Pre-hard vs through-hard: which workflow, when

A shop running a small-press operation orders three hot-forge inserts. The buyer specs pre-hard H13 at 42 HRC because the stock is on the shelf and the lead time is short. The dies run for 18,000 cycles and start cavity-washing at the corners. The replacement run goes out as through-hardened H13 at 50 HRC and runs 95,000 cycles. The pre-hard call cost the shop most of a year of die life to save two weeks of lead time on the first build.

The pre-hard versus through-hard decision is one of the cleanest engineering trades in forge die work. It is also one of the most commonly defaulted, because the pre-hard stock is on the shelf and the heat-treat cycle looks like added scheduling. Neither framing tracks what the die actually does in service.