Surfboard Fins for Thruster

thingiverse

Glass on fins for a surfboard. Total hack amateur fins, no high-level thought went into the design. I just wanted to make my own. The tab is on there just for glassing. The other design was going to be a Future Systems compatible design but I decided to just glass on the fins rather than try to put in the fin systems. The fins I've been using are about 6.5mm in thickness, This print is 4.5mm and needs to be 5.5 to get the correct thickness. Just scaling up for now but will upload a better design as I get one. The picture compares my Future Systems fin to a fin I printed and glassed. See the instructions for what I did to finish this off. This first fin is a little small/thin. It has too much flex, and I think the thicker part needs to be closer to the front to produce a good foil. Will keep posting as I refine the design. Instructions Scale the fin to your preference. Might want to scale the thickness depending on how much glass you are using. I used Sun Cure UV epoxy and 4oz glass. Saw a video on Youtube on how to do this with wood fins and Solarez. It looked much quicker than traditional epoxy. See it here: https://www.youtube.com/watch?v=d24hTqjCSYY Mount fin to a stick/handle so you can move it in and out of the sun. Apply two sheets of fiberglass to one side. Brush on epoxy, get out all the bubbles you can. Expose to Sun/UV. Trim excess cloth with razor blade when gelled but not hard. Do other side the same way (1-4). Repeat as necessary if you want more glass/thicker fins. Sand down the rough edges/bumps until satisfied. Brush down both sides with a final coat of epoxy and let it harden in the sun.