What we tested
| File | Bambu Studio said | Actual problem | Result |
|---|---|---|---|
| Square pyramid 4 mm across, 15 mm tall, standing on its tip | The following object(s) have empty initial layer … | Clean solid; touches the plate at a point | Not sliced |
| Same needle, tree supports on | No error | Clean solid; touches the plate at a point | Sliced with supports |
| Same needle, normal supports on | No error | Clean solid; touches the plate at a point | Sliced with supports |
| Same needle with its bottom 2 mm cut off | No error | Clean solid on a 0.53 mm square base | Sliced |
| 20 mm block exported 2 mm above a 0.05 mm-wide leftover sliver | The following object(s) have empty initial layer … | 2 shells: the block and the sliver | Not sliced |
| Same block and sliver, tree supports on | No error | 2 shells: the block and the sliver | Sliced; the block prints on supports |
| Square pyramid 20 mm across on its tip | No error | Clean solid; touches the plate at a point | Sliced |
What is going on
Bambu Studio checks the first layer when it writes the G-code (source). Before that, it replaces near-empty layers below 1 mm with the nearest good layer (source). That is why a pyramid 20 mm across, standing on its tip, sliced without the error: it is 1.3 mm wide at 1 mm. The 4 mm needle is still thinner than one line at that height, so nothing is filled in.
From the command line the plate fails with exit code 156 and a bare "Errors"; in 02.08.02.61 that exception is raised only by this check. OrcaSlicer has the same check with its own wording, and PrusaSlicer stops with "There is an object with no extrusions in the first layer."
FixSTL showed the needle as a clean solid and the sliver as a second shell under the block; it does not move or delete either.
What was actually wrong
How to fix it
- Look at the bottom of the object in the preview: is it a point, an edge or a separate piece?
- Cut the bottom flat with the Cut tool, or rotate the part onto a flat face.
- Delete a stray piece under the part in your modelling program, or turn on supports so the part prints on them.
- Tree and normal supports both fixed the needle and the sliver in our tests; cutting the bottom flat avoids printing supports.
- Check the file in FixSTL: a small extra shell under the part is the stray piece.
Source: Vendor source code · github.com · Bambu Studio 02.08.02.61 on macOS