I realized that in my fever for the other projects, that I had never actually seen The Last Jedi, so I remedied that.
At timecode 2:22:22 (what a cool coincidence...) in the movie we see it split down the middle with the crystal exposed.
This got me thinking. In the capture, the crystal appears to sit just about even with the end of where the retaining ring goes. If I cheat a little by sliding the retaining ring up, I can then fit 4 18650's and my oversized speaker, fully behind that in the lower handle. That gives me 14.8v-16.8v for driving the blade directly and enough Ah to run it for a good long time.
A little PWM will manage regular (full) brightness, with the ability to surge to 130% brightness for simulating strikes. Sounds like a plan.
This is also the best spot for them weight wise as it will balance out the blade much better than having them further up top. I think I might extend the lower tube so the joint is back in the middle, but measurement wise, those were the 'correct' dimensions. I just don't want to sacrifice the crystal chamber, or battery life, so this seems like the next best compromise.
So far I've only generated the replica buttons and the blade tip for the 3D printed parts, but they turned out nice...
Somewhere along the line I also generated screen accurate grips and I have the sliced gcode from it, but I don't seem to have the STL's or the OpenSCAD source code for that anymore. :(
Snaps together, retains the moving button between the two parts, is printable flat, and is accurate enough.
The bottom sticks out a bit when pressed so I can use it to trigger a microswitch in the body parts later.
The tip is a press fit for the polycarbonate tubing I have for the blade, and has a hole to allow air to move through if I end up needing that. I have 4m of LED strips in my blade, so I might.
Took the time to add a photo of the mostly completed body.
It was made from 2 sink extension tubes, some square stock, a drywall mud tray, and a few 3D printed bits. Total parts cost so far ~$20.
The only batteries I have suitable to power the 12v blade are 18650's but using those without a DC-DC boost converter doesn't leave a whole lot of space for the crystal chamber.