Bambu has confirmed a 2.85 mm filament for the H3C and a feed system called FlexFeed. It has not confirmed a price, or said whether the H3C still takes 1.75 mm. Everything else here is a leak or my own reasoning, labeled as such.
The page with real numbers is not the main teaser. It is a listing for "TPU 75A for H3C", live on Bambu's EU store but not surfaced on the main site. I treat it as the first hard filament spec, because the copy is Bambu's own.
| Spec | What Bambu says | Status |
|---|---|---|
| Filament diameter | 2.85 mm | CONFIRMED |
| Diameter tolerance | ±0.05 mm | CONFIRMED |
| Feed system | FlexFeed. The page binds the two: "2.85 mm — FlexFeed, reliable printing" | CONFIRMED |
| Rated flow | 10 mm³/s, about three times a conventional setup | CONFIRMED |
| Hardness | 75A, the softest TPU Bambu has made | CONFIRMED |
| Intended use | Wearables, skin-contact certified, natural matte finish | CONFIRMED |
| Compatibility | "Compatible only with H3C" | CONFIRMED |
| Spool size | 1 kg, several colors | CONFIRMED |
| On sale | November 3 | CONFIRMED |
Two confirmed items sit outside the table. The third teaser, "TPU 75A: Our softest yet, for Shore", says TPU 75A and TPU 90A can be finished in the same print. The second, "Introducing…Your print", carries "Tool Changer. Game Changer." and shows a tool head lifting clear of the print.
On hardware Bambu stays thin: "nine tools, built into one printer, a new tech to swap". The launch event is November 3 at 9:00 AM EST. Every Bambu printer sold today runs 1.75 mm, which makes 2.85 mm a break rather than a tweak.
The usual engineering argument for a thicker strand is buckling. Soft filament is a column in compression between the drive gear and the melt zone. At 1.75 mm it is thin, and at 75A soft enough to fold sideways before it reaches the hotend. A 2.85 mm strand of the same hardness has more cross-section and bends less, so a short path can push it with less support hardware.
The second argument is throughput. Volume per second scales with cross-section, so a thicker strand moves more material per unit of feed, which is roughly what 10 mm³/s and "about three times" imply. That is arithmetic, not proof: the gain could come from the filament, a longer melt zone, or a shorter path, and Bambu has published none of the three.
The physical part first. A 1.75 mm strand will not run in a 2.85 mm path. The bore, drive gap, and grip are sized for the larger strand, so a thinner one has nothing to push against. That is geometry, not policy.
The policy part is thin. Whether the H3C keeps any 1.75 mm route — a second path, a convertible hotend, one or two tools for the old standard — is UNKNOWN. If all nine are 2.85 mm, a current owner starts a second material library: spools, profiles, calibration. The lock also runs both ways. The TPU 75A page says H3C only, so it will not go into an H2D or an X1C either.
Nine tools is confirmed. Whether all nine share the same filament story is not. What follows comes from forum photos and a leaked assembly drawing.
Six things stay unknown: whether all nine tools run 2.85 mm or a mix of 1.75 and 2.85 UNKNOWN, whether the storage is 7 slots or 10 UNKNOWN, whether the top unit sits against the heated chamber and softens TPU at the feeder UNKNOWN, whether a 2.85 mm abrasive or engineering blend exists UNKNOWN, the spool's inner and outer diameter and whether it fits the existing AMS UNKNOWN, and whether a swap replaces the whole toolhead or only the nozzle UNKNOWN.
UNKNOWN Nobody has said either way. A 1.75 mm strand cannot run in a 2.85 mm channel, so the answer depends on a second route existing, and I would not assume it does.
No. The page says compatible only with H3C, and every current Bambu printer runs 1.75 mm. That is Bambu's wording, not an interpretation.
There is no price for the spool and none for the printer. I will not guess one.
On sale November 3, the same day as the 9:00 AM EST event. That is the date Bambu has published. China pricing and timing are UNKNOWN.