Best Anycubic Kobra S1 Mods: Nozzle, Cooling, ACE Pro, Klipper

The Anycubic Kobra S1 is an enclosed CoreXY printer with a direct drive, a 250×250×250 mm build volume, a 320 °C hotend and speeds up to 600 mm/s — and, in the Combo, the 4-spool ACE Pro multicolor unit. The hardware is great for ~$349, but the stock software and a few rough edges hold it back. Here are 20 real mods, from swapping the build surface to running Klipper via Rinkhals. If something already misbehaves out of the box, start with our Kobra S1 known issues, and for the big picture read the Kobra S1 review.

1. BIQU Panda CryoGrip Pro flex plate

The stock Kobra S1 plates work, but many owners want stronger cold adhesion and easier release of big parts. The BIQU Panda CryoGrip Pro is a double-sided spring steel plate with a porous oleophobic coating: PLA sticks at just 30–50 °C, PETG at 50–75 °C, and parts pop off once cooled. Less warping on large models, and no glue. For first-layer adhesion in general, see our first layer guide.

• Glue-free adhesion at low temps — saves energy and preheat time
• Easy release: flex the plate and the part pops off
• Double-sided, matches the Kobra S1 bed size

Difficulty: easy (just sits on the magnetic bed). Compatibility: Kobra S1 / Kobra 3 / Kobra X. Re-calibrate Z-offset after swapping plates.

2. Swappable build surfaces for the job

No single plate is perfect for everything. Many keep 2–3 surfaces on hand: textured PEI (matte bottom, grippy for ABS/ASA), a Cool Plate for PLA/PETG, and a carbon/PET plate for wear resistance with abrasives. Matching the surface to the material fixes half of your adhesion headaches without touching settings.

• Textured — nice matte bottom and grip for ABS/ASA
• Cool Plate — quick PLA/PETG release
• Carbon/PET — lasts longer under CF filaments

Difficulty: easy. Compatibility: Kobra X / S1 / Kobra 3. Keep a separate Z-offset profile per plate.

3. Hardened 0.4 mm nozzle for abrasives

The stock brass nozzle wears out in dozens of hours with abrasives — CF filaments, glow-in-the-dark PLA, wood/metal-filled. A hardened steel 0.4 mm nozzle lasts about 10× longer and handles up to 320 °C. Kits (Innocube3D, HzdaDeve and others) start around $21 and drop in — the S1 hotend is quick-swap. For clogs and nozzle care, see our nozzle clogging guide.

• Roughly 10× the life of brass on abrasives
• Handles engineering materials up to 320 °C
• Quick-swap install, often bundled with silicone socks

Difficulty: medium. Price: from ~$21. Re-run flow and Z-offset after the swap. Note: for the S1 buy versions labeled 'for Kobra S1/Combo' — the hotend is proprietary.

4. Bimetal all-metal heatbreak up to 320 °C

For reliable ABS, ASA, PC and nylon you want an all-metal path with no PTFE in the hot zone. A bimetal heatbreak removes heat creep and PTFE degradation at high temps. Reality-check: there are no classic Bondtech, BIQU or Funssor drop-ins for the S1 hotend — the assembly is proprietary and integrated. The real upgrades are Anycubic OEM parts and compatible clones, not 'just fit a Bondtech.'

• All-metal throat — no PTFE in the heat zone
• Stable ABS/ASA/PC/nylon up to 320 °C
• Fewer heat-creep clogs on long prints

Difficulty: medium/advanced. Compatibility: Kobra S1. Re-tune PID and flow after installation.

5. Ceramic 48 W hotend for fast heat-up

An alternative for high-speed profiles: a ceramic 48 W hotend heats faster and holds temperature more steadily at high flow. It's a sensible swap if the stock heater can't keep up with the feed rate on a 0.2 mm layer.

• Fast warm-up — less waiting to start
• Steady temperature at high flow
• Works with the S1 quick-swap system

Difficulty: medium. Compatibility: Kobra S1. Like any hotend swap — PID calibration afterwards.

6. Auxiliary cooling fan: +15° on overhangs

Stock cooling isn't always enough on tricky overhangs. Anycubic's official auxiliary cooling fan mounts into pre-drilled carriage holes (no drilling) and plugs into the AUX_FAN header. Per the maker's own test, it enables stable overhangs up to 70° versus 55° without it — about a +15° gain.

• Stable overhangs up to 70° instead of 55°
• Uses factory holes — no drilling required
• Official part — no firmware compatibility issues

Difficulty: medium (remove the rear cover, plug in the connector). Sold in the official Anycubic store and by resellers.

7. Ball-bearing 5020 part-cooling fan

The stock sleeve-bearing part fan gets noisy and weak over time. Swapping to a 5020 dual ball-bearing fan makes the machine quieter and lasts longer — bearings outlive sleeves, especially in a warm enclosed chamber.

• Quieter and longer-lived than the sleeve fan
• Even airflow — cleaner overhangs and bridges
• Direct fit for the S1 mount

Difficulty: medium. Compatibility: Kobra S1. Watch connector polarity when wiring.

8. Quiet fan mods: bigger fans, lower voltage

To fight noise, the community prints adapters for larger fans (on the mainboard and PSU) and undervolts them. A big fan at low RPM moves the same air far more quietly. Find models on Printables/MakerWorld under 'Kobra S1 silent fan.'

• Noticeably lower noise at idle and while printing
• Less high-pitched whine from tiny fans
• Printed adapter shrouds — free

Difficulty: advanced — rewiring/soldering the power feed. Be careful with voltage so weak cooling doesn't cook the board.

9. HULA anti-vibration feet

Printed HULA feet (and damper adapters) absorb chassis vibration, cut noise and indirectly clean up prints at high acceleration. It's one of the simplest mods — printable in an evening. If you see ringing and ghosting on walls, start with vibration isolation.

• Quieter chassis — less vibration into the shelf/bench
• Sometimes visibly cleaner walls at speed
• Prints in TPU/PLA, installs in minutes

Difficulty: easy. Model: HULA v1.0 for Kobra S1/S1C on Printables. Free.

10. OrcaSlicer profiles over the stock slicer

Reviews agree: 'good printer, bad slicer.' The most effective free mod is switching to OrcaSlicer with community profiles (e.g. the MPC561 set on GitHub). The stock profile uses 1.5 mm retraction — hence holes at seams; volumetric flow is capped at 12–15 mm³/s, while PETG really does ~23 and ABS ~28 mm³/s. Community profiles fix retraction, raise flow and improve the first layer with a nozzle clean. For the first layer, our adhesion guide helps too.

• Fewer seam holes — proper retraction instead of 1.5 mm
• Higher real speed: 23–28 vs 12–15 mm³/s flow
• Steadier first layer and Z-offset via improved start code

Difficulty: medium (import profiles, check 5×5/7×7 bed mesh). Free. The profile repo is active and updated.

11. Rinkhals: Klipper, Mainsail and root access

The deepest mod is the open Rinkhals firmware. It layers on top of the stock system and adds full Klipper, Moonraker, Mainsail, Fluidd, USB camera support and root SSH access, while keeping the native Anycubic screen and calibration. Important: use the current community fork rinkhals-community/Rinkhals — the old jbatonnet repo is deprecated (since July 2026). The firmware is tied to your stock firmware version, so check compatibility first.

• Full Klipper with Mainsail/Fluidd and Moonraker
• Root over SSH, USB camera, apps (OctoEverywhere, Tailscale)
• Keeps the stock Anycubic screen, calibration and tools

Difficulty: expert. Free and open source. The repo is active (recent releases), but it assumes Klipper knowledge.

12. Fine-tuning Input Shaper via Klipper

Once Rinkhals is on the S1, manual Input Shaper and acceleration tuning open up — things the stock software locks. A well-picked shaper removes ghosting and ringing on walls and lets you raise real speed without losing quality.

• Manual shaper choice tuned to your machine's resonances
• Less ghosting on vertical walls
• Higher safe accelerations — faster without defects

Difficulty: advanced. Requires Rinkhals/Klipper and a resonance measurement. Free.

13. Reusable spools to stop ACE Pro tangling

ACE Pro is picky about spool size: third-party filament often tangles into a bird's nest. A simple fix is re-spooling onto correctly sized Anycubic reusable spools. For multicolor and ACE Pro care in general, see the ACE Pro guide.

• Correct diameter — fewer tangles and feed drops
• Even winding eases load on the feed gear
• Reusable — cheaper than third-party spools

Difficulty: easy. Compatibility: Kobra line. A good first step if ACE Pro fights your third-party filament.

14. Cleaning the ACE Pro 4-in-1 PTFE splitter

The most common ACE Pro bug: filament loads to the head, but the cutter trims it just before the start — and the print fails with a clog error. The cause is filament fragments stuck in the 4-in-1 PTFE splitter at the back; the stock splitter has no internal guides. Regular cleaning (or, in bad cases, swapping for a splitter with PTFE guides) fixes it. Other S1 bugs are covered in our known issues article.

• Clears the clog/filament-cut error at print start
• Steadier color changes — fewer ruined multicolor prints
• Cleaning every few spools extends feed-path life

Difficulty: medium. Tool — S2.5 hex key. If the feed port is badly worn, replace the PTFE tubes/splitter.

15. Anti-tangle guide and return detection

The S1 has a signature bug: ACE Pro retracts spools on every start, and after about five parts the filament unwinds out of the holes (the Kobra 3 Combo doesn't do this). A printed anti-tangle guide with PC4-M6 fittings keeps the path straight and holds filament in the PTFE on a failed retract. Paired with the official return detection module, color changes get noticeably more reliable.

• Filament stops unwinding out of ACE Pro after a batch
• Straight entry — fewer tangles on retract
• Return detection catches feed faults before defects

Difficulty: medium. The guide prints for free; the return detection module is an official S1 Combo part.

16. Printed ACE Pro upgrades

A whole ecosystem of printed add-ons surrounds ACE Pro: a riser/tray (so the unit sits above the screen), a buffer, lid stops, and a PTFE guide with a desiccant bay. They make daily use nicer and help keep filament dry. On drying filament, see our dedicated filament drying guide.

• Riser lifts ACE Pro above the screen — easier access
• PTFE guide with desiccant keeps filament dry at the entry
• Lid stops and buffer — small things that annoy less

Difficulty: easy. Models are in the Kobra S1 collections on MakerWorld and Printables. Free.

17. Door seal and chamber heating for ABS/ASA

The Kobra S1 is enclosed, but passive chamber temperature isn't always enough for ABS/ASA and nylon — hence warping and weak layer bonding. A printed door seal holds heat, and an active chamber heating mod (Printables, bolt-on) raises the temperature on purpose. On fighting warping, see our warping guide.

• Stable chamber temp — less ABS/ASA warping
• Better layer bonding on engineering materials
• The door seal prints for free

Difficulty: medium. The seal is a print; active heating needs careful mounting and awareness of the electronics-overheating risk.

18. Air filtration: refillable filter and AirPure 2.0

When printing ABS/ASA, the enclosure traps odor and volatiles — which need filtering. A printed refillable carbon chamber filter and the external AirPure 2.0 purifier cut odor and capture particles. Why this matters for health is in our fumes and ventilation guide.

• Less ABS/ASA odor in the room
• Refillable carbon — cheaper to swap than a whole unit
• AirPure 2.0 works with Photon and Kobra S1

Difficulty: easy. Filtration isn't a substitute for extraction: vent outside if you print ABS regularly.

19. Steel runout flag and small wins

The stock plastic filament-runout flap wears down and starts to false-trigger. A steel flag restores reliable detection. Also here: nice small wins — a nozzle cleaning brush, a door handle with a hygrometer, and a clip protector for the PTFE tube at the head (easy to damage during maintenance).

• The steel flag doesn't wear like the plastic one
• The brush auto-cleans the nozzle before printing
• A hygrometer in the door handle shows chamber humidity

Difficulty: easy/medium. Cheap parts, but they noticeably cut the number of annoying faults.

20. S1 Carbon: carbon rods and a custom duct

An expert mod from the Russian community: swapping the stock steel rods for carbon ones drops the moving mass from about 500 g to 100 g — a 5× cut. Plus a custom part-cooling duct (the stock one, the author says, 'blows everywhere but where it should'). The resonance test result: the second X-axis peak tamed, a gentler shaper, and room to raise print acceleration.

• Kinematics mass ~500 → ~100 g — easier to accelerate and stop
• Second X resonance tamed — cleaner at speed
• Custom duct aims airflow right at the print zone

Difficulty: expert — disassembling the kinematics and printing/sourcing parts. For those squeezing maximum speed from the S1.

Where to start: priority order

Don't grab everything at once. A sensible route from simple to complex:

1. Switch to OrcaSlicer with community profiles — free and changes quality immediately
2. Match the build surface to your material (CryoGrip/textured/Cool Plate)
3. Sort out ACE Pro: clean the splitter + reusable spools + anti-tangle guide
4. Add the auxiliary cooling fan — instantly better overhangs
5. Hardened nozzle or all-metal hotend — if you print abrasives/engineering materials
6. Seal and heat the chamber — for reliable ABS/ASA
7. Rinkhals and fine Input Shaper — once you hit the stock machine's ceiling

And don't skip maintenance: a clean nozzle, lubed rails and tensioned belts save more grief than any upgrade. A basic checklist is in our 3D printer maintenance guide.

Sources

• Anycubic Wiki — Kobra S1 auxiliary cooling fan install
• Anycubic Wiki — ACE Pro clogging
• Tom's Hardware — Kobra S1 review (good printer, bad slicer)
• Rinkhals (community fork) — custom Klipper firmware for Kobra S1
• MPC561 — OrcaSlicer profiles for Kobra S1
• r/AnycubicKobraS1 — optimized 0.4 mm profiles
• r/AnycubicKobraS1 — solving the clog/filament-cut error
• r/AnycubicKobraS1 — ACE Pro anti-tangle guide
• Printables — HULA anti-vibration feet
• Printables — active chamber heating for Kobra S1
• MakerWorld — Kobra S1 upgrades collection
• 3dtoday — turning the Kobra S1 into an S1 Carbon

FAQ