right angle. Leave the plastic on the fin until it gels, but not completely hard. If you time it right then you can use an exacto knife to cut away the excess material.
Very clever. I will remember that. Thx
I have NOT used roving, to mount a glass on fin, since 1960. Multi layers of bias cut glass is easy to get into the sharp 90 degree, fin/board junction. And bias cut cloth is considerably stronger than the common application of cloth in the 180/90 strand direction. In the pre leash era, it was common for a board to wash in to the beach and crack, or break off the fin. After I abandoned the use of roving, I NEVER had a cracked or broken fin, as a result of a board lost to the beach. If it worked for large reverse D fins, it will surely work for the small side fins you make reference to.
Mix up some cabosil or microfibers with resin. Put a bead down each side of the fin and run your finger over it to make it smooth. let it dry and glass fin on. I have done this with every kind of fin and it works great. You do lose the clarity though.