Can one foam cutting layout serve several kinds of kit?

Answer: Within a family, yes. Across sectors, no: weapons need grip, instruments depth control, tools clearance.

How deep should a pocket be cut?

Answer: Part height plus 2 mm, minus compression: 1 mm for hard shells, 3 mm for soft goods.

Does higher density protect better?

Answer: Not automatically. Dense foam grips harder and polishes at the mouth; 55 kg/m³ suits heavy kit.

Can a pluck grid replace a cut pocket?

Answer: For small batches of regular parts. The torn edge frays after 200 insertions, so precision gear wants a cut pocket.

Does insert colour matter in use?

Answer: For inventory. Dark foam hides dirt but also a missing item; pale foam shows an empty pocket.

Foam Cutting Applications: Five Configurations by Scenario

Quick answer: Foam cutting lands mostly in case inserts, in five shapes: a solid block cut for one part, layers stacked to different depths, a pluck grid, local blocks, and multi-pocket layouts. The scenario fixes shape, density and thickness.

Where Foam Cutting Lands: Five Pocket Shapes
Weapons and Instruments: Solid Cut and Interference
Test Gear: Layered Depth and Cable Channels
Film, Drones and Panels: Multi-Pocket Layouts
Medical and Emergency: Wipeable, Cold and Colour
FAQ

1. Where Foam Cutting Lands: Five Pocket Shapes

Nine in ten foam cutting jobs end as a case insert, yet pocket shapes differ sharply. Weapons need one solid block that grips the outline, instruments need three depths, tools need a grid of squares, film gear needs a dozen pockets in one box.

Shape follows the part, never the process. Count pieces, measure the largest outline and the thinnest section, then pick density and thickness.

Scenario	Pocket shape	Foam and density	Thickness
Weapons	Solid block, interference	EVA 55 kg/m³	75 mm, three layers
Test gear	Stacked, three depths	EVA 45 or PE 38	22 to 55 mm
Film gear	8 to 12 pockets	EVA 45 plus convoluted	30 to 60 mm
Comms panels	Flat sheet, corner blocks	PE 30	25 mm
Tool sets	Squares, 2 mm gap	EVA 45 or EPE 30	20 to 40 mm

2. Weapons and Instruments: Solid Cut and Interference

In foam cutting, a long hard part sits in EVA at 55 kg/m³, cut 1.5 mm under its outline. Below 45 kg/m³ the same interference loosens in summer heat, and every reload needs a fresh shove.

Foam Cutting: a grey case open on white, base cut with two long channels and two square pockets, flat black foam in the lid

Layers run 20, 30 and 25 mm: base, cradle, convoluted lid foam, 75 mm total. Against 90 mm of internal height that leaves 15 mm of preload; under 10 mm the part still travels.

Failure starts at the mouth: after 500 insertions the edge collapses 0.8 mm and half the grip goes, so the mouth keeps 3 mm of straight wall.

3. Test Gear: Layered Depth and Cable Channels

An instrument arrives with probes, a supply and cables, so pockets run at 55, 38 and 22 mm, built from a 20 mm base sheet with blocks bonded on top.

Foam cutting leaves cable channels 12 mm wide and 15 mm deep, with a bend radius of at least 25 mm. Tighter puts a hard kink in the cable, and the core breaks after about three months.

Instrument foam is compressed 12 to 18 percent. Under 12 it does not carry the mass; over 18 the panel must be forced in and calibration drifts.

4. Film, Drones and Panels: Multi-Pocket Layouts

Film cases carry 8 to 12 pockets: body, lenses, batteries, cage. Lenses stand upright with 2 mm radial clearance; lying flat loads the barrel.

Foam Cutting: a grey case open on a workbench, six square pockets cut in the base, three convoluted foam blocks stacked beside

A drone takes six pockets with 12 mm ribs, each arm cut 2 mm over its folded size. Ribs under 8 mm tear during cutting, and a torn block is scrap.

Comms panels use a 25 mm sheet with four corner blocks, saving 40 percent of material, at the cost of 1 to 2 mm of slide.

5. Medical and Emergency: Wipeable, Cold and Colour

Medical foam cutting must be wipeable: closed-cell EVA or PE, cleaned with 70 percent alcohol 50 times. Open-cell foam absorbs the spill, and one leak makes the pocket permanently dirty.

Emergency stock is judged cold: 48 hours at -25 °C, then out, and no cracking. Standard EPE stiffens at that temperature and splits along the mouth on the first drop, so low-temperature EVA is specified.

Scenario	Failure mode	Countermeasure	Check
Medical	Cannot be cleaned	Closed-cell EVA, 50 wipes	Colour after wiping
Emergency	Cold cracking	Low-temp EVA, 48 h at -25 °C	Drop after removal
Tools	Oily spanner will not fit	2 mm gap per pocket	Invert when loaded
Film gear	Barrel under load	Lens upright, 2 mm radial	72 hours loaded

Tool sets are divided by piece count with a 2 mm gap; below 1 mm an oily spanner will not enter and the user levers it, which lifts the wall. Colour follows use: dark grey hides marks, pale foam shows a missing tool.

Conclusion

Weapons want grip, instruments depth, film gear upright lenses, drones ribs, medical kits a surface that survives wiping and cold. Get the shape wrong and density cannot rescue it; applications are decided inside each case, by the parts and how they lift out.

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.