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The guided roast

Artisan does / TilauScope adds

Artisan does — draws the curve, in real time and accurately, and leaves every decision to the roaster. What the numbers mean, and what to do about them, is yours to know.

TilauScope adds — an assistant that reads the same data against the roast plan and says what to do next: which lever, which direction, when. It announces heat reductions before they are due, states whether the roast is ahead of or behind plan, counts down to DROP and, when it is over, reports where the roast diverged from its plan.

The assistant recommends — it never moves your levers

Nothing described in this chapter touches the machine. Every instruction is for the roaster to carry out. There is no mode in which TilauScope takes the controls.

The panel

The assistant is one panel, titled ◉ ROAST ASSISTANT. It can sit docked in place of the control panel, or be detached into its own window with the ⤢ button — see Getting started. For the window around it — readouts, machine controls, the live event column — see The TilauScope window.

It follows the roast by itself, showing one page per stage: idle, preheat, drying, Maillard, development, cooling. There is nothing to switch: the page changes with the phase, so what is on screen is what matters now.

Before starting, two things are required: the coffee, from the Green Bean list, and the Target roasting level (Agtron scale). Without a coffee selected the assistant will not run — No green been has been selected — because a roast with no identity teaches the plan nothing. When the roast on screen already names a coffee — a record opened from the cellar, a replay — it is pre-selected in the list, and the line under it shows the coffee it resolved to.

The list normally offers only coffees still in stock. The one being roasted is the exception: it stays in the list even once its remaining stock has reached zero — roasting the bottom of a bag must not make the coffee disappear from its own roast — and is marked (empty stock).

In Guided level the assistant opens, starts and closes with the roast, whichever START you use: TilauScope's own, Artisan's, or the one on your phone. At Expert level it is started manually.

Coach view and Expert view

In Guided level, a small button at the top right of the graph switches between two readings of the same roast:

  • Coach view — one recommendation and a phase verdict. Nothing else.
  • Expert view — the full set of readings.

What it tells you, phase by phase

The current instruction

Recommendations are given as gestures, not analyses: one notch up on the burner, one notch down on the burner. A notch is what the machine's own controls actually allow, so the instruction can be carried out without arithmetic.

Instructions take the machine into account. On a high-thermal-mass drum the assistant asks for the step-down early — High Thermal Mass: Step down heater now to control FC entry — and on a radiant machine earlier still, ahead of first crack. The same roast on two machines does not get the same advice.

Heat reductions are announced

During Maillard, the next scheduled reduction is displayed before it is due, as next 48% @170° — the power level and the bean temperature that triggers it. The heat profile stops being a surprise: what is coming is on screen, with time to prepare for it.

Airflow, by phase

Airflow guidance changes with the phase — keep low to conserve heat while drying, moderate for even drying, then raise to manage browning & chaff — and the assistant warns when a fan change would cost more than it gains: Airflow is high-impact: Avoid fan changes to keep RoR smooth.

Hardware — AirWave

With a DiFluid AirWave extractor paired, its mode can be changed from the panel itself (MODE STD / MODE EXT), without leaving the roast screen. See Hardware and peripherals.

Advice specific to this coffee

The guidance carries the coffee's own properties: dense bean → needs sustained heat, low density → heat transfer faster, humid → keep RoR moderate, longer drying ahead, dry beans → watch for flash drying, natural/honey process → extended drying phase expected. Two coffees at the same batch size are not steered identically.

Where the roast stands

Against the plan. During drying and Maillard the assistant states the lead or lag against the planned curve — plan +0:15 — or simply on plan / ON PLAN ✓.

Against the expected slope. RoR is judged at the point on the curve the roast has actually reached, not against a fixed number: RoR IN BAND / RoR OUT OF BAND, with the band itself shown as Ideal interval 12–15 °/min. This is why the assistant does not call a roast "too fast" early in Maillard when that slope is exactly what the plan asked for.

In plain terms. Readings come with their consequence: RoR is high → volatile aromas escaping, RoR too low → risk of baked coffee, RoR increasing — look after the slope.

Milestones ahead. DRY END ~1:20, FCs ~2:45, and when they arrive, now.

Marking milestones

When a milestone is detected, the assistant does not mark it for you. It proposes: the relevant button turns prominent, a prompt appears, and it beeps once. Confirming is a click — on Mark DRY END, Mark FC START or Mark DROP. The roaster stays the authority on what happened in the drum.

Each confirmed milestone re-plans the rest of the roast against reality, so targets and estimates after it are recomputed rather than left stale.

Charge is marked from the panel too. If it was marked by mistake, Cancel charge appears for 15 seconds and undoes it.

Finishing the roast

The DROP countdown — DROP ~0:45 — accounts for the curve flattening out at the end, so it does not promise a drop that is still two minutes away. Under twenty seconds it says so plainly: ⏱ DROP in less than 20 seconds — get ready!

Development is tracked against its target as it happens: DTR ON TARGET, DTR near target, DTR OFF TARGET, DTR DRIFTING. The DTR the roast is heading for is visible while there is still time to influence it.

Hardware — colour reader

With a colour sensor fitted, colour is followed live against the target — color in target range, too light, too dark, and in target range → envisage DROP. It is one more input to the drop decision, not a replacement for it. See Hardware and peripherals.

When something goes wrong

The assistant raises problems while they can still be fixed.

Alert What it means
⚠ RoR crash detected — DROP now or start heating again! The roast has crashed. Two ways out, both stated.
↩ Recovery — RoR rebuilding after turning point Not a fault — the normal rebuild after TP.
⚠ Extended drying: ~5:30 vs plan 4:45 — baked risk, raise heater Drying is running long enough to risk a baked cup.
⚠ Extended Maillard — baked risk, raise heat or anticipate FCs The same problem, one phase later.
⚠️ Premature browning detected! The opposite: the roast is developing colour too early.
Flash drying risk — check FIR power Surface drying ahead of the core. See flash drying.
⚠ Critical Gap between ET/BT — dangerous thermic gradiant The two probes have diverged dangerously.

Alerts name the correction, not just the condition — raise heater, reduce heater, DROP now or start heating again. An alert you cannot act on is noise.

Alarms behave differently in Guided

At Guided level, the alarm actions configured in Artisan do not fire, so that two sources of instructions cannot contradict each other. See Getting started.

Cooling, and the next batch

At DROP the assistant moves to its cooling page and stays useful: Open drum door & cooling tray, keep drum spinning. Don't cut main power until BT < 50°, with COOLING / NOT COOLING state and, if the beans are not cooling, an unambiguous ⚠ BEANS NOT COOLING - RISK OF FIRE.

For a second batch on a hot machine, Restart batch handles the whole turnaround on the same coffee: it stops and saves the roast, resets, re-injects the same coffee and the same charge weight, and starts preheating. Below the cooling threshold it goes immediately; above it, the click arms the sequence — cooling continues and the relaunch fires on its own when the threshold is crossed. A second click disarms it.

Note

A batch relaunched this way is saved without its result form, so its finishing details — weights, colour, notes — are simply filled in later, from Repair ALogs. Nothing is lost. See After the roast.

After the drop

ROAST SUMMARY compares what happened to what was planned, phase by phase: Actual BT and Actual RoR against the plan, each phase reported as having run hotter or cooler, and a verdict — Trajectory well held across all phases, Well held — slight drift in Maillard, or Marked drift in Maillard. This is the sentence worth reading: it says which phase to attend to next time.

Colour closes the loop. The colour recorded here — measured or judged — corrects the drop target of the next plan for this coffee. See The roast plan.

Notes are recorded against the roast, while the detail is fresh.

🚫 Exclude from learning keeps a roast out of the plan's history. A batch that went wrong for reasons that have nothing to do with the coffee — an interruption, a mistake, a probe problem — should not become a reference. This is the switch that protects every future plan for that coffee.

Machines TilauScope cannot drive

On a read-only roaster, the control sliders are absent and the assistant gives recommendations to act on by hand instead. Everything else in this chapter — plan tracking, milestone suggestions, alerts, the countdown, the end-of-roast summary — works exactly the same, because it all comes from reading BT and ET, not from driving the machine.

Alarms written as sentences

TilauScope can express alarms as readable rule sentences — IF ALARM / IF NOT ALARM — rather than as rows in a table, and can show the resulting strategy as a narrative before the roast starts. The alarms themselves are Artisan's; what changes is that the rule can be read back and checked.

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