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Battle for space

 Luckily we live a world with all the 3d printers and advanced manufacturing methods. Luckily, because the production of complex parts is a whole lot easier or even possible in some cases. I could not care much about convexity so important in molding since all the plastics are thought to be 3d printed.
I came out from external shape, and when I tried to fit a pulley for the first time I was shocked how BIG it was! There wasn’t any space left for bearings! Even if it had been I couldn’t have use them because I want to save weight. Alternative option was Igus plastic bearings (compact and lightweight) but they need precise fit. Moreover I wasn’t sure if they would work on plastic. Things went even more complicated when I realized parts of that shapes printed on budget desktop printer would be too weak to bear the twisting forces.

Thanks to CadXpert I had an opportunity to 3d print the most loaded parts from Tough Resin on SLA printer Form 2. The technology itself gives better accuracy and surface finish not to mention stiffness. They need some sanding and polishing but after all worked pretty well with Igus polymer bearings.

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