How is tooling priced by a custom molded plastic cases OEM?

Answer: On steel, cavity count and structure. A 718H two cavity tool runs 100,000 to 150,000 CNY with three trials; under 80,000 usually means no heat treatment.

Why is the first order priced above volume?

Answer: Preparation sits on few pieces: changeover, trial scrap and first article inspection land on the first batch.

Who pays when the drawing changes?

Answer: Whoever changed it. A structural change by the buyer carries the cost, a supplier error does not.

Can 52 days become 30?

Answer: Partly. Steel delivery and tool making barely move, but sampling can overlap preparation, saving about 10 days.

Can the first order go below 300 pieces?

Answer: It can be discussed, though the premium passes 15 percent.

Custom Molded Plastic Cases OEM: Quote, MOQ and Lead Time

Quick answer: A custom molded plastic cases OEM project is bought as four blocks, not a unit price: tooling, trials, per part conversion and secondary operations. Fix who owns the tool, who pays for a drawing change, how many trials are free, and how the 52 day schedule splits into sampling, tool making, trials and production.

How a Custom Molded Plastic Cases OEM Builds the Price
Tooling Trial and Modification Costs
Deriving MOQ From Cavity Count
Four Stage Schedule for a Tooling Project
Material Acceptance and Shipping Handover
FAQ

1. How a Custom Molded Plastic Cases OEM Builds the Price

A custom part has no list price, only a build up. Two quotes on the same 2.4 kg case can sit 30 percent apart, and the gap lives in steel grade, press tonnage and secondary hours.

Tooling is priced on steel and structure: 718H for the cavity, 128,000 CNY for two cavities. Conversion comes off a machine hour rate: 130 CNY an hour on a 400 tonne press, 95 second cycle, near 1.7 CNY per case.

Line	Unit	Delivered
Tooling	per tool	drawing, samples
Trials	per shot	sample, report
Conversion	per case	moulded case

Material is never bundled. ABS at 10.5 CNY a kilo on a 2.4 kg case is 25.2 CNY, about 60 percent of the price, and a flame retardant grade adds 4 CNY. A custom molded plastic cases OEM quote without a grade cannot be audited.

2. Tooling Trial and Modification Costs

Tool payment and tool ownership is the softest paragraph in most contracts. The buyer pays and holds title, the tool sits in the supplier's plant, collectable when the project stops.

Custom Molded Plastic Cases OEM: black case standing open on white, grey foam with four circular recesses, one metal plate latch and a folding handle

Trials are counted: three free, 3000 CNY from the fourth. Modification liability follows the change: structural changes by the buyer are paid by the buyer, wrong dimensions by the supplier.

Tool life is quoted at 300,000 shots, after which cores and ejector pins are replaced.

3. Deriving MOQ From Cavity Count

MOQ follows cavity count, not a sales decision. One cavity suits cases over 600 mm, two suit middle sizes, and four pay off only under 180 mm of height.

Cavities	Press	Cycle	Daily output	First order
1	400 t	95 s	about 750	200
2	400 t	95 s	about 1500	300
4	650 t	110 s	about 2600	500

Setup corrects the arithmetic: a six hour changeover means a first order under 300 pieces spends half its press time preparing.

4. Four Stage Schedule for a Tooling Project

The clock starts at drawing freeze. Sampling 7 days, tool making 25, trials 5, production 15, which is 52 in total.

Custom Molded Plastic Cases OEM: light grey case open on a wooden bench, black gasket line on the rim, grey foam grid inside, cable coils behind

Tool making is the long block: parting, rough machining, EDM, polishing, fitting. Steel delivery alone takes 10 days, so lead time talks with a custom molded plastic cases OEM are talks about the drawing.

Trials need room for correction: the first shot shows sink and flash, the second confirms dimensions, the third produces the first article. A proven structure fits in 5 days, a new one needs 8.

Stage	Days	Deliverable	Check
Sampling	7	prototype part	appearance and fit
Tool making	25	tool and first shot	cavity layout
Trials	5	three trial shots	12 item first article
Production	15	first 300 pieces	AQL sampling

5. Material Acceptance and Shipping Handover

Incoming material is where defects start. ABS needs two hours at 80 degrees Celsius, and above 0.1 percent moisture the surface shows silver streaks.

Acceptance runs by lot: appearance at AQL 2.5, dimensions at AQL 1.0, hardware through 48 hours of salt spray, a full case dropped 1.2 m on six faces. A tool change forces a new first article.

Shipping is counted in pallets: 12 cases on a 1200 by 800 mm pallet, stacked three high, since a fourth layer leaves a permanent set.

Conclusion

Buying from a custom molded plastic cases OEM means writing the life of a tool into clauses: tool cost, free trials, who pays for a change, first order size, days per stage. Four price lines, tool title, cavity count and four schedule blocks make quotes, assets, MOQ and dates checkable. What you select in a custom molded plastic cases OEM is the discipline to run them.

This article discusses only the container (case body) side of specifications and design intent, and does not cover any handling, loading or use of the contents.