Who Owns the Mould? Tooling Cost and Control in a China OEM Order

The first time you order a custom plastic or metal part from China, a large one-off charge appears on the quote: tooling, or the mould. Buyers tend to pay it, take delivery of the parts, and never think about the steel again — until they want to move factories and discover they cannot take the mould with them. Tooling is where a lot of quiet leverage sits in an OEM relationship. Here is how it works and what to put in writing.

Why tooling is a separate charge

An injection mould, a die-casting die, or a stamping tool is a precision steel object machined specifically for your part. It can take weeks to cut and is expensive because of the steel grade, the machining hours, and the trial-and-error to get the part right. The factory charges it separately because it is a capital item, not a per-unit cost. Once it exists, your per-piece price drops, because you are only paying for material, machine time and labour on each shot.

That structure is why unit prices from China look impossibly low on large runs and why the first order carries a bump. It also means the economics only work if you keep running volume through that tool. A mould paid for and then used for a single small order is the most expensive way to buy the part.

T1, T2 and the sample rounds you are paying for

After the tool is cut, the factory runs the first trial shots, labelled T1. You inspect T1 parts against your drawing, mark up what is wrong — short fills, flash, sink marks, dimensions out of tolerance, wrong texture — and the factory reworks the steel and runs T2. Most new tools need two or three of these rounds before parts are signed off. Build that time into your launch plan: a tool that needs T3 is normal, not a disaster, but each round is a courier cycle and a week or two.

The sign-off sample from the final round becomes your reference standard, the same role the golden sample plays in a normal order. Keep a retained, sealed set. Our sample approval guide covers how to lock that reference so a later batch cannot drift away from it.

Ownership: what “you paid for it” does and does not mean

Paying the tooling invoice does not automatically make the mould yours in a way you can enforce in China. Ownership has to be written down. A tooling agreement, or a tooling clause in your manufacturing contract, should state plainly:

• That the mould is your property from the moment payment clears, identified by a tool number and photographs
• That the factory holds it only as a bailee, for making your parts, and will not use it for anyone else
• That on your written request the factory will release the mould, in working condition, within a stated number of days, against settlement of any genuine outstanding balance
• That the factory will maintain the tool and keep a log of shots run
• Who pays for repairs from normal wear versus damage from misuse

Without those words, possession wins. The steel is bolted into a press on the factory floor, and a supplier in a dispute can simply decline to hand it over.

Mould life, and why the shot count matters

Tools are quoted with an expected life in shots — the number of moulding cycles before the tool needs a major refurbish or replacement. A cheaper tool in softer steel has a shorter life; a hardened tool costs more upfront and lasts far longer. For a product you expect to run for years, paying for the better steel is usually right. Ask for the steel grade and the rated shot life in writing, and ask the factory to log actual shots so you know where the tool sits in its life. When you are close to the rated life, plan the refurbish before parts start failing, not after.

If your annual volume is modest, a mid-life tool may outlast your product. If you are running hundreds of thousands of parts a year, tool condition is something to check at every audit.

Moving the mould to a new factory

This is where ownership on paper earns its keep. If you want to change suppliers, a mould you clearly own and have a release clause for can be uninstalled, crated and trucked to the new factory. Expect friction anyway: the outgoing factory may claim maintenance costs, and the incoming factory will want to run its own trial shots because it did not cut the tool and will not warrant parts blindly. A tool built to one factory’s machine specifications may need minor adaptation to fit another’s presses.

Practically, budget for a fresh T1 and possibly T2 at the new factory, and do not scrap the old relationship until the new one is producing signed-off parts. If the tool has been idle at the old factory for many months, agree in advance who covers storage and whether the factory can scrap an abandoned tool after a set period — many will, to clear floor space.

Practical checklist before you pay the tooling invoice

• Signed tooling agreement or clause covering ownership, bailment, release, maintenance and shot logging
• Tool number, steel grade and rated shot life stated in writing
• Photographs of the finished tool and of the cavity
• A retained, sealed sign-off sample set from the final trial round
• Clarity on whether the tooling price is a true cost or is partly amortised into unit price — if amortised, know when it is paid off

Tooling numbers vary widely by part size, complexity, cavitation and steel, so we do not publish figures. Send us the drawing and target volume and we will get you a real tooling and unit quote to compare.

Cavitation: how many parts per shot

A single-cavity tool makes one part per moulding cycle. A two- or four-cavity tool makes two or four, from the same cycle time, which cuts the machine-time cost spread across each piece. The catch is that a multi-cavity tool costs more to build and needs a larger press. For modest annual volume, single cavity is usually the right call — the cheaper tool is not the bottleneck. For high volume, a multi-cavity tool pays back quickly in lower unit cost.

You can often start with a single-cavity tool to prove demand, then commission a higher-cavitation tool once the numbers justify it. Budget that as a separate second tool, not a modification of the first — adding cavities to an existing mould is rarely practical. Ask the factory to model unit price at one, two and four cavities so you can see where the crossover sits for your volume.

Family moulds for an assembly

A family mould produces several different parts of one product in a single tool — for example the top housing, the bottom housing and a clip. It saves tooling spend and keeps the parts colour-matched because they come from one shot of one material. The limits: every part in the tool has to run in the same material and colour, a single worn or damaged cavity holds up the whole tool, and you cannot easily rebalance output if you end up needing more of one part than another.

Family tooling suits a stable kit where the part ratio never changes. If you expect to sell spares or sub-assemblies separately, or the mix will shift, separate single-part tools give you more flexibility even though they cost more up front.

Planning a custom part or a private-label product from China? DE International manages tooling agreements, factory selection, trial-shot inspection and shipping to Bangladesh. Contact us through the contact page, see the services page, the China sourcing and buying agent service, or the shop. Related: NNN agreements, custom packaging and branding, and writing a product specification sheet.