Lamp shade from analytic expression
Lamp shade made from an analytic expression using this Mathematica code in case of #1:
ParametricPlot3D[ {If[z > 0, Cos[z], Exp[z/5]]* (Cos[u] + (1 + Tanh[z + \[Pi]/2])*(0.13 Sin[5 (u + z)] + 0.01 Sin[2.5 (u + z)]^2)*0.4 Cos[z]^2 + (1 + Tanh[z]) Cos[ 15*z]*0.05), If[z > 0, Cos[z], Exp[z/5]]*(Sin[u] + (1 + Tanh[z + \[Pi]/2])*(0.13 Cos[5 (u + z)] + 0.01 Sin[2.5 (u + z)]^2)* 0.4 Cos[z]^2 + (1 + Tanh[z]) Sin[15*z]*0.05), z}, {u, 0, 2 \[Pi]}, {z, -0.8 \[Pi], \[Pi]/2}, PlotPoints -> 200] Print using e.g. vase option of slic3r or with a single wall. #2 is designed for smaller overhang angles.