For the prints, use ASA. It has a strong tendency to warp on the base, but as long as the warping is even, it doesn't impact the functionality much. I used 3DXTech Black and Yellow ASA.
For the hardware, go with stainless steel. They're on wheels, so they will be exposed to the elements.
For the bearings, I would recommend Senston ceramic bearings, available here:
https://www.amazon.com/gp/product/B08ZN94S5L/
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Printers
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* Heavily-modified 8" dual-extruder machine that started its life as a MakerFarm i3v. Most of the parts on it have been replaced with improved versions.
* Large format machine similar to a C-Bot.
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Materials:
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