How is a tool carrier rated load set?

A: By the weakest path: hand carry on handle-root breaking force at four times static, shoulder carry on the ears at 1.8 times load.

How much clearance should a compartment have?

A: 4 to 6 mm per side; tighter blocks a gloved hand, looser rattles.

Can shell and textile specifications share one drawing?

A: Yes, in separate columns and units.

Which tolerance items need full inspection?

A: Diagonal difference and seam gap, which decide whether the unit sits flat.

What goes wrong when hardware is specified "as per sample"?

A: The sample wears and is lost, leaving no shared reference. State material, plating, spring thickness and cycle life.

Tool Carrier Specifications: Size, Shell and Load Paths

Quick answer: Tool carrier specifications are worked back from the load list, not picked from a catalogue. Measure the largest envelope and the heaviest item, set the cavity, let the carrying method fix the ratio and handle position, then write walls, weights and tolerances as numbers so two factories build the same unit.

Tool carrier specifications: working back from the load list
Rounding rules for envelope and compartment size
Writing shell and textile specifications
Load distribution and mounting points
Hardware selection and the tolerance table
FAQ

1. Tool carrier specifications: working back from the load list

Lay out one shift's tools, measure the largest in three axes, weigh the heaviest, count pieces per station. Those three numbers start the cavity; skip them and it ends up long but shallow.

Design input	How to measure	What it fixes	Example
Largest envelope	Callipers, three axes	Net length and depth	240 mm net, 65 mm deep
Pieces per shift	Count per station	Compartments and tiers	Twelve, one tier
Heaviest item	Scale, average of three	Base thickness	2.5 mm
Carrying method	Distance and steps	Handle type, ratio	Hand carry, 2.2 to 1

2. Rounding rules for envelope and compartment size

Envelope sizes round to what can be carried. Hand-carry bodies run 400 to 520 mm long, 300 to 360 mm wide, under 220 mm high; above that the base catches the calf and the user lifts with two hands.

Tool carrier in sky blue lying closed, integral moulded handle at front centre flanked by two latches, corner ribs and debossed lid panel

Compartment maths is finer. Net size is the envelope plus 4 to 6 mm per side: under 4 mm a gloved hand cannot extract the tool, over 6 mm it rattles. Divider thickness counts separately, 2.0 mm for moulded ribs and 12 mm for foam, and mixed dividers force the net length to be recalculated.

3. Writing shell and textile specifications

Shell and textile are two languages on one drawing, so they sit in separate columns: the shell states grade, wall, rib and draft; the soft body states cloth, weight and coating. Merged into "thick and durable", neither can be inspected.

Item	Injection shell	Textile body
Material	PP homopolymer, MFI 8 g/10 min	1680D polyester filament
Thickness or weight	3.0 mm wall, 3.5 mm base	1200 g/m² base cloth
Reinforcement	4.5 mm ribs at 60 mm pitch	Double-row stitch, 6 per 25 mm
Surface	Grain, 1.5 degree draft	PU coating 0.15 mm, matt
Temperature	−20 to 60 °C	−10 to 55 °C

Weight and thickness are not interchangeable. At 1200 g/m², 1680D is thicker but softer than 600D, and puncture resistance comes from yarn density; PU at 0.15 mm reaches 150,000 flex cycles against 80,000 at 0.10 mm, but cracks at winter folds.

4. Load distribution and mounting points

Weight leaves a tool carrier by handle or strap, base and side points, and the split decides where ribs and wall go.

On a hand-carry unit the handle takes everything. On a shoulder unit the strap takes the vertical load and the ears the horizontal component, amplified by walking to 1.8 times static.

Tool carrier in grey stacked five high, the middle tray open to show empty grid compartments, latches and moulded handles aligned to one side

Two rules follow: ears on one side sit 60 percent of body length apart, or the unit sways, and 20 mm from the edge, or the wall tears. Attachments stay under 3 kg per point, mounted over a rib.

5. Hardware selection and the tolerance table

Hardware often collapses into "as per sample". Latches, hinges, handles and locks each need a line: material, plating, breaking force, cycle life. A 304 latch needs 0.8 mm spring steel; 0.6 mm loses thirty percent of its force by 3000 cycles.

Item	Nominal	Tolerance	Check
Envelope length, width	480 × 320 mm	±1.5 mm	Tape, three points
Envelope height	210 mm	±1.0 mm	Height gauge
Compartment width	62 mm	±1.0 mm	Callipers, three points
Diagonal difference	none	within 2.0 mm	Two diagonals
Lid seam gap	none	within 1.2 mm	Feeler gauge
Handle hole centres	260 mm	±0.8 mm	Dedicated gauge

Tolerances separate what can be held from what must be: envelope size is the datum, compartment size governs pick-up, diagonal difference decides whether the unit rocks.

Conclusion

Tool carrier specifications multiply four actions: measure the load, fix the cavity, split the paths, lock the tolerances. The first two decide whether the unit works, the last two whether it reproduces, and in numbers a tool carrier becomes a product.

This article covers container-side specifications and design implications only, not the handling, loading or use of the contents.