Print accuracy
I have an issue concerning print accuracy:
when I print models having for example cylindric holes as drillings, they are somewhat to small in diameter - around 0.2mm @15mm diameter.
outer dimensions are very accurate.
Also, height is slightly to greater ~ 0.1mm
How can this effects be corrected?
printer MK3.5S
woec
These and other minor distortions, most often of curves, are caused by triangulation and rational approximation when translating ideal dimensions to practical printer movements. Trial and error will usually find an optimal value in a couple of iterations.
Part of the design process is adapting to the quirks of the medium. 0.2mm tolerance, half an extrusion width, is about the closest you can get reliably so scale bearing points, threads and involutes accordingly. Where it really matters design with post-processing in mind. Just as you wouldn't expect a cast metal part to be ready without finishing think of printed plastic as the unfinished penultimate stage.
You can't expect much better than around half the diameter of the standard nozzle, but:
If this is proportional to the dimension then you may just be seeing thermal contraction: is your printer laying down hot plastic accurately - which then contracts as it cools?
Address this with calibration of your original design.
And the usual advice applies when making dimensionally critical blanks, build slightly oversize and machine to fit.
Cheerio,