Cura stops at "preparing to slice..."

[worker72]

Yesterday downloaded and installed Cura 2.1.2. Sliced an object, and printed it fine.
Today, I want to slice a similar object (my next iteration), but Cura hangs at "preparing to slice".

Cura 2.1.2
Windows 10

Engine log:
Calling engine with: ['C:\Program Files\Cura 2.1\CuraEngine.exe', 'connect', '127.0.0.1:49674', '-j', 'C:\Program Files\Cura 2.1\resources\machines\ultimaker_original_plus.json', '-vv']

[worker72]

After restarting Cura, slicing worked ok.

[Ghostkeeper]

We've had reports where this only happens the first time after installation or after deleting your settings.

It's still a bit fickle though. For me it seems to happen only with very computationally-heavy objects.

[PrinterMan]

I noticed that the print bed size has shrunk with the last 2 versions and this is the reason that its hanging on preparing to slice. What is up with the print size shrinking?

[fieldOfView]

You mean in height? Check the print-sequence setting, it it probably set to "One at a time". Try setting it to "All at once".
The height is limited in "One at a time" mode because otherwise the printhead or gantry could collide with a previous object within the job.

[luukakkerman]

I have encountered the hanging at 'preparing to slice' now multiple times over the last weeks with Cura 2.1.0-
Indeed, restarting the program works to get at least the model slicing when importing again. Sometimes moving, scaling, changing print settings and doing all action in general less quickly looks to solve this. But some models (and no, they are not complicated at all but very basic geometrical models) seem to activate this hang bug every time.

As I see 2.1.2 is out, I will try this release now to see if it helps.

[nickthetait]

If you run into a model that is able to consistently trigger this bug please post it here.

[johnwebbcole]

The peg and collar from http://www.thingiverse.com/thing:716747 will both hit this when scaling is turned off, or if its on (and it always resizes these) and you remove the object transformations. 1.5.4 seems ok with both of them.

I'm on 2.1.2 on macOS 10.11.5

[universam1]

What does help for me is to run "Center Object on Platform" for to get it starting.
Hope that helps

[Ghostkeeper]

Basically the workaround is to trigger a reslice then.

We've seen this issue come up from time to time, even currently on 2.1.99.

[baltuonis]

For me slicing stops when I have more objects (like 5 or more) and when I'm changing "PRINT SEQUENCE" parameter a lot of the times the slicing does not react and despite me changing all the other parameters slicer does not "reslice" the objects.

Cura 2.1.2 64bit
Windows 10

[cottmann]

Same here. Cura 2.1.2 on Windows 7 and Ubuntu 14.04 hangs at "preparing to slice...".
Using CuraEngine via the command line works (Ubuntu).

Seems to be connected to the model size.

• The one that fails is 18.3 cm long, which means it fits my Prusa (20x20), but reaches into the shaded area that Cura draws on the edges of the build plate. When I rotate the model and keep clear of the shaded area everything works fine.
• It also hangs when I take a smaller model and drag it into the shaded area.

So it looks like Cura introduces a margin to the print bed. Can that be changed?

[Ghostkeeper]

Yes, the margin is the width of the brim or skirt. You can reduce the brim width or skirt radius to reduce that margin (but your brim will be smaller).

[Ghostkeeper]

In 2.1.2 when it can't fit the models on the plate due to the disallowed areas of one-at-a-time printing, it gets stuck on Preparing to Slice... That one is known to us. It seems different from what worker72, PrinterMan and luukakkerman had though.

[cottmann]

Thank you for clarifying, @Ghostkeeper. I clearly overlooked the brim.
And thank you for a great piece of software!

[awhiemstra]

In 2.1.2 when it can't fit the models on the plate due to the disallowed areas of one-at-a-time printing, it gets stuck on Preparing to Slice... That one is known to us. It seems different from what worker72, PrinterMan and luukakkerman had though.

Also, in 2.2 it will provide a clearer indication of this behaviour.

[thopiekar]

I guess it has been fixed now..