One feature present in each lamination, except the first (usually called the “end”) lamination, is an interlock feature(s). The interlock tabs, or bosses, may be shaped and located as required. Each interlock feature extends from one lamination to enter the adjacent lam below, and thus each subsequent lam is locked together in a stack. The “end” lamination has an opening to receive an interlock, but has no interlock feature to extend into the lam below it. Hence, it keeps the stack it is attached to from locking to the stack immediately below it. In that way, stacks can be produced sequentially and continuously, keeping the choke station constantly filled with parts, essential to generating the consistent back-pressure needed to interlock parts together.

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