// basic example of OpenSCAD that makes a plate that has holes in it
// you can export this to DXF because it makes 2D projection

module test()
{
// difference = first “object” is cut out with the rest of the objects
difference()
{
// union = all shapes inside union becomes one
// in this case this is the first object
union()
{
cylinder(r=30, h=3, center=true);
cube(size = [100,30,1], center = true);
}

// ok, let’s then punctuate the cylinder+cube combo with holes

for ( i = [0:10] )
{
rotate([0,0,36*i]) // rotate the “world”

translate([25,0,0]) // move away from the center
{
cylinder(r=2, h=5, center=true); // punch a hole
}
}

}
}

projection(cut=true) test();