The short answer
Calibration means measuring your printer so it puts down the right amount of plastic in the right place. For a beginner, three checks matter most: bed leveling, nozzle height (Z offset), and flow. Many newer printers run most of this for you.
In this post
What does calibration look like on a new printer?
In Part 2 of our Bambu Lab H2C setup, Basil walks Gina through installing the hot ends, watching the printer read each one, and sending her first print.
Jump to the hot-end check at 7:45 (opens in a new tab) or the first layers at 22:16 (opens in a new tab). Part 1, with the first full calibration, is in our H2C setup post (opens in a new tab).
1. Bed leveling
The nozzle has to sit the same tiny distance above the bed everywhere it prints. If one corner is higher, prints stick on one side and peel on the other.
- Automatic leveling: the printer touches or scans points across the bed and builds a map of the surface. Many printers do this before every print. Ours spends about 5 to 7 minutes leveling the bed and checking flow before each one starts.
- Manual leveling: you turn knobs under the bed while sliding a sheet of plain paper under the nozzle at each corner. You want a light drag on the paper, the same at every corner.
2. Nozzle height (Z offset)
Even on a level bed, the nozzle can sit a bit too high or too low. That gap is the Z offset, and it decides whether the first layer sticks.
- Too high: lines look round, like cooked spaghetti, and don't stick.
- Too low: lines look thin and see-through, or the nozzle scrapes.
- About right: lines are slightly flattened and touch each other.
Adjust in very small steps and print a single-layer test square between changes. Our post on why the first layer won't stick (opens in a new tab) covers what to look for.
Still can't get the first layer to stick? Book a free 10-minute call (opens in a new tab) with a Z-Access founder and we'll talk through what you're seeing.
3. Flow
Flow controls how much plastic comes out. Too little leaves gaps between lines. Too much makes the top surface rough and blobby, and parts come out a little too big. Most slicers include a flow test: print it, pick the cleanest square, and save that value for that filament.
4. Vibration compensation
Newer fast printers shake themselves on purpose during setup to measure how the frame vibrates, then adjust their motion to cancel it. That's the loud, shaky part of a first calibration. On our H2C, the first full calibration showed about 30 minutes, and the shaking is normal.
5. Pressure advance
When the nozzle slows for a corner, pressure inside can push out a little extra plastic, so corners bulge. Pressure advance (some printers call it flow dynamics) adjusts for that. Many newer printers calibrate it on their own for each filament. On others, your slicer has a test print.
6. Temperature
Each filament has a temperature range printed on the spool. A temperature tower prints one section at each temperature so you can pick the one that looks best. It's also a fix for 3D printer stringing (opens in a new tab).
When should you calibrate a 3D printer?
- When the printer is new, run the full built-in calibration before your first print.
- After you move the printer, even across the room.
- When you switch to a new type or brand of filament, check flow and temperature.
- After you change a nozzle or hot end.
- When prints that used to come out fine suddenly don't.
A simple routine
- Step 1:
First day
Full built-in calibration, then a small test print you can watch start to finish.
- Step 2:
Each new filament
Flow test, plus a temperature tower if it strings or looks rough.
- Step 3:
Every print
Watch the first two or three layers. Most failed prints fail there.
Follow along
We film our own setups, mistakes included, on YouTube (opens in a new tab), Facebook (opens in a new tab), and TikTok (opens in a new tab).
Questions new owners ask
How often should I calibrate my 3D printer?
Run the full calibration when the printer is new or after you move it, check flow and temperature for each new filament, and recheck any time prints change for no clear reason.
Do I need to calibrate a brand-new printer?
Yes. Even printers that level themselves run a first calibration when you set them up. Let it finish before your first print.
What is the paper test?
A way to set nozzle height by hand. With the printer homed, slide plain paper under the nozzle and adjust until you feel a light drag at each corner.
What is Z offset?
The fine adjustment for how high the nozzle sits above the bed for the first layer. It's the main setting that decides whether prints stick.
Why does my printer shake during calibration?
Newer printers vibrate on purpose to measure their frame and smooth out their motion. It's loud and it's normal.
