Why are there tooling charges for a flex circuit?
As with a rigid PCB, it is common for non-recurring engineering costs to be applied when designing and producing a flex circuit. Non-recurring engineering (NRE) refers to the one-time cost to make the tooling to produce the flex circuit.
Manufacturing flex circuits, rigid flex and flex assemblies involves the development of different tools that will require a one-time charge. On your initial quotation from PFC, you will see NRE charges.
PFC offers its customers: soft/basic tooling for low volume and prototype runs, and hard tooling for larger production runs that require longer tool life or precision tolerances. The cost of the tooling is dependent on the type and the design of the tooling so careful assessment is very important to prevent quality issues and to minimize the costs.