Okay perhaps I am not understanding something here but I have a basic issue with this as it appears to be a circular reference and even if it is not it is very confusing code.
scale = Scale(... command = mod_calc) def mod_calc(w1) : slider_value = scale.get()It appears your mod_calc is defined using scale and your scale is defined using mod_calc begging the question -- which comes first the chicken or the egg