Humble Electronics #001 - Dice Tower 02 (Summer 2023)

This is a project I finished recently. Many of the other things, I've done this summer, I will post in the coming weeks. 

We own a 10W diode laser cutter and I absolutely love it. One of the things I've cut is a dice tower . I cut out a basic one to see if we wanted one at all. Everyone, in my family, liked it so I cut out a fancier one. This one was really nice from Thingiverse and I changed the flexible cuts to bend better (more on that in a laser cutter post). It was a good base so my husband took it and spray primed it gray. Then he used colored UV resin in the windows. Finally, my daughter did the texture and details. The windows looked great but you couldn't see them very well so I thought I'd add some lights to it.

 

I had some 1206(3216) SMD LEDs and 330 ohm SMD resistors, I got them from Amazon to try some surface mounted soldering, but hadn't used them yet. These were a good choice so they'd stay flush to the sides and not interfere with tumbling dice. I grabbed my smallest through hole prototype board and hacked it into three pieces with a small handsaw. I used Kapton tape to hold the components in place while I soldered from the back. It really wasn't surface mount soldering but it did solder the parts down. Did you know 1206(3216) fit on regular 2.54mm spaced prototype board?

 

 

 

 I soldered a 330 ohm resistor and white LED to each board in series and a positive and negative wire.

 

I tested it with a 5V source and they were good to go. 😁

Installing them into a finished dice tower was not easy. It took some extra wire looped between and tweezers to get them through the hole I had to cut in the dice tumbling ramps. Then I somehow hot glued them in place. I used Kapton tape to secure the wires to the sides so they get caught when the dice go through.

 

Now, I needed a power supply. I decided on a 9V battery because I had several rechargeable ones and clip on attachments. I also recently acquired some SMD voltage regulators for a repair that failed. I picked a 5V regulator I had on hand (AMS1117 SOT-223) and a couple of 10 uF caps , soldered them on the 3rd piece of prototype board and tested it for the 5V output with a multi-meter. It failed even though all my connections tested good. I broke out the magnifying glasses and found a thin hair of wire shorting out the underside. I try to keep a cleanish work surface for just this reason but I must have missed a strand after trimming some multi strand wire. After removing the wire, the output was the 5V I wanted. 

 

Then I realized I needed a switch to leave the battery in place so I added that. It all fit under the last tumbling ramp. I soldered the whole network together with the wires sticking out of the bottom of the tower. I hot glued the voltage regulator board in place, used Velcro on the 9V battery so I could take it out and charge it when needed, and the switch. Et voila! One lit dice tower. 

 

But the lights were harsh so I somehow once again got the tip of the hot glue gun in there and deposited a drop of hot glue on each LED to diffuse it a little. Then it didn't glow as much as I wanted but you could see the windows which was the point so all was not lost.

 

I learned a lot from this project. Point one being to add lights before fully assembled. I'm using 100 ohm resistors on the next one to get more light out and a AAA battery box with a switch to supply 4.5V because this is a gift for a family member. I got some small SMD boards, from Amazon, that are the right size and can hold up to 4 pairs of resistors and LEDs but I'm only going to put 2 sets in parallel on each board. I'd also use 30 gauge wire I have because it's silicone and more flexible or I might use some 24 gauge I have. I will try out different locations for the lights to see if I can get the windows lit better with more access to the inside of the tower.I'm looking forward to completing this next tower.

Here's a schematic made in KiCAD7:

Happy Making!

Michelle