Heatbed calculator remix

I think it will be better with pilot holes for drilling and an outline for cutting out. I also added lines for heat controlling 0805 thermistor.

X,Y are the dimensions of heated area
Steps = number of wires, even integer is recomended
pilot_hole_r is the radius of the pilot holes, helps you to drill (0.2-0.5 mm is OK)
area_r is the safety copper area around holes. Full dimensions will be [x+4*area_r,y+4*area_r], hole-to hole dinensions will be [x+2*area_r,y+2*area_r]
Volt is the voltage