Clock - Test Pieces

Teardown

Well it finally happened, the tape on the back of the clock fell apart and the only way to fix it was to re-tape everything.

Instead of that, I decided to take it off the wall, tear it down, and start printing out some test pieces.

I also replaced the existing buck converter with a shorter one so the clock wouldn’t be as thick.

Here are all of the parts together, along with the test pieces that I printed out:

Raspberry Pi Zero W

The Raspberry Pi Zero W (bottom left) is a simple little computer that does a lot of the work to make this clock work.

I’ve installed Linux on it and created a simple script to open a browser, go to a specific web page, and go full screen once the device has been powered on.

Right now it goes to a web page that’s sitting on my server. As part of this upgrade, I plan on hosting the code directly on the Raspberry Pi (probably using nginx).

HDMI Input LCD Controller Board

The controller board (bottom right) is a simple board that takes an HDMI input and outputs it to the laptop screen.

12V to 5V DC Buck Converter

The buck converter (middle) is needed because the Raspberry Pi runs on 5V DC but the HDMI controller board runs on 12V DC. So all it does is step down 12V DC to 5V DC.

Without this, I would need two different power plugs to power the clock.

With a barrel plug splitter and an old micro USB cable, I can have the whole thing running off of one power supply.

The power supply I’m using converts 120V AC to 12V DC, which allows me to just plug it into the wall.

Printing the test pieces

First, I sketched out each part and wrote down the dimensions needed:

Then I drew up each part in Fusion 360:

And then it was just a matter of printing them all out and testing the fit. As you can see in my sketch above, several components didn’t work out as planned and had to be adjusted.

But I eventually tuned them to fit as needed, and I’m pretty happy with the results so far.

I did notice one problem during the printing, I think the nozzle is pushing against the print bed too hard. I’ll be sure to re-level the print bed before printing out the final case.

Raspberry Pi

Controller

Buck Converter

Corner

The corner test piece was used to make sure it fairly flush with the edge of the laptop screen.

Connector

Since my print bed is only 220x200 mm, I’ll have to print the case in at least two parts.

Next Time

Next, I plan on finishing up the final design and printing the whole case out. I also need to write up the code for the clock website itself.