// This document uses MILLIMETRES as a unit. // Set $fs (smallest arc fragment) to lower value than default 2.0 $fs = 0.5; // millimetres // Minimum angle $fa = 3; // degrees rotate_extrude() { import (file = "lamp1.dxf", convexity=4); }; translate([0,0,-2.9]) difference() { cylinder(r1=17.5, r2=18.5, h=3); cylinder(r=16.5, h=5); };