What we tested
| File | OrcaSlicer said | Actual problem | Result |
|---|---|---|---|
| Square pyramid 20 mm across, 15 mm tall, standing on its tip | One object has an empty first layer … | Clean solid; touches the plate at a point | Not sliced |
| Square pyramid 4 mm across on its tip | One object has an empty first layer … | Clean solid; touches the plate at a point | Not sliced |
| Same 4 mm pyramid, tree supports on | No error | Clean solid; touches the plate at a point | Sliced with supports |
| Same 4 mm pyramid, normal supports on | No error | Clean solid; touches the plate at a point | Sliced with supports |
| Same 4 mm pyramid 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 | One object has an empty first 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 |
What is going on
OrcaSlicer checks the first layer when it writes the G-code (source). Up to 2.3.1 the message read "One object has empty initial layer and can't be printed. Please Cut the bottom or enable supports." (source).
OrcaSlicer 2.4.2 refused the 20 mm pyramid on its tip, which Bambu Studio 02.08.02.61 sliced. From the command line the plate fails with exit code 156 and a bare "Errors"; in 2.4.2 that exception is raised only by this check.
FixSTL showed the pyramids as clean solids 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 · OrcaSlicer 2.4.2 on macOS