Sloped bottom tank

A method for forming the bottom of a tank for liquids, said tank having generally upwardly extending sides and a sloped bottom for complete drainage of liquid from the tank, said method comprising the steps of:

• (a) providing a generally flat, rectangular plate member;
• (b) tapering said plate member into a trapezoidal shape with one side of the plate member being longer than the opposite side thereof;
• (c) providing a head forming device having punch and die members, said punch member having at least one raised edge portion;
• (d) positioning said plate member in said head forming device;
• (e) forming said plate member in said head forming device by deforming said flat plate member against said punch and die members to provide a bottom wall portion having at least one downwardly sloping surface and upwardly extending side wall portions which extend continuously around the periphery of said bottom wall portion;
• (f) providing a trim machine having cutting means and plate support means;
• (g) providing said plate support means with a pair of spacer bars mounted on respective adjacent edges of said plate support means so as to form intersecting raised edge portions;
• (h) positioning said formed plate member on said plate support means so that the side of said formed plate member which corresponds to the longer side of the plate member of step (b) is positioned over one of said intersecting raised edge portions;
• and
• (i) operating said cutting means of the trim machine to trim the side wall portions of said formed sheet member.