Contract Packager Palletizer: How Co-Packers Automate Case Stacking for Changing Clients

A contract packager does not run one product all year. One week the line packs food cases for one client, the next it runs beverage or cosmetics cases for another — different sizes, patterns and stack heights, sometimes on the same shift. Hand-stacking absorbs that change, but at a cost: heavy lifting all day, inconsistent pallets, and a line that slows whenever staffing is short. Here is the fit check before automating that job.

Why co-packing is the hardest test for a palletizer

A dedicated line can be tuned once and left alone. A co-packing line cannot. Client work arrives in runs, promotional and club formats appear alongside standard retail cases, and a pattern that was right on Monday may be wrong on Thursday. Any palletizer there has to handle change as a normal part of the day. That makes two things decisive: honest sizing across every case in scope, and fast, repeatable changeovers. The question is not only whether a cell fits today’s largest client, but whether it will still fit the next client and the next short run — without a rebuild each time.

Check 1: Size client by client, not by your average case

Start with the five sizing numbers we set out in Pallet Patterns and Case Sizing: case length × width × height, heaviest sealed-case weight, sustained cases per minute, cases per pallet, and pallet size. Collect them per client and per format, not as one blended average. The heaviest case, the tallest stack and the fastest sustained run in your real mix are the numbers that decide fit.

Our base rental cell handles cases up to 20 kg (44 lb), with robot reach up to 1,880 mm. Size to the heaviest sealed case in scope. If a client’s heaviest case is above 20 kg, or a job needs stacking heights above the standard setup, raise it at the first walkthrough: Dorna’s cobot cells can be customized for cases up to 50 kg and for stacking heights above 8 ft, and custom systems are priced after a free walkthrough, an initial estimate and a custom design. Settling that early avoids quoting a client job around a cell never sized for it.

Check 2: Make recipes, not re-teaching, your changeover

On a multi-client line, changeover time is real capacity. Each format should get its own stored pallet pattern — a recipe — covering case size, cases per layer, layers per pallet and placement positions. Changing jobs then becomes selecting the recipe and confirming the first case, instead of re-teaching positions by hand.

Agree the rules before install day: who selects the recipe, how the last part-finished pallet of the previous job is cleared and labelled, and how a new format gets added and tested. Keep a simple list at the line — client, format, recipe name, pallet size — so any shift runs the same changeover the same way.

For the cycle-time thinking behind that, see How Many Cases Per Minute Can a Cobot Palletizer Handle? — and size to your sustained rate across changeovers, not to a peak rate from one clean run.

Check 3: Confirm footprint and utilities on a shared floor

Contract packaging floors are shared and busy, and the end of the line is rarely empty. A cobot cell helps because it is compact: a typical footprint is about 3,000 × 3,000 mm, with two pallet stations of 1,100 × 1,100 mm, a conveyor infeed at the top centre, and a safety light curtain on the open side. Each cell needs 110 V power, max 15 A, plus a compressed-air connection — utilities most plants can provide at the line end without a major project.

Place the cell where sealed cases already travel, after the case packer or sealer, without blocking forklift routes, staging areas or emergency exits. Remember the layout rule: a single fixed cobot places to its left and right only, so two pallet stations are the standard layout; serving four pallet positions takes a linear rail or a second robot. A clear photo of your line end, with rough dimensions, is the fastest way to confirm the layout before a site visit.

Check 4: Settle safety and pallet quality when crews rotate

Collaborative does not mean “no assessment needed.” Work through the risk assessment for your floor: who works near the cell, how pallets are exchanged during a run, and whether safety guides or a cage are needed for your layout or a client’s audit requirements. Guides and a cage are options fitted when needed; the base offer is pitched without them, and the typical layout includes a safety light curtain on the open side. Our guide Are Cobot Palletizers Safe? walks through that assessment step by step.

Pallet quality matters to clients, not just to the warehouse. Layers should be square, stable and repeatable so pallets wrap cleanly and travel well. If a job uses light or presentation-sensitive cases, say so early — our cosmetics palletizer guide and food plant guide cover those angles — so grip and placement are planned for the case, not discovered on the first run.

Check 5: Plan delivery and installation around booked work

Delivery is typically 3–4 weeks. The robot ships on a wooden pallet; receiving delivery and providing a pallet jack on site, at a delivery time coordinated in advance, are the customer’s responsibility. Siamak personally attends installation, start-up, training and pallet-pattern recipe creation, so the first recipes are built and tested on your floor, with your cases.

Palletizer Installation: What to Expect covers the sequence in full. For a co-packer, schedule install in a gap between booked runs where possible, and have the first formats’ cases and pallets ready to test. Billing and the rental term start at installation and start-up — not at order, and not while the robot is in transit.

Why co-packers often rent the first cell

Client mix changes, so flexibility has value beyond the first job. A palletizer rental at $1,999/month with zero upfront, installation and maintenance included, lets a co-packer prove the cell on real client work — heaviest case, real sustained rate, real changeovers — without a large upfront purchase tied to one client’s contract. That is the base cell price; quarterly, semi-annual and annual prepay options are also available. Purchase and rent-to-own are also available — ask us for a quote.

If you are comparing paths, Palletizer Rent vs Buy and How Much Does a Robotic Palletizer Cost? compare the options side by side, with illustrative figures labelled as illustrative. Our California Palletizer and Arizona Palletizer guides run similar checks for plants in those states.

The bottom line

For a contract packager, the fit check is five questions: Have you listed every client format in scope and weighed the heaviest case? Do you know your sustained rate across changeovers, not just your peak? Will each format get its own recipe, with clear changeover rules? Is about 3,000 × 3,000 mm, 110 V power and compressed air available at the line end? And are you ready to receive the robot on a pallet, with a pallet jack, in 3–4 weeks? Answer those, and you can give every client what hand-stacking struggles to deliver on a changing line: consistent, well-built pallets, run after run.