How to Specify a Custom Aluminum Case: The Complete RFQ Checklist

Every week, aluminum case manufacturers receive inquiries that read something like this: “Please quote a custom aluminum case for our equipment.” The intent is good, but the information is not. Without dimensions, weight, protection requirements, and order quantity, no factory can price accurately – and the back-and-forth that follows can add weeks to a project that should move in days.

The buyers who get the best cases, the fastest quotes, and the most competitive prices are the ones who submit a complete specification on day one. This guide walks you through every decision a professional RFQ should cover, in the order an engineer would ask about them. Work through it once, and you will never write a vague case inquiry again.

Step 1: Define Exactly What You Are Protecting

Everything in case design flows from the payload. Start by recording the equipment’s maximum length, width, and height in millimeters or inches – including every protrusion: connectors, antennas, handles, knobs, and cables that must stay attached. A dimension taken “body only” is the single most common cause of a case that arrives too small.

Next, record the weight. This drives wall thickness, hardware load ratings, and whether the case needs wheels or a trolley system. Finally, assess fragility: a rugged power tool tolerates very different shock levels than a calibrated measurement instrument. If your equipment has a published shock or vibration limit (for example, 50 g maximum), include it – this number lets the case engineer size the foam cushioning precisely instead of guessing.

Step 2: Choose the Case Construction

Two constructions dominate professional aluminum cases. Sheet aluminum cases use folded or welded aluminum alloy sheet (typically 5052 or 6061, 1.0-2.0 mm thick) and deliver maximum rigidity and the cleanest appearance – ideal for instrument cases, medical cases, and presentation applications. Panel-and-frame (flight case) construction bonds plywood, plastic, or aluminum composite panels into an extruded aluminum edge frame with ball corners – the touring industry standard for flight cases that survive hundreds of load-ins.

If weight is critical, ask about aluminum honeycomb or composite sandwich panels, which can cut case weight by 30-40% versus plywood panels at similar stiffness. If your case will live outdoors or on ships, specify welded seams and corrosion-resistant alloy from the start.

Step 3: Specify the Interior

The interior is where protection actually happens. Custom foam is the default choice for anything fragile or valuable: polyethylene (PE) foam for repeated use and heavier equipment, polyurethane (PU) foam for lightweight, delicate items, and EVA foam when appearance matters as much as cushioning. State your preference, or simply describe the equipment’s weight and fragility and let the factory’s engineers select the foam density and thickness.

Not every case needs full foam. Tool cases often work best with removable tool pallets, elastic straps, and dividers. Demo and sales kits may need a combination: foam below, a product display panel above. List every item that must live in the case – accessories, cables, manuals, chargers – so nothing gets forgotten in the layout.

Step 4: Hardware, Mobility, and Security Options

Hardware selection depends on how the case will be handled. A case under 10 kg needs only a comfortable handle; beyond roughly 15-20 kg, specify recessed handles, edge casters, or a telescoping trolley system as found on dedicated trolley cases. For latches, choose between standard draw latches, lockable versions, or butterfly latches for flight-case duty.

Security requirements deserve explicit attention. If the case travels unattended, specify key locks or padlock hasps. Firearm transport has its own regulatory requirements – purpose-built gun cases with locking points are the correct starting point there. And if the case will fly, a pressure equalization valve prevents vacuum-lock after altitude changes.