radius_gauge.scad

$fn = 100;

module radius_gauge(min_radius, max_radius, radius_step, vertical_step_size, padding) {
    gauge_side = max_radius + padding;
    vertical_step_count = (max_radius - min_radius) / radius_step;
    gauge_height = vertical_step_count * vertical_step_size + 2*padding;
    
    difference() {
        cube([gauge_side,gauge_side,gauge_height]);

        translate([0,0,padding])
        for (i = [0:vertical_step_count]) {
            radius = min_radius + i*radius_step;
            zpos = i*vertical_step_size;
            translate([0,0,zpos])
            cylinder(r = radius,
                     h = gauge_height);

            d = 0.5;
            
            translate([radius + 1,d,zpos])
            rotate([90,0,0])
            linear_extrude(height = 2*d)
            text(str(radius), size = vertical_step_size - 0.1);
        }
    }
}

radius_gauge(
    min_radius = 2,
    max_radius = 20,
    radius_step = 0.5,
    vertical_step_size = 2,
    padding = 10
);