Bed levelling a 3D printer: manual, automatic, and first-layer fixes

Bed levelling is the single biggest factor in whether your first layer goes down cleanly. Too far from the bed and the plastic just falls through the air and does not stick. Too close and the nozzle grinds into the surface and clogs. Get it right and every print after that is easier.

Why the first layer matters so much

A bad first layer does not just make the bottom of your print look rough. It gives the rest of the print a wobbly foundation. Corners lift. Layers separate. Tall prints shift mid-way through. Most failed prints that people blame on slicer settings are actually a levelling problem.

Manual vs automatic: which does your printer use?

Older and budget printers — Ender 3, most basic Creality machines — use manual levelling. You adjust four or five screws under the bed by hand until the nozzle sits at the right height across the whole surface.

Newer machines use automatic bed levelling (ABL). The Bambu Lab X1, P1, and A1 series, the Creality K2, and the Prusa MK4 all have a probe that maps dozens of points across the bed before each print, then compensates for any tilt or warping in software.

Both work well. ABL is faster to set up and more consistent, but manual levelling on a well-maintained printer can be just as reliable once you have the feel for it.

How to level manually: the paper method

This works on any printer with adjustment screws under the bed.

1. Heat the nozzle and bed to your normal printing temperatures. Metal expands when hot, so levelling cold gives you the wrong gap. 2. Home all axes (G28 in the console, or from the printer menu). 3. Disable the steppers so you can move the printhead by hand — usually a menu option, or send M84. 4. Place a sheet of ordinary printer paper under the nozzle at the front-left corner. 5. Adjust the corner screw until you feel light friction when you slide the paper. The nozzle should drag slightly but not tear it. 6. Repeat at the other three corners, then check the centre. 7. Go around a second time. Adjusting one corner pulls the others slightly, so a second pass catches any drift. 8. Print a first-layer test — a flat square or a line grid. Tweak the corners in small increments until the lines are squished flat with no gaps between them.

The paper gives you a starting point. The print test is what tells you if it is actually correct.

Z offset: the step most people miss

Even after levelling, you usually need to fine-tune the Z offset — the precise distance between the nozzle and the bed at the home position. This is separate from the levelling screws and is one of the most common causes of a poor first layer.

If your first layer looks like a string of rounded blobs sitting on the surface rather than being squished into it, your Z offset is too high. If the nozzle is grinding into the bed or your extruder is clicking, it is too low.

Most printers let you adjust Z offset live while the first layer is printing. On Marlin-based machines look for Babystep Z in the tune menu. On Klipper printers, use SET_GCODE_OFFSET or the Z Offset control in Mainsail or Fluidd.

Make small changes — 0.05 mm at a time — and watch how the plastic lays down before adjusting again.

How automatic bed levelling actually works

ABL probes the bed surface before each print, building a height mesh. The firmware then tilts the print path in software to match the actual bed surface, compensating for a warped or slightly tilted sheet.

This means even if your bed has a bow in the middle — very common on larger printers — the printer adjusts on the fly. What ABL cannot fix is a Z offset set incorrectly, or a bed that is wildly out of level beyond the probe's compensation range.

After ABL runs, you still need a correct Z offset. ABL maps the shape of the surface. Z offset tells the printer where the surface actually is. You need both.

Diagnosing common first-layer problems

Corners lifting: Usually the bed is too cold for the material you are running, or the surface is dirty. Clean the sheet with IPA, and try raising the bed temperature by 5 degrees.

Lines not bonding to each other: Z offset is too high. Lower it in 0.05 mm steps until the lines merge.

Nozzle dragging through lines it already printed: Z offset is too low. Raise it slightly.

Good adhesion in the centre, lifting at the edges: The bed is warped. ABL will help significantly here. You can also try a brim in your slicer to increase edge contact.

Good adhesion on the left, gaps on the right: The bed is tilted. Go back to the levelling screws and raise the low side.

How often should you re-level?

On a stable printer sitting on a solid bench, you might only need to check levelling every few weeks or after a nozzle change. If you move the printer, swap build surfaces, or have a print failure where the nozzle crashed into the bed, check it before the next job.

Printers with magnetic PEI sheets are generally more consistent than glass beds because the sheet snaps back to the same position every time you remove and replace it. If you are constantly fighting your levelling, check the sheet itself for warping — a dished or humped surface defeats even the best manual technique.

Which approach is actually best?

For most people: ABL with a correctly set Z offset, on a printer running Klipper or a recent version of Marlin. The Bambu Lab machines take this furthest — they run a full bed mesh plus vibration compensation automatically, with almost no user input needed. The Creality K2 series uses a similar prtouch-based system.

If you have a manual printer, the paper method works. The key is running a print test after and making the final adjustment based on how the plastic actually looks — not just how the paper feels under the nozzle.

When to get it printed instead

If you are spending more time levelling than printing, or if a warped or damaged bed is giving you grief that no amount of adjustment will cure, it may be simpler to send the file to us. We run calibrated machines that are checked before every job, so the first layer is not your problem. If you just need a part in your hands without the troubleshooting session, take a look at our printing service — you send the file, we handle everything else.