Bambu P1S Nozzle: Stainless vs Hardened Steel
The Bambu P1S ships with a 0.4 mm stainless-steel nozzle, not hardened steel. This guide explains when a hardened-steel P1-series hotend is worthwhile, which nozzle diameter suits the job and how to follow Bambu's safe replacement process.
The Bambu P1S ships with a 0.4 mm stainless-steel nozzle. Hardened steel is an optional upgrade, not the factory-fitted nozzle. That distinction matters when you choose abrasive filament or order a replacement hotend.
This guide uses Bambu Lab's current P1S specification and P1-series maintenance instructions. It focuses on the practical choice between stainless and hardened steel without treating a P1S hotend like a generic threaded nozzle.
What comes fitted to the P1S
Bambu's P1S specification lists:
- Nozzle material: stainless steel
- Included diameter: 0.4 mm
- Optional diameters: 0.2 mm, 0.6 mm and 0.8 mm
- Maximum hotend temperature: 300 °C
The official specification is available in the Bambu Lab P1S unboxing and specification guide.
Stainless steel or hardened steel?
Keep the standard stainless-steel nozzle for ordinary, non-abrasive filament when it is producing consistent extrusion and the diameter suits the part. There is no SEO-friendly shortcut here: a working standard nozzle does not need replacing just because a hardened option exists.
Choose a compatible hardened-steel P1-series hotend before regularly printing abrasive filament such as carbon-fibre-filled, glass-fibre-filled or glow-in-the-dark material. Abrasive particles gradually enlarge and distort a softer nozzle orifice, which can make line width and flow inconsistent.
Hardened steel is about wear resistance. It does not automatically improve the surface finish, dimensional accuracy or strength of an ordinary PLA or PETG print.
Which nozzle diameter should you use?
0.2 mm prioritises fine detail, with longer print times and a narrower flow path.
0.4 mm is the standard general-purpose size and the nozzle supplied with the P1S.
0.6 mm trades some fine detail for wider extrusion lines and is a practical option for larger functional parts.
0.8 mm is aimed at large parts and high material flow where fine surface detail is not the priority.
After fitting a different diameter, select the matching nozzle size in the printer and slicer configuration before printing. A profile prepared for 0.4 mm is not a safe substitute for a 0.6 or 0.8 mm configuration.
Buy the correct P1-series part
The P1S uses a P1-series hotend. Check that the replacement is explicitly listed for the Bambu P1 series and that its material and diameter match the job.
Do not follow a generic V6, MK8 or Volcano nozzle guide. In Bambu's official P1-series process, the hotend is removed from the toolhead after the printer is powered off and cooled. It is not hot-tightened into the machine like a conventional threaded nozzle.
Safe replacement outline
Bambu's official process says to unload the filament, let the nozzle cool below 50 °C, switch the printer off and disconnect power before maintenance. The toolhead cover and fan connector are removed, followed by two hotend mounting screws. After refitting, Bambu instructs the user to run the printer's calibration process.
Use the full Bambu Lab P1-series complete hotend replacement guide while carrying out the work. The illustrated sequence and current safety notes are more useful than a shortened third-party step list.
Signs that a nozzle may be worn
Nozzle wear is normally gradual. Possible signs include:
- line width becoming inconsistent after flow calibration;
- extrusion quality declining progressively rather than failing suddenly;
- a visibly enlarged or misshapen nozzle opening; or
- abrasive filament use followed by persistent dimensional or surface changes.
Rule out a partial clog, wet filament, damaged extruder components and an unsuitable profile before assuming the nozzle material is the only cause.
When a print service is the simpler route
If you need one part in an abrasive engineering material but do not want to buy and fit another hotend for a single job, upload the file to Hark Tech's UK 3D printing service. The file is checked against the selected material and the price is shown before checkout.
Sources checked
Sources checked 27 August 2026.