Which number is being quoted
An aluminum price per pound or per ton is a starting point, not a purchase price. It is one layer of a stack, and most disagreements between a buyer and a supplier come from comparing two different layers.
| Layer | What it represents | What it excludes |
|---|---|---|
| Exchange benchmark | Global primary aluminum price per metric ton (LME) | Delivery, alloying, form, manufacturing |
| Regional premium | Physical delivery and regional supply (in North America, the Midwest Premium) | Alloy surcharge, fabrication |
| Alloy and form | Composition of the grade; ingot, billet or sheet | Melting, scrap handling, forming |
| Finished casting | Metal plus melting loss, yield, tooling, machining, finishing, inspection | Nothing: the number you pay |
Price per ton ÷ 2,204.62 = price per pound. That converts units; it does not add the premium.
What actually drives a casting's piece price
- Metal per shot. Part weight plus gates, overflows and biscuit; yield is the share that ends up in the part.
- Cycle time and machine size. Wall thickness sets solidification time; projected area sets the machine tonnage.
- Cavities. More cavities lower the piece price and raise the tool price.
- Scrap rate. Leak, X-ray and dimensional rejects are paid for by the good parts.
- Heat treatment. T6 adds furnace time and handling, and often straightening and a dimensional check.
- Machining. Number of setups, features and stock removed; often the largest single line.
- Finishing and masking. Coating, masking of sealing faces and threads.
- Inspection and testing. 100% leak testing, X-ray sampling, reports.
- Packing and freight. Protection of machined faces, carton or crate, Incoterm.
Compare two quotations line by line
Fill in from each quotation. Where a supplier did not quote a line, mark it "not included", not zero.
| Line | Quote A | Quote B | Same scope? |
|---|---|---|---|
| Alloy and standard | enter | enter | yes / no |
| Casting (per part) | enter | enter | yes / no |
| Heat treatment | enter | enter | yes / no |
| Machining | enter | enter | yes / no |
| Finishing | enter | enter | yes / no |
| Leak test and X-ray | enter | enter | yes / no |
| Tooling, life, cavities | enter | enter | yes / no |
| Samples and FAI | enter | enter | yes / no |
| Packing and Incoterm | enter | enter | yes / no |
| Metal price basis and adjustment clause | enter | enter | yes / no |
Where design changes reduce cost
- Even wall sections: shorter cycle, fewer shrinkage rejects
- Fewer slides and undercuts: lower tool cost and maintenance
- Machining only where the function needs it: cast to near shape elsewhere
- Datum targets on cast surfaces: fewer setups
- Acceptance zones instead of whole-part limits: fewer false rejects
- Masking only real sealing and contact faces
Metal price adjustment
For repeat orders, agree how the metal line follows the market: the benchmark and premium used, the reference date, the adjustment interval, and the weight it applies to (gross shot weight or net part weight). This keeps the conversion cost fixed and the metal cost transparent. For clause wording, see aluminum price adjustment clauses for casting quotes.