Choosing Pallets for Automated Racking and ASRS

Manual handling is astonishingly tolerant. A forklift operator sees a pallet leaning, adjusts the forks, and moves on. Automation has no such judgment. A conveyor, a shuttle, an AS/RS crane and a robotic depalletizer all assume every pallet is the same shape, in the same condition, every single time. Feed them a platform that is a half-inch out of square or missing a chamfer on a bottom board, and the machine does exactly what it was told — and jams. Understanding why automation punishes bad pallets is the whole job here.

What 'tolerance' actually means in an AS/RS

In a manual operation, a 48x40 that measures 48-and-a-quarter by 39-and-three-quarters is a perfectly good pallet. In an automated line it may be a reject. Automated systems are commissioned against a nominal footprint with a tight tolerance band — often on the order of plus-or-minus a quarter inch on length and width, and tighter still on diagonal squareness. Overhang, undersize, and racking of the frame (the pallet twisting into a parallelogram) all matter.

Height and flatness matter just as much as footprint. If bottom boards sag or a stringer bows, the pallet won't sit flat on a conveyor roller bed or transfer cleanly onto storage arms. Start with our pallet types overview to see which base configurations exist before you commit an automation spec.

The measurements automation cares about most

• Overall length and width, within a tight band (typically plus-or-minus a quarter inch).
• Diagonal squareness — the two diagonals should match closely so the pallet isn't racked.
• Bottom-board configuration and spacing, which must match conveyor rollers and shuttle arms.
• Bottom-board lead-in chamfers so the platform noses onto transfers without catching.
• Overall height and flatness — no sagging deck, no bowed stringers, no proud fasteners.
• Fastener flushness: a nail standing even an eighth of an inch proud can snag a shuttle.

Bottom-board configuration is the quiet dealbreaker

Most AS/RS failures we hear about trace back to the bottom of the pallet, not the top. Automated storage arms, shuttle wheels and conveyor rollers all contact the bottom boards. If the spacing doesn't line up with the equipment, or the leading boards lack a chamfered lead-in edge, the pallet catches on transfers. A standard block pallet with a clean perimeter base is usually the friendliest starting geometry; a stringer pallet can work but needs bottom boards positioned for the conveyor pitch.

This is also where notched stringers versus full four-way block designs come into play. The way a pallet supports its own load between rack beams governs whether it can be stored unsupported — critical in drive-in and shuttle racking where the pallet spans open space. Match that to your rated load using our load capacity explainer, because a pallet that flexes under load in an unsupported rack position is a pallet that eventually drops a corner.

“In manual racking, the operator is the tolerance. In an AS/RS, the pallet is the tolerance — there is no one there to compensate.”

Why consistency beats individual quality

Here is the counterintuitive part: for automation, a batch of merely good pallets that are all identical outperforms a batch of excellent pallets that vary. The machine is tuned to one geometry. Variance is the enemy, not wear. That is exactly why reclaimed stock — which is inherently heterogeneous, sourced from dozens of origins with different builds and different repair histories — is a hard fit for a tightly commissioned AS/RS running mixed inbound pallets.

You can absolutely run reclaimed pallets through automation, but you have to grade and sort them to an automation spec, not just a cosmetic grade. That means dimensional gauging, squareness checks, and rejecting any unit with proud fasteners or a bowed member. It is doable, and for captive-loop operations it can pay off, but it is more work than most buyers expect.

When new — or remanufactured — beats reclaimed

For most of what we do at EcoPallets Ohio, reclaimed wins on price and carbon. Automation is one of the honest exceptions. When you need a large volume of pallets that are dimensionally interchangeable to a tight tolerance, purpose-built stock is the safer call. But you don't always have to jump straight to brand-new lumber.

A remanufactured (combo) pallet rebuilt from reclaimed components to a controlled spec is often the sweet spot: you get the dimensional consistency automation demands while keeping wood in circulation. We build these to a target footprint, square them on a jig, and set fasteners flush — the properties an AS/RS actually cares about — without the full carbon and lead time of new-lumber pallets.

A quick decision path

1. 1Get the AS/RS pallet spec from your integrator — footprint, tolerance band, bottom-board layout, rated unsupported load.
2. 2Decide whether your loop is captive (you control every pallet) or open (mixed inbound). Captive loops tolerate sorted reclaimed; open loops usually don't.
3. 3For captive loops, spec sorted reclaimed or remanufactured to the tolerance band and gauge every unit.
4. 4For open, high-throughput systems, spec purpose-built pallets to guarantee interchangeability.
5. 5Regrade continuously — automation-grade pallets degrade with each cycle and must be pulled before they drift out of tolerance.

Send us your integrator's pallet drawing and your throughput, and we'll tell you honestly whether sorted reclaimed, remanufactured, or new is the right fit — and we'll build to the tolerance that keeps your machines running.