I think I’ve redesigned the prototype about 12 times in the last 3 weeks. I’m finally happy with the plan though, and hopefully throwing the rest of the wheel together to get video this weekend. The biggest change I’m happy about now is the LED mounting. I had tried a variety of materials and adhesives for mounting the LEDS in alignment with the holes. Here were some of the experiments in LED mounting:
a) LED strips epoxied directly to the aluminum – looks great but leaves the LEDs not serviceable; no telling how well the epoxy will hold up over time with assembly, disassembly, flexion during use, temperature changes; does not protect the LEDs from a misaligned insert scraping at them.
b) LEDs pressed into place with a foam backer – works, but really time consuming to align everything properly, and leaves the ends around the inserts unprotected, so not that good.
c) Polycarbonate mounting strips cut on the CNC to match the curvature and LED spacing inside the tubes – works great for one row of LEDs, but takes too much space away from batteries, inserts, wiring inside the tube if 2 rows of LEDs are used.
d) LEDs superglued to 1″ polypropylene tubing aligned with the holes, the polypro tubing cut lengthwise into strips just big enough to mount the LEDs – this works great in almost all aspects. Still a bit hard to align two LED strips perfectly parallel on the same strip of polypro so that the LEDs mesh with the holes perfectly on the first or second or fifth try. Also it’s still a tiny bit too tight for the batteries. This is good enough for the prototype though. All sold wheels will use the next method though.
e) THE BEST — LEDs laminated together with layers of thin clear plastic and epoxy resin to create a monolithic rigid LED insert. These will be molded over a form specific to one size of cyr wheel. This method ensures proper LED alignment to the holes on the first try, and then each time the strip is inserted or removed afterward. Each LED strip for a particular size wheel will also be interchangeable. This makes a strong, thin, repeatable part.
As I get further into the details of the build, I’m realizing these are going to cost more than originally announced. The full price for a Rev1 LED wheel will be $3500, rather than the original $2700. Beta testing versions will still be available starting at $2300, but the price will increase by $100/month until December 2016 when Rev1 wheels are in full production. For the Kickstarter campaign, beta pre-orders will also be $2300, but won’t start shipping until March. A limited number of Rev1 wheels will also be available on the Kickstarter at $2700. I’m still going to take a handful of direct beta pre-orders that will ship before the kickstarter wheels. This all gets a little confusing, so I’ll probably put together a timeline to straighten it all out.
Also, beta testing is getting extended to about a year. I’ve been hearing concerns about the holes weakening the tubing. I’m confident in the strength of the design, but a lot could still be gained from a longer testing period. Full Rev1 wheels will not begin shipping until Fall 2016, but a lot more test wheels can be produced in the interim. Beta users will have the option of a discounted upgrade to a Rev1 wheel after beta testing is complete.
There are a lot of pieces to balance, but I’m working on a plan that gets more wheels out for real world use and feedback, incentivizes early adopters, protects the buyer’s investment, and brings in some income as I’m developing and fine tuning manufacturing. I’m hoping to have this sorted and posted tomorrow.