Can gun case production fix the outline first?

Answer: It can, at a price. Outline-first usually means a small cavity or a thin buffer, and a tool change starts near 30000 CNY.

Does 10 mm really beat 8 mm in a drop?

Answer: Only partly. At 8 mm the corner already survives 1.2 m, and the extra 2 mm buys puncture resistance paid for in weight and cycle time.

Can gun case production size latches by count alone?

Answer: No. Size by span. A 900 to 1200 mm case can pass the leak test on three latches at 400 mm, if the hinge side is stiff enough.

Can insert thickness be traded against foam density?

Answer: With arithmetic. Dropping from 45 to 38 kg per cubic metre needs about 20% more thickness, so weight rises and the saving goes.

Gun Case Production Specs That Cost 46 CNY Per Rework

Quick answer: Gun Case Production specs run backwards from the load: the cavity comes from the longest item plus buffer, the wall from drop height and stack weight. Each extra millimetre of wall costs about 11 CNY per unit; one rework costs 46 CNY.

Starting from the load, not the outline
What 6 mm and 10 mm walls really cost
Ribs, lid lip and draft angle
Latch count and hinge span
Seal groove and insert fit
FAQ

1. Starting from the load, not the outline

Gun Case Production specs start with the load case, not the silhouette. An item 1130 mm long and 4.2 kg takes a 3 g longitudinal shock in transit, concentrated at both ends. So the cavity runs 1180 mm with 25 mm of buffer each side, width adds 40 mm, depth adds 30 mm; fix those three numbers and the outline is locked.

Item	Derivation	Value
Cavity length	Longest item plus 25 mm each side	1180 mm
Cavity width	Widest point plus 40 mm	320 mm
Cavity depth	Highest point plus 30 mm	145 mm
Wall	1.2 m corner drop	8 mm
Latches	One pair per 380 mm	4

Buffer is the first line cut in a cost review. Trim 25 mm to 12 mm and the case shortens by 26 mm, but the insert thins with it and the shock lands on the item ends. A rework means stripping the insert, fitting a seal and repeating the leak test: 18 minutes, 46 CNY.

2. What 6 mm and 10 mm walls really cost

Wall thickness is the costliest number in gun case production; it moves weight, cycle time and tooling together.

Gun Case Production: olive green long case flat in a moving pickup bed, two black straps crossed over the lid, ribbed floor underneath

A 6 mm shell saves 22 CNY a unit, but in the 1.2 m corner drop the wall bulges before it cracks at a rib root. A 10 mm shell costs 22 CNY more, takes weight from 4.6 kg to 5.4 kg, and stretches the rotomould cycle from 22 to 28 minutes.

For vehicle duty, 8 mm is the turning point: no corner crack at 1.2 m, and 1.2 mm of residual set after 24 hours under 180 kg.

Never put one thickness on a drawing. Rotomoulded walls run thick at corners and thin on flats, so list eight measuring points, the lowest not under 90% of nominal.

3. Ribs, lid lip and draft angle

Ribs set stiffness and tooling cost. Gun case production geometry puts rib height at 3 times wall, so 24 mm, width at 6 mm, root radius 0.5 mm. Past 120 mm of spacing the wall drums under vacuum.

The lid lip is the sealing datum: 12 mm deep, 10 mm wide, meeting a tongue in a labyrinth fit. Flatness beyond 0.3 mm keeps the gasket from seating and the leak test fails. It adds about 8000 CNY to the tool, and skipping it doubles rework.

Draft is 1.5 degrees, corner radii 25 mm or more. At 0.8 degrees the wall scuffs on ejection.

4. Latch count and hinge span

Latch count in gun case production follows span:

Up to 600 mm, two latches, span 300 mm or less.
600 to 900 mm, three, the middle one under the handle.
900 to 1200 mm, four in symmetric pairs, span 380 mm.
Past 1200 mm, one more per 300 mm; hinge span within 1.2 times latch span.

With over 380 mm between latches and no mid support, pressure lifts the middle of the gasket and the leak curve steps.

The hinge side counts too: a 6 mm pin at 460 mm span, 8 mm at 600 mm, or the bores ovalise and the lid rocks.

5. Seal groove and insert fit

Gun case production grooves and inserts are drawn together. Width is gasket diameter minus 0.8 mm, depth 78% of diameter, which puts compression at 25 to 30%.

Gun Case Production: black case interior close-up, dark foam cut to a rifle shape, seal groove along the rim, one latch hook half open

Fit item	Size	Tolerance
Gasket diameter	7 mm	0.2 mm
Groove width	6.2 mm	0.15 mm
Groove depth	5.5 mm	0.15 mm
Insert thickness	25 mm	1 mm
Insert to wall gap	1.5 mm	0.5 mm

Add 3 mm of foam and the lid presses harder: compression rises from 28% to 33%, tighter at first, then permanent set and a leak at year two.

Conclusion

Gun Case Production spec work is a one-way chain: load, cavity, outline, wall, weight, cycle time. Each link converts to money, about 11 CNY per millimetre of wall and 46 CNY per rework. Getting the chain right in gun case production beats arguing over a quotation.

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.