There is no such thing as a price per kilogram
Buyers ask for a rate per part, or per kilogram, or per square metre of sheet. Suppliers who give one are either quoting a narrow speciality or guessing about your drawing.
What follows is the structure of the cost, line by line, and the order in which each one grows. Once you can see it, you can negotiate on the variables that actually move the number instead of asking for a discount on the total.
1. Material, and the part of it you pay for but never receive
Material is usually the largest single line, and the one buyers understand least well, because the cost is not the weight of the finished part.
You pay for the sheet that was consumed to make it, which includes the blank outline plus whatever the nesting left around it. A compact, tessellating part carries less scrap than an awkward shape with long awkward edges. This is why two parts with identical weight can differ substantially in material cost, and why a small change to the outline can matter more than a negotiation.
Grade and thickness tolerance matter too. Moving from 304 to 316 stainless, or demanding a tight thickness tolerance where standard would do, is a real increase in cost that buys a real property — or buys nothing, if nobody specified why.
2. Setup, amortised over the quantity
Every operation has a fixed cost to start: nesting and programming, a press brake setup, a fixture, a first article check. That cost is the same whether you order 1 or 1,000.
This is the entire reason unit price falls with volume, and it is arithmetic rather than a discount. A setup that takes two hours is negligible across a thousand parts and dominant across one. If a supplier offers a volume discount on a part with almost no setup, the discount came from somewhere else in the quote.
3. Machine time, driven by the route rather than the part
Machine time is charged at an hourly rate that includes the machine, the operator, the floor space and the power. The rate differs by machine, so the route you choose determines the bill.
Laser cutting is fast for flat profiles and scales with cut length, not part count. Forming is fast per bend but slow to set up. Stamping is expensive to tool and then almost free per part. Deep drawing is tooling-heavy and unforgiving of design changes. Machining is charged against the volume of material removed, not the volume of the finished component — which is why machining from solid gets expensive quickly on a part that could be formed.
4. Tooling, when the volume justifies it
Flat profiles are laser cut, because there is no tool to pay for. Once quantities are high enough, a die becomes cheaper per part than cutting, and the question becomes where the crossover sits for your part, your material and your tolerance.
Tooling is also the item that changes the risk profile. A die is a commitment that only pays back at volume, and a design change after it is cut is a tooling project rather than an edit. That is why we quote the route and the crossover rather than assuming one.
5. Labour-heavy operations, which resist automation
Welding, assembly, deburring and packing scale with handling, not with machine time, and they are where two quotes for the same part most often diverge.
They are also where the geography shows. In a region where hand work is economical, these steps are performed; in a high-labour-cost region they are designed out or automated, which changes the part rather than the price.
6. Surface finish, priced by area and by risk
Finishing is usually charged on surface area, but the cost driver is often the process rather than the area. Anodising has a minimum batch charge, powder coating has a minimum load, and plating has both plus the risk of rework if the surface preparation is wrong.
Handling matters here. A finish applied to a part that then has to be re-handled, packed and shipped without marking adds cost that does not appear on the finish line of the quote.
7. Inspection, and the documents that ship with the batch
Inspection costs money and it is not optional on anything with a tolerance. What varies is how much, and what you get for it.
A CMM report against the drawing’s nominal and tolerance, a first article inspection report on production runs, and a material certificate traceable to the heat are all work. They are also the reason a cheaper quote can be cheaper, so the comparison is only fair if both quotes include the same documents. Ask what is not included before you ask for a discount.
8. Packing, freight and duty
Packing is a real cost driver on thin, formed or finished parts, because the failure mode is transit damage rather than a bad part. Air express takes 3 to 7 days and sea freight 15 to 30 from China. Duty is set by the destination country and paid by the buyer unless the terms say otherwise.
The number to compare across suppliers is landed cost per part at your receiving door, not the unit price, and the Incoterm should be named in the quote rather than assumed.
The same part, priced at three quantities
| Cost line | At 1 piece | At 100 | At 50,000 |
| Material | Full sheet consumption, high scrap share | Nested, scrap shared | Nested and tooled for minimum scrap |
| Setup and programming | Not amortised at all | Amortised lightly | Effectively free per part |
| Process route | Laser cut and formed | Laser cut and formed | Stamping, once the die is paid for |
| Tooling | None | None, unless a fixture is needed | Die cost amortised across the run |
| Labour operations | High share of total | Moderate | Automated or jigged |
| Inspection | Full first article on one part | First article plus sampling | Sampling against a controlled process |
| What dominates | Setup and handling | Material and machine time | Material and tooling amortisation |
No rates are given here on purpose. A rate that is not tied to your drawing, material, tolerance and quantity is a number invented about a part nobody has seen.
How to use this when you negotiate
- Ask which line dominates your part. The answer tells you which lever to pull.
- If setup dominates, reduce the number of distinct operations, not the unit price.
- If material dominates, look at the outline and the nesting before you look at the margin.
- If finishing dominates, ask about minimum batch charges and whether another part can share the load.
- Ask where the process crossover sits. The cheapest route at 100 pieces is rarely the cheapest at 50,000.
The related pages go deeper on the two questions that follow: what a design-for-manufacture review catches, and why a factory can quote a single prototype.
Key facts
| Quote turnaround | 24 hours, with a process route and a tolerance per stage |
| Minimum order quantity | None |
| Processes in one building | Laser cutting, bending, stamping, deep drawing, welding, CNC machining, turning, assembly |
| Typical tolerances | Laser cutting ±0.05 mm, forming ±0.1 mm, five-axis machining ±0.005 mm where required |
| Sample lead time | 7 days typical |
| Production lead time | 20 to 30 business days after sample approval |
| Documents shipped | CMM report, first article inspection report, EN 10204 3.1 material certificate, finish readings |
| Shipping | Air express 3 to 7 days; sea freight 15 to 30 days |
Frequently asked questions
Why does the unit price fall so much with quantity?
Because setup does not scale. Programming, a machine setup, a fixture and a first article check cost the same whether you order one part or a thousand, so the same fixed amount spread across more pieces reduces the unit price. Most of the fall is arithmetic rather than a volume discount.
What is the biggest cost driver in a sheet metal part?
Material is usually the largest single line, but the driver that surprises buyers is that you pay for the sheet consumed rather than the weight of the finished part. Outline shape and nesting therefore matter more than most people expect, and a small design change can outweigh a price negotiation.
Is it cheaper to machine a part from solid or form it from sheet?
Machining is charged against the volume of material removed, so it gets expensive quickly on anything with a lot of waste. Forming from sheet avoids that, but needs a route and sometimes a die. The crossover is a real calculation rather than a rule, and it depends on the geometry and the quantity.
Should I ask a supplier for a lower unit price?
Ask which cost line dominates your part first. If setup dominates, reducing the number of distinct operations helps more than a discount. If material dominates, examine the outline and nesting. Asking for a lower number without knowing which line is driving it usually just moves the cost somewhere you cannot see.
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