AMS & Humidity Monitoring¶

Bambuddy provides comprehensive monitoring for your AMS (Automatic Material System) and AMS-HT (High Temperature) units.

AMS Slot Status¶

Each AMS slot displays:

Slot hover card¶

Hovering a slot opens a card headed by the filament's colour, with the profile, K factor, fill level and — when a spool from Inventory is bound to the slot — the spool's own name.

The header shows the spool's colour, not the printer's. A printer reports one hex per tray and nothing else, so a multi-colour roll would otherwise read as a single flat band. When the bound spool carries Extra colours or an Effect, the header paints that spool's full swatch — the same gradient, colour wheel or effect overlay the Inventory page draws — and the colour name is the one you gave the spool rather than whatever Bambu calls that hex. A plain single-colour spool, and any slot with no spool bound, is unchanged.

RFID Re-read¶

Refresh filament information for individual AMS slots:

1. Hover over an AMS slot on the printer card
2. Click the menu button () that appears
3. Select Re-read RFID
4. A loading indicator appears while the printer reads the RFID tag
5. Filament information updates automatically when complete

Load / Unload Filament¶

Drive Load and Unload directly from any AMS slot or external spool — no need to walk to the touchscreen:

1. Hover over an AMS slot or external spool on the printer card
2. Click the menu button () that appears
3. Select Load to feed that tray, or Unload to retract whatever is currently loaded

Configure AMS Slot¶

Manually configure AMS slots for third-party or generic filaments. This tells the printer which filament profile to use for a specific slot (temperatures, flow rate, pressure advance).

1. Hover over an AMS slot on the printer card
2. Click the menu button () that appears
3. Select Configure Slot
4. Choose a filament preset (from Bambu Cloud, local OrcaSlicer imports, or the built-in Bambu filament catalog — see preset sources)
5. Select a matching K profile (pressure advance calibration)
6. Optionally set a custom color using the color picker
7. Click Configure Slot to apply

Color Picker Features:

• 8 basic colors shown by default (White, Black, Red, Blue, Green, Yellow, Orange, Gray)
• Click + to expand 24 additional colors
• Enter custom hex codes or color names (e.g., "brown", "FF8800")
• Live preview of selected color

Why the Printer May Still Show a Generic Filament¶

Bambuddy's slot card, the printer's own screen and Bambu Studio's Device tab are not answering the same question. Bambuddy shows the preset you picked, which it stores next to the slot. The printer and the slicer show whatever the printer could resolve from the slot's filament ID — an eight-character field that is the one thing a filament choice travels in.

So the three can legitimately disagree. A slot that reads as your custom preset in Bambuddy while both the LCD and Bambu Studio say Generic PLA is almost always one of the two cases below, not a setting that failed to arrive.

1. The preset has no filament ID of its own.

A custom preset only becomes a filament in its own right when it carries its own ID — a P followed by seven hex characters. Bambu Studio mints one when you create a genuinely new filament. It does not when the preset merely overrides a few fields of a generic base. An OrcaSlicer preset synced to Bambu Cloud has no such field at all; one synced to Orca Cloud usually carries one, and Bambuddy reads it from there.

With no ID of its own, there is nothing custom to send. Bambuddy leaves the slot on an ID that does resolve — the one the slot already had, or the generic for that material — so the printer's calibration table and the slicer's filament matching keep working. The name they show is that filament's, not your preset's. Bambuddy still sends the preset's full cloud ID alongside it, which is what lets Bambu Studio pick your settings up when it can.

2. The printer has never seen the preset.

Even a preset that has its own ID is only a name the printer can print on its screen once it has fetched your filament list from Bambu Cloud. It does that when you open the filament settings screen on the printer while it is connected to the cloud.

Developer Mode — which Bambuddy needs in order to control the printer at all — is LAN-only. Bambu state it plainly: Developer Mode "will not allow the printer to be connected to Bambu Cloud, so it is exclusively working in LAN Mode" (Third-party Integration). A printer that has only ever run in Developer Mode has no custom-filament data to resolve against and falls back to the material.

Bambu document the way around it on Problems and solutions for Custom Filament: create the preset with the printer in cloud mode, then "go to the printer screen to select the Filament" — entering that screen is what saves the filament data onto the printer itself. Afterwards the printer can name it in LAN mode too.

Printer Model Filtering¶

Filament presets in the Configure AMS Slot modal are automatically filtered by the printer model. This means you only see presets that are compatible with the printer you are configuring:

• Cloud presets are matched by the model suffix in the preset name (e.g., @BBL X1C, @BBL P1S, @BBL H2D). Generic presets without a model suffix are always included.
• Local presets are filtered by their compatible_printers field to show only those that list the current printer model.
• The currently-configured preset for the slot is always shown in the list, regardless of model filter, so you can see what is already set even if the preset would otherwise be filtered out.

This filtering reduces clutter and prevents accidentally selecting a preset intended for a different printer.

The picker also filters by the nozzle diameter actually installed on the printer, not a fixed 0.4 mm. If you have a 0.6 mm nozzle fitted, you'll see the 0.6 mm profiles for your trays; on a dual-nozzle H2D each AMS shows the profiles for the nozzle that feeds it. Configuring a slot with a profile that doesn't match the installed nozzle is what causes the printer to reject a print with "Failed to get AMS mapping table" — see Troubleshooting.

Which K Profiles Are Offered¶

The K Profile (Pressure Advance) dropdown lists the calibrations stored on the printer itself, narrowed to the ones that suit the filament preset you picked above it. A profile is offered when either of these holds:

• Its filament ID matches the selected preset's. This includes Bambu's generic IDs — a slot set to Generic PLA offers every profile the printer calibrated under Generic PLA, whatever you named them. This is how Bambu Studio's Flow Dynamics list behaves, because the printer keeps one calibration table per filament ID.
• Its name matches the preset's material (and brand, when the preset names one). This is the fallback for printers that report no filament ID with their calibrations.

The profile currently bound to the slot is always shown, even if it matches neither rule, so the dropdown always reflects what the printer is actually using.

Below those, Other K profiles on this printer lists everything else the printer holds. Profile names are free text — a calibration named after its colour ("Dark Brown", "Marble") carries nothing that ties it to a material — so this group guarantees any profile on the printer can be selected. Picking one from it works exactly like picking a matching one: Bambuddy realigns the slot's filament context to the profile so the printer keeps the selection.

Pre-Population for Configured Slots¶

When you open the Configure AMS Slot modal for a slot that already has a configuration, Bambuddy pre-populates the form fields so you can review or adjust the current settings without starting from scratch:

• Filament preset — The previously-configured preset is pre-selected. Bambuddy resolves this from the saved preset mapping or by matching the slot's tray_info_idx to the corresponding preset.
• Color — The color picker is pre-populated with the slot's current filament color.
• K-profile — The active pressure advance profile is pre-selected by matching the slot's cali_idx to the available K-profile entries.
• Auto-scroll — The preset list automatically scrolls to the selected item so it is visible without manual scrolling.

Multi-AMS Support¶

Bambuddy supports multiple AMS units per printer:

• Up to 4 AMS units (16 total slots)
• Each unit displayed with its slots
• Visual indication of active slot during printing

External Spool Holders¶

Printers without an AMS (or with filament loaded outside the AMS) use an external spool holder. The H2D is a dual-nozzle printer with two external spool positions — Ext-L (left) and Ext-R (right) — each feeding its respective nozzle. Bambuddy displays both external slots and supports configuring, color-setting, and K-profile assignment for each one independently.

Hiding it from the printer card¶

If you never feed filament from the external holder, its card is just taking up room next to your AMS units. The eye icon at the right-hand end of the Filaments header hides it; click it again to bring it back. The choice is remembered per printer and per browser, so it does not affect anyone else using the same Bambuddy.

AMS Filament Backup¶

Bambuddy reads and controls the printer's per-printer AMS Filament Backup setting (BambuStudio's "Auto switch filament" / auto_switch_filament). When enabled, the printer automatically switches to a matching spool in another slot once one runs out, so a long print can roll across multiple spools of the same filament profile and colour.

Status badge¶

The Filaments section header on each printer card carries a small badge:

Click the badge to open the AMS Filament Backup modal.

Backup modal¶

A BambuStudio Auto Refill-style view of every backup pair currently formed on the printer.

• Toggle row at the top with the current ON / OFF / unsupported state and the same setting wired to the firmware via MQTT.
• One ring per backup pair, modelled on BambuStudio's "Auto Refill" widget. The ring is filled with the actual filament colour; the material name and rotation count (N× ↻) sit in the centre; member slot labels (e.g. A·1, B·3) sit on contrast-aware pills distributed around the colour band. Lone slots (no peer) are deliberately not listed — if a slot doesn't appear in any ring, it has no backup.
• R / L badges on each ring only render on dual-extruder printers (H2D / H2C / X2D) when the extruder map carries two distinct values; single-nozzle printers or printers with routing data not yet reported don't see the badges.
• Esc, click-outside, or the close button dismisses the modal.

Pairing rule¶

Two slots pair when they share the same Bambu filament preset ID (tray_info_idx, e.g. GFA00) AND the same colour (alpha-normalised — 1A1A1AFF matches 1A1A1A). This mirrors the firmware's own switch decision.

• Three PETG HF spools in different colours don't back each other up. The firmware would correctly swap PETG HF but the print would change colour mid-run.
• User-tagged spools without a Bambu preset never pair with anything else. The firmware backup logic relies on the preset, and pairing on cosmetic name match alone risks treating two visually-identical but materially-different spools as backups.
• On dual-extruder printers, pairing is scoped per extruder side. Two same-(preset, colour) slots on opposite extruders aren't peers — the firmware can't cross.

Backup-aware "insufficient filament" check¶

The pre-dispatch deficit check that gates "Print Now" / "Send" buttons (and the queue dispatcher) is backup-aware, and so is the "Not enough filament" warning the print dialog raises before it queues anything.

When AMS Filament Backup is ON, the deficit check pools remaining grams across same-(preset, colour) spools on the printer (per extruder side on dual-nozzle) before declaring a shortfall. So a 200 g print routed to a slot with 10 g remaining no longer gets blocked when a peer slot holds the same filament with 500 g spare — the firmware will swap automatically. If the pool genuinely can't cover the print, the dialog quotes the pooled totals rather than the mapped slot's own remaining weight.

When AMS Filament Backup is OFF, the check falls back to strict per-slot accounting — there's no peer to roll to, so an empty slot would actually stop the print.

This works both in internal-inventory mode (via the local Spool table) and Spoolman mode (via Spoolman's filament.id + color_hex). Which spools count as backups for each other is decided in one place on the server, by the same code the dispatcher uses, and handed to the print dialog — so the dialog can't disagree with what the queue will actually do.

Interaction with "Prefer Lowest Remaining Filament"¶

The Prefer Lowest Remaining Filament setting (Settings → Filament) tells the AMS auto-mapper to pick the spool with the least remaining weight first — useful for finishing off near-empty spools so they don't accumulate. This only makes sense when AMS Filament Backup is ON, because without backup the printer will stop on the first empty spool, defeating the purpose.

When AMS Filament Backup is OFF, Bambuddy automatically suppresses the prefer-lowest sort (both backend dispatcher and the PrintModal mapping UI honour this) so it won't reach for a near-empty spool the printer can't roll off of. The setting itself isn't hidden — flip Backup back on and it takes effect again immediately.

With Backup ON, prefer-lowest picks the lowest-remaining slot within the same (preset, colour) group — so when the picked slot empties, the firmware swaps to the same-colour peer that holds more material. If only one same-(preset, colour) slot exists, prefer-lowest can't pick anything riskier than that one, and the backup-aware deficit check still catches the case where it's short.

Humidity Monitoring¶

Track humidity levels inside your AMS units:

Current Reading¶

The humidity percentage is displayed on the printer card:

Configurable Thresholds¶

Set custom warning thresholds in Settings:

1. Go to Settings > General
2. Find AMS Humidity Threshold
3. Set your preferred warning level
4. Save changes

Temperature Monitoring¶

For AMS-HT (High Temperature) units, temperature is also tracked:

Temperature thresholds and the alarm¶

Settings > AMS Display Thresholds > Temperature has three fields, and they do different jobs:

Leave Alarm above empty and the alarm uses the Fair threshold, which is how Bambuddy behaved before the field existed — so nothing changes for an install that never sets it.

One value covers every printer and every unit, AMS-HT included — there is no per-printer or per-unit override. Nothing requires it to sit above the Fair band either: set it lower if you would rather hear about a unit before the reading changes colour. Zero or less is refused and falls back to Fair, since zero would alarm permanently and is far more likely to be a cleared field than a choice.

Remote AMS Drying¶

Control AMS drying directly from Bambuddy — no need to use the printer's touchscreen. Start, monitor, and stop drying sessions for AMS 2 Pro and AMS-HT units.

Supported Hardware¶

Remote drying requires an AMS unit with built-in heating:

Printer Firmware Requirements¶

Not all printers support remote drying commands. The following minimum firmware versions are required:

Power Supply Requirements¶

AMS 2 Pro and AMS-HT units require an external power supply (PSU) to run the drying heater. Without it, the AMS can only monitor humidity — it cannot actively dry.

The printer firmware reports power constraints via the dry_sf_reason field per AMS unit. Bambuddy reads these automatically:

When any of these is reported, the drying button is disabled and its tooltip names the reason: "Connect AMS power adapter to enable drying" for the two power codes, "Retract the filament at the AMS outlet to start drying" for a consumable at the outlet, and "AMS can't start drying right now" for the rest. This applies to manual drying, queue auto-drying, and ambient drying — the scheduler skips AMS units with active dry_sf_reason entries.

HMS Error Codes (AMS Power)¶

When the AMS encounters a power-related issue, the printer reports it as an HMS (Health Management System) error. These appear in Bambuddy's HMS error panel:

AMS 2 Pro Errors:

AMS-HT Errors:

Starting a Drying Session¶

1. Find the AMS 2 Pro or AMS-HT card on the Printers page
2. Click the flame icon in the AMS card header
3. In the drying popover:
   • Select filament type — Choose from PLA, PETG, TPU, ABS, ASA, PA, PC, or PVA
   • Temperature — Auto-set from BambuStudio official presets; adjust manually with the slider or input field
   • Duration — Auto-set from presets (1–24 hours); adjust as needed
   • Rotate spool — Optionally enable spool rotation during drying for more even heat distribution. Off by default. The toggle is automatically disabled (greyed out, with a tooltip) when any tray in the targeted AMS has filament threaded into the feed tube — the whole AMS rotates as one mechanism, so a single loaded slot mechanically locks the entire unit. The submission also clamps the value off in that state to prevent a stale toggle from leaking through
   • Start time — Choose when to start drying (now, after a delay, or at a specific time). Pending scheduled drying sessions are displayed in the printer card and can be cancelled from there with the × button.
4. Click Start (or Schedule for drying sessions scheduled for a future time).

When a Scheduled Session Starts¶

The time you pick is the earliest start, not an exact one. A session starts on the first scheduler pass after that time when the printer is idle and the AMS is ready to dry. It can start later than the time you chose, and there is no limit on how much later.

While a session waits, the printer card says why it has not started. Most reasons clear by themselves — Waiting for the printer to come online, to be free, for the current drying cycle to finish, or for the AMS to be detected, and AMS can't start drying right now for the transient AMS states in the dry_sf_reason table above.

Two of those states need you to act, and the session waits indefinitely until you do:

• Connect AMS power adapter to enable drying — codes 1 and 8
• Retract the filament at the AMS outlet to start drying — code 3

A session can also fail. The usual cause is firmware too old for remote drying, which Bambuddy cannot check if the printer was offline when you scheduled. A session also fails when the printer accepts the command on an idle printer but the AMS never starts drying (see "Drying not running"). The card shows the failed session in red with the reason, in your language. Clear it with the × button.

Monitoring Drying Progress¶

When drying is active, a status bar appears between the AMS header and slot grid:

• Time remaining — Countdown in hours and minutes (e.g., "3h 42m" or "42m")
• Filament and target temperature — e.g. "PLA @ 45°C", when Bambuddy knows them
• The flame icon in the header turns amber to indicate active drying

"Drying not running"¶

A printer sets an AMS unit's drying countdown as soon as it accepts a drying command, and a running cycle counts it down once a minute. If the countdown has not moved for 150 seconds and the AMS reports no Checking, Drying or Cooling phase, Bambuddy shows a grey Drying not running badge instead of the amber one. The countdown is hidden, because it is not counting, and hovering the badge explains why. The × button still stops it.

There are two ways to get here, and they look the same:

• The cycle never started. The printer took the command but the AMS never began heating. This was seen on an H2D during a print: two AMS-HT units were drying, and a third unit's timer sat at 720 minutes without heating.
• The cycle was paused partway, for example by the power limit or the current print.

As soon as the AMS reports an active phase, or the countdown moves again, the badge goes back to the amber Drying state on its own. A phase the AMS reports always wins over the 150-second rule. After Bambuddy restarts, the 150 seconds start again.

If a unit stays on this badge, make sure the AMS has power and, if a print is running, wait for it to finish. If drying still doesn't start, stop it with × and start it again.

A timer like this never reaches zero, so Bambuddy doesn't wait for it to end:

• In blocking mode, a printer whose only drying timers are not running doesn't hold the queue.
• A scheduled session whose timer stops running goes back to pending if a print is running, and runs again once the printer is free. On an idle printer it fails with The printer accepted the command, but the AMS did not start drying. Either way the timer is left on the printer, since it may still start once power frees up.
• The AMS high-temperature alarm is not held back for a unit that isn't actually heating.

Stopping a Drying Session¶

• Click the × button on the drying status bar, or
• Click the flame icon (when drying is active, it acts as a stop button)

Permissions¶

Queue Auto-Drying¶

Automatically dry AMS filament between scheduled prints. When a printer is idle and humidity exceeds the configured threshold, Bambuddy starts a drying session to keep filament in optimal condition before the next print begins.

How It Works¶

1. The scheduler checks idle printers that have scheduled queue items
2. For each AMS unit, it reads the current humidity level
3. If humidity exceeds the Fair (orange) threshold from Settings, drying is triggered
4. The drying temperature and duration are determined by the loaded filament types using the configured drying presets
5. Drying runs for the preset duration — the printer stops it automatically when the cycle completes
6. When the next scheduled print is ready to start, any remaining drying is stopped and the print begins

Conservative Temperature Selection¶

When an AMS unit contains mixed filament types (e.g., PLA and PETG in the same unit), the scheduler uses conservative parameters:

• Temperature — The lowest temperature across all loaded filaments (to avoid overheating sensitive materials)
• Duration — The longest duration across all loaded filaments

Per-Filament Humidity Threshold¶

A single global humidity threshold is a poor fit for multi-material print farms — Nylon wants to stay under 20%, PLA is happy at 60%, ASA somewhere in between. Bambuddy lets you set a different trigger threshold per filament type, in addition to the conservative drying temp/duration above.

Configure overrides in Settings > Workflow > Queue Auto-Drying in the table directly below the Drying Presets table:

• Empty / unset — the editor pre-fills from your global AMS Humidity Threshold (Fair) value, so the upgrade is silent. You only need to touch the rows for materials you want to treat differently.
• Range — 5 % to 95 %.
• Clearing a row (delete the value, click away) resets that row to use the Default row.

Mixed-AMS Resolution: Most-Restrictive Wins¶

When one AMS unit holds different filament types, Bambuddy picks the lowest threshold across the loaded spools. A unit with PLA at 60 % and Nylon at 20 % triggers drying when humidity exceeds 20 % — the Nylon's level — protecting the most sensitive material in the unit.

This matches the conservative-params strategy used for drying temperature and duration above. If you want a dedicated humidity profile per material, dedicate one AMS unit per filament type.

What the Override Drives¶

The per-filament threshold is read by both:

1. The auto-drying scheduler — decides when to start, stop, and skip drying per AMS.
2. The hourly humidity alarm notifier — fires on_ams_humidity_high / on_ams_ht_humidity_high (see Notifications).

Both consumers go through the same resolver, so they can never disagree on whether a given AMS is "too humid."

Enabling Auto-Drying¶

1. Go to Settings > AMS Display Thresholds
2. Set the Fair (orange) ≤ humidity threshold — this is the trigger point for auto-drying
3. Go to Settings > Workflow and find the Queue Auto-Drying card
4. Enable Enable auto-drying
5. Optionally enable Wait for drying to complete (blocking mode)

Blocking vs Non-Blocking Mode¶

When Auto-Drying Stops¶

Auto-drying is stopped automatically when:

• The drying cycle completes — drying runs for the preset duration and the printer stops it when the cycle finishes
• A scheduled print is ready to start (non-blocking mode)
• The queue item's schedule is removed or changed to "Queue Only"
• All scheduled items are removed from the queue
• Auto-drying is disabled in Settings

Don't set the threshold below 20%¶

An AMS reports a higher humidity while it is warm than the same unit reports once it has cooled. A measured example: an AMS 2 Pro that reads 10-13% cold sat at 15-20% throughout every drying cycle. Moisture driven out of the spools has to go somewhere, and until it vents it is in the air the sensor is measuring.

That matters because the threshold is checked again the moment a cycle ends. Set it to 14% and the reading at that moment is still 15-16%, so a new 12-hour cycle starts immediately — and the firmware, which ends a cycle when it judges the filament dry rather than when the clock runs out, ends that one early too. The result is a cycle every few minutes that never gets anywhere.

Bambuddy guards against this from both ends:

• Settings warns you when the Fair threshold is below 20%.
• A cooling-off period. After a cycle ends, the same AMS unit will not be armed again for 30 minutes — the humidity reading is not worth acting on until the box has cooled.

• It gives up rather than loop. After two cycles in a row that make no progress, Bambuddy stops arming that unit, logs why, and sends an Auto-drying suspended notification (see Notifications). The suspension lifts on its own as soon as the reading falls below the threshold.

  Progress is measured against the lowest reading any cycle on that unit has ended at, not against the threshold. A genuinely wet spool in a humid room comes down slowly — 40%, 37%, 35% — and keeps drying for as long as it is still coming down, however far it still is from your threshold. What stops is a unit whose cycles end exactly where the last one did. Comparing against the best reading so far rather than the previous one means a sensor wobbling by a point between two values doesn't read as progress every other cycle.

None of these ever stop a cycle that is running. A dry you started by hand, from Bambu Studio or from the queue is untouched.

Requirements¶

• At least one scheduled queue item (items in "Queue Only" mode do not trigger auto-drying)
• AMS 2 Pro or AMS-HT unit (original AMS does not support drying)
• Supported printer firmware (see firmware requirements above)
• Humidity above the Fair threshold

Ambient Drying¶

Automatically dry filament on any idle printer whenever AMS humidity exceeds the configured threshold — no scheduled prints required. While queue auto-drying only activates when prints are scheduled, ambient drying keeps filament dry on all idle printers at all times.

How It Works¶

1. The scheduler continuously monitors all idle printers
2. For each AMS unit, it reads the current humidity level
3. If humidity exceeds the Fair (orange) threshold from Settings, drying is triggered — after the sustained-humidity wait, if it is switched on
4. The drying temperature and duration are determined by the loaded filament types using the configured drying presets
5. Drying runs for the preset duration — the printer stops it automatically when the cycle completes

Unlike queue auto-drying, ambient drying does not require any scheduled queue items. It runs whenever a printer is idle and its AMS humidity is above the threshold.

Enabling Ambient Drying¶

1. Go to Settings > Workflow
2. Find the Queue Auto-Drying card
3. Enable Ambient drying

Waiting Out a Humidity Spike¶

Opening the AMS lid can admit room air and cause a temporary humidity rise. Ambient drying uses the unit's effective humidity trigger threshold: the most restrictive applicable per-filament threshold when overrides are configured, or the global AMS Humidity Threshold (Fair) otherwise (see Per-Filament Humidity Threshold). With the sustained wait off, one reading above that threshold can start a cycle. Whether a rise is transient or signals a need for drying depends on the AMS and room conditions.

Require sustained humidity (shown once ambient drying is enabled, in the same settings block) makes an ambient start wait until the unit's humidity has stayed above its effective trigger threshold continuously for a set number of minutes (5–240). The field starts at 15 minutes when you switch it on. Off by default — with it off, ambient drying starts instantly, exactly as before. The wait belongs to ambient drying: with ambient drying off it has no effect, even if a value is still stored.

Continuously means exactly that:

• A single reading back at or below the threshold clears the wait. The clock starts over the next time the reading crosses the threshold.
• A missing reading is treated as no information, not as a dip — a sensor that skips a beat does not reset the count.
• A gap longer than four scheduler polling intervals, with a two-minute minimum (for example, after Bambuddy restarts, the printer disconnects, or a print runs on a printer that is not drying while printing), restarts the wait. Time nobody measured is not evidence the humidity stayed high. The restart is logged, so a wait that never matures can be explained from the log.

Only a printer with a scheduled queue item pending keeps the instant behavior — minutes burned ahead of a scheduled job is exactly what queue auto-drying exists to prevent, and the exemption follows the schedule whether the printer is idle or printing. While ambient drying is on, a start on a printer that is printing (possible with Continue drying while printing) serves the same wait as a start on an idle printer: a lid opened mid-print causes the same brief spike.

Note that the exemption is per printer, not per AMS unit: any pending scheduled item lifts the wait for every AMS on that printer, including units the scheduled job will never touch. A printer that always has something queued — a standing schedule, for instance — effectively never waits; its drying is governed by queue auto-drying's deadline logic instead.

The wait runs alongside the 30-minute cooling-off period after a finished cycle rather than after it, so a re-dry waits for whichever is longer, not both in a row. And like the cooling-off period and the unproductive-cycle suspension, it only ever delays starting a cycle — a running cycle, or one you started by hand, is untouched.

Using Both Modes Together¶

Ambient drying and queue auto-drying can be enabled simultaneously. They complement each other:

When both are enabled and a printer has scheduled prints, queue auto-drying takes precedence (since it is aware of print scheduling and blocking/non-blocking behavior). On printers with no scheduled prints, ambient drying takes over.

Requirements¶

• AMS 2 Pro or AMS-HT unit (original AMS does not support drying)
• Supported printer firmware (see firmware requirements above)
• Humidity above the effective trigger threshold (per-filament override when configured; otherwise the global Fair threshold)
• No active power constraints on the AMS unit (see power supply requirements)

Continue Drying While Printing¶

Bambu shipped an "AMS Print While Drying" firmware feature on selected printers that lets the AMS keep running its drying cycle concurrently with an active print. With this feature enabled in Bambuddy, the existing auto-drying scheduler can also evaluate printers that are mid-print — drying does not stop the instant a print starts. With queue auto-drying or ambient drying also on, a printing printer is dried when its humidity is above the threshold, whether or not it has scheduled prints. The sustained-humidity wait applies to these starts only while ambient drying is on.

Off by default. Opt-in toggle in Settings > Workflow > Queue Auto-Drying > Continue drying while printing.

Firmware Requirements¶

These minimum firmware versions are verified per Bambu wiki release notes (release-note phrasing: "printing while filament is drying" / "Print While Drying"):

Not supported (intentionally excluded — wiki release notes never mention "Print While Drying" for these models):

• P1P / P1S
• A1, A1 Mini
• X1 (non-C), X1E

On an unsupported printer the toggle has no effect — the firmware reports dry_sf_reason=[0] (TaskOccupied) any time a print is running, so any attempt to start drying mid-print is rejected at the printer.

How It Works¶

1. The auto-drying scheduler evaluates all active printers, not just idle ones
2. For each printer, it checks model and firmware against the matrix above
3. If the printer is mid-print and supports concurrent drying and AMS humidity exceeds the threshold, drying starts (or continues) using the conservative per-AMS preset
4. The mid-print drying temperature is automatically capped at max(40, preset_temp - 5) — Bambu's own release notes warn "lower drying temperature during printing" and "drying temperature must not exceed the filament's softening temperature". The 5 °C offset protects spools inside the hot enclosure during an active print
5. Drying runs for the preset duration, just like the idle path — the printer stops it when the cycle completes
6. The firmware's per-AMS dry_sf_reason field continues to arbitrate — if hardware rejects the command for any reason (busy AMS, power constraint, filament at outlet), the scheduler honours that decision per AMS

Enabling¶

1. Go to Settings > Workflow
2. Find Continue drying while printing in the Queue Auto-Drying card
3. Enable the toggle

The toggle is independent of queue auto-drying and ambient drying — you can mix and match. With all three enabled, drying runs in idle gaps and during prints on capable hardware, each cycle running for its configured preset duration.

Safety¶

• Temperature cap — max(40, preset_temp - 5) °C, applied automatically. The user-configured idle preset is not touched; the cap only applies to the mid-print code path
• Firmware is the ultimate arbiter — Bambuddy never sends a drying command that contradicts the printer's reported state. The matrix is a UI affordance; if Bambu silently ships the feature to a new model, Bambuddy will surface the toggle there too on the next release
• Default off — existing installs see no behaviour change until the toggle is enabled

Requirements¶

• Supported printer firmware (matrix above)
• AMS 2 Pro or AMS-HT unit (original AMS does not support drying)
• Humidity above the configured threshold
• No active blocking constraints on the AMS unit (see power supply requirements)

Configurable Drying Presets¶

Customize the drying temperature and duration for each filament type. These presets are used by both manual drying, queue auto-drying, and ambient drying.

Default Presets¶

Defaults are based on BambuStudio's official filament drying profiles:

Editing Presets¶

1. Go to Settings > AMS Display Thresholds
2. Find the Drying Presets table
3. Edit temperature (°C) and duration (hours) for each filament type
4. Changes auto-save

Auto Off After Drying (Smart Plug)¶

If the printer (or its AMS) is on a smart plug, Bambuddy can cut power automatically once a drying cycle completes. The trigger works for all three drying paths — manual drying, queue auto-drying, and ambient drying — because Bambuddy detects completion from the printer's MQTT state (dry_time falling from a positive value to 0), not from how the cycle was started.

Enabling¶

1. Open Settings > Smart Plugs (or expand the plug card on the dashboard)
2. On the plug that powers the printer and AMS, enable Auto Off After Drying
3. Set the Drying delay (minutes) — default 10 minutes, gives the AMS chamber time to cool before power is cut

How It Differs From Print-Finish Auto-Off¶

Both toggles are independent — you can enable either, both, or neither on the same plug.

Full Smart Plug documentation

Historical Charts¶

Click on the humidity or temperature indicator to view historical data:

Time Ranges¶

• 6 hours - Recent trends
• 24 hours - Daily pattern
• 48 hours - Extended view
• 7 days - Weekly overview

Chart Features¶

• Min/Max/Avg statistics
• Threshold reference lines
• Interactive tooltips
• Zoom and pan

Data Retention¶

AMS data is stored for historical analysis:

Default Retention¶

• 30 days of humidity/temperature data
• Configurable in Settings

Configuring Retention¶

1. Go to Settings > General
2. Find AMS Data Retention
3. Set number of days (1-365)
4. Older data is automatically purged

AMS Notifications¶

Get notified about AMS conditions:

Available Alerts¶

Setting Up¶

1. Go to Settings > Notifications
2. Add or edit a provider
3. Enable AMS-related events
4. Save changes

Full notifications guide

AMS-HT vs Standard AMS¶

AMS-HT Temperature Control¶

AMS-HT units can actively dry filament. See Remote AMS Drying for setup and usage.

Custom AMS Labels¶

Assign friendly names to your AMS units to easily identify them in multi-AMS setups.

AMS Info Card¶

Hover over any AMS label (e.g. "AMS-A") on the Printers page to see a popover with:

• Serial Number — The hardware serial from MQTT
• Firmware Version — Parsed from the printer's get_version response
• Friendly Name — An editable text field for your custom label

Setting a Custom Label¶

1. Hover over the AMS label on the Printers page
2. Type a name in the "AMS Name" field (e.g. "Silk Colours", "Workshop AMS")
3. Click Save or press Enter
4. To remove a label, clear the field and save, or click Clear

Label Persistence¶

Labels are stored by AMS serial number, so they persist when the AMS is moved to a different printer. If the AMS serial is not available (older firmware), a fallback key based on printer ID and AMS position is used.

Custom labels also appear in the Inventory page location column alongside the slot identifier, making it easy to find spools across a print farm.

Slot Numbers¶

Each filament color circle now displays a 1-based slot number with automatically inverted text contrast — black text on light filaments, white text on dark filaments.

AMS Discovery¶

Bambuddy automatically discovers connected AMS units:

• Detected during printer connection
• Updates when AMS configuration changes
• No manual configuration needed

Dual-Nozzle Wiring¶

For H2D and other dual-nozzle printers, Bambuddy displays the AMS wiring configuration:

• Which AMS units feed which nozzle
• Visual diagram of connections
• Helps plan multi-material prints

Nozzle-Aware Filament Mapping¶

On dual-nozzle printers (H2D, H2D Pro), each AMS unit is physically connected to either the left or right nozzle. The 3MF file's nozzle assignment is used to pre-fill the right slot per filament; you can still manually override with a tray on the other extruder when you've intentionally loaded the required filament there.

Auto-match (pre-fill behaviour):

1. The 3MF file contains filament_nozzle_map and physical_extruder_map in project_settings.config, mapping each filament slot to a target nozzle (0 = right, 1 = left)
2. The printer reports ams_extruder_map via MQTT, indicating which AMS unit feeds which nozzle
3. Auto-match prefers trays on the slicer-assigned nozzle when matching by type + colour
4. If no matching tray exists on the target nozzle, auto-match falls back to the full tray list

Manual cross-extruder picks:

The per-filament slot dropdown in the Print modal shows every loaded AMS slot, regardless of which extruder it feeds. The L / R badge stays next to each filament as a hint to the slicer's intent, but it does not hide slots on the other extruder. If you've loaded the required filament into an AMS on the "wrong" side on purpose (a common H2D workflow when one AMS is busy with another colour set), you can pick it.

The printer's firmware decides at start-print whether the resulting ams_mapping is physically valid; if a cross-extruder combination really can't be served, the firmware reports the error normally.

This applies to:

• Print scheduler — automatic filament matching for queued prints (still nozzle-preferring; never picks cross-extruder on its own)
• Print modal — filament mapping for ASAP, Queue, Schedule, and Manual Start dispatch options
• Multi-printer selection — per-printer mapping for print farms

Filament Track Switch (FTS) Support¶

The Filament Track Switch is an external accessory for dual-nozzle printers that sits between an AMS and the printer's extruders, dynamically routing any AMS slot to either nozzle. With the FTS installed, the AMS is no longer wired to a single extruder — it can feed either one through the track switch.

When Bambuddy detects the FTS (via print.device.fila_switch in the printer's MQTT push), the per-nozzle filter is automatically suppressed in the print modal:

• Without FTS — each AMS unit feeds a fixed nozzle, so the dropdown only shows trays on the matching nozzle (preventing the "position of left hotend is abnormal" failure that comes from cross-nozzle assignment).
• With FTS installed — every loaded AMS slot is selectable for any nozzle's filament, since the FTS handles the routing on the fly.

Inlet badges¶

The switch has two filament inlets (In-A, In-B) and two outlets, and can pair any inlet with any outlet. Each AMS is plumbed into one inlet, which you assign on the printer's own Manual AMS Setup screen — several AMS units can share an inlet through a 4-in-1 PTFE adapter.

That inlet is what Bambuddy shows, lettered L for In-A and R for In-B:

• On the printer card, each AMS carries an L or R badge in a distinct colour from the plain nozzle badge, and its tooltip names the inlet in full — Filament Track Switch IN-A (L) — feeds both nozzles.
• In the print dialog, each slot in the dropdown is labelled [L] or [R].

An AMS that still reports a fixed nozzle keeps its ordinary L/R badge. A switch that has been fitted but not yet assigned on the printer screen shows no badge at all, rather than a guess.

K-profiles and the switch¶

Flow-dynamics (K) profiles are calibrated per nozzle — the same spool can read K=0.018 on the left hotend and K=0.020 on the right — and the printer numbers its calibration table per nozzle too, so index 16 exists on both and means a different profile on each. An AMS tray holds exactly one index.

That makes moving an AMS between inlets a calibration change as well as a routing one. Bambuddy handles it:

• Configure Slot offers the profiles for the nozzle that slot actually feeds, names the hotend on each option, and resolves the slot's current index against its own nozzle. The other hotend's profiles stay available under Other K profiles if you want to override.
• Moving an AMS to the other inlet re-selects each configured slot's counterpart profile for the new nozzle, provided the spool has one. A slot Bambuddy doesn't know, or a spool calibrated on one hotend only, is left as you set it.

Loading and unloading through the switch¶

Without the switch, each AMS is wired to one nozzle and the printer works out where a load is going by itself. With the switch fitted that stops being true: an AMS is bound to an inlet, both nozzles are reachable from every slot, and a load that names neither gives the firmware nothing to act on — it is discarded without a word.

So Load on a slot asks first, exactly as Bambu Studio does:

• Both nozzles are offered, with neither preselected, so a stray Enter cannot feed the wrong one.
• The nozzle already fed from that very slot is greyed out — it is already there.
• If any AMS is still unassigned to an inlet, the load is refused before anything is sent, with a note to finish Manual AMS Setup on the printer.

Unload does not ask. The printer reports which slot each hotend is currently fed from, so Bambuddy retracts the one holding the slot whose menu you used. A slot no hotend is holding is reported as such rather than unloading something else.

Same-inlet warning¶

If every filament a print needs sits behind the same inlet, the print dialog says so. This is legal but slow: swapping between two filaments on one inlet means retracting the outgoing spool all the way back to its AMS before the next can be fed up the shared tube, where a swap across the two inlets only retracts as far as the switch. Moving one spool to an AMS on the other inlet is usually all it takes.

Spoolman Integration¶

Sync AMS slots with Spoolman for complete filament tracking:

1. Configure Spoolman integration in Settings
2. AMS slots sync automatically
3. Track usage across your inventory

Spoolman integration guide

Tips¶