Polargraph - timing belt and spring load

My take on a polargraph shown on Aarhus Mini Maker Fair Oct. 2016. Featuring:
1) Spring loaded bearing minimizing/removing belt slip
2) Screw mount (3 parts per side)
3) Suction cup mount (2 parts per side). Mirror parts for mounting electronics on the left hand side.
4) PCB for two steppers and servo (My old EggBot PCB is reused and attached for Eagle)

I used two Alu single suction pad (50kg) from Silverline (http://www.silverlinetools.com/en-GB/Products/Automotive/Bodywork/427574)

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