After breaking up the machine into individual components and dividing out the work, we have come up with an initial design. All parts were created with Solidworks following the guidelines that we highlighted in https://additive-mfg-me.qa.wiscweb.wisc.edu/?p=83 . All values were in millimeters, being careful to have all the dimensions as multiple of the nozzle width 0.5 mm. The very first design is shown below.
We expect some difficulty in assembling the parts as we figure out how much clearance is needed at various locations.
Accuracy depends on the material we will use (ABS or PLA), on the filament diameter and on process parameters that will affect the shrinkage. Resolution, for the machine we will use, ranges from 500 microns down to 50 microns: a tolerance of 0.5 mm or lower will be applied on the hinges, below 0.1 mm on the vertical track slide.
Despite this, it is difficult to obtain a precise prevision of needed clearance and of the tolerances, and therefore to enlarge it and expecting the worse possible condition we will need some post processing. Sandly and hammering post precessing will give us a good fit and a sufficient low friction in the key parts of the trebuchet.