ptmm = 0.04233333;

cylx = 10;

rotate([0,180,0])
difference() {
   cube([1044*ptmm,5+1232*ptmm,6*0.3]);
union() {
// Overlapping metal sheet at top of frame
cube([1044*ptmm,582*ptmm,0.89]);

// Rivets (1.2mm high above sheet)
translate([ptmm*(681+(149/2)), ptmm*(373+(144/2)), 0])
   cylinder(h=cylx+1.2+0.89,r=(153*ptmm)/2,$fn=64);
translate([ptmm*(86+(152/2)), ptmm*(63+(153/2)), 0])
   cylinder(h=cylx+1.2+0.89,r=(153*ptmm)/2,$fn=64);

// Y bar bushing
translate([ptmm*(555+(327/2)),ptmm*(850+(333/2)),0])
   cylinder(h=cylx+1.2,r=(333*ptmm)/2,$fn=64);

// Screw buttons for Y switch
translate([ptmm*(72+(142/2)),ptmm*(862+(148/2)),0])
   cylinder(h=cylx+3,r=(148*ptmm)/2,$fn=64);
translate([ptmm*(67+(145/2)),ptmm*(1090+(142/2)),0])
   cylinder(h=cylx+3,r=(148*ptmm)/2,$fn=64);
}
}