3D print first layer not sticking? Check gaps and ridges
On Prusa's i3 smooth-sheet calibration, gaps suggest the nozzle may be too far away, while ridges or curling suggest it may be too close. Evenly joined lines that later lift point toward surface, profile, leveling, or extrusion checks. These are clues from one model's test, not a universal diagnosis or a reason to copy its Z offset. Use the calibration procedure and plate profile for your exact printer.
Choose the first check from the pattern
Use a completed first-layer test or the first layer of a failed print. Describe whether the symptom appears across the whole pattern or only in one area, and whether you saw it while lines were being laid or only after the part began to lift. The checks below are ordered by what the appearance can support. Prusa's nozzle-distance descriptions specifically refer to its i3 calibration and sheet types; for another printer, use its own calibration instructions rather than importing those adjustments.
Scroll the table sideways to read every column.
| Visible result | Next documented check | How the result changes the decision |
|---|---|---|
| Lines are round or separated over most of the sample. | First confirm the selected plate or sheet profile matches the sheet installed. On a Prusa i3 smooth-sheet calibration, gaps are a sign to check nozzle distance using that model's first-layer procedure. | If the calibration pattern becomes even, with lines joined and without ridges, stop changing nozzle distance and test adhesion separately. If gaps remain, follow that printer's calibration instructions or diagnostics; a photo cannot give an offset value. |
| Lines look very flat, with ridges between them or edges curling up. | On the Prusa i3 smooth-sheet calibration, ridges and curling indicate the nozzle may be too close. Use the model-specific calibration instructions to correct it; do not reuse someone else's numeric offset. | If ridges clear and the pattern becomes even, the spacing clue has changed. If the nozzle contacts the sheet, the printer reports a fault, or the result remains distorted, stop calibration and use the manufacturer's troubleshooting path. |
| One corner or region differs while other areas look even. | Check that the sheet is seated as the printer manual specifies, then consult that model's bed-leveling or mesh-calibration procedure. | If the region-to-region difference changes after the prescribed check, investigate leveling or the affected area. If the full pattern is now even but the print still lifts, move to the adhesion row. |
| Lines join evenly, but the print later peels or will not stay attached. | Confirm the surface is clean using its maker's instructions, the installed sheet matches the selected profile, and the material and slicer profile are intended for that setup. | If those match and the same line pattern still lifts, investigate model-specific bed leveling, settings, or extrusion diagnostics. Your observation of when lifting began distinguishes these cases; a finished-sample photo alone cannot establish the timing or identify the responsible setting or component. |
Compare before and after, not two guesses
Keep the test pattern, spool, plate, slicer profile, and camera view the same. Record the single documented check or adjustment between samples. A defect that follows one bed region is different evidence from ridges across the whole pattern. A smooth pattern followed by edge lift shifts attention away from nozzle distance and toward the surface, profile, or the printer's adhesion and extrusion checks. If you changed several things at once, the next print cannot show which one mattered; return to a documented baseline when the printer maker's instructions allow it.
Hypothetical A/B example: A Prusa i3 smooth-sheet calibration shows gaps across the test square. After following that printer's calibration procedure, B has evenly joined lines without ridges. Decision: stop adjusting nozzle distance. If a separate print still lifts at one edge, check sheet cleanliness and the selected sheet/material profile; the improved square does not establish those conditions. This illustrates the decision path and is not a report of a physical test.
Make the image optional evidence
For a one-off question, manually attach a photo of the completed sample and type the printer model, plate, material, and check you already tried. If you are comparing repeated tests and an MCP camera session is already available, request one fresh still after each sample has cooled. LetItSee supplies requested stills; it does not watch the first layer, measure a gap, or alter printer settings.
Prompt to adapt
Use the manually attached photo, or request one fresh still of the completed, cooled sample if an MCP camera session is available. Printer/model and firmware: [ ]. Installed plate and selected plate profile: [ ]. Filament/material and slicer profile: [ ]. Test pattern and layer height: [ ]. Symptom and location: [separated lines / ridges / joined lines that later lifted; whole bed or region]. Baseline result: [ ]. One model-documented check since baseline: [ ]. First describe the visible pattern. Which row in the symptom table fits best, what one documented check follows, and what result would make us switch to a different explanation? Do not suggest a universal Z offset.
Source documentation
Set up without starting a capture
Set up your MCP client with the full tool reference. The separate capture page can replace the active capture page for your account. It does not take a photo by itself.