%!PS-Adobe
/mm { 72 mul 25.4 div } def
/sin15 0.258819 def /cos15 0.965926 def /tan15 0.267949 def
/sin30 0.5 def /cos30 0.866025 def /tan30 0.57735 def
/sin60 0.866025 def /cos60 0.5 def /tan60 1.73205 def
/sin75 0.965926 def /cos75 0.258819 def /tan75 3.73205 def

/balldiam 74 mm def
/ballradius balldiam 0.5 mul def
/thickness 6 mm def
/holeradius ballradius dup mul ballradius thickness sub dup mul sub sqrt def
/clearance balldiam 0.7 mul def

% print instructions ...
/Times-Roman findfont 10 scalefont setfont
100 mm 264 mm moveto (Plinth, 6mm plywood,) show
100 mm 260 mm moveto (for ten balls of 74mm diam) show
100 mm 256 mm moveto (see http://www.pjb.com.au/jug) show

/oneside {
   newpath
   0  balldiam cos30 mul ballradius tan30 mul sub 2 mul 1.5 0 360 arc fill
   0  balldiam cos30 mul ballradius tan30 mul sub 2 mul
   holeradius 0 360 arc stroke

   0  balldiam tan30 mul -1 mul 1.5 0 360 arc fill
   0  balldiam tan30 mul -1 mul holeradius 0 360 arc stroke

   0  balldiam cos30 mul ballradius tan30 mul sub 2 mul
   clearance 30 150 arc stroke
   balldiam -1 mul  balldiam tan30 mul clearance add -1 mul moveto
   balldiam  2 mul 0 rlineto stroke
} def

/plinth {
   gsave 30 rotate oneside 120 rotate oneside 120 rotate oneside grestore
} def

100 mm 135 mm translate plinth
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