Tolerance test

Note this is an import from: https://www.thingiverse.com/th... The import messed up the formatting. Updates occur on Thingiverse. Summary Designed as a test of tolerances for 3D printing. Inspired by my own (mis-)adventures learning the CAD (Onshape), slicer (Cura), and 3D printer (Monoprice Maker Select Plus) workflow - and also a Maker's Muse episode:

To do this exercise properly, you need to update parameter(s) in the model to match your printer (which is really not how this should work, but). Will write this up as a weblog post, at some point... In my latest (versioned in Onshape) iteration, got down to 0.2mm in gap between parts, with a parameter in the model, which ... is quite wrong. The parameter should be part of the printer profile given to the slicer. Still. From the Document Description (in Onshape): The #overfill parameter is used to adjust the amount lines of plastic laid down by an additive 3D printer are a bit wider than where the plastic is meant to land. For example, a 12mm circle (in the x-y plane) when printed on my current printer measures a bit over 12.1mm, so I set #overfill to 0.1mm (for my printer). This #overfill number should be zero (the CAD model should not have adjustments for the printer). But the state of the art with 3D printers is not that advanced. (In fact it is much like using on-paper printers in the 1980s and 90s.) The clearance between each cylinder and the frame varies between 0.1mm and 0.7mm, in steps of #dxy_gap (which is set to 0.1mm). If you have an ultra-precise printer, you might try a smaller #dxy_gap value. On my printer I can free all but the last cylinder, and the gap between cylinder and the frame is close to what is specified in the model. I suspect the #overfill value varies with temperature, layer height, filament, extrusion speed, etc. But ... have to start somewhere. :) How I Designed This Created in Onshape https://cad.onshape.com/docume...