Wesley's Tool-Box

I've been downloading and 3D printing a lot of interesting stuff so far. But eventually, I had to tackle the art of using a 3D modeling program to create custom designs. For my first attempt, I decided to make a coin with a logo on its face. Specifically, the logo was that of KPX, which is where I work. As far as I am aware, the company never issued a commemorative coin before, so it seemed to be a good choice.

A few weeks ago, I had installed Autodesk's 123D Design software to make 3D models. I was originally thinking of TinkerCAD, but that had been bought by Autodesk, so I thought I might as well just use Autodesk's original software. Apart from being slow to load on my Mac, it was thankfully not too difficult to make some shapes and move things around.


After a couple of practice, I started drawing the KPX logo. Sadly, there wasn't a way of importing an image file to trace over. As a workaround, I put a grid over an image of the logo and drew the lines as closely resembling as possible on the grid within 123D Design. It came out fairly well.

My kids wanted bigger cars from the 3D printer because the ones I made were too small. So I wanted a design that maxes out the print dimensions, while being somewhat special. That's why picked this balloon-powered car. I initially tried the design that uses snap-on wheels, but seeing that the wheels may not turn smoothly, I went ahead with the one that needed separate wires that held the wheels. To see how this went, read on.

One of the fun things about 3D printing is that, with a clever design, you can have movable parts already inside the printed object. One fine example is having captive wheels inside toy cars, like the ones you see here. No assembly is required - they are already inside the main body and can freely turn after scraping off some excess materials unintentionally introduced during the print. Here is the video of them in action.

My Makibox 3D printer was doing very well up to early this month. But then suddenly, it decided to stop pushing the plastic filament into the extruder. After some manual pushing, it worked again for a while, but then it'd stop yet again. Looking at the filament, I saw some grinding, so I initially suspected a clogged nozzle. But if I disengage the filament from the feeder and push the filament in by hand, the nozzle had no problem putting out the material. So I took the filament feeder apart.

Now, Makibox's filament feeder is called "Zen Drive". It consists of a stepping motor with toothed axis and a tension wheel. The teeth "bites into" the filament to make it move, while the wheel allows the filament to catch onto the teeth in a consistent manner. When I disassembled the Zen Drive assembly, I noticed that two of the wheel's spokes had snapped. Snapped spoke meant that a consistent pressure couldn't be applied to the filament. This was the cause of the inconsistent filament feed I experienced. It was time for a repair.

Musical instruments must be shaped and tuned right to have proper sound coming out of them. If a 3D design of an instrument is shaped right, a 3D printer that can accurately reproduce it would make a properly working version, then. Makibox had been working reasonably, provided that I don't push it too far. So I wanted to see if it was up to the challenge. The result is what you see here.

Looks alright, doesn't it? But can it make any sound at all? I'll let you see (and hear) for yourself with this video.


Read on to see the steps taken to make one.