Building a 3D printer (part 1)

Introduction

After some misadventures with 3D printed miniatures, a group of friends decided that we need a 3D printer. I joined in. Suffice to say, things got way more complicated than we expected.

Purchase

I volunteered to do the purchasing part to get our hands on this Tevo Tarantula. It was the first time I bought something expensive from China, and had to endure the customs operations. I paid a moderate fee to the delivery company to handle most of it, and I have to say it was totally worth it.
This was in January.

Pause

The guy who was supposed to store it ran into some difficulties, so we had to pause the project. For 4 months. Eventually, the printer was assembled and stored for a while at my place.

Assembly

Unlike regular printers, these things do not come ready-to-print out of the box. So two of us sat down to assemble it in a weekday evening. I mean two engineers, having both the physical manual and this helpful youtube tutorial with a length of 1 hour 25 minutes can totally do that in an evening, right?

Right?

Wrong.

After about 2.5 hours, we progressed 23 minutes in the video. We assembled the superstructure - and that was it.

On the second evening (another 2.5 hours), we progressed 40 minutes in the video. Huge thanks to the girls who helped along during the previous session by unpacking and cleaning up the plastic plates, as well as pre-assembling components. We had the mechanical parts mostly ready, except one part where the provided screws seemed too short to work.

Seeing as this would take forever, we took a whole Saturday afternoon for the next session. We worked on the thing for about 7 hours, well into the evening (although we did snack and downed a couple of beers through the duration), including a shopping trip to buy proper screws. We had completed the assembly, including all the electrical wiring. It was time to test the machine!

... Well, it was underwhelming, to say the least. The plate that was being printed on wobbled like hell. We interrupted the test print after observing that the layers were not placed properly atop each other. Yes, this is what the machine made for us:

Part adjustment

Another Saturday afternoon. This time, there were 3 of us (although on this particular day I was thoroughly tired and sleepy, and did not contribute much, except serving the snacks and drinks). The wobbly plate was taken apart. We realized that we don't have enough spare parts to fasten it back, so it was time for another shopping trip. The guys then used precision tools and a drill to re-position some of the screws that hold the plate in place.

Behold the glorious test model:

Of course, this was not the end of it. The plate that was supposed to secure the print head also wobbled a little - we didn't notice this at first, due to how much the other part wobbled. Whenever the print head did a sharp stop, the head was jerked and the layer was interrupted. Another 5 hours down the drain (not counting dinner). Although, to be fair, for the final 30 minutes, we just sat there, mesmerized, looking at the printer laying layer after layer, forming our little tugboat.