Backlit Cube – Pitch Black Solve

Below is a video of a 35-second solve in total darkness. No, not a blind solve. I can’t do that!?! A solve on an LED-backlit cube….

(music: Medeski Martin & Wood, “Uninvisible”)


The cube is a Ghosthand Crystal Cube that I hacked/modified nearly a year ago. My last blog post on the cube details the modification and shows a casual 55-second solve.

The OEM cube has a round core with small button cell batteries, two LEDs, a motion-sensing switch, and a small IC. Movement caused the lights to blink at an annoying seizure-inducing rate. The random flashing also made it hard to solve in the dark — and that’s the whole reason for backlighting it, right!?! So, I wired around the IC (meaning constantly-on, without blinking) and then added a micro-switch to turn it on/off. The switch sits in recess in the core and is accessible with a paperclip after removing a top-layer corner. I’ve thought quite a bit about other ways to switch it; none seem viable without a substantially more complicated modification.

Nearly impossible to adjust tensions, it’s not a cube that lends itself to speedsolving.


At 35 seconds, the solve is slightly above my 28-30-second average. The cross was easy and the F2L was not too bad. I had to two-look the OLL, since I don’t know the knight move cases. Then came a G perm that took me a couple seconds to recognize. (Recognition is a bit slow on this cube.)

Whenever I get an on-camera solve, I like to use it as opportunity to dissect my technique. So, I did a reconstruction of the solve and spent a couple minutes figuring out a much more optimal solve. Both are below, with all sorts of support — a move-by-move breakdown, manipulable animations, and a video modeling both.

SCRAMBLE: F' L F' R2 B2 L' D B R' B R2 L2 U' B2 L R U' R F R D2 L U' B' U2

video: my solve vs. a (more) optimal solve

MY SOLVEanimation
D’ R’ L y U’ R2 D’ y’ y’ // CROSS
U2′ R U R’ U R U’ R’    // F2L-1
y’ y’ R U R’ U’ R U R’ U’ R U R’ // F2L-2
y U’ d2 U’ R U’ R’ y2 R U’ R’ // F2L-3
y d’ U’ U’ R U’ R’ U U R U’ R’ // F2L-4
F R U R’ U’ F’ // OLL-A (16)
R2 D R’ U2 R D’ R’ U2 R’ // // OLL-B (23)
y y y // TIME WASTE
R U R’ y’ R2 u’ R U’ R’ U R’ u R2 // PLL (Gd)

D’ R’ L D’ R2 // CROSS
U R’ U’ R L U’ L’ // F2L-1
R’ U’ R // F2L-2
L’U L U R U R’ // F2L-3
y’ U R U R’ U2 R U’ R’ // F2L-4
F R U R’ U’ F’ // OLL (45)
U R U2 R D R’ U R D’ R’ U’ R’ U R U R’ U // PLL (Ra)

The side-by-side between these two versions is pretty staggering. First, the cross would have been much easier if I had placed orange with just D’ R2 instead of a y U’ R2 D’. I should have caught that during inspection. Second, my emphasis on front-right inserts for F2L means missed much easier pairs and wasted cube rotations and U moves. Lately, I’ve tried to focus on look-ahead (without much success). I think that time would be better spent first getting comfortable with insertions in the other slots. Untimed, I’m much better with them. But, with the clock ticking, I tend to solve F/R only.

Anyway, a fun project spurred by a fun cube….


6 thoughts on “Backlit Cube – Pitch Black Solve

  1. February 8, 2014 / 10:12 pm

    Hello would you mind sharing which blog platform you’re working with?

    I’m planning to start my own blog in the near future but I’m having a difficult time choosing
    between BlogEngine/Wordpress/B2evolution and Drupal. The reason I ask is
    because your layout seems different then most blogs and I’m looking for something unique.
    P.S Sorry for being off-topic but I had to ask!

    • Adventures in Cubing February 9, 2014 / 12:05 am

      I use WordPress with a highly customized template. WordPress is powerful and accessible at the same time.

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