Top 10 Questions to Ask Before Ordering an Injection Mold

Ordering an injection mold is usually the biggest single line item in a plastic part project. Get it right, and the tool pays for itself within the first production runs. Get it wrong, and you spend the next year fighting flash, paying for retrofits, or commissioning a second mold.

We have been on the receiving end of thousands of mold inquiries, and we have repaired plenty of molds built elsewhere. The buyers who get the best outcomes all ask roughly the same set of questions up front. Here are the top 10.

1. Which Mold Steel Are You Quoting, and What Hardness?

“Steel mold” can mean unhardened P20 or 48 HRC H13. The steel grade and heat treatment determine mold life more than anything else. Ask for the exact grade and target hardness in writing — and ask what hardness is planned for sliders and lifters, not just the main cavity blocks.

2. What Is the Guaranteed Mold Life?

A serious injection molding supplier will commit to a shot warranty: 100,000, 500,000, or 1,000,000+ cycles depending on the steel class. If the answer is vague (“it will last a long time”), treat that as a warning sign. The warranty should also state what happens if the mold fails early.

3. Is This an Export Mold Built to HASCO or DME Standards?

If the mold will run in your country, it must match your machines: standard mold bases, fittings, and electrical connectors. A mold built to domestic Chinese machine standards can be useless on an American or European press. Confirm the mold base standard, fitting type, ejector pattern, and connector standard before the design starts.

4. Can I See a Mold Flow Analysis Before Steel Is Cut?

A mold flow report shows predicted fill patterns, weld line locations, air traps, and warpage risk. It takes a day to run and can save weeks of rework. If a supplier refuses to share it, they either did not run one or do not want you to see it. Neither is acceptable on a production mold.

5. What Is Included in the Mold Quote?

Some quotes cover the mold only. Others include mold design, mold flow, T1 to T3 trials, sample shipping, and texture. Ask for a line-item breakdown so you can compare quotes fairly. The cheapest number is rarely the cheapest project once you add the “extras” other shops bill separately.

6. What Is the Lead Time — to T1 Samples, Not to “Completion”?

“Six weeks” can mean six weeks to first samples or six weeks until the supplier considers the mold done. Ask specifically: when do T1 samples ship, and how many trial rounds are included? For most single-cavity molds, 3–5 weeks to T1 is realistic. Multi-cavity tools with complex actions take longer.

7. How Are Design Changes Handled During the Project?

Designs change — that is normal. What matters is the process: is there a formal change order system, who approves timing and cost impacts, and how are changes documented? Shops without a change process will either refuse reasonable changes or surprise you with a bill at the end.

8. Who Owns the Mold, and What Happens If We Move Suppliers?

You are paying for the tool, so you should own it — full stop. Get ownership in the contract, and confirm the mold can be shipped to you complete with all electrodes, spare inserts, and documentation. Ask what the mold export crate includes. A mold that arrives without its drawings or spare parts is worth far less than one that does.

9. What Payment Terms Protect Both Sides?

The industry norm for export molds is roughly 40% deposit, 40% on T1 sample approval, 20% before mold shipment. Be careful with anything demanding more than 50% upfront, and be equally careful with “100% on delivery” offers — shops that take all the risk sometimes cut corners to protect their cash flow. Milestone-based payments tied to verifiable events work best for everyone.

10. Can You Show Reference Customers in My Region?

Any established injection molding supplier should be able to point you to customers in North America or Europe who can confirm the molds arrived as promised and still run. If reference checks stall, that tells you something.

The Common Thread

Notice that none of these questions is about price. Price is the output of the answers: steel, life, standards, and scope determine cost. Buyers who negotiate only on the quote number end up paying the difference later — in trials, repairs, and delays.

Want a mold quote that answers all ten questions in writing? Contact us with your drawings, and we will respond with a detailed, line-item proposal within 24 hours.