The Ins and Outs of Auto Leveling 3D Printers

Auto leveling, also known as auto bed leveling, is one of the most useful features for 3D printers today. By automatically measuring the print bed and adjusting for any unevenness, auto leveling ensures your first layer adheres perfectly every time. This results in more successful prints and less wasted filament and time.

In this comprehensive guide, we’ll cover everything you need to know about auto leveling 3D printers including how auto leveling works, the different types of sensors used, the pros and cons, how to use and set up auto leveling, and our top recommendations for auto leveling 3D printers.

How Does Auto Leveling 3D Printers Work?

Auto bed leveling uses sensors to scan multiple points across the print surface before each print. It then adjusts the nozzle height at each point to compensate for any unevenness. This results in a perfectly even first layer height across the entire print bed.

Here is the basic process an auto leveling 3D printer goes through before printing:

1. The print head moves to the first probing point and lowers until the sensor triggers. This stores the height of that point.
2. Steps 1 is repeated at multiple points across the bed to map it.
3. The printer firmware uses the map to create a mesh that compensates for the unevenness.
4. Right before printing, the nozzle height is automatically adjusted at each point based on the mesh so the first layer height is even.

Some key terms:

• Probing points: The locations on the bed the sensor checks the height at. More points means a higher resolution mesh.
• Mesh: The compensation map created from the probing points.
• Z-offset: Fine tunes the distance between the nozzle and bed across the whole mesh.

Types of Auto Leveling Sensors

There are several different types of sensors used for auto leveling on 3D printers. Each has its own pros and cons.

• Inductive Proximity Sensor: Uses electromagnetic fields to detect metal. Simple, low cost option good for PLA.
• Capacitive Sensor: Detects any material type by electrical charge. Higher resolution than inductive but more expensive.
• BLTouch: Popular branded capacitive sensor with high precision and reliability.
• Servo Actuated Z Probe: Uses a servo to lower and raise a switch probe. Very accurate but slower than other methods.
• Strain Gauge Sensor: Advanced method that uses weight to map bed. Found on high end printers.
• Optical Sensor: Uses light beams to detect the surface. Versatile option good for exotic bed materials like glass.

Each sensor type has a different triggering distance, precision, speed, and compatibility with different bed surfaces like glass, PEI, or buildtak. Choosing the right one depends on your specific printer and needs.

Benefits of Auto Bed Leveling

Here are some of the major benefits auto leveling provides for 3D printing:

• Perfect First Layer Adhesion: By compensating for an uneven bed, auto leveling ensures your first layer squishes down evenly for maximum bed adhesion across the entire print surface. This prevents warping and detachment.
• Foolproof Bed Leveling: Manual bed leveling is tedious and you have to redo it regularly as the bed gets knocked out of alignment. Auto leveling is completely hands-off and hassle-free.
• No More Failed Prints: Uneven bed height is one of the most common causes of failed 3D prints. Auto leveling solves this issue resulting in a much higher print success rate.
• Flexible Bed Materials: Auto leveling works with exotic bed surfaces like glass and mirror that can be tricky to manually level. The automatic adjustments compensate for their inconsistencies.
• Consistent First Layers: Even if you manually achieve a perfect level, it can quickly go out of alignment. Auto leveling ensures every print starts with an ideal first layer.
• One Less Thing To Worry About: Getting the perfect manual level takes skill and experience. Auto leveling makes printing easy for beginners. Just load, slice, and print without worries.

Potential Drawbacks of Auto Leveling 3D Printers

Of course no technology is perfect. Here are a few potential limitations to consider with auto leveling 3D printers:

• Increased Cost: The sensors and other required hardware additions increase the printer’s bill of materials, so auto-leveling capable machines cost more.
• Leveling Slows Down Printing: The probing process takes a couple minutes before each print reducing throughput for high volume printing.
• Reduced Print Volume: Space is required to accommodate the sensor and its mounting bracket which reduces max print dimensions.
• Potential Mechanical Issues: More moving parts can lead to a higher chance of something failing. The probe itself is delicate and can break with repeated hits.
• May Still Require Occasional Calibration: While auto leveling is largely hands-off, mechanical changes like nozzle swaps may require re-calibrating the sensor’s Z-offset.
• Limited Compensation Range: Auto leveling works best for minor inconsistencies under 0.1mm. Severely unleveled or warped beds may exceed the compensation range.

For most users and applications, the benefits far outweigh the limitations. But it helps to be aware of the potential downsides before purchasing.

How To Use and Set Up Auto Bed Leveling

While auto leveling 3D printers largely work right out of the box, there are a few steps required to enable the feature and optimize it. Here is a typical workflow:

1. Install Sensor Hardware: The probe and mount first need to be physically installed on the print head carriage according to the directions.
2. Update Firmware: Most printers require flashing firmware that contains the auto leveling algorithms and mesh generation code.
3. Run Initial Auto Calibration: Once enabled in firmware, initiate a first auto calibration to test functionality and generate the mesh.
4. Set Z-Offset Height: Dial in the optimal nozzle distance from the bed across the entire mesh for good first layer squish.
5. Check Mesh Visualizer: Use the leveling mesh graphic in your slicer to spot any abnormalities in the bed topography.
6. Set Probing Points: Increase or decrease the number of probe points for faster or higher resolution mesh mapping as needed.
7. Add Bed Leveling Gcode: Make sure your slicer is configured to insert the G29 auto leveling command in the starting gcode.
8. Perform Regular Maintenance: Keep the probe clean and undamaged, check for bed debris, and redo calibration if major mechanical changes are made.

Follow these steps and your auto leveling setup will keep your printer running reliably with perfect first layers.

Top Auto Leveling 3D Printers

Now that you understand the technology, here are our picks for the top 3D printers with auto bed leveling available today:

Prusa i3 MK3S – Under $1,000

Prusa is the gold standard for auto leveling with their mesh bed leveling system and P.I.N.D.A probe. Very accurate, reliable, and hassle-free printing.

Creality Ender 3 Pro – Under $300

An affordable way to get auto leveling thanks to broad BLTouch compatibility. Large community provides setup support.

Ultimaker S3 – $4,995

Advanced leveling sensor and algorithms combined with excellent hardware quality. Made for professional use.

FlashForge Creator Max – $1,199

Reliable dual extruder printer with ample build volume and built-in inductive sensor for simple auto leveling.

Artillery Sidewinder X2 – $669

Great mix of large print size, fast speed, and easy auto leveling integration with BLTouch or clones.

Anycubic Vyper – $379

Capable auto leveling right out of the box thanks to integrated touch screen interface and step-by-step calibration.

Auto leveling has become an essential feature for hassle-free 3D printing. While the hardware costs more, it pays for itself in time and filament savings from smooth first layers and higher print success rates. For prosumers and businesses producing high value prints, the benefits easily justify the investment. Even hobbyists find auto leveling alleviates a major pain point.

If consistently flawless first layer adhesion sounds good, look for one of the quality auto leveling printers in this guide. In no time you’ll be cranking out prints with ease and wondering how you ever manually leveled your bed.