"Unable to slice" message

[Delvo]

I was ready to print my first few test objects ever when this happened, so there's no "last known good configuration" to return to because I've never 3D printed before.

The same thing has now happened with two different (virtual) objects. I made my shape in FreeCAD, exported it to STL, opened Cura, opened the file so it's shown on Cura's image of what the print area would look like with my printed object in it, clicked "Slice"... and got this message:

Please review settings and check if your models:
•Fit within the build volume
•Are assigned to an enabled extruder
•Are not all set as modifier meshes

Well, I know it fits because I designed it to and I know the numbers, and the image that Cura is showing me shows that it fits.

But I don't have any idea what "assigning a model to an extruder" could even mean other than making sure the slicer knows what kind of extruder I have. And it came with a list of known printers to choose from including mine (Ender 5 Pro), and I've already told it which one I have, and it's already showing me information on the default hardware such as the nozzle diameter. Suspecting that maybe it just doesn't trust me not to have replaced something with a new part that isn't the Ender 5 Pro default, I also connected it by USB so Cura would have the chance to detect it, and that didn't make a difference. So I guess I'm presuming this one isn't the problem.

That leaves the thing about "setting a model as a modifier mesh". I don't know what a "modifier mesh" is, but I do know that it isn't a choice that came up when I was exporting to STL from FreeCAD, and I haven't seen it as a choice in any of FreeCAD's menus, so I don't have a way to export as not a modifier mesh (or know why this "modifier mesh" thing even exists if it make things unprintable)...

[Delvo]

Hmmm... I see lots of other files types to export to instead of STL, but no sign of which ones Cura will or won't like...

[Delvo]

Hmmm... I see lots of other files types to export to instead of STL, but no sign of which ones Cura will or won't like...

And now I've tried them all and still can't slice anything. Cura's list of file types it claimed to be able to open overlapped with FreeCAD's list of file types it claimed to be able to export as, so I tried all six. Cura wouldn't actually open Collanda DAE, Wavefront OBJ, or X3D. It did open AMF, gITF, and PLY, but, as soon as I clicked "Slice", all three of those gave me the same message as STL, with the same three non-explanations. So Cura doesn't approve of any of the ways I can possibly export a project from FreeCAD!

[Delvo]

Well, I've found the cause, so now the only question is what to do about it. I can slice small objects without any trouble, but not my biggest. I designed something almost to the full length & width of the stated printable volume (220mm apiece because this is an Ender 5 Pro; the object is about 216.9mm long & wide), and Cura has default margins of 15mm at all four edges that it refuses to use, making the printable area 30mm shorter in both horizontal directions than it's supposed to be.

I don't see a way to turn that off, but I do see a way to lie to Cura and claim it's really 250mm long & wide so it'll let me have back the area it stole and actually use the 220mm I'm supposed to be able to use. But I don't know how everything will react to that. I'll do a short test object as soon as possible. If that doesn't do it and there's no way to just turn the margin off, I'll have no choice but to redesign the object, which would be very irritating.

(...and then console myself about the purchase of a larger-than-average printer and not getting to use its claimed size with the knowledge that a smaller one would still have the same issue anyway.)

[curious aardvark]

dump cura and try prusaslicer instead.

Not sure why you would want unuseable 'margins'.
usually the defined build volume is also the printable area.

Also check that you haven't got any pre-extrusion lines or outlines that are outside the build volume due to the size of the model.

I've been caught out by that in the past.
I usually have my filament prep outlines 3mm from the model.
Causes problems on the rare occasions i try to use the fulll build plate width.

[DanJustDan]

I ran into this a few days ago on one of my first prints. Turns out the skirt was falling outside of the printable surface. Turn that off in the settings and you may be good to go.

Heh. New guy should probably look at the post dates...