deadlime

Did I just print that for the sake of a pun? Maybe...

I've been thinking about getting a 3D printer for a long time, but I wanted something closer to the end-user experience, like a 2D printer. I didn't want to start building 3D printers as a hobby, I just wanted to print.

Then I discovered Bambu Lab's printers, which seemed to be just like that. I was hesitating between the A1 and P1 product lines, finally settling on the A1 (without the AMS lite), thinking that as a first printer, the cheaper one would do. The main difference is that it is not recommended to print ABS with the A1, but for now, that doesn't really bother me.

Obviously, when it arrived I printed out all the silly things I could download from the Internet, but one of the reasons I convinced myself I might need a 3D printer was so I could print parts for my little hardware projects. One such project is the Pico-based clock, which hasn't changed much in software since then, but now has a half-baked box. Let's have a look at how it was made.

Design

I'm quite familiar with Blender, so I started to put the box together using that, but I probably would have been better off learning some CAD software instead. It's not impossible to do this kind of thing in Blender, but it's not what it's designed for.

Click for the bigger picture!

I also searched for my old digital caliper, but the digital part wasn't working anymore (luckily it still worked as an analog caliper), so I couldn't measure things accurately enough.

Execution

First, I printed a frame around the display... then a couple more, because of the measurement problems mentioned above.

You can't really see the differences with the naked eye. I adjusted tenths of millimeters (that's like 4 thou for the US folks out there) until I finally got the exact fit.

The next step was to place the buttons. At first, I thought it would be part of the printed case, but the buttons were too small and the PLA isn't suitable for this kind of use.

Once the buttons were in place (I made about 3-4 versions of them to fit the holes properly), I had a roughly finished front element that fit the electronics perfectly.

Now the back half. Here I had multiple problems with the holes for the screws.

I was planning to put threaded inserts in the front, the screws would have just gone through the back, but the package didn't arrive in time, so I ended up with holes that were small enough that the M2 screws can cut the threads for themselves. This will do for the first version.

The other problem was the position of the holes, they had to be in the same place as the holes in the corners of the PCB to eventually screw the two parts together.

Same deal as with the display frame, but in this case my first guess was about half a millimeter off. In the end, I had to cut a bit more off the corners, because the back was too high for my longest screw to reach through.

Next came the USB location. For this, I just printed a small part of the back again and again until I found the exact position.

After the first version, I also cut back on the details to reduce printing time.

And here we are with the first version. It's not that good-looking, but all the measurements are right, and I'll be able to make it more pretty in the next version if I can still make sense of the Blender model.

Although you can't see it in the picture, there's a small hole under the USB, through which you can also reach the LiPo SHIM on/off button.

The buttons got small lettering, but the 0.4 mm nozzle couldn't handle it properly.

The familiar retro backlight and last year's fake interface.

All in all, 3D printing is great fun, what I might do differently in hindsight is not to start without a working digital caliper to produce less plastic junk during the project. And I'd try to get myself to take a closer look at some CAD software.