30 cube(psz + 2*thick - [1,0,0] * (thick[0]));
32 for (yp= [ btn_yprop, 1-btn_yprop ])
36 cylinder(r= btn_dia/2, h=20);
43 translate([0,ym,0]) mirror([0,m,0]) translate([0,-ym,0])
44 translate([-1,-1, psz[2]-rail_zsz])
45 cube([psz[0]+1, rail_ysz+1, rail_zsz+1]);