Routing instructions, sequenced.
Also called: Process routing · Route card · Operation sequence · Travel sheet
The ordered sequence of operations and workstations each part passes through, with an owner and a time on every step.
A routing names every operation in order, who does it, and how long it takes. Get it down and flow becomes predictable and bottlenecks visible. Skip it and parts stall in handoffs nobody owns. There’s a worked routing below, and a checklist you can run.
What routing instructions are
A routing is the path a part takes through the operations. You list every step in the order it happens, name the workstation or partner that does it, and put a time against it. Cast, fire, ship, finish, assemble, test, pack, dispatch. Each line has an owner and a duration. Nothing more.
The point is flow. When every step has a time, you can add them up, see where the queue forms, and predict when a unit lands at dispatch. The longest step is your bottleneck, and you can only manage a bottleneck you can name. A routing without times is a wish list; a routing without owners is a finger-pointing exercise waiting to happen.
It also exposes the handoffs. Most delays in a multi-partner build don’t happen inside an operation, they happen in the gap between two of them, where a box sits on a loading bay because nobody agreed whose job the next move was. Write the route down and those gaps stop being invisible.
Routing · the proofing box
Here is the routing we ran for the proofing box, so you can see the shape of a real route card rather than a generic template. One product, four partners, every step owned and timed.
The bottleneck names itself the moment you tabulate it. Ceramic is days; everything downstream is minutes. So you schedule backwards from the kiln, and the £149 unit lands on time because the slow step never gets started late.
- Vague handoffs: “it goes to the finishers next.”
- No owner per step, so gaps belong to nobody.
- No times, so the bottleneck stays hidden.
- Dispatch dates are a guess, not a calculation.
- Every step in order, with the partner that does it.
- An owner on each operation and each handoff.
- A time on every step, so totals are addable.
- The bottleneck named, so you schedule around it.
How it fits the bigger picture
Routing instructions are activity 09.20.02 in Stage 09 Manufacture. Once the route is defined, the next activity is packaging (09.20.03), which the test-and-pack step at the end of your routing feeds straight into.
What it can do
It makes flow predictable and bottlenecks visible. Add the step times, schedule backwards from the slowest, and you get an honest dispatch date instead of a hopeful one. It tells every partner exactly what they own and when the part is due to leave them.
What it can’t do
It can’t fix a step that’s too slow; it only shows you which one to attack. And a routing is only as true as the times in it. Guessed durations give you a tidy-looking route card that lies. Measure the steps before you trust the totals.
See the full 10-stage process →
Try it yourself
Take your product and write every operation it goes through, in order, on one line each. Against every line, put the partner or workstation that owns it and a time. Add the times up. The longest single step is your bottleneck: schedule everything else around it. Mark each handoff and name who is responsible for the move, not just the work either side of it.
Want a structured first pass at your build? Start the Free Sprint → and the GPT will help you map the path your product takes.
Your routing checklist
Project notes: scheduling backwards from the kiln
▸ From the notebook · optional reading
Mapping the proofing box’s route across four partners with Dan and Anna Hartley, and the handoff gap that cost a week before we wrote it down.
3 min read · click to open
Dan thought the routing was obvious. “Cast it, build the board, bolt it together, ship it.” On a whiteboard, fine. As a schedule that has to hit a dispatch date, not even close.
What the route card actually held
Four partners, not one workshop. The ceramic shell cast and fired in Stoke-on-Trent, six days, kiln-bound and batched in fifties. The low-voltage PCB built in Manchester, four days, shipped to the finishing partner. Assembly, test against BS EN 61010, pack and dispatch, all at the finisher, all measured in minutes per unit.
The moment we put times against it, the bottleneck stopped being a debate. Ceramic is days; everything else is minutes. So you don’t schedule forwards from the order date, you schedule backwards from the kiln. Order the shells first, every time, or the whole line sits waiting on them.
The handoff that bit us
On the first pilot batch, the Manchester boards arrived at the finisher and sat for a week. Nobody had booked them in. The PCB partner thought their job ended at the courier; the finisher thought boards turned up labelled and logged. The work either side was owned; the gap between them wasn’t.
So we added a column to the route card: an owner on every handoff, not just every operation. After that, the boards were expected, booked and matched to a shell batch on arrival. I asked Dan to treat the route card as a living document and update the times after each run, because the first numbers were estimates and the real ones were what made the dispatch dates stick.
— Manufacture stage, project notes, 2026
— Next in Manufacture → Packaging