Volume decides your manufacturing process more than any other single variable. Under about 100 units, avoid dedicated tooling entirely — 3D print or machine the parts. Around 1,000 units, low-cost tooling starts to pay: urethane casting, aluminum bridge molds, and sheet metal. Around 10,000 units, conventional steel injection molds and die casting become clearly cheaper per part. Above roughly 100,000, the optimization shifts from choosing a tool to shortening cycle time and automating labor. The exact crossover depends on your part, but the logic behind it is always the same.
The math in one line
Total cost equals tooling cost plus per-part cost multiplied by quantity. That is the whole framework. Tooling is a fixed investment amortized over your run; per-part cost is what you pay every time.
Processes with expensive tooling have cheap parts. Processes with no tooling have expensive parts. The crossover point is where the two total-cost lines intersect, and finding it for your specific part is a spreadsheet exercise, not a guess.
One warning that trips up nearly everyone: the crossover is not the whole decision. Tooling also buys you tighter tolerances, better surface finish, and material properties you cannot reach any other way — sometimes you invest in a mold at low volume because the part cannot be made acceptably otherwise.
Up to 100 units: no dedicated tooling
At this volume, tooling amortization dominates everything. Spending five figures on a mold to make fifty parts is almost never rational.
- 3D printing — the default for plastic parts. No tooling, geometry freedom, days of lead time. Per-part cost is high and finish needs work, but for pilot runs and early sales it wins. See 3D printing for end-use parts.
- CNC machining — the right call when you need real tolerances, engineering material properties, or metal. Programming and setup are the fixed cost, and they are far below mold cost. Details in CNC machining for prototypes.
- Sheet metal fabrication — laser cutting and press brake forming need no part-specific tooling at all, making it unusually economical at low volume. Design rules in our sheet metal design guide.
- Hand assembly and off-the-shelf enclosures — a standard extruded or molded enclosure that you machine and label is often dramatically cheaper than any custom housing.
1,000 units: the first crossover
This is where the interesting decisions live, because several options are genuinely competitive.
- Urethane casting — a silicone mold made from a printed master. Low tooling cost, injection-molding-like surface finish, wide range of durometers and colors. Tools wear out after a limited number of pulls, which caps volume. See urethane casting.
- Aluminum bridge tooling — a real injection mold cut in aluminum instead of hardened steel. Substantially cheaper and faster to build than production steel, with a limited but useful tool life. It bridges the gap between prototype and production, which is exactly what this volume needs.
- SLS nylon production — genuinely viable at this quantity for functional parts with no tooling at all, especially complex geometry that would need side actions in a mold.
- Sheet metal with soft tooling — simple form dies and fixtures speed up repeatable bends without full press tooling.
At 1,000 units, run the comparison honestly. If your part is simple and your volume is likely to grow, aluminum tooling now is often cheaper than printing 1,000 parts and then buying tooling anyway.
10,000 units: classic tooling territory
Here dedicated tooling almost always wins, and the conversation shifts to which tool.
- Steel injection molding — the workhorse for plastic parts. Tooling is a real investment with a lead time measured in weeks, and per-part cost drops dramatically. See injection molding costs, and expect a tooling lead time measured in weeks.
- Die casting — for metal parts in aluminum or zinc, with thin walls and good detail. Covered in aluminum die casting.
- Stamping and progressive dies — for high-volume sheet metal parts, replacing laser and brake work.
- Extrusion — for constant-cross-section aluminum or plastic profiles, with die costs far below mold costs.
At this volume, design decisions carry real money. A change that shaves a fraction of a dollar per part matters, which is why disciplined design for manufacturing and value engineering pay for themselves before the first shipment.
100,000 and up: optimize the cycle, not the tool
Beyond this point tooling cost is noise. What matters is cycle time, cavity count, scrap rate, and labor content. Multi-cavity and family molds, hot runner systems, automated part removal, and in-line assembly all become worth their investment. Material cost per part becomes a leading line item, so material selection tightens and resin grade becomes a negotiated item. Sourcing strategy usually shifts too, toward established overseas partners and formal incoming quality sampling.
How to find your own crossover point
- Get quotes for two or three candidate processes at your realistic first-year volume, not your dream volume.
- Build a total-cost curve for each: tooling plus per-part times quantity, across a range of quantities.
- Add the costs that are easy to forget — secondary operations, finishing, assembly labor, scrap, and freight. Capture them in your bill of materials rather than in a per-part price alone.
- Weigh the non-cost factors: tolerance capability, material options, finish, lead time, and how fast you could change the design after launch.
- Check factory minimums. A supplier's minimum order quantity can rule out the process you picked on paper.
The most common mistake is buying production tooling before demand is proven. The second most common is printing parts for two years while a mold would have paid for itself in six months. Both come from skipping the arithmetic that the wider manufacturing technologies pillar walks through process by process.
Not sure which process fits your volume? Tell us the part, the material, and your realistic quantity through our contact form and we will model the total cost across the viable options.