Bambu Lab Nozzle Guide:
Stock, Hardened Steel, CHF & Ruby

The Short Answer

If you only print PLA, PETG, ABS, or TPU without any fiber-filled or abrasive additives, the stock brass nozzle on your Bambu Lab printer is the right tool for the job — leave it alone. Brass has the best thermal conductivity of any common nozzle material, which means faster, more consistent heating and slightly better extrusion at high flow rates.

The moment you load a filament with carbon fiber, glass fiber, glow-in-the-dark particles, metal powder, or any other "filled" additive, that abrasive material acts like fine sandpaper running through the nozzle orifice thousands of times per print. Brass is soft, and the orifice will visibly enlarge — sometimes within a single spool — leading to under-extrusion, dimensional drift, and blobbing as the hole goes out of round.

That's the entire decision tree in one sentence: plain filaments → stock brass. Abrasive filaments → hardened steel, CHF, or ruby. The rest of this guide is about which of those three to pick, plus stainless steel for the food-contact and corrosion-resistance crowd.

The Stock Brass Nozzle

Every Bambu Lab printer — X1C, P1S, A1, A1 Mini, and the H2 series — ships with a brass nozzle as the default. Brass is a copper-zinc alloy, and copper's thermal conductivity is roughly eight times higher than hardened steel's. In practice, that means the nozzle tip recovers temperature faster after a retraction or a fast direction change, which translates to fewer under-extruded sections on detailed, high-speed prints.

Brass is also soft and easy to machine precisely, which is why it's the default for nearly every FDM printer on the market, not just Bambu's. The tradeoff is wear: brass is roughly as hard as a coin, and an abrasive filament will erode the orifice noticeably after as little as 100–500g of filament, depending on how aggressive the additive is.

Hardened Steel Nozzles

Hardened steel nozzles are machined from tool steel and heat-treated to a much higher hardness than brass — typically rated around 60+ on the Rockwell C scale, versus brass's much softer rating. This makes them dramatically more resistant to the sanding effect of fiber-filled filaments, often lasting 10–20x longer than brass under the same abrasive load.

The catch is thermal conductivity. Standard hardened steel conducts heat far worse than brass, which on a high-flow printer like the X1C or P1S can show up as mild under-extrusion at the print speeds Bambu Lab printers are tuned for, particularly with high-flow-rate profiles. For many users this is barely noticeable; for others running near-maximum speeds, it's enough to warrant a small flow-rate or temperature tweak in OrcaSlicer.

Standard hardened steel nozzles are inexpensive and widely available in 0.2–0.8mm sizes, making them a reasonable default if you print fiber-filled filament only occasionally and don't want to swap nozzles back and forth constantly.

Hardened Steel CHF (High-Flow)

CHF — Coated Hardened Flow — is Bambu Lab's own high-flow hardened steel nozzle, designed specifically to close the thermal gap that standard hardened steel has against brass. It uses the same hardened tool steel for abrasion resistance, but pairs it with a wider internal flow channel geometry and a coating on the interior surface that improves heat transfer to the melt.

The result is a nozzle that holds up to carbon fiber and glass fiber filaments like a standard hardened steel nozzle, but extrudes at flow rates much closer to brass — Bambu markets these as supporting significantly higher max flow rates than its standard hardened steel nozzles, which matters if you run fast profiles on the X1C, P1S, or H2D.

The downside is price — CHF nozzles cost roughly double a standard hardened steel nozzle. For frequent fiber-filled printing on a high-flow Bambu printer, that premium is usually worth it; for occasional use, standard hardened steel is adequate.

Stainless Steel Nozzles

Stainless steel sits in a different lane from the abrasion-focused options above. Its main selling points are corrosion resistance and the absence of the small amount of lead sometimes present in brass alloys, which makes it the common choice for food-contact or medical-adjacent prints.

Abrasion resistance on stainless is moderate — better than brass, generally not as good as properly hardened tool steel — and thermal conductivity sits in the middle of the pack as well. Stainless nozzles are a reasonable all-rounder if your priority is corrosion resistance (for example, printing with filaments that release corrosive fumes or residues) rather than maximum wear life against fiber-filled materials.

Ruby-Tipped Nozzles

Ruby-tipped nozzles use a synthetic ruby insert at the orifice — typically set into a brass or steel body — giving you a wear surface that's harder than hardened steel and chemically inert. They resist both mechanical abrasion from fiber-filled filaments and chemical attack from corrosive or reactive materials, and they tend to retain the brass body's better thermal performance compared to solid hardened steel.

The tradeoff is cost: ruby nozzles typically run several times the price of a CHF nozzle. They make the most sense if you're printing abrasive composites essentially every day — a small business running carbon-fiber nylon parts continuously, for example — where the extended lifespan pays for the price difference over time. For a hobbyist who runs the occasional CF or glow-filament spool, a hardened steel or CHF nozzle gets you most of the benefit for a fraction of the cost.

Nozzle Sizes for Bambu Lab Printers

Independent of material, Bambu Lab's quick-swap hotend systems across the X1, P1, A1, and H2 series support a standard range of nozzle diameters:

• 0.2mm — fine detail, miniatures, small text. Slow, prone to clogging with anything but well-dried filament.
• 0.4mm — the stock default and the right choice for the vast majority of prints. Best balance of detail, speed, and reliability.
• 0.6mm — faster prints with thicker layers, useful for larger functional parts where surface detail matters less than print time.
• 0.8mm — fastest layer-time option, best for big, simple parts, vase-mode prints, or draft-quality prototypes.

Switching nozzle size requires updating the nozzle diameter in your slicer profile (OrcaSlicer reads this from the printer's installed nozzle when connected, or it can be set manually) — print settings like line width, flow, and supported layer heights all scale with nozzle diameter. If you haven't dialed in your slicer settings for your current nozzle yet, our OrcaSlicer Settings Guide for Bambu Lab covers the settings that matter most.

Swapping and Maintaining Nozzles

Bambu Lab's hotend design across the X1, P1, A1, and H2 series uses a quick-swap nozzle module rather than the traditional "unscrew a brass nozzle from a hot block" approach used on many older printers. Swapping a nozzle means removing and replacing the nozzle module — Bambu's official guides cover the exact procedure per printer, and it typically takes a few minutes with the printer at or near operating temperature.

A few practical habits extend nozzle life regardless of material:

• Dedicate a nozzle to abrasive filaments if you switch between plain and fiber-filled materials often — keeping a hardened steel or CHF nozzle installed only when running abrasive spools avoids unnecessary wear cycles on your brass nozzle.
• Dry abrasive filaments properly. Damp fiber-filled filament prints worse and can accelerate wear through inconsistent extrusion. See our How to Dry Filament guide for temps and times.
• Check the orifice periodically on heavily-used nozzles — an enlarged or oval orifice shows up as inconsistent extrusion width and is the clearest sign it's time to swap.
• Cold-pull or clean before storage if you're swapping a nozzle out, to avoid leaving degraded filament inside that can clog it next time it's used.