A foundry cannot quote what it cannot see. The price of a casting is built from the weight of the part, the complexity of the pattern, the number of cores, the feeding arrangement, the machining content and the inspection regime. Each of those is derived from the drawing and the accompanying information, and where the information is missing the foundry has to guess. A guess is either cautious, which makes the price high, or optimistic, which makes the price wrong.
This is why the quality of a quotation depends more on the customer's preparation than on the foundry's pricing model. Two foundries given the same incomplete package will produce two different numbers, and neither will be the number that applies once production starts.
The list of things a foundry needs is not long, and most of it is information the customer already has. The difficulty is that it is usually spread across several documents and several people, and assembling it takes an hour that nobody schedules.
The drawing is the centre of the package. It needs to show the finished part completely, with all dimensions, tolerances and surface requirements. It needs to identify which surfaces are as cast and which are machined. It needs to state the material and the condition. And it needs to carry the porosity acceptance requirement, zoned by function, with the acceptance method named.
Beyond the geometry, the drawing needs to state the things that are easy to leave off because they are not dimensions. The parting line preference, if there is one. The draft requirement, if the customer has a view. The surfaces where a riser scar would be unacceptable. These are not demands on the foundry so much as information that prevents a wrong assumption.
A drawing that is dimensionally complete but silent on acceptance is a drawing that will produce a quotation with an assumed acceptance criterion. That assumption will be discovered at first article, and the conversation that follows will be about whose assumption was correct rather than about the part.
Volume is the single largest driver of price, and it is not enough to state an annual figure. The foundry needs to know the first order quantity, the expected annual quantity, the expected programme life and whether the demand is steady or lumpy. A programme that needs two hundred parts a year for five years is a different proposition from one that needs a thousand parts once.
The pattern cost has to be recovered somewhere, and how it is recovered depends on the demand profile. A steady programme can absorb it across many parts. A single order has to carry it in one price. The same casting can therefore have two very different prices without anything about the part changing.
It is also worth saying what happens if the volume does not materialise. A foundry that has priced on the assumption of a long run and then receives a single order has a legitimate reason to revisit the price, and a customer who disclosed the uncertainty at the start avoids a difficult conversation later.
Lead time expectations, delivery address, packaging requirements and the inspection regime all affect the price and all need to be stated. So does the standard the part must meet, if there is one, because a part quoted against a general commercial standard and then inspected against an aerospace standard is a part that will fail.
On the technical side, the foundry needs to know the service conditions: temperature, pressure, medium and loading. These determine the material selection and the acceptance criteria, and they are frequently omitted because the drawing shows the shape and says nothing about what happens to it.
There is a fifth category that is often overlooked: the history. If a similar part has been cast before, the foundry needs to know what went wrong. A previous pattern that wore, a feeding problem that was never solved, a machining allowance that proved marginal. That information is worth more than a page of specification, and it usually exists in someone's memory rather than in a document.
A complete package produces a quotation that can be relied on. It also produces a faster quotation, because the foundry is not spending its first week asking questions. And it produces a better part, because the assumptions that would otherwise have been made silently are made explicitly and can be checked.
The reverse is familiar. An incomplete package produces a low quote that rises, a schedule that slips, and a first article that reveals a disagreement about acceptance that was never really about the casting at all. None of that is inevitable, and none of it is the foundry's fault alone.
Components that are fabricated rather than cast avoid some of this, since a fabrication drawing carries its own joint and inspection requirements, as the work in the aluminium water tank range demonstrates. But the principle is the same: the more the specification says, the less the supplier has to assume.
Shanghai Fupower Industry was founded in 2009, operates from four facilities covering 53,819 sq ft and employs more than 50 people in Shanghai. That is a foundry and fabrication base large enough to take on a programme and small enough that the people quoting are the people who will run it. Giving them a complete package is the shortest route to a price that holds.
A foundry needs the drawing, the acceptance criteria, the material, the volume and the service conditions. Give it those and the quotation is a plan. Withhold them and the quotation is a guess, however carefully it is presented.
A package sent as a drawing alone produces a price for a shape rather than for a component. Sending the acceptance criteria, the volume and the service conditions with it produces a price that can be held. TIG aluminium welding enquiries benefit from the same discipline.
Expect questions about draft, about which surfaces must be sound and about whether the design is fixed. None of them are objections; they are the foundry building a number from information rather than from assumption. aluminium fuel tank range and custom parts enquiries raise the same list.
A quote is the start of a qualification route rather than the end of a purchasing exercise. The pattern, the first casting and the sectioning report all follow, and the TIG stainless steel welding and titanium fabricated components routes have their own equivalent steps.
