Best Voron Z Probe — Klicky vs Euclid vs Tap vs Sensorless vs Inductive

Probe Electronics Comparison

The Z probe is one of the most debated topics in the Voron community. It directly affects your first-layer consistency, bed mesh quality, and overall print reliability. A bad probe means failed prints, damaged PEI sheets, and hours of frustration. A good probe means set-it-and-forget-it bed leveling for months. Last updated: May 2025.

In this guide, we compare five Z probing methods: inductive probes (PL-08N, TL-Q5MC), Klicky (docking mechanical switch), Euclid (magnetic docking probe), Tap (direct nozzle contact), and sensorless homing (stall detection). We cover repeatability in microns, Z offset stability, temperature sensitivity, cost, installation difficulty, toolhead compatibility, and common failure modes.

At a Glance — Probe Comparison Table

Tap — The New Gold Standard

Tap is a Voron community-designed probe that replaces the entire Stealthburner toolhead lower body with a vertically-sliding carriage. The nozzle contacts the bed directly, pushing the entire carriage upward until a mechanical endstop (microswitch or optical sensor) triggers. This means Tap measures the true nozzle-to-bed distance with no offsets, no temperature drift, and no calibration drift over time.

Pros: Unmatched repeatability — ±2 µm is typical, and many users report consistent probes within ±1 µm. No Z offset drift because there is no offset to calibrate — the nozzle is the probe. Not affected by temperature changes (the nozzle doesn't change length meaningfully with heat). Extremely reliable — the single moving part is the sliding carriage on linear rails. Can probe hot or cold beds (inductive probes fail on cold PEI). Print start macros are simpler because you don't need to dock and undock the probe.

Cons: Stealthburner-only — you cannot use Tap with Afterburner, Mini Stealthburner, or other toolheads. The sliding carriage adds approximately 45g to the toolhead mass, which reduces acceleration limits and requires retuning input shaper. The probe action uses the Z motor to push the nozzle into the bed — if your Z endstop or probe trigger fails, you can crash the nozzle into the bed. There is a minimum Z hop requirement (typically 5-10mm) to clear the probe trigger point.

Best for: Voron V2.4 and Trident builds that can handle the extra toolhead mass. Tap is the most accurate and maintenance-free probing method available. If you want the best first layers possible and don't mind tuning input shaper after installation, Tap is the clear winner.

Tap Klipper Config

[probe]
pin: ^!PA7                  ; Check your board pin mapping
x_offset: 0.0               ; Tap has zero X/Y offset from nozzle
y_offset: 0.0
z_offset: 0.0               ; Calibrated via PROBE_CALIBRATE
speed: 5.0                  ; Probing speed in mm/s
lift_speed: 10.0            ; Lift speed after probe
samples: 3
samples_result: median
sample_retract_dist: 3.0
samples_tolerance: 0.005    ; 5µm tolerance between samples
samples_tolerance_retries: 3

[stepper_z]
endstop_pin: probe:z_virtual_endstop
position_endstop: 0.0
    

Klicky — Budget Mechanical Accuracy

Klicky is a dockable mechanical probe that uses a microswitch mounted on a 3D-printed arm. The probe docks on a printed holster mounted to the frame or gantry. When homing or probing, the toolhead moves to the dock, picks up the probe via a magnet on the probe body, performs the probe, and returns the probe to the dock. It was the first community-designed Voron probe and remains extremely popular.

Pros: Extremely low cost — you need a microswitch ($1-2), a magnet ($1-2), printed parts, and a small PCB or wiring. Excellent repeatability for a mechanical switch — ±5 µm is realistic. Compatible with every Voron toolhead (Stealthburner, Afterburner, Mini Stealthburner, V0.2, Switchwire) because the probe mounts to the toolhead body, not inside it. Temperature stable — a microswitch triggers at the same force regardless of chamber temperature. Well-documented with years of community refinements.

Cons: More complex setup than Tap — you need to configure docking macros, probe pick-up routines, and verify that the probe docks reliably every time. The printed arm can wear out over hundreds of dock cycles, requiring re-printing. Mis-docking is the most common failure — if the probe isn't seated fully on the magnet, the probe position is off by 1-2mm. Filament strings can interfere with docking if the nozzle isn't wiped clean before probing. The dock takes up space on the frame and can interfere with cable chains on some builds.

Best for: V0.2 and Switchwire builds where Tap doesn't fit, and Trident builds where you want better accuracy than inductive probes but don't want to add toolhead mass. Also excellent for budget builds — you can build a Klicky for under $10 in parts.

Klicky Klipper Config

[probe]
pin: ^!PC15                 ; Check your board pin mapping
x_offset: 0.0               ; Klicky has zero X/Y offset from nozzle
y_offset: 0.0
z_offset: 0.0               ; Calibrated via PROBE_CALIBRATE
speed: 20.0                 ; Probing speed
lift_speed: 15.0
samples: 3
samples_result: median
sample_retract_dist: 5.0
samples_tolerance: 0.0075   ; 7.5µm tolerance
samples_tolerance_retries: 3

[gcode_macro _PROBE_PICKUP]
gcode:
    ; Move to dock position - adjust coordinates for your build
    G90
    G1 X150 Y250 F12000
    G4 P500
    ; Pick up probe
    PROBE_DOCKED=1

[gcode_macro _PROBE_DOCK]
gcode:
    ; Return probe to dock
    G90
    G1 X150 Y250 F12000
    G4 P500
    PROBE_DOCKED=0
    

Euclid — Magnetic Precision

Euclid is an evolution of the Klicky concept that replaces the microswitch arm with a magnetic docking body. The probe consists of a magnetically-attached body containing a microswitch, which docks onto a magnetic receiver on the toolhead. The key difference from Klicky is that Euclid uses a dedicated PCB and a more refined magnetic latching mechanism for more consistent docking.

Pros: More consistent docking than Klicky — the dual-magnet latch system is less sensitive to positioning errors. The dedicated PCB with status LED helps with debugging. Higher quality microswitch than typical Klicky builds (Omron D2F-5L instead of generic limit switches). Better Z offset stability than inductive probes. The probe body is more rigid than the printed Klicky arm, reducing flex-induced variation. Good community documentation and config templates.

Cons: More expensive than Klicky — the PCB and magnets add up to $12-20 per probe set. Still requires docking macros and careful tuning for reliable pick-up/drop-off. The probe body adds about 8g to the toolhead when docked, which is less than Tap's 45g but still measurable on input shaper tuning. The magnetic connection can lose strength over time if the magnets are exposed to high chamber temperatures (above 70°C). Still uses a microswitch, which has a finite lifespan (~1 million actuations).

Best for: Trident and V0.2 builds where you want better reliability than Klicky without the toolhead mass of Tap. Euclid is also a good upgrade path for builders who started with Klicky and want more consistent docking behavior.

Inductive Probes — PL-08N and TL-Q5MC

Inductive probes were the original Voron probing method. These are simple sensors that detect the presence of metal (your PEI spring steel sheet or aluminum bed). The most common models are the Omron PL-08N (NPN normally open) and the TL-Q5MC (PNP normally closed). They mount on the toolhead via a printed bracket and trigger when the bed surface comes within ~2-4mm of the sensor face.

Pros: Simplicity — no moving parts, no docking, no macros. Wire the sensor to an endstop pin, configure a probe section in Klipper, and probe. Cheap — $3-10 for genuine Omron or $1-2 for generic clones. Works with any toolhead that has a probe mount. No toolhead mass added beyond the sensor itself (~15g). Easy to troubleshoot — if it triggers on a piece of metal, it works.

Cons: Temperature sensitivity is the killer. Inductive probes drift significantly with temperature — as the chamber heats up from 25°C to 60°C, the Z offset can shift by 30-100 µm due to thermal expansion of the probe mount and sensor electronics. This means your first layer calibration at room temperature is wrong when the chamber is hot. The probe must be mounted at a precise distance from the nozzle (typically 2-4mm offset in Z and 20-30mm offset in X/Y), creating a lever arm that amplifies any tilt in the toolhead. The probe only works on metal build plates — a G10/FR4 or glass bed won't trigger it. The 4mm sensing distance means the nozzle can crash into the bed if the probe fails.

Best for: Legacy Voron builds that already have inductive probes installed and working. If you're building a new Voron in 2025, we strongly recommend Tap, Klicky, or Euclid instead. The temperature drift issue alone is enough reason to skip inductive probes.

Inductive Probe Klipper Config (PL-08N)

[probe]
pin: ^!PA15                 ; PL-08N NPN normally open
x_offset: 20.0              ; X offset from nozzle to probe center
y_offset: 0.0               ; Y is typically on center
z_offset: 0.0               ; Calibrated via PROBE_CALIBRATE
speed: 10.0
lift_speed: 15.0
samples: 3
samples_result: median
sample_retract_dist: 5.0
samples_tolerance: 0.010    ; 10µm tolerance (wider due to drift)
samples_tolerance_retries: 3
    

Sensorless Homing — The Zero-Cost Option

Sensorless homing (also called stall detection or TMC homing) uses the TMC2209/TMC2240/TMC5160 stepper driver's StallGuard feature to detect when the axis physically hits an obstruction (the bed or a hard stop). No probe hardware is needed — the driver senses the motor's load and triggers the endstop when the load spikes from the collision. This is commonly used for X and Y homing on Vorons, and some builders use it for Z probing as well.

Pros: Zero hardware cost — it's a feature of the TMC2209/2240/5160 drivers you already have. Zero toolhead mass. No probe mounting, wiring, or maintenance. Works on any build plate material (metal, PEI, G10, glass). No moving parts to wear out. Useful as a backup homing method even if you have a dedicated probe.

Cons: Repeatability is poor compared to dedicated probes — ±15-30 µm is typical, and it varies with temperature, bed surface condition, and axis speed. Requires careful tuning of the stall sensitivity threshold (driver_SGTHRS) — too sensitive triggers early, too insensitive crashes the nozzle into the bed with more force. Not suitable for automatic bed mesh probing — the variance is too high for a useful mesh. The collision force can damage PEI sheets or the nozzle over many cycles. The Z motor must be strong enough to lift the gantry against the bed — a TMC2209 at 1.2A may not reliably detect a stall against a PEI sheet.

Best for: Backup homing method in combination with a primary probe (Tap, Klicky, or Euclid). Many Voron users run sensorless X and Y homing (to eliminate endstop switches) with a Tap or Klicky for Z probing. Using sensorless as the sole Z probing method is not recommended for a daily driver printer.

Sensorless Homing Klipper Config (Z Axis)

[stepper_z]
endstop_pin: tmc2209_stepper_z:virtual_endstop   ; Uses driver stall detection
position_endstop: 0.0
homing_speed: 5.0                                 ; Slow speed for reliable detection
homing_retract_dist: 3.0

[tmc2209 stepper_z]
diag_pin: ^!PD2                                   ; Check your board pin mapping
driver_SGTHRS: 70                                 ; Stall sensitivity - tune this!
    

Troubleshooting Common Probe Problems

Tap — False Triggers

Tap false triggers are usually caused by carriage binding or excessive grease. The sliding carriage needs to move freely — if it binds (too-tight eccentric nuts, misaligned linear rails, or hardened grease), the carriage may not return to its home position after probing. Fix: clean and re-lubricate the linear rails, loosen the eccentric nut slightly, and verify that the carriage drops under its own weight when the toolhead is removed from the printer. False triggers can also occur if the Z homing speed is too high — keep it at 5mm/s or below.

Klicky/Euclid — Mis-Docking

Mis-docking is the most common Klicky failure. The probe magnetically attaches to the toolhead but doesn't seat properly, causing the probe to sit at an angle. Fixes: ensure the toolhead and dock are exactly aligned using a dial gauge or square. Increase the magnet strength (N52 vs N48 magnets). Add a chamfer to the dock's guide surfaces so the probe self-centers. Clean any filament debris from the dock and probe magnet faces. If the problem persists, check your gantry squareness — a racked gantry misaligns the toolhead relative to the fixed dock.

Inductive — Temperature Drift

If your first layer goes from perfect at 25°C to too-high at 60°C chamber temperature, your inductive probe is drifting. The fix is to calibrate the Z offset at temperature: heat the chamber to your typical printing temperature (60°C), let everything soak for 15 minutes, then run PROBE_CALIBRATE. You can also use a Z endstop switch for homing and use the probe only for bed meshing — this separates the homing Z offset (which must be stable) from the mesh (which can tolerate minor drift). Better yet, switch to Tap.

Sensorless — Inconsistent Detection

If sensorless homing triggers at different distances, tune the driver_SGTHRS value. Lower values make detection more sensitive (triggers earlier), higher values make it less sensitive (triggers later with more force). Start at 70 and adjust in increments of 5. The optimal value depends on your Z axis friction, motor current, and gantry weight. Run PROBE_ACCURACY after each adjustment to measure repeatability. If you can't get below ±25µm variation, switch to a dedicated probe for Z.

Recommendations by Voron Model

Voron V2.4: Tap. The V2.4's gantry is heavy enough that the extra 45g of Tap makes a negligible difference to acceleration limits. The unmatched repeatability (±2µm) ensures perfect first layers across the full 350mm print area. Pair with sensorless X and Y homing for a fully endstop-free build.

Voron Trident: Tap or Euclid. Tap if you want the best possible probing accuracy. Euclid if you want to keep toolhead mass low (the Trident's moving bed means the toolhead mass directly affects print quality at high speeds). Both are excellent choices.

Voron V0.2: Klicky or Euclid. Tap doesn't fit the V0.2's Mini Stealthburner toolhead. Klicky is the budget option; Euclid is the refined option. Both give good accuracy without adding significant mass to the tiny V0.2 toolhead.

Voron Switchwire: Klicky. The Switchwire's cantilevered gantry is sensitive to toolhead mass, so Tap is not ideal. Klicky's low cost and good accuracy make it the natural choice. Sensorless Z can work on the Switchwire due to the lightweight bed, but a mechanical probe is more reliable.

Budget recommendation: Klicky. For under $10, you get probing accuracy within ±5µm, temperature stability, and compatibility with every Voron model. It requires more setup than Tap, but the cost savings are significant.