3D Printed MotoMetro!

After months of modifying, breaking, fixing, breaking again, and just generally getting used to my 3d printer, I thought it time to tackle a complex print. I’ve been remodelling the MotoMetro character from my comic/short film Automancy for 3D printing over the past x weeks. I did several scale tests first to see how much detail I could squeeze into a 16cm tall model. It’s definitely taught me a lot. Directly below are photos showing the legs and city details. Check the teenie tiny chimneys, and piping going up the side of the main tower!

Below shows the cranes in the slicing software (separate to modelling, it’s used to export as gcode that the printer can read), next to the finished cranes on the print bed. Each part needed serious consideration so as to incorporate the strengths and weaknesses of FDM (fused deposition modelling) printing. Mainly, this meant keeping a max of 45 degrees on angles, as it can’t print in mid-air.

For the 3D print enthusiasts, I used 1.75mm PLA, extruded through a .4mm nozzle, with 0.1 layer height for finer detail, and 2mm shell thickness for strength (I tend to print very slowly, as I prefer detail over speed). Grid supports were only needed on the exhausts. There’s a few areas I couldn’t quite get the angles to less then 45 degrees when modelling, so there’s a few areas (mainly legs) that the plastic ran a little, but this can be improved before the next iteration. Overall the result was better than I expected, the hydraulics printed out great, and it was an awesome feeling holding the city in my hand (each building was unique and modelled to print at this scale, if you look closely, there’s little crates, barrels and wagons amongst the buildings ^-^).

Printed on a modified Duplicator i3 in four main parts (city, waist block, both legs), and an array of individual cranes, pipes, and exhausts.

And because I’m chronically indecisive, here’s a bunch of closeups. I found it casts a damn fine silhouette when lit from the front and placed in a white shelf, but said shelf has since been filled, though I might add some pics when I next get the chance.

Currently I’m experimenting with a .2mm nozzle, and once it’s working, should produce even more detailed results (the extrusion is as fine as a hair!). This was really more a prototype than anything, and I’ll probably do the next iteration in metallic or transparent PLA. Also considering the possibilities of casting and molding with 3D printed molds, but that’s another story.