Trying to print a pulley - motor shaft size

I’m trying to print this which I created using the ‘Customizer’.
When I check the stl file in Sketchup the dimensions look correct but after slicing with Cura & printing the bore for the rod is too narrow. I defined it as 8.2 but it finishes around 7.6 or so. Could this be due to a setting in the slicer, or printer alignment. The other dimensions look very close.

It’s usual that the holes are printed too small. I’s a slicer/printer issue with circles. You always have to over-scale them in your designs (about 10%) especially when they are printed on the bed plane. And the smaller the hole the greater the imprecision. So it’s interesting to print a hole calibration tool like this one :

Isn’t the normal shrinkage rate? Might be slightly high, but if you scale your model by one or two percent it should get closer. The problem with shrinkage is that it’s uneven, so holes and slots can shrink out of shape depending on the amount of material around them, the position / direction of the fans, etc.

Hmm, maybe my idea to print replacement pulleys for the Vertex is not so clever viewtopic.php?f=63&t=13367.