Challenge: Make these cylinders as portable as possible: long-life rechargable battery, no wires. So how much room on the ends of a tube is that going to require? The previous page has images of the tube in various states which are nicer to look at ;-)

"The End" Prep of headers for the LED groups in the tube - important for keeping track of the individual LEDs, in proper sequence.

Can the components really fit in this tight space? Plan first!

Board prototype ready to accept the LED headers.

Nasty wirewrap scheme (for testing). The four cutouts were for the temporary 'legs.'

Temp insulation before cramming all these bare connections into the tube.

Prototypes of temporary support legs.

Wood is easy to fuss with when trying different sizes. But a horrible idea because of the huge amount of space they occupy.

Darn crowded!

A header hits edge of the tube, others are too tall. That’s why you make a prototype.

Longer legs provide more room. Also trying a location for IR sensor.

Theoretical fit for the board.

Using a 4-inch mailing tube to proto the cap size. Partially fit.

Oops! Tops of legs are too thick. Cap should slide up level with IR phototransistors.

Meanwhile, at the other end, the power circuit and voltage booster board (a "MintyBoost" from adafruit.com).

Again a nasty soldering hack, but gotta try it this way before committing to a custom board.

Power board in place. With a new button for side access, next to the charger plug. Hopefully the power booster and battery will have room.

Very tight squeeze, not good for a soft LiPo.

Uh huh, that’s not gonna work.

How the end cap might fit...

...but this definitely needs more height for the battery.