Metals & machining: sourcing questions answered
3 categories in this group, each with sourced answers on minimum order quantity, tooling cost, lead time, unit cost, HS classification and import duty.
CNC machining and metal parts
CNC machining has no tooling cost, which makes it the right answer for prototypes, low volumes and geometry that will still change. The trade-off is a high unit cost that falls slowly with volume, so for anything above a few hundred units it is worth comparing against casting or moulding — and it is worth saying plainly that at 200 units, machining a part can easily cost more per unit than a mould would cost in total..
Die casting and metal forming
Die casting, forging and stamping are the processes where a Chinese factory's scale genuinely beats anything available to a small buyer domestically — but only above volumes that justify the die. Below a few thousand units the die cost dominates and the arithmetic fails, and saying so early saves the buyer a wasted tooling payment..
Custom hardware and fasteners
Hardware looks like a commodity and behaves like one until a finish or a tolerance is specified, at which point the price moves. Screws, brackets, hinges and fittings are cheap per unit and expensive per mistake, because a defective batch of ten thousand is discovered by the customer rather than in inspection..