CNC Aluminum Parts: What Actually Changes Between 200 Pieces and 10,000

When ordering CNC aluminum parts in large quantities, several factors change compared to a smaller order of just a few hundred pieces. Buyers often ask for a unit price at 10,000 pieces, but they should focus on what changes between the two quantities.

At around 200-500 pieces, setup costs dominate the price, while re-indicating every blank becomes unnecessary. Fixturing systems become crucial, allowing parts to move between machines without re-datuming. This pricing structure is influenced by the type of aluminum used, as 6061 and 7075 cut fast and predictably, reducing machine-hour costs. At this stage, engineering judgment is more important than machining, as factors like datum positions, post-stress movement, and anodizing masks impact tolerances.

As the order grows to 10,000 pieces or more, the focus shifts from machining to process design. Dedicated fixtures, tool-life tracking, and in-process gauging replace final inspection for every piece. Some geometry might even be moved off the milling center, with different processes handling specific features. For example, turned features can be sent to lathes, leading to a more cost-effective pricing structure.

The part itself may look different depending on the order size. A typical enclosure living in the few-hundreds-pieces band is made of aluminum with multiple milled faces, and cosmetic consistency (anodizing color match across a batch) is as crucial as dimensional tolerance. When the number of parts increases significantly, the machining moves to the most suitable machine class, rather than doubling the price.

When preparing a Request for Quote (RFQ) for a large CNC aluminum order, it's essential to provide specific details that will lead to a more accurate quote. These include the forecasted order quantities at 200, 1,000, and 10,000 pieces, the alloy and temper used (such as 6061-T6 or 7075-T6), which faces are considered cosmetic, and the Incoterm for shipping.

The EXW Shenzhen shipping method is used by the shop, and they offer recommendations for freight forwarders. It's also worth asking if the buyer will own the dedicated fixtures after the first run, as this can impact the second-order price.