Quote Originally Posted by LambdaFF View Post
There are a series of analysis and explanations on the hydraraptor blog : he investigated that in 2011. Some of the parameters can't be corrected as they are process induced (arc shrinkage) and others are not practical to correct (the cosPi/n correction) so the bottom line (for me !) was to set the diameter I wanted and re-drill after because the general conclusion is that the printed hole will always be smaller than the intended cylinder.
nurbs999: Check out these links that LambdaFF is talking about. I didn't recognize the name hydraraptor, but this blog appears to be written by NopHead. NopHead REALLY knows his stuff!!!

http://hydraraptor.blogspot.com/2011...flow-rate.html
http://hydraraptor.blogspot.com/2011/02/polyholes.html