For a metal tool chest, is 1.0 or 1.2 mm the right gauge?

Answer: Match it to the drawer. Under 30 kg sustained, 1.0 mm leaves margin at 35 kg; above 40 kg take 1.2 mm and a 1.8 mm inner radius.

The sheet says 35 kg static, so how is it checked at goods-in?

Answer: Load 35 kg evenly for 24 hours, then measure deflection at the centre and four corners; 1 mm is the limit.

Is ±1.5 mm on the envelope too loose?

Answer: It is normal for laser cutting plus bending. Tightening to ±0.8 mm adds a straightening step and about 10 percent cost, while the diagonal matters more.

A castor carries 80 kg, so why rate the chest at 200 kg?

Answer: Four wheels total 320 kg on paper, but off-centre load and impact take their share; 60 percent gives 192 kg, rounded to 200.

Is 80 µm of powder coat better than 60 µm?

Answer: Past 100 µm the film turns brittle and chips in sheets on impact; 60 to 80 µm balances adhesion against corrosion.

Metal Tool Chest Specifications: Size, Gauge and Load

Quick answer: A metal tool chest specification needs four groups: envelope and tolerance, gauge and bend radius, drawer load and tiers, coating thickness. Write ±1.5 mm with a 2 mm diagonal, 0.8 mm gauge for a 25 kg drawer, 1.0 mm for 35 kg, 1.2 mm for 45 kg, and 60 to 80 µm of powder coat.

A Metal Tool Chest Specification Starts With the Envelope
Gauge: Where 0.8, 1.0 and 1.2 mm Divide
Drawer Static Load and Whole-Body Capacity
Locks, Castors and Stacking Tiers
Coating Thickness and How to Write Acceptance
FAQ

1. A Metal Tool Chest Specification Starts With the Envelope

Three dimensions are not enough. A metal tool chest must state its datum: to the outermost edge including handle and castors, or to the body alone, a 40 mm difference. Tolerances go separately: envelope ±1.5 mm, diagonal difference ≤2 mm or the rhomboid body makes drawers catch, gap 1.5 mm per side. Gauge needs a minus allowance, 1.0 minus 0.06 mm, or 0.94 mm sheet passes and carries 12 percent less.

Item	How to write it	Tolerance	Instrument
Envelope	560×330×290 mm with castors	±1.5 mm	tape and square
Diagonal	two diagonals compared	≤2 mm	tape
Gauge	1.0 minus 0.06 mm	minus only	micrometer

Measure gauge at least 20 mm away from any bend.

2. Gauge: Where 0.8, 1.0 and 1.2 mm Divide

The three gauges are load classes, not price points: 0.8 mm carries 25 kg per drawer for vehicle mounting, 1.0 mm carries 35 kg on three-section slides, 1.2 mm carries 45 kg and rides a pallet truck.

Weight follows area: 6.28, 7.85 and 9.42 kg per square metre, so 1.6 m² gains 5.0 kg from 0.8 to 1.2 mm. Inner bend radius must be 1.5 times the gauge, or the coat cracks.

Gauge	Weight per m²	Drawer load	Inner radius
0.8 mm	6.28 kg	25 kg	1.2 mm
1.0 mm	7.85 kg	35 kg	1.5 mm
1.2 mm	9.42 kg	45 kg	1.8 mm

3. Drawer Static Load and Whole-Body Capacity

A metal tool chest drawer clause needs the load, the method and the pass limit: 35 kg distributed, held 24 hours, residual deflection under 1 mm, no permanent bend in the slide.

Dynamic load is 60 percent of static, and above 50 pulls a day an overloaded raceway dents. Whole-body capacity splits into base lift at 1.25 times the rating and stacking at 1.5 times one full chest.

Test	Method	Pass limit
Drawer static	distributed, 24 h	residual ≤1 mm
Drawer dynamic	60 percent, 5000 cycles	no raceway dent
Stacking	1.5× full, 4 tiers, 24 h	lid sag ≤2 mm

4. Locks, Castors and Stacking Tiers

Lock clauses need cylinder type, bolt throw and key interchange: 12 mm of throw to bite a 1.2 mm door edge, an 8 mm padlock eye for a 6 mm shackle, and 50-key batches sampled for interchange. Castors rate per wheel, 75 mm carrying 80 kg, so four wheels plus an off-centre allowance give 200 kg; the brake must lock wheel and swivel, not the wheel alone. Stacking stops at four tiers; a fifth pushes mid-panel deflection past 2 mm and the drawer front rubs the body.

5. Coating Thickness and How to Write Acceptance

The metal tool chest coating clause is a band plus a floor: 60 to 80 µm, no reading below 50 µm, five points per face. A bare 60 µm lets a flat panel pass while the bend sits at 40 µm.

Adhesion is cross-hatch grade 1, salt spray 240 hours with rust under 5 percent of area, while zinc plating at 8 to 12 µm holds 96 hours. Bends lose about 20 percent of film to the Faraday effect, so exclude inner corners.

Process	Thickness	Salt spray	Adhesion
Powder coat	60 to 80 µm	240 h	cross-hatch 1
Electro-galvanised	8 to 12 µm	96 h	cross-hatch 2
Hot-dip galvanised	45 to 85 µm	480 h	not applicable

Conclusion

A metal tool chest specification is a set of judgeable conditions: dimensions with a datum, tolerances stated separately, gauge with a minus allowance, load with a method and a limit. Defining how each number is judged protects consistency better than tightening it, and that is what most metal tool chest documents still omit.

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.