Why is the lid liner a 12/25 mm two-layer stack?

Answer: The 12 mm top locates with little rebound, the 25 mm lower leaves compression travel. The Custom Military Protective Case numbers them apart and strikes any grade whose rebound exceeds the register.

How is ≤0.5 mm mould mismatch measured?

Answer: One point is taken on each of the four mouth sides, the lateral step between lid and body rabbets gauged, and the largest value kept. Four points are logged over 3 trial runs.

Why read ±1.5 mm cavity tolerance with the case fastened?

Answer: A lid-up clear size runs large and does not match the delivery drawing. The Custom Military Protective Case remeasures with latches closed and the gasket at 23%, logging assembly sink so the figure compares with trial readings.

How is a 200-unit minimum lot released?

Answer: Every shell is measured for mismatch, cavity length-width and liner rebound on one line; a missing figure drops the lot.

Custom Military Protective Case

Quick answer: A Custom Military Protective Case pairs a 12/25 mm lid-liner stack with ≤0.5 mm mould mismatch, holding ±1.5 mm cavity tolerance after 3 trial runs.

Lid-liner layer thickness in a Custom Military Protective Case
Mould mismatch at the case mouth
Tolerance readings across trial moulding runs
Cavity fit checked at assembly
Mismatch release line for custom batches
FAQ

1. Lid-liner layer thickness in a Custom Military Protective Case

The divide between a custom job and a catalogue box is the tolerance chain: change the lid layering and the mould mismatch carries the clear cavity size away with it. This Custom Military Protective Case measures 640×460×270 mm outside, 570×395×200 mm inside, with a 4.7 mm wall, and the lid liner is a 12/25 mm two-layer stack rather than one loose foam block. The 12 mm top layer handles location, the 25 mm lower layer takes the load; shift either thickness and the datum face moves when the lid closes.

Layer thickness has to sit on grades that can be measured and retested. The 12 mm layer rebounds little, so it holds the datum face on the drawing; the 25 mm layer leaves travel to keep that face from being pushed crooked at closure. On the Custom Military Protective Case the two layers are numbered on the sample board, and rebound is logged each trial run.

The moulding shop measures layering, not total thickness. When the mould halves close, lid cavity depth is set by the tool and the liner is fitted later. If the stack rides the upper tolerance, the liner meets the case mouth before the mould faces touch and holds them apart; at the lower tolerance a gap remains and steals compression from the gasket. The Custom Military Protective Case logs both extremes: three cavities per run are measured from the lid datum to the liner face, and a spread beyond the register sends the tool back. Layering and the mould face are two links on one chain. Nominal thickness on the board and clear size on the bench differ by the stack-up.

Layer grade	Lid datum drift	Verdict
10/22 mm	0.9 mm	Reject
12/25 mm	0.3 mm	Threshold
14/28 mm	0.7 mm	Reject

2. Mould mismatch at the case mouth

Mould mismatch is the step where the halves fail to line up at the parting plane, read as lid-to-body rabbet offset. The Custom Military Protective Case holds this step to ≤0.5 mm: beyond that figure the two liner datums shift against the body and the drawing's cavity length and width stop being delivered.

Custom Military Protective Case olive green open on a steel trolley, dark foam slot array in the lid, divided base foam, shelves behind

The step clusters near latch and hinge seats. Inspection takes one point on each of the four sides, gauges the rabbet step with a feeler or a coordinate machine, and records the largest value. Across 3 trial runs the Custom Military Protective Case logs all four points; whichever side nears 0.5 mm first has its insert adjusted rather than adding material all around. IP67 enters the report as a benchmark method, not a rating already obtained.

3. Tolerance readings across trial moulding runs

Trial moulding runs 3 rounds, each sampling the same batch of cavities to see whether the ±1.5 mm cavity tolerance is delivered. Round one reads raw deviation, round two folds in rebound, round three remeasures assembled. The Custom Military Protective Case does not treat one passing point as release, but reads how a single cavity moves across rounds.

Trial round	Cavity length-width deviation	Mould mismatch
Round 1	+1.2 mm	0.42 mm
Round 2	+1.4 mm	0.47 mm
Round 3	+1.5 mm	0.49 mm

All three rounds hug the upper edge of ±1.5 mm, with barely 0.1 mm of margin. This row is written into the delivery drawing and later batches are signed against it.

Clear size is measured with the lid closed and latches fastened, not lid-up. Each round on the Custom Military Protective Case separates the 7.4 kg empty and 18 kg loaded states: under load the mouth opens slightly and the mismatch reads higher, so signing only the empty state lets assembly throw up an out-of-tolerance part. A remeasure after 3700 cycles checks that hinge and latch wear has not pried the tolerance open.

4. Cavity fit checked at assembly

Assembly recheck moves the shell from the bench to the real fastened state: the 4 latches at 445 N each are closed in turn, the 2 gaskets brought to 23% compression, and the fit between cavity and lid liner measured. The Custom Military Protective Case uses this step to confirm the drawing's clear size was not reached with the lid open.

Custom Military Protective Case olive green closed shell in side close view, two front latches, recessed handle, vertical ribs and rounded corners

Fit is read at the relief pockets, lid datum contact and post-fastening warp. At 23% gasket compression the lid settles slightly; if the stack rides high, that settlement pushes the pockets into the cavity and eats part of the tolerance. The Custom Military Protective Case measures clear size before and after fastening, logs the difference as assembly sink, and drops back to a thinner layer grade if the sink exceeds its register.

5. Mismatch release line for custom batches

Batch release turns on mismatch. A custom lot with a 200-unit minimum runs on one tool, and every cavity is checked at the four mouth points. The Custom Military Protective Case sets its release line at 0.5 mm, and a cavity past that line is not repaired back into the pass count.

The mismatch release line is fixed at 0.5 mm; cavities in the trial sample that cross it are marked separately and kept out of the drawing datum.

Mismatch reading	Cavity tolerance delivered	Disposition
0.35 mm	inside ±1.5 mm	Release
0.50 mm	±1.5 mm boundary	Release line
0.62 mm	beyond ±1.5 mm	Mark separately

JUNZHIJIA centres custom lots on 0.50 mm. In a 200-unit minimum every shell is measured for mismatch, cavity length-width and liner rebound, and the three figures share one inspection line. A missing figure drops the lot from the pass count.

Conclusion

Tolerance delivery on a Custom Military Protective Case rests on lid-liner thickness and mouth mould mismatch. The 12/25 mm stack, ≤0.5 mm mismatch, 3 trial rounds and ±1.5 mm cavity tolerance must be read on one batch, or comparison is lost. Measure rebound, run the three trial readings, then recheck the fastened assembly; reversing it records assembly sink as tool error.