Critical Cane - d20 walking stick

For that extra bit of style, for the gentleman, lady or otherwise fine folk of extravaganza. A lit up d20 crowns this cane.

All you need:

• 1 55mm d20 (Koplow)
• 3 d20 holders
• 1 shaft head
• 1 shaft battery
• 1 shaft bottom
• 1 foot
• 12 M3x10mm countersink head (T10)
• 3 3x16mm countersink head wood screws (T10)
• 9 SMD 1206 2.9V LEDs (anything that small and around 3V will work)
• 1 2xAA battery holder (check pictures for reference)
• 1 sliding switch (check pictures for reference)
• soft wires, I used silicone sleeved wires
• heat shrink tubing
• 25mm wood dowel
• optional: 12 heat sink threaded inserts M3

Printing:

• 3 perimeter
• 100% infill
• PETG, ASA or ABS (definitely something tough)
• all parts are already in print orientation

There are two versions of the head and bottom piece. The thread cut version comes with 2.5mm holes, so you can directly screw the bolts into the printed part. The thread insert version has 4mm holes and a little recess for heat sink threaded inserts. The threaded inserts make assembly and disassembly a lot easier, especially when it comes to swapping the batteries.

Soldering:

This comes a bit tricky on the small LEDs but otherwise the circuit is simple as the LEDs run with 2.9V and can directly be hooked up on the battery. Check the pictures for reference. Each d20 holder can take 3 LEDs, solder them in parallel and leave some extra wire, total length 120mm. On the backside of the LEDs is a green bar, the wide side is the positive end and I used the red wire fore that to stay consistent. I recommend presolder the contacts and wires and use tweezers to help guide the wire. I also used a small vise to hold the LEDs. The distance of the LEDs is 18mm.

Next insert the LED strip into the holder and fix it with some glue or epoxy. I used some epoxy as I have this on hand, simple CA glue will do as well, its just to prevent the LEDs from moving.

Also always check if your LEDs work before you apply glue.

With the holders done, you mount them on the shaft head, there is a cutout for the wires, make sure not the clamp and damage them. After that you can feed the wires through the shaft head, red is running through the side where the switch gets installed, the other is running to the other end. Now you know the exact length needed. Make sure to leave some extra, but not too much, so you're able to remove one holder to fit the d20 in.

Solder the three wires of each polarity together. The one going to the switch is soldered to one socket on the switch and the other is soldered to the battery holder. Finally solder the other battery wire to the switch. 

The switch can then be pressed into its hole and secured with screws or a bit of glue. Check the pictures for reference and also use some heat shrink tubing.

To protect the battery holder cable at the bottom, I added a bit of hot melt glue. 

Assembly:

With all the soldering done, you notice that those parts are now connected and can't be undone, without desoldering. First connect the shaft bottom and battery parts with 3 screws. Next you insert the battery holder into the shaft. Then you can place the shaft head, but be careful not to damage any wires, I recommend winding them up a bit (see pictures). Screw everything together, be careful on the cut thread parts, not to over tighten the screws and ruin the threads.

Check if all the LEDs still work, otherwise disassemble and check if you might have damaged something or a soldering broke or the like and repair it.

Next up, detach one of the d20 holders and insert the 55mm d20. Make sure your favorite number is up and attach the d20 holder. Now the top part of your cane is done and you add the wood dowel. 

Before adding the dowel, check how high you want your cane to be. Take a measuring tape, hold the d20 at the appropriate height and measure the distance ground to bottom of the shaft. Cut your dowel to length and maybe add paint and and I suggest some clear varnish or oil to protect it. It's then simply stuck into the shaft bottom, if the fit is too tight, a bit of sandpaper can help to make the diameter of the dowel smaller until it fits. Use the small wood screws to secure the dowel in place. Finally the foot can be added, its just a press fit on the dowel to cap off the end.

AddOns:

I made a shaft head that directly connects to the dowel. So if you don't want to install any lights or have non transparent dice, this is a compact way. It uses the same d20. Find it here.

The dice shop online 55mm d20s are a little bit bigger so I made some extra TDSO holders.

Future sight:

I plan to work on alternative solutions for the LEDs and the battery. The design is made to be modular, so when I come up with a different battery holder I will make it the same connector and this will be happening for all the parts I might change. I'll try my best to find solutions that won't need all the parts to be replaced when I just change one feature.

• Powerbank style, using a 18650 battery and be rechargeable
• using LED strips instead of soldering tiny LEDs 

Alpharelease:

I made a prototype of a battery holder for 18650 batteries and a power bank chip. This makes it possible to charge the cane and don't need so waste batteries. You also get a power bank with your cane and can charge your phone or other devices.

But this needs 5V LEDs, so you either need a resistor within your regular LEDs or you change them for a small piece of LED strip. LED strip is way more convenient to handle as the LEDs are already soldered. Therefore I made a new holder able to fit 8mm wide LED strips. Please check the length between the LEDs when you buy strips, it needs to be around 17mm.