Snapmaker U1 Problems and How to Fix Them

The Snapmaker U1 is a toolchanger with the SnapSwap system, four extruders, and printing speeds up to 350 mm/s. The printer launched in late 2024, and the community has since accumulated plenty of information about typical issues. This guide covers real bugs, error codes, and specific fixes — from slicer settings to hardware mods.

SnapSwap System Issues

Pogopin Contact Error (0002-0523-xxxx-0045)

The screen displays Toolhead swapping abnormal, Toolhead X Pogopin contact anomaly. The cause is dirty or poorly contacting gold-plated Pogopin connectors on the toolhead and swapper.

Fix: Wipe the Pogopin and Solidpin with isopropyl alcohol and a lint-free cloth. The SnapSwap system is rated for 1,000,000 toolhead swaps, but every 100,000 swaps a cleaning reminder appears. If the problem persists, enter GET_EXTRUDER_SWITCH_RECORDER in the Fluidd console — the retry_count parameter shows the number of retry attempts. If retries are frequent, you may need to replace the PCBA on the toolhead (takes less than 5 minutes).

Toolhead Grabbing Failure (0002-0523-xxxx-0021/0023)

The toolhead fails to be picked up from or parked back to the dock. Error codes: 0002-0523-0000-0021, 0002-0523-0000-0022, 0002-0523-0000-0023 (for toolhead 1), with similar codes for toolheads 2–4.

Fix: Check three things. First, make sure the toolhead latch is positioned correctly — the red indicator should be visible before installation and hidden after. Second, check belt tension. Third, if everything looks fine, recalibrate the pick-and-park coordinates through the screen (firmware 0.9.4+ required).

Internal Panel Blocking Parking on First Boot

During first calibration, the toolhead may fail to park. A common cause is applying excessive force when installing the filament holder, which causes the left or right internal panel to pop out of its slot and physically obstruct the carriage movement.

Fix: Inspect the internal panels and push them back into place if needed. Then re-run calibration.

Print Quality Issues

VFA Artifacts (Vertical Fine Artifacts)

Periodic vertical lines on walls are a common issue for many high-speed printers, and the U1 is no exception. VFAs occur due to stepper motor resonance frequencies at certain speeds.

Fix (free, slicer only): First, run the built-in VFA test from the calibration menu in Snapmaker Orca (range 100–300 mm/s) to identify problematic speeds. Then set the following parameters:

• Outer wall speed: 210 mm/s (or your determined minimum VFA-free speed)
• Inner wall speed: 210 mm/s
• Outer/Inner wall line width: 0.4 mm
• Walls printing order: Inner/Outer/Inner

Prime Tower Falling

During multi-material printing, the wipe tower (prime tower) can lean and collapse, especially on tall models. This causes print failure and potential model damage from nozzle collisions.

Fix: In Snapmaker Orca, adjust the prime tower settings:

• Wall type: Rib (improves resistance to tipping)
• Minimal purge on wipe tower: 10 mm³ instead of the default 60 mm³ (in filament settings, Multimaterial section)
• Prime Volume: 15–18 mm³
• Increase Rib Length for a wider tower base footprint

First Layer Issues

Poor first layer adhesion is a common issue, especially after extended use of the PEI sheet.

Fix:

• Clean the PEI sheet with isopropyl alcohol. If the surface is worn, flip it to the fresh side
• Calibrate Z-offset: adjust in steps no larger than 0.05 mm. During printing, use the hidden menu (swipe left on the touchscreen) to fine-tune
• Run automatic bed calibration: Settings > Device Calibration > Heated Bed Leveling
• Reduce first layer speed to 20 mm/s or below
• Clean the nozzle at 200°C (PLA) or 230°C (ABS) using the included brush

Hardware Issues

TMC Driver Overheating

The stock heatsink sits on top of the TMC driver chips, but these chips dissipate heat through their bottom side. As a result, the plastic mainboard absorbs most of the heat. Driver temperatures can reach 70°C just during homing and 80–82°C while printing.

Fix: Install a modified heatsink that contacts the bottom side of the chips. A 3D-printable mount is available on Printables. After the mod, temperatures drop to 56–59°C. This is an unofficial modification, but it significantly improves motor driver stability.

Z-Axis Knocking Noise

A metallic knocking sound, similar to something hitting the plastic base. It occurs during rapid Z-motor direction changes — the motor generates an instantaneous reverse force that transmits through the mechanical structure to the plastic base.

Fix: In Snapmaker Orca, change the Z-hop type for extruders 1–4 from Auto to Normal. This eliminates the spiral lift motion that causes the knocking. Also lubricate the Z-axis lead screw quarterly — without lubrication the noise intensifies.

Bed Vibration

Some users report noticeable bed vibration when printing at high speeds. This is caused by structural resonance at certain motion frequencies.

Fix: Place the printer on vibration-dampening feet or a concrete slab. Make sure the printer sits on a flat, rigid surface. Re-run Input Shaper calibration — it can reduce vibrations at problematic frequencies.

Software Issues

Wi-Fi: 2.4 GHz Only

The U1 supports 2.4 GHz Wi-Fi only. The 5 GHz band is not supported and will not be added (hardware limitation of the Wi-Fi module). Some routers with advanced features like band steering or mesh networking may cause connection issues.

Fix: Create a dedicated 2.4 GHz network with a fixed channel and band steering disabled. If the printer cannot obtain an IP address, restart both the router and the printer. Firmware versions before V0.9.0 have cloud connection issues — update accordingly.

Screen Not Working After V1.1.0 Update

After updating firmware to V1.1.0 without manually restarting the machine, the touchscreen goes black and becomes unresponsive.

Fix: Update to V1.1.1, which resolves this bug. Download the firmware to a USB drive and update via Settings > About > Firmware Version > Local Update. If the screen is unresponsive, perform a power cycle before attempting the update.

Snapmaker Orca Lags Behind OrcaSlicer

Snapmaker Orca is a fork of OrcaSlicer with SnapSwap integration. However, it lags behind the upstream version, and known bugs are fixed with a delay:

• Versions before V2.1.2: decimal points were replaced with commas under German or French locale, breaking G-code
• Versions before V2.1.5: false warning G-code path goes beyond plate boundaries on models smaller than full volume
• Versions before V2.1.1: connection bug with U1 (while Fluidd and Snapmaker App worked normally)

Fix: Always update to the latest version of Snapmaker Orca. If you critically need a feature from a newer OrcaSlicer release, you can use standard OrcaSlicer for slicing but send jobs to the U1 via the Snapmaker App.

Error Codes Reference

U1 error codes consist of four groups of four digits. Below are the most common errors and their meanings:

For the complete error code table, visit the Snapmaker Wiki.

Conclusion

The Snapmaker U1 is an ambitious toolchanger, and most of its issues are resolved through firmware updates, proper slicer settings, or routine maintenance. Snapmaker actively updates its Wiki and releases fixes, while the community shares solutions on the forum. The key takeaway: keep firmware and Snapmaker Orca up to date, regularly clean SnapSwap contacts, and don't hesitate to experiment with slicer settings.