In the Parts Tab of the Data Table the weights of all parts are automatically calculated. Note that when a Part has no material assigned to it, it will not have any weight. To ensure that the weights table is up to date, select Calc All Parts from the Data menu.
Note
Stringer weights are calculated from the volume of the stringer multiplied by the material density. The volume is calculated from the stringer cross sectional area multiplied by the stringer path length. The density is calculated from the stringers material weight per square metre divided by the material’s thickness.