On the morning of the first Christmas holiday, the 25th of December, an impulse hit me around 9 o’clock. I wanted to go skiing again. No problem in itself, since gear and ski resort were quickly sorted, and routes, slopes, and weather all lined up nicely for the next day.
It would have been nicer, though, to bring my new 360-degree camera along and finally test it. Except when I bought it I had of course forgotten to order a matching helmet mount straight away, and over the holidays not even Amazon could get a mount to me in time for the next morning.
Setting off without the camera would have been a shame, but no great loss. Then again, dinner at my parents’ place was not until 7 in the evening, and I had nothing else planned for the rest of the day. That left roughly ten hours to think up a solution and kill some time along the way. And what do you keep a 3D scanner, a 3D printer, and a few years of experience with 3D modelling around for, if not for exactly these moments?
The idea was quickly settled. I would simply build the mount myself. The only open question was what, besides the helmet and the camera, I could scan in to give the whole thing that certain something. The answer was sitting in the fruit bowl, where a banana was slowly ripening that had seen better days.
The plan was set. A banana-shaped camera mount.
The Day
10:12
In my head the idea is fully worked out. The internet takes some of the load off me, because a finished model of the camera turned up, which saves me a full scan. That leaves the helmet and the banana.
10:56
The helmet behaves as expected. Big and textured enough, the scanner takes it without complaint. Easy peasy, I think to myself, this project will be done sooner than expected.
11:34
The banana sees things differently. It too has to be scannable from every side, so I try chopsticks as a holder. It keeps slipping off, and with every new setup the banana grows more unstable.
12:14
Eventually the banana gives in too and is fully scanned. From here it gets more pleasant, since everything else happens on the computer. Rough scaling, squashing, stretching, building the contact surface between helmet and banana.
13:42
By now the negative of the camera sits inside the banana as well, so both contact surfaces are done. That brings me to the actually interesting part, the locking mechanism.
14:14
The screw connections deliberately do not run parallel, but at a slight angle to one another. That way I get a geometric fixation on top of the clamping, and should the screws ever work loose without falling out entirely, the camera still stays put. In theory at least, since that is hard to check on screen.
16:43
The lower shell goes into the printer as a prototype first. To save time I print with rudimentary settings, two wall lines and 10 percent infill, since the only question is whether the part is printable at all and whether it fits.
18:37
Both can be answered with yes. That leaves just enough time to start the real print with six wall lines and 30 percent infill before heading to my parents’.
23:52
Back from dinner, a finished part is waiting on the print bed, and this one fits too. All that is missing is double-sided foam tape, so the banana sits on the helmet in a way that lets it come off again in a crash. Done for the day.
Next morning, 9 o’clock
All finished, off we go.
On the Slope
That the mount draws attention became clear at the very first lift. Over the course of the day I was approached and talked to several times, only the phrase that came up strikingly often was “fish fin”, usually paired with the question of whether the thing brought any aerodynamic benefit. So I still need to work on the paint job.
Apart from it not being recognised as a banana, the ski day was a full success. The construction sat rock-solid on the helmet and the footage came out excellent throughout. The only thing I missed in the end was the option to record the current speed at the same time. The app can do it, but syncing the speed data with the footage afterwards is quite a bit of effort. So the next project is basically already decided.
With the good feeling of having designed, printed, and actually used a prototype within 24 hours, I drove home content that evening.