Bambu P1S vs A1: specs, material support, and which one to buy

Bambu Lab launched in 2022 and quickly became one of the most-discussed names in desktop 3D printing. Their printers arrive largely pre-assembled, pair with capable slicer software, and are designed to work well out of the box with less manual tuning than most competitors. The P1S and A1 sit in different parts of the range and suit different use cases. Understanding the distinction will save you money — or a purchase you later regret.

What is the Bambu P1S?

The P1S is an enclosed CoreXY printer. In a CoreXY design, the print head moves in both the X and Y axes while the build plate descends in Z only. This gives a rigid, fast motion system that handles acceleration well and keeps dimensional accuracy consistent across the full build volume. The sealed enclosure traps heat around the print, which is the single most important feature for printing engineering-grade filaments.

Key specifications:

• Build volume: 256 × 256 × 256 mm
• Maximum advertised speed: 500 mm/s (250–300 mm/s is more realistic for quality output)
• Fully enclosed with an active carbon filter
• Compatible with Bambu's full AMS (Automatic Material System); up to 16 colours via four linked AMS units
• Supported materials: PLA, PETG, TPU, ABS, ASA, Nylon, Polycarbonate, and carbon-fibre or glass-filled composites
• Lidar-assisted first-layer calibration, input shaping (vibration compensation), and a built-in camera

The enclosure and active carbon filter make the P1S the safer choice if you are printing ABS or ASA in a room people use regularly, as those materials emit volatile compounds during printing. The lidar scan on the first layer checks that the initial traces are adhering correctly and can flag a problem before a long print fails at the outset.

What is the Bambu A1?

The A1 is an open-frame bed-slinger. The build plate moves in the Y axis (forward and backward), the toolhead moves in X, and the Z axis lifts the gantry. This is a simpler and more cost-effective mechanism than CoreXY. Bambu has tuned the A1 well: it produces good results with PLA and PETG at speeds that outpace most traditional printers in the same class.

Key specifications:

• Build volume: 256 × 256 × 256 mm
• Maximum advertised speed: 500 mm/s
• Open frame, no enclosure or heated chamber
• Compatible with AMS Lite — 4 colours from a single unit; not expandable to 16 colours
• Supported materials: PLA, PETG, TPU, and other filaments that do not require a controlled ambient temperature

The A1 is not designed to print ABS, ASA, Nylon, or Polycarbonate. Without an enclosure, those materials cool unevenly, causing layer delamination and warped parts. Attempting them on an open-frame machine in a normal room leads to wasted filament rather than usable prints. If your project requires heat-resistant or chemically resistant materials, the A1 is the wrong tool.

Key differences

Enclosure and material support

This is the practical heart of the comparison. If you only ever print PLA and PETG — which covers the majority of hobby, household, and prototyping use cases — an enclosure adds cost without adding meaningful benefit. If you need ABS for automotive or high-temperature applications, ASA for outdoor parts that must withstand sunlight and rain, Nylon for wear-resistant components, or Polycarbonate for structural work, the P1S is the only sensible choice between these two machines.

Multi-colour system

Both printers support multi-colour printing, but the systems differ in scope. The P1S uses Bambu's full AMS, which can be chained up to four units for 16-colour prints. The A1 uses AMS Lite, which handles 4 colours from a single unit and cannot be expanded further. AMS Lite is also somewhat more prone to jams with difficult materials — very flexible TPU and brittle Silk PLA are the common culprits — compared to the full AMS.

Speed in practice

Both printers advertise the same 500 mm/s ceiling, but a meaningful speed comparison depends on material, geometry, and layer height. A well-calibrated A1 printing PLA will be close in print time to a P1S printing the same file. The P1S shows a clearer advantage on engineering materials, complex tall geometries, and long overnight prints, where its CoreXY kinematics maintain accuracy better than a bed-slinger at sustained high speeds.

Slicer and connectivity

Both machines are designed around Bambu Studio, which is based on PrusaSlicer and includes Bambu-specific profiles, AMS calibration, and optional cloud print management. Orca Slicer — an open-source fork with additional tuning options — also supports both printers and is widely used. Neither machine is locked to Bambu Studio, though some AMS features work most reliably within it. Both printers support Wi-Fi, LAN, and remote monitoring via the Bambu Handy app. LAN-only mode (no cloud connection) is available on both, which matters if you are printing on a private network.

Which should you buy?

The A1 suits you if:

• PLA and PETG cover your material requirements
• Budget is the primary constraint
• You want a straightforward, well-supported printer for hobby or household use
• 4-colour multi-material output is sufficient for your projects

The P1S suits you if:

• You need ABS, ASA, Nylon, Polycarbonate, or filled composites
• You want to expand to 16-colour printing in future
• You print in a cold or draughty space where open-frame printers struggle to hold temperature
• You run high volumes or professional work where reduced print failures justify the premium

Neither machine is a poor choice in its category. The A1 is one of the better open-frame printers available at its price point. The P1S is a capable enclosed CoreXY that competes well against machines at similar and higher prices. The decision reduces to a single question: what materials do you need to print?

Common issues to be aware of

AMS and AMS Lite jams are the most frequently reported problem with both printers. Humid filament is the root cause in the majority of cases. Storing filament in sealed containers with silica gel and using a dry box during printing largely prevents moisture-related jams. Brittle Silk PLA and very soft TPU are also prone to breaking or tangling inside the buffer tubes.

Hotend clogs: the standard hardened-steel nozzle handles most materials well, but carbon-fibre and glass-filled filaments are abrasive. Check nozzle wear periodically if you print composites regularly, and replace before it affects print quality rather than after.

Bed adhesion: the textured PEI build plates lose grip gradually with use. Washing the plate with warm soapy water every few sessions restores adhesion reliably. Avoid touching the print surface with bare hands, as skin oils reduce bonding.

Firmware updates: Bambu pushes updates regularly via the app. Most are improvements, but it is worth reading the release notes on the Bambu community forum before updating a machine that is mid-production or working reliably. Occasionally an update introduces a regression that is patched in the following release.

Warranty: fitting unofficial nozzles, modifying firmware, or using third-party AMS-bypass hardware may affect your warranty. Both machines have active modding communities; weigh this against warranty coverage before making changes to a machine still within its warranty period.

When to mail it in

Intermittent faults — extruder clicking under load, repeated heat-creep clogs after a nozzle swap, a heated bed reporting inconsistent temperatures, or an electrical fault on the main board — are often faster to diagnose properly on a bench with a multimeter and thermal camera than by working through parts at random. If your Bambu A1 or P1S has developed a fault you cannot resolve through the usual troubleshooting steps, Hark Tech offers mail-in 3D printer repair for both machines. A diagnostic assessment is provided before any work is quoted, so you know the likely cost before committing. Get in touch via the contact page to describe what the machine is doing.