3D Printed Surfboard With Blinkenlights

As I love (river)surfing I have done a few surf related projects over the last years like my LED fins or the electroluminescent surfboard. It was only a matter of time when I would start to make a fully 3D printed surfboard. Naturally, as with most of my projects some lighting effects were mandatory.

There are a few DIY 3D printed surfboards as well as a couple of commercial surfboard companies that use 3D printing and I have listed some below. The design for my board was mainly inspired by Wyve.

DIY

• Surfboard 6'4 by KILIANR2000
• 3D printed surfboard by shizzlefish
• 3D printed surfboard by Henry Mayne
• 3D printed surfboard by Jody Roth

Brands

• Paradoxal surfboards
• Wyve surfboards
• Swellcycle surfboards

• 3kg of transparent PETG filament
• fin boxes
• leash plug
• venting valve
• epoxy resin
• 2oz s-glass
• 4oz s-glass
• SP621E bluetooth LED controller
• side emitting WS2812B LED strip, 2m
• IP-5305 5V boost converter + Li-ion charger
• IP68-rated USB-C sockets
• IP68-rated non-latching push button
• 14500 Li-ion battery

The shape of the board was designed with the freeware software BoardCAD. I modified the shortboard template so that the dimensions fit that of a typical riverboard: 5'3 x 19.5" x 2 3/8"

To further modify the design I used Fusion360. Unfortunately, importing the design as a step from BoardCAD into Fusion360 did not work so I had to use stl format instead.

First, the hexagonal pattern was extruded from the solid blank. I also added elliptical holes to all sidewalls. This reduces the weigth but also ensures that air can circulate to the centing valve to prevent delamination of the board.

Then, I added the finboxes and holes for the leash plug and venting valve.

Next, I added space for the all the electronics. The LED strip was integrated into the bottom of the stringer and some of the hexagonal walls. The battery, switch and charging electronics were integrated into the rail near the tail. Finally, the board was sliced into 17 pieces that would fit on my printer and I added keys and slots to the matching pieces to ease the assembly.

I decided to use PETG filament instead of PLA which makes the board slightly heavier but also more sturdy. For better visibility of the LEDs I used transparent filament.

At first, I wanted to print the pieces vertically in order to reduce the amount of support material. However, this resulted in many spectacularly failed prints like shown in the picture above.

This was definitely the most extensive 3D printing project I ever did. It took 175h of total printing time and 2.6kg of PETG filament (not counting the failed and test prints).

After printing and removing the support material I slightly sanded all the pieces. They were then glued together using 5-minutes epoxy. The keys and slots that were essential for the alignment of the pieces and helped a lot to provide stable joints. Clamps also come in handy when assembling the pieces.

Starting at the tail I first assembled the left and right pieces and then moved on to the next section.

In hinsight, this should have been done after laminating the board as it would have avoided some problems.

After placing the finboxes inside the cutout, I filled it up with epoxy resin (same as used for lamination) using a syringe. In the venting valve you first need to drill a hole at the bottom, it was then attached with epoxy resin. The venting valve is permeable for air but not for water it lets air escape when the board heats up and prevents delamination. Finally, the leash plug was also attached with epoxy resin.

Next I added the LED strip to the slot at the bottom of the 3D print (with the LEDs facing upwards) and fixed it in few places with hot glue. The the battery, LED controller, charger IC, USB-C socket and push button were soldered together and added inside the rail. In hinsight, it would have been better to add the push button after laminating the board as it protrudes from the top and makes the laminating process more difficult.

At first the board was lightly sanded then all parts that need to be protected from epoxy resin, like the USB socket push button, fin boxes, leash plug and venting valve were covered with masking tape. Another layer of masking tape is placed along the center of the rail which wer laminated using the cut-lap technique.

There are various tutorials that explain how to laminate a surfboard. We mostly followed the instructions by sheldrake for the lamination of cardboard surfboards. Since the blank is not solid epoxy resin cannot simply be poured over the fiberglass cloth because it would drip through to the other side. Instead the epoxy resin for the first layers is carefully applied with a brush.

The lamination was carried out in the following way

1. simultaneous lamination with 2x 4oz S-glass using brushing technique on top
2. lamination with 4oz S-glass using brushing technique on bottom
3. 2nd lamination with 6oz E-glass on top
4. 2nd lamination with 6oz E-glass on bottom
5. hot coat on top
6. hot coat on bottom
7. sanding
8. gloss coat on top
9. gloss coat on bottom

After each lamination the excess fiber glass cloth is cut along the tape line at the rails. Also any irregularites like cutlap lines or pieces of fabric were sanded off, so the next layer of fiberglass or resin will go over a fairly smooth surface.

As mentioned before there are several things that went wrong and that I would do differently in the future.

1. The push-button was damaged during sanding and had to be replaced in a delicate procedure afterwards. It would have been better to add the button after lamination
2. Some epoxy resin went into the hole at the bottom of the venting valve so it is also advisable to add it after lamination
3. Epoxy resin also got into the USB-C socket so it should also be added afterwards although this was not really possible due to the shape of the socket that I ordered
4. There are some puddles of epoxy resin under the fiberglass cloth, especially where the fabric touches the blank. I guess this is due to using too much epoxy resin and not carefully spreading it

I tried out the board at the Eisbach riverwave in Munich during a cold winter night.

It was a fun session but it didn't go all that smoothly. First, with 3.3kg the board is rather heavy compared to traditional river boards. Secondly, I should have put more effort in optimizing the shape as the board reacts a bit sluggishly on the water. The worst thing is that some water got into the board and I later noticed that there was not enough lamination around the USB-C socket. Drying the board took ages and the water unfortunately damaged the battery so currently it is still under repair.