Thread lead plate

This part is produced using a progressive die with a complex hook shape featuring multiple different bend radii (R1, R2, R3, R5, R6) connected into a smooth curve, requiring high precision at each station to prevent cracking or deformation at the radius transition points.

The triangular/teardrop hole at the hook tip and the slotted holes at the base must be precisely positioned so that, once installed in the sewing machine, the thread path doesn’t shift and cause thread jams or breaks during operation.

After stamping, the part undergoes vibratory deburring and nickel plating, so the plating must be controlled to coat evenly even into the tight corners of this complex curved shape.