issue with lower layers of spherical / round objects
Good Morning.
After assembling my kit, I made some test prints that pleased me, except the objects with round parts. In the lower layers of these objects the print quality becomes very poor.
I've tried several support configurations (including not using them) but got no improvement.
I would appreciate suggestions on how to improve this.
I used in this print the "0.10mm DETAIL MK3" default setting of PrusaSlicer (just changing the supports option to "Everywhere") and Prusa PLA Filament
I know that in this case I would get a better result by cutting the sphere and printing in two parts, but this solution cannot always be applied.
Thank you very much
RE: issue with lower layers of spherical / round objects
Gravity is your problem and the limits of FDM printing.
The shallower the angle to the base the further the next layer is overlapped over the previous layer.
eg if you print straight up you stack the layers neatly one directly above the other, and the layer above is squished into the layer below.
At 45 Deg, the layer above is placed half sticking out over the layer below and only half can get a proper squish as half has nothing supporting it.
at 67.5 Deg (or 22.5 from the flat), your only a quarter on the layer above and 3 quarters of the strand has nothing supporting it and after that it just gets less and less possible to get anything to stick together and keep some form of shape.
A sphere cannot be printed without issues without supports on an FDM printer.
You could try the variable layer height modifier and print really thin layers to begin with as these should overlap a bit more, but even with this there will be a point underneath where you really are trying to defy physics without any supports. Or maybe even try much thicker layers to limit how many layers are printed in that first bottom 20 degrees of print, but obviously your levels of detail will suffer.
Normal people believe that if it ain’t broke, don’t fix it. Engineers believe that if it ain’t broke, it doesn’t have enough features yet.
RE: issue with lower layers of spherical / round objects
Hexagon supports may work better than say rectilinear, but only use them up to about 20 degrees height, it is worth playing around with the settings for spacings and distance, I found sometimes I can get better results with wider spacing and slightly larger contact distances or whatever they are called, I'm not near my printer PC so don't have access to slicer to see, but it really is worth playing with the settings, I found leaving things in auto, just ends up leaving too many scars on the finished print.
Normal people believe that if it ain’t broke, don’t fix it. Engineers believe that if it ain’t broke, it doesn’t have enough features yet.