title helix
quadratic
cylinder 1 5;1 226;1 5;1.5 2.5 0 900 -.5 .5
sfi -1 -2;1 2;-1 -2;ts 0 0 0 0 0 1 2 0 1
z=z+0.05*j
endpart merge
rx 70 zf 1.5 tvv
