CaliCross

thingiverse

Every time someone fine-tunes motor steps with a 20mm cube, a 3D Benchy goes down for the count!\nI created this object to reliably check the calibration of your steps, general inner and outer widths, and fittings for square and round holes.\nIt's too big for continuous printing, but that's required to have a reliable and "real world" source for measurements. It's not meant as a stress test; if it doesn't print well, you'll definitely run into problems with real objects!\nThe main cross structure is 200 mm x 200 mm with 40 mm wide legs.\nThe wide holes are 80 mm long x 10 mm wide.\nThe distance of the inner hole to the outer side of an arm is 15 mm ((40-10)/2).\nThe distance between the wide hole and the outer perimeter of an arm is 95 mm (100-10/2).\nThe center hole diameter is 20 mm and should be perfectly round.\nThe round and square holes are 2, 3, 4, 5, 6, 7, 8 mm wide.\nThe heights of the cylinder and cubes match their widths. \nThe height of the whole cross is 1.6 mm.\nThe axes are labeled Y0 Y200 X0 X200 to identify the orientation after the print finishes.\nThe order of different elements is chosen so you can measure them easily with a caliper.\nThe additional holes in the center are just for cutting the object into four pieces, because you can.\nI hope it will help check and calculate your calibration for X and Y axes separately. Especially showing the difference in step (hardware) and extrusion related (flow / width) calibration. If your differences between different sized objects of one axis aren't proportional to the length of the measured vertices, you can be pretty sure that it's not steps-related. It also lets you estimate the sizes you need for a quick and dirty scale to fit.\nTo learn how to really calibrate your printer, I suggest reading:\nhttp://reprap.org/wiki/Triffid_Hunter%27s_Calibration_Guide\nhttp://www.thingiverse.com/thing:52946