This appears to be a bug but if there is a workaround I would love to know!
In Print->Linetypes and Line Widths I changed the line width from hairline to .50mm which only changed the printed line widths of a few random lines (mostly dimension lines and one or two curves - but not all curves.)
I tried changing the line width back to ‘hairline’ without success. The line width is now permanently stuck to .50mm. Now printing is essentially useless.
Changing the line thickness number in PrintDisplay does nothing. (This number doesn’t seem to correspond to any particular measurement system. The default is 40 but I can’t figure out in what kind of unit that is referring to.)
Steps to hopefully reproduce (same for Rhino 5.3.1 and RhinoWIP):
In the print dialog change the line width to .50mm.
Printed line widths seemingly random between .50mm and hairline.
Set line width back to ‘hairline’.
Print. No change in print output.
Back to print dialog, line width still mysteriously set to .50mm
No amount of changing back to ‘hairline’ or any other width makes a difference.
PS. It would be great if line widths could be set in points as well as mm.
Rhinoceros version: 5.3.1 (5D193)
IronPython version: not installed
Language: en (MacOS default)
macOS version: Version 10.11.6 (Build 15G1217)
Third party kernel extensions
com.paragon-software.filesystems.ntfs (288.2.14) 45BD8A05-DF87-3335-89C6-41776D72ABD2
Hardware model: MacBookPro10,1
Processor: Intel Core i7-3615QM CPU @ 2.30GHz
Memory: 8 GB
Architecture: Intel 64 bit
Graphics: NVIDIA GeForce GT 650M 1024 MB
Memory: 1024 MB
Screen size: 1440 x 900
Displays: Color LCD (221dpi 2x)
Apple Inc.: FaceTime HD Camera (Built-in)
Apple Inc.: Apple Internal Keyboard / Trackpad
Apple Inc.: Bluetooth USB Host Controller
Seagate: BUP Slim SL
SanDisk: Cruzer Glide 3.0
OpenGL version: 2.1 NVIDIA-10.10.14 310.42.25f02
Render version: 2.1
Shading language: 1.20
Maximum texture size: 16384 x 16384
Z-buffer depth: 24 bits
Maximum viewport size: 16384 x 16384
Use texture compression: No
Mip map filtering: None
Anisotropic filtering: None