Repurposed Aluminium Longboard

Back from Boston, at home for the summer, I decided to make a long board of my own.

It had to be special, rather than just store bought. I had spotted in the atelier some leftover extruded aluminium profiles from an old dismounted sun awning and started tweeking with some ideas about the structure of my board.

Those profiles inspired me to design a skeletal light frame design, with the ultimate challenge to build a metal longboard lighter than the traditional epoxy-wood assembly.

I started by scanning and drafting in AutoCad the available profiles.

After drafting in 2D, I started to refine the assembly with a 3D model in 3D Max.

The rectangular bars span from truck to truck and constitute the spine of the board. The 1/4 rounded profiles, the ribs, overhang on each side and provide foot rest and facilitate manoeuvrability. All bars are interlinked with 3D printed connectors, tightened and pressed with 3mm stainless steel rods.

First action, clean the aluminium bars, then cut them to length..

A paint stripper is applied to the profiles to remove the thermo-paint. They are thoroughly rinsed, dried, and for a "raw techno" look, they will be sanded smooth with 320grit emery cloth after machining... Then I start the cut outs on the manual copy router I'm fortunate to have access to.

These ribs are definitely trickier to produce. The cut outs are highly 3-dimensional and the ends are contoured in a streamlined fashion.

For the hardware, I used my dad's 3D printer. It's a Prusa RepRap kit ordered online, assembled and customized to extend the printing capacity to 20x30x45cm, and equipped with an electronic mounting board for raft adhesion.

For the software, I used Cura 15.04.03. Simple and efficient. Connectors were designed in 3D Max, transferred into Cura and printed with black PLA filament, with the following settings:

• layer thickness; 0.3 mm
• printing speed: 50 mm/s
• melting temperature: 240°C.

The twin profiles of the Spine are linked by the end mounting soles for the Paris V2 trucks and form a 90 cm long triangulated truss. The 3D printed connectors are matching the contoured flanks of the aluminium profile. The are hollowed out and are kept in compression with 3mm stainless threaded rods, washers and bolts. Together, they form a long and lightweight aluminium beam, easily capable of supporting a 80lb+ rider...

The board is put through a structural dry fit test with tension belts, before drilling Spine and Ribs for final assembly.

Time to put the beast together... Patience finally pays off and everything fits in...

Flexible bumper pieces are modeled and 3D printed (with TPU rubber filament) to cap both ends of the board and complete the design.

Moment of truth: 2604 gr on the scale, lighter than any regular wood-epoxy board ! Challenge met !...

For finishing touches, adhesive anti-slip stair grip tape (from Abcosport) is applied along the aluminium profiles, glow in the dark tape placed in the groves and Paris V2 trucks installed equipped with multicolored LED light up wheels... Psychedelic !