Digital Light Pipes Fiber Optic Clock

Inspiration for this clock struck 6 months ago after seeing @ItsMrJP 's awesome hot air balloon prints. I wanted to build something functional that would highlight the beauty of the thick side glow fiber optic pieces. Originally I though of enclosing the clock so the pipes couldn't be disturbed, but after much trial and error, I decided to keep the back open for a clear view of the strands. 

After posting some initial sketches on Twitter I got some very valuable advice and feedback from @maketvee and @ItsMrJP. Thanks to these guys for their help!

So, how to make it. Lets get to it.

Below are the parts, materials, tools and software needed. I have included Amazon links for convenience, but the parts can be found elsewhere, probably cheaper.

• Parts & Materials
• White and black filament (tested with basic PLA, results with other materials may vary)
• 2 10ft PMMA Plastic Optic Fiber Side Glow Cable for LED Light Source (0.12in) https://www.amazon.com/dp/B07R47L56L?psc=1&ref=ppx_yo2ov_dt_b_product_details
• 1 8x8 64 bit WS2812B 5050 RGB LED Matrix https://www.banggood.com/CJMCU-64-Bit-WS2812-5050-RGB-LED-Driver-Development-Board-p-981678.html
• 1 ESP8266 D1 Mini https://www.amazon.com/gp/product/B073CQVFLK/ref=ppx_yo_dt_b_search_asin_title?ie=UTF8&psc=1 
• 1 Micro USB data cable
• 1 MPU-6050 https://www.amazon.com/gp/product/B07W3S7X7W/ref=ppx_yo_dt_b_search_asin_title?ie=UTF8&psc=1
• 1 M2x6 screw
• Jumper wires (recommended red, black and 3 other colors)
• Tools
• Soldering Iron & Solder
• Wire strippers
• Snips (optional, for post processing 3d printed parts if needed)
• Hot glue gun (optional, may be helpful in keeping parts still, and shielding exposed connections. 
• Screwdriver
• Software
• Arduino IDE
• A slicer program for 3d printing (Cura)

Print the below parts as is. No supports necessary. Stl files already have the correct orientation. 

• base.stl - print 1 in black
• face.stl - print 1 in black
• underside_lid.stl - print 1 in black, recommend using a brim
• lens.stl - print 28 in white

Using Arduino Ide flash the code to the ESP8266 board. Make sure to update the wifi SSID and password first! This code is a slightly modified version of the ClockSketch V7 by Parallyze. The code is highly configurable, so play around with it if you like, but the version I have posted on github is modified to work with this clock specifically.

See above for circuit schematic and parts placement on the 3d printed underside_lid piece.

Secure the MPU6050 with the M2x6 screw, and slide the ESP8266 into the slots. Hot glue may be used to hold down the ESP8266 a bit firmer, but once the led matrix is on and the underside_lid is popped into the base, this part will not move.

When soldering the wires to the MPU6050 and the ESP8266, have the wires come out the underside of the boards. There is a gap built in to allow the wires to go through. If they are wired on top, the led matrix won't have enough space.

Make sure the led matrix wires line up with the gap in the underside_lid that allows the wires to go through without lifting the matrix. The matrix should sit flat on the rails of the underside_lid.

Once the parts are soldered and positioned, test the circuits by plugging it in. Also test the gyro by turning the piece upside down to change the color pallet.

Once the parts are soldered, positioned and tested, slide the underside_lid up into the base piece. Line up the oval opening with the usb port of the ESP8266, then push slightly up into the base. It shouldn't need to be forced, if it is too hard to push, check the parts arrangement and make sure nothing is in the way. You should hear a few clicks when the underside goes into the base correctly.

If you need to pull the parts back out of the base, pinch slightly on the sides of the underside_lid and pull down and back out.

Slide the face piece into the base. The tab sticking out of the bottom should be inserted toward the light grid. If inserted correctly the face should sit flush with the base, forming a L shape.

Next start cutting up the PMMA. I recommend cutting as you go. The lengths are not exact, but slightly longer than needed works best. When the pieces are too short they will not have tension on them and they will fall out. The spreadsheet image above lists out approximations for the lengths of each row and how they should be plugged in. I have highlighted a couple to get started. For reference, the green 0 at the back corner of the grid lines up with the green zero at the top left of the first digit. The yellow 7 at the front of the grid, closest to the face, aligns with the bottom right of the last digit. And so on.

When inserting the PMMA into the lens pieces, push the strand in but don't force it all the way. It should "catch" about half way through the piece, and should be slightly difficult to pull back out when tugged.

Start with the bottom, the row closest to the face. And work your way up/out.