Hi all,
Apologies if this is trivial, but it’s driving me up the walls 
Can you change the line thickness in Rhino 6? If so, how?
Thank you so much for any help
Ren
Assuming you are asking about the display of curves on the screen, go into Preferences/Settings > Display Modes > choose the display mode that is bothering you, and change the edge thickness for Surfaces on the General tab, and the width for other things in the Objects tab.
Thank you