Tooling Maintenance: Who Owns and Services Your Molds

The short answer: in China, the factory that runs your molds almost always handles day-to-day tooling maintenance, but who owns the molds — and therefore who pays for repairs, storage, and end-of-life replacement — is decided entirely by your contract, not by who paid the tooling invoice. Paying for a mold does not automatically make it yours. If the agreement is silent, Chinese factories typically treat the tool as their asset.

This is a costly misunderstanding. A buyer who spends thousands on an injection mold and later discovers the factory considers it factory property has funded a tool they can't move and may have to rebuy when they switch suppliers. CN Ally helps buyers document tooling ownership and maintenance terms before the first payment goes out — fixing it afterward is far harder than writing it down up front.

The split is simple: the factory does the hands-on work (cleaning, lubrication, inspections, repairs), and you set the rules in writing. This article covers how that split works in practice — ownership models, maintenance schedules, storage, wear-out, factory transfers, and the contract clauses that tie everything together.

Who owns a mold you paid for in China?

Whoever the contract says owns it. Payment settles the cost; the contract settles title. In practice, tooling arrangements with Chinese factories fall into three models:

Model · What happens · The catch

• **Factory-owned, cost amortized**: The factory pays for the mold and recovers the cost in a higher per-unit price over an agreed volume · Markup is rarely transparent; the price may never drop afterward. Get the milestone in writing.
• **Buyer-paid, factory-held**: You pay the tooling invoice in full, but the mold stays on the factory's floor with no explicit ownership clause · The most common and most misunderstood arrangement. Without a contract, the factory may treat the mold as its own.
• **Buyer-owned with transfer rights**: You pay, the contract states you own the tool, and you can move it to another factory on notice · Needs a written agreement under Chinese law — plus physical identification of the tool as your property.

A mold quote that looks complete — cavity count, steel grade, sampling rounds, price — says nothing about custody, transfer rights, or maintenance unless those terms are written down. Many factories take your tooling payment while assuming the mold stays theirs. The only fix is an agreement stating ownership transfers to you on full payment.

One more distinction that matters: the mold and the design of the mold are two different assets. A good agreement separates them — you should own the tool design files (native CAD plus a neutral format like STEP or IGES) independently of where the physical tool sits. Requesting editable source files after a relationship has broken down is, as China manufacturing lawyers put it, a common and expensive mistake.

Who handles day-to-day maintenance: you or the factory?

The factory. Routine tooling maintenance — cleaning after each run, lubrication, checking parting lines and ejector systems, minor repairs — is done by whoever runs the mold, and the tool sits in China, not in your office.

What you control is the standard. Left to themselves, many factories are reactive: fix the tool when it breaks. That costs you in degraded part quality, unplanned downtime, and tools that die long before their rated life. The contract turns the factory's default into an obligation: preventive schedules tied to shot counts, cleaning and oiling after each run, annual condition photographs, and your right to inspect the tool.

Standard agreements place the duty on the factory — maintain all tooling in good working condition, with liability for damage beyond ordinary wear. The distinction matters: ordinary wear is expected and priced in; damage from abuse (excessive clamping pressure, closing the mold on a trapped part, running dry) is a different category. The agreement should say who pays for each.

What should a proper mold maintenance schedule include?

A real program works in levels, each triggered by shot count or calendar time, whichever comes first. One widely referenced industry program sets four tiers:

Level · Trigger · What happens

• **Preventative**: Every day of production, and every time the mold goes into or comes out of the press · Wipe parting surfaces, core, and cavity with mild solvent and clean cloths; remove gas and grease buildup; check that bolts and plates are tight
• **Inspection**: Every 20,000 cycles (roughly every 10 days of steady production) · Deeper visual check of wear areas: parting lines, ejector pins, cooling channels, slides, lifters
• **Maintenance**: Every 100,000 cycles (roughly every 10 production runs) · Partial disassembly, cleaning of water lines, replacement of worn standard components, re-lubrication
• **Major maintenance**: Every 250,000 cycles (roughly half the anticipated tool life) · Full teardown, measurement of critical dimensions, resurfacing or replacement of worn inserts

These numbers are starting points. One molder profiled by Plastics Technology inspects tools after roughly 50,000 shots, then adjusts: little wear means a longer interval; early wear means a shorter one. Find the point where a tool starts degrading — flash, dimensional drift, surface marks — and service it before it gets there.

Aluminum tools run a tighter routine: disassemble and clean thoroughly after every run and before storage, checking for wear and galling each time the mold leaves the press. Disciplined maintenance can push an aluminum mold past a million shots — but aluminum forgives neglect less than tool steel.

Two things separate serious programs from paper ones: tie maintenance to actual shot data (a cycle counter on the tool is the honest way), and log every service event — what was done, replaced, and found. When a dimension drifts months later, the log says whether it's the mold, the settings, or the material. Without records, you're arguing opinions.

How should molds be stored between production runs?

Between orders, your mold sits idle — sometimes for months. Rust is the main enemy, and prevention is straightforward:

• Cool the tool to room temperature first. A hot mold in a cooler storage room collects condensation, which becomes rust on precision steel.
• Drain and blow out all water lines. Standing water rusts cooling channels from the inside, where you can't see it until performance degrades.
• Clean, then coat. Remove resin residue from parting surfaces, core, and cavity, then spray with a light rust-preventive lubricant before closing the mold.
• Use a climate-controlled space. Seal the storage area from outside humidity, dust, and corrosive vapors. Uncontrolled humidity alone can corrode tool steel over months.
• Store the last-shot sample with the mold. A bagged part from the final run is your reference for what the tool was producing when it went into storage.

Settle the commercial side in writing too: who pays for storage, and for how long. Some factories store tools free; others charge monthly warehousing after a grace period. And some quietly run your mold for other customers while it's idle. Prohibit that in the contract — a clause that's cheap to add and expensive to live without.

Storage conditions are one of the things factories promise in emails and skip in practice. An on-site factory audit that photographs your tool with its identification plate is the fastest way to check the reality against the contract.

What happens when a mold wears out or gets damaged?

Every mold has a rated life in shots; the achieved life depends on steel grade, part geometry, material, cycle discipline, and maintenance. A well-maintained steel mold runs hundreds of thousands of shots; an abused one can be dimensionally dead at a fraction of that. Treat the tool as a long-life consumable, not a permanent asset.

Three things need settling in advance:

Who pays for repairs during production. Minor maintenance is the factory's cost of doing business, folded into the unit price. Major repairs — a cracked cavity insert, a damaged leader pin set — need a rule: ordinary wear or factory abuse? Define the boundary and the cost split before anyone has a bill to argue about.

Who pays when the tool reaches end of life. If the expected lifetime in shots is written into the agreement, the conversation is simple: the tool delivered its rated life, and replacement is a new purchase. Without that number, you'll negotiate with a factory that insists the tool is fine.

What "worn out" means. Agree in advance on acceptable dimensional and surface drift as the tool ages. Periodic quality-control inspections during production create the paper trail that makes the end-of-life call objective.

Watch for inflated "repair fees" that are really renegotiation leverage — quotes meant to push you toward a new mold from the same factory. Annual condition photos and maintenance logs make that game much harder to play.

Can you move your molds to another factory?

Physically, usually yes — if your contract allows it. Practically, a transfer is a project, not a shipment:

• The contractual right. A transfer clause should state the factory releases the mold to you or your designated logistics provider on notice (30 days is common), once outstanding invoices are settled. Without it, the tool can be held against unrelated balances.
• Identifiable as yours. Permanent plates or tags with your company name and a unique ID, plus photographs, make it hard for a factory to claim confusion about ownership.
• The documentation. The new factory needs the full design file set, material specs, process parameters, and maintenance history. Jigs, fixtures, and test equipment often sit outside the tooling clause entirely — itemize everything, or the new factory will be missing pieces.
• Re-qualification budget. A mold is matched to a specific machine and cooling setup. Moving it means trial shots, dimensional verification, and a fresh first-article approval. Don't expect production-ready parts from the first run.

Some buyers pull their tooling out between productions and store it with a trusted third party, returning it for the next run. When that's the routine, there's no drama when you pull it out for the last time — and no idle window for unauthorized production.

What should your tooling contract actually say?

Everything above fails without one document: a tooling agreement (standalone or part of the manufacturing agreement) drafted under Chinese law, in Chinese, with a named Chinese court and a stated penalty for breach. A Western-style NDA or an English-only purchase order is close to ornamental in a Chinese dispute.

The clauses that matter most:

1. Tool definition. Define "tooling" broadly — molds, dies, jigs, fixtures, gauges, templates, test equipment, CAD files, drawings, specifications. List each physical tool in a schedule with photographs, identifying numbers, and location.
2. Ownership transfer. State explicitly that ownership passes to you on full payment of the tooling charge. The factory holds the tool as custodian, not owner. Storage, maintenance, and use create no ownership rights.
3. Tool specifications. Cavity count, steel grade, expected lifetime in shots, surface finish standard — the numbers that anchor every future maintenance and replacement conversation.
4. Sample approval gate. Release the tooling payment only after you receive and approve first-trial (T1) samples — not on order placement.
5. Maintenance and storage. Preventive schedule by shot count, cleaning and oiling after each run, annual condition photographs, your right to inspect the tool at reasonable intervals.
6. Unauthorized use prohibition. The factory may not produce parts for other parties on your tool, or move the tool to another facility without your written approval.
7. Transfer and release. The factory releases the physical mold to you or your designee on 30 days' notice against cleared invoices — no holding the tool against unrelated disputes.
8. Design files and IP. You own the native CAD files, drawings, specifications, and any improvements. The factory delivers current editable source files plus neutral formats (STEP or IGES).
9. Damage and end-of-life rules. Who pays for repairs (ordinary wear vs. abuse), how end of life is determined, and who pays for replacement.
10. Governing law and penalties. Chinese law, a named Chinese court, and a stated contractual penalty — which lets a Chinese court act without you first proving quantified damages.

You don't need a lawyer for the business logic; you need one for the document. Never wire the tooling deposit first and sort out paperwork later — by then, the leverage has already changed hands.

Tooling maintenance and ownership: FAQ

If I paid for the mold in full, is it legally mine?

Only if a written agreement says so. Payment settles cost; ownership is decided by contract. Without an explicit ownership clause, a factory will typically treat a mold on its floor as its own asset, regardless of who funded it.

Who pays for mold repairs during production?

Routine preventive maintenance is normally the factory's responsibility, folded into the unit price. Larger repairs depend on the cause: ordinary wear is usually the factory's cost, while major rebuilds and end-of-life replacement need a pre-agreed rule in your tooling agreement. Without one, expect repair bills at whatever price the factory names.

How often do injection molds need servicing?

Industry programs typically define four levels: daily preventative care (cleaning parting surfaces, checking fittings), inspection roughly every 20,000 shots, maintenance roughly every 100,000 shots, and major maintenance roughly every 250,000 shots or half the anticipated tool life. Tune the intervals to your tool, material, and volume — and tie them to shot-count data, not guesswork.

How long do injection molds last?

Mold life is rated in shots, and the achieved number depends on steel grade, part geometry, resin, cycle discipline, and maintenance quality. Well-maintained steel molds routinely run into the hundreds of thousands of shots; properly maintained aluminum molds can exceed a million in many applications. Write the expected lifetime into your tooling agreement so end of life is a measurement, not an argument.

What if the factory refuses to release my mold?

This is what the transfer clause exists to prevent. If the contract gives you the right to remove the tool on 30 days' notice against cleared invoices, a refusal is a breach with a contractual penalty — enforceable in the named Chinese court. Without a clause, your options are expensive negotiation or a new mold. Identification plates and photos strengthen your position either way.

Your pre-deposit tooling checklist

Don't wire tooling money until you can answer yes to every question:

1. Does a written agreement — governed by Chinese law, in Chinese — state that I own the mold on full payment?
2. Can I move the tool to another factory on 30 days' notice, against cleared invoices only?
3. Does the contract define tooling broadly enough to cover molds, jigs, fixtures, gauges, and design files — all listed with IDs and photos?
4. Is there a preventive maintenance schedule tied to shot counts, with cleaning and oiling after each run and annual condition photos?
5. Do I receive the native CAD files and STEP/IGES exports as a deliverable, not as a favor?
6. Does the agreement prohibit the factory from running my tool for other customers or moving it without my written approval?
7. Is the expected tool life written down in shots, with a rule for who pays when it's reached?
8. Is the final tooling payment gated on my approval of physical T1 samples?

Eight yeses and your tooling investment is protected by paper, not by trust. Trust is valuable in China sourcing — it just isn't a legal instrument.

If you're placing your first molds in China or inheriting tooling at an existing supplier, verify ownership, storage conditions, and maintenance logs with an independent check before the relationship is tested. If anything here raised a question about your current arrangement, write to hi@cnally.com or reach out through our contact page — and we'll tell you honestly whether your tooling paperwork holds up.