Why can't a Protective Case Customization Process cavity just be item plus 5 mm?

Answer: Five millimetres lets the item in but leaves no cushioning. Fifteen per face plus 1.5 mm clearance is usable; thin items go to 10 mm, but the drop test repeats.

Is a thicker wall always safer?

Answer: No. Each millimetre adds 0.85 kg, moves tonnage up a class, adds 8 seconds of cooling and over 10 CNY per unit.

How dense should ribs be?

Answer: Pitch 60 to 80 mm at 0.6 × wall. Denser produces sink and weld lines that lower rim flatness.

Answer: One per 300 mm of rim. A 60-litre case needs four; two suit cases under 20 litres.

When does a two-cavity mold pay back?

Answer: Above 3000 units a year, with break-even near 4000.

Why does one spec revision take 25 days?

Answer: A cavity recut runs milling, EDM and polishing for 18 to 20 days plus two trial rounds at 7 days.

Protective Case Customization Process: What Each Spec Step Costs

Quick answer: Dimensions in a Protective Case Customization Process are derived from payload and stacking, not chosen by eye. Every extra millimetre multiplies into mold cost, unit weight and rework days.

Specs Come Down from Load
The Internal Cavity Chain
Wall Thickness and Ribs
Structural Parts and Their Load Share
What One Wrong Spec Step Costs
FAQ

1. Specs Come Down from Load

A Protective Case Customization Process starts with three numbers, not with shape: payload per case, stacking tiers, and whether pallets double up in transit. Those fix lid load, which fixes wall thickness and press tonnage.

Spec item	Driven by	Cost of one step off
Cavity size	Outline, foam, clearance	5 mm short, 28,000 CNY recut
Wall	Stack height, case weight	1 mm thin, lid sags 3 mm
Ribs	0.6 × wall and span	Sink at root, rim past 0.5 mm
Latch count	Rim perimeter, pressure	One short, pressure lost in 3 minutes
Hinge pin	Lid weight, cycles	Play past limit at 2000 cycles

Wall from 3.5 to 2.5 mm saves 0.7 kg, about 8.4 CNY per kilo, but stacking drops to two tiers and space doubles.

2. The Internal Cavity Chain

The chain only adds, but every addition needs a written basis; skip one and the trial mold runs again.

Protective Case Customization Process: blue case open at an angle, lid raised, empty bare interior, latches and handle along the lid edge

Step	Calculation	Result (mm)
Item outline	Largest of three axes	480 × 320 × 180
Foam	15 per face	510 × 350 × 210
Clearance	1.5 per side	513 × 353 × 213
Wall	3.5 per side	520 × 360 × 220
Corners	R8 at four corners	497 × 337

The last row gets forgotten: a 513 mm cavity leaves 497 mm of flat once R8 corners are cut, and a square item jams in all four. Write tolerance as +1.5/−0, since ±1.5 reads as total and the cavity comes out 3 mm small.

3. Wall Thickness and Ribs

In a Protective Case Customization Process build at 26 kg per case and four tiers, the bottom lid carries 78 kg, plus a 1.2 eccentricity factor, so the design load is 94 kg.

Wall	Unit weight	Stacking	Lid point load
2.5 mm	3.9 kg	2 tiers	45 kg
3.5 mm	4.6 kg	4 tiers	78 kg
4.5 mm	5.4 kg	6 tiers	110 kg

Ribs do not improve with density: 0.6 × wall, so 2.1 mm beside 3.5 mm, at 60 to 80 mm pitch. Thicker sinks at the root, wider lets the lid creep at 60°C, and above 0.12 m² of projected area a 3.5 mm wall needs 800 tonnes.

4. Structural Parts and Their Load Share

In a Protective Case Customization Process, structural parts are cut first in a cost review and cost most to redo.

Protective Case Customization Process: closed blue case standing against a pale wall, arched handle and two latches on top, four short feet below

Hinge: 5 mm pin, 1.5 × lid weight per side
Latch: 320 N static holding force, one per 300 mm of rim
Handle: 60 kg rated, tested at 120 kg
Valve: 8 mm bore, under 2 kPa drop in 10 minutes

The handle is underrated. A 26 kg case lifted one-handed puts 1.8 × the static load into its root, and a root under 6 mm cracks. For 60 kg the mount needs 8 mm and two ribs, an insert worth 4000 CNY. Latch count follows perimeter: 1.5 m of rim takes four, since saving 12 CNY on one invites an 800 CNY leak repair.

5. What One Wrong Spec Step Costs

Error	Rework	Cost	Lead time
Cavity 5 mm short	Recut cavity	28,000 CNY	25 days
Wall 1 mm thin	Resin and mold change	6000 CNY	12 days
Latch hole 2 mm off	Rework insert	1800 CNY	5 days

Beyond the invoice, a 25-day cavity recut idles the line, shifts dates and forces new samples, so hidden cost runs at 1.5 × the invoice. The cheapest step in any Protective Case Customization Process is drawing sign-off, where three people read the chain and sign for two orders less than a mold change after trial. Some money should be spent: a two-cavity mold costs 40% more, 39,000 against 28,000 CNY, takes 12% off unit cost and returns within four months past 3000 units. What never pays is a cosmetic groove cut into a hinge boss, which shortens fatigue life by a third. Divide the premium by unit saving, check three-year volume, and the decision stops being taste.

Conclusion

The spec account turns payload, stacking and rim length into millimetres and yuan. A wall set by 78 kg of lid load, parts split by 320 N and 60 kg, and a rework table that explains four-digit figures. Unit price is set not by one millimetre of wall but by whether three people read the chain before signing, and that lever is the one a Protective Case Customization Process truly controls.

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.