Method and apparatus for tolerance trimming and piercing workpieces

Claim 1

THE METHOD OF TOLERANCE TRIMMING WORKPIECES COMPRISING FORMING A WORKPIECE OF COMPOUND CURVATURE IN A PIECE OF SHEET METAL MATERIAL SUCH THAT OVERSTOCK EXTENDS LATERALLY OUTWARDLY FROM OUTER PORTIONS OF SAID WORKPIECE, PROVIDING A TRIMMING FIXTURE HAVING AT LEAST ONE PAIR OF SEPARATE TRIMMING EDGE PORTIONS THEREON DEFINING SUBSTANTIAL PORTIONS OF THE DESIRED FINISHED OUTER DIMENSION OF THE WORKPIECE TO TOLERANCE, PLACING THE WORKPIECE WITH THE OVERSTOCK THEREON IN THE FIXTURE AND CLAMPING OUTER PORTIONS OF SAID WORKPIECE BETWEEN FIRST SURFACES OF SAID EDGE PORTIONS WHICH CLAMPINGLY CONTACT OPPOSITE SIDES OF THE WORKPIECE SUBSTANTIALLY CONTINUOUSLY ALONG SUCH FIRST SURFACES, SECOND OUTWARDLY FACING SURFACES OF SAID EDGE PORTIONS LYING SUBSTANTIALLY IN A PLANE, AND REMOVING THE OVERSTOCK PROJECTING BEYOND SAID SECOND SURFACES BY MANUALLY MANIPULATING SEPARATE PORTABLE TOOL MEANS HAVING A CUTTING PORTION THEREON AND MOVING SAID CUTTING PORTION ALONG SAID SECOND SURFACES TO CUT THE OVERSTOCK FROM THE WORKPIECE.