Behind the scenes I’ve been working on a Stand Up Paddle (SUP) fin project for quite a while now, 3D printing many prototypes, and more often than not, failing! There is more to this project than meets the eye, but for now the details are under wraps. However I thought it might be interesting to share some of the 3D prints in case anyone feels inspired to give it a go themselves.
The design pictured above is the first one that worked successfully without breaking or having other technical issues. Printed in 4 pieces on my Cocoon Create due to the size, it required a bit of gluing, and as you can see from the pink highlight, a bit of gap filling with a 3Doodler Pen (if you want to know more about using a 3D printing pen as a gap filler, check out one of my previous posts all about it). As a result the fin is about 400mm long, huge compared to the fin that came with the board (which for any SUP fans out there is a Slingshot G-Whiz 9’4″)
These images show some of the breakages I’ve had due to layer delamination – unfortunately the optimal way to print the 4 pieces in terms of minimising support material and warping is vertical, however the optimal orientation for strength is laying down on the flat sides (similar to the image on the right). A bit of an oversight on my part I’ll admit, however I was genuinely surprised how much force the flat water put on the fin. Another issue may be the minimal infill, which was also beefed up in my later prints to add internal strength. There is always a delicate balance between print orientation, layer strength and infill in 3D printing, to name just a few!
The main thing is that the fin prototype now works, and I may have a more advanced version being printed using Selective Laser Sintering (SLS) as I write this… If you keep an eye on my blog by subscribing below, you may just get to see where this project is going 🙂
– Posted by James Novak