The costing of turned components at the design stage

A costing system has been evolved for turned components produced by a variety of machines; the system is based upon a fundamental cost equation which utilises in the main, the manufacturing time of the component, together with its material cost. A technique for predicting the floor to floor time, Ft, has been established based upon the size and shape of the component in parameters readily available to the designer. The generally accepted setting times for various machines have been corrected to take into account the component complexity. In estimating the material requirements, allowances have been made for material wastage, due to schedule or quantity change, scrap losses and the effect of the operator learning curve on these losses. A graphical presentation of the floor time equation enables the designer to rapidly assess variations in Ft, if he chooses to vary one, or indeed all of the parameters within his control, i.e. material, finish, size, features, etc., etc. in order to meet a certain cost target.