What the Bambu Lab Filament Track Switch does

Bambu Lab's Filament Track Switch sits between your AMS units and a dual-nozzle printer, so the AMS is no longer tied to one nozzle. Here is what it changes, which printers and firmware it needs, how it goes in, and what it cannot feed.

A filament track switch module is a small Bambu Lab box that lets any AMS slot feed either nozzle of a dual-nozzle printer: the X2D, H2D or H2C. Without it, each AMS (Bambu Lab’s Automatic Material System spool changer) feeds only one fixed nozzle. Bambu Lab’s US store listed it at $59.99 on 2026-10-12.

What is a filament track switch?

The Filament Track Switch is a Bambu Lab accessory for dual-nozzle printers that sits between the AMS units and the printer. It has two filament inlets and two outlets, and an electromagnet flips an internal guide so filament from either inlet can reach either nozzle. That removes the fixed pairing of each AMS to one nozzle.

Inside, each inlet has a position sensor that tells the printer which AMS is connected. When the feed path has to change, an electromagnet module moves a magnet, and a guide pointer on its back steers the filament into the other outlet. That gives four paths: In-A to Out-A, In-A to Out-B, In-B to Out-A and In-B to Out-B.

Which printers does the Filament Track Switch work with?

Bambu Lab’s store lists the X2D, H2D and H2C as compatible. Bambu Lab’s wiki has one setup guide for the X2D and one for the H2 series, and it gives the minimum software for each:

Printer	Printer firmware	Bambu Studio	Bambu Handy
X2D	01.01.00.00 or later	2.5.3 or later	Not listed
H2C	01.01.50.00 beta or later	2.5.3.60 or later	3.18.0 or later
H2D	01.04.00.00 or later	2.8.1.55 or later	3.24.0 or later

Update the printer before you install the switch. Bambu Lab says more models are being adapted, so check the firmware release notes for other printers. The single-nozzle H2S is not on the list.

What changes when you install it?

The AMS stops being bound to one nozzle. On a stock dual-nozzle printer, the left nozzle draws only from the left AMS and the right nozzle only from the right. With the switch, every spool in every AMS can go to either nozzle.

Situation	Without the switch	With the switch
Filament is in the “wrong” AMS for the nozzle Bambu Studio picked	Move the spool or swap PTFE (Teflon) feed tubes by hand	The switch routes it to the right nozzle
Unattended print in Filament-Saving mode	Switch to Convenience or Custom grouping, which purges more	Filament-Saving grouping works without moving spools
One AMS connected	The other nozzle has no AMS and takes only an external spool	One AMS feeds both nozzles, one at a time
A filament’s nozzle during the print	Fixed before slicing	Can change between height ranges (dynamic mapping)

On a stock machine, assigning filament to the left or right nozzle means matching the slicer’s grouping to the spools in each AMS. With the switch, Bambu Studio can also move a filament to the other nozzle partway through a print. The H2D dual nozzle page shows how the stock grouping works on that printer.

Can one AMS feed both nozzles?

Yes, but only one nozzle at a time. With a single AMS on the switch, the left and right nozzles take turns. Before the other nozzle can load, the AMS pulls the filament all the way back and then feeds the new one. To wire it, plug the AMS into either inlet and run the two outlets to the printer’s two inlets.

The number of AMS units does not change with the switch. The X2D and the H2 series each take up to 4 AMS 2 Pro and 8 AMS HT units: 12 units and 24 slots in all. Bambu Lab strongly advises against the 4-in-1 PTFE adapter with only two AMS units, because the adapter adds feed resistance. Beyond two units, the X2D uses the white 4-in-1 PTFE adapter and the H2 series uses the black H2C-specific 4-in-1 PTFE adapter II. The two are not interchangeable.

How much does it cost and what is in the box?

Bambu Lab’s US store listed the Filament Track Switch at $59.99 USD on 2026-10-12. The box holds:

Item	Quantity
Filament Track Switch	1
6-pin cable	1
PTFE tube, 700 mm	2
PTFE tube, 400 mm	2
ST3×10 screws	4
BT2×8 screws	2

Bambu Lab’s guides also call for two more 6-pin cables, H1.5 and H2.0 Allen keys, and a holder you print yourself from the MakerWorld model linked in each guide. The same model set includes AMS mounting holders, AMS tube guides and two pneumatic connector locking tabs. If the printer runs high-temperature filament, Bambu Lab suggests printing the holder in a heat-resistant material such as PC (polycarbonate), so it does not deform.

How do you install the Filament Track Switch?

The steps below follow Bambu Lab’s H2 series guide for two AMS 2 Pro units. The X2D guide differs where noted.

Update the firmware. Bring the printer, Bambu Studio and Bambu Handy up to the versions in the table above.
Mount the switch. Screw the switch to its printed holder with the two BT2×8 screws and an H1.5 key. Remove the two screws from the printer’s rear panel and fix the holder there with two ST3×10 screws and an H2.0 key. On the X2D, leave the BT2×8 screws loose until the holder is on the panel, then tighten them.
Run the outlet tubes. Fit a 400 mm PTFE tube from each printer filament inlet to a switch outlet. Put a locking tab on each, slid against the outlet. On the X2D, cut two 115 mm tubes instead and run them to the filament buffer. The order of outlets and inlets does not matter.
Run the AMS tubes. Clip a mounting holder and tube guide to each AMS. Run a 700 mm tube from one AMS to a switch inlet, and from the second AMS to the other inlet, each with a locking tab. Keep the tubes as short as feeding allows, at no more than 700 mm from AMS to switch.
Connect the cables. H2 series: switch to printer, AMS to switch, then AMS to AMS. X2D: one AMS to the filament buffer, then the switch to each AMS.
Pair each AMS to an inlet. On the printer screen, open the Filament page and tap the prompt in the lower-left corner. In Auto Mode, load at least one spool in every AMS and unload anything already fed; the inlet sensors then work out which inlet each AMS uses. In Manual Mode, tap each AMS and assign it inlet A or B. Use Manual Mode when an AMS is empty.
Load filament. Tap a filament and choose the left or right nozzle. On the first load, the printer tries the switch’s current position. If three tries fail to reach the chosen nozzle, it retracts and flips the switch before trying again. Once a load succeeds, it saves that mapping for later loads.

Once filament has reached the extruder, the AMS icon turns grey and you cannot change its inlet pairing.

How do you turn on dynamic mapping in Bambu Studio?

On the Prepare page, click the Edit Filament Grouping icon. Select Fila Saving mode, tick Enable Smart Filament Assign at the bottom and click OK. Then slice and print. “L R” next to a filament in the nozzle mapping list means both nozzles will print it at different points in the job.

After slicing, Bambu Studio suggests which filaments go in which AMS. Follow it, because swap speed depends on the inlet:

Different inlets: the old filament only retracts into the switch while the new one feeds from the other inlet. This is the fast path.
Same inlet: the old filament has to go all the way back to the AMS before the new one can feed. This is the slow path.

Bambu Studio puts the two filaments that swap most often on different inlets. Its time estimate assumes the fast path. If you ignore the suggested arrangement, the print can run well past the estimate.

Bambu Lab says dynamic mapping gains most on models whose colors change by height, colors that appear in only small areas, and long jobs with many changes. A model that uses the same colors on every layer, or only 2 to 3 colors, gains little. How much filament dual-nozzle printing wastes has the purge figures.

What can’t you use with the Filament Track Switch?

The switch only carries filament from an AMS, and it adds feed resistance. Bambu Lab’s guides list these limits:

Filaments not meant for the AMS. The X2D guide says not to run TPU (flexible thermoplastic polyurethane), PA6-CF/GF, PET-CF/GF, PPA-CF/GF, PPS-CF/GF or PLA Glow through it. For a TPU job, see printing TPU and PETG in one print.
Filaments sensitive to feed resistance. PLA-CF, PLA Glow and PLA Silk may fail to load or unload. If one fails, move it to another AMS slot, use the recommended tube lengths, or turn the switch off for that job.
External spools. An external spool would permanently occupy one extruder channel, so printing from an external spool means removing the switch first.
High-precision nozzle offset calibration. Neither the X2D nor the H2 series can run it with the switch fitted. Remove the switch, calibrate, then refit it. Bambu Lab says a firmware update will fix this. Dual-nozzle offset calibration covers when you need it.

What if filament jams at the switch?

If filament sticks at a switch outlet, reseat the PTFE tube between the switch and the printer’s buffer. Fit the pneumatic connector locking tab on that outlet, or replace the tube. For a clog inside the switch body, Bambu Lab’s disassembly and troubleshooting guide shows how to open it and clear the path.