Slicer model orientation


#1

Ok, I've tried to get Octoprint to slice an stl file and the first one I tried worked terrific. The second one, not so great.
When selecting and uploading a file to be sliced and printed, how do you make sure the orientation of the model is in the correct orientation to be successfully printed?


#2

My first several models—as designed in Autodesk Fusion 360—were using the wrong plane. To me, the one that looked like it was "down" seemed to be the XY plane but I was wrong. If you select the XY plane from the object viewer to the left by its name "XY", you'd see that it's not the intuitive one.

As a result of this, all of my initial designs landed in Cura in the wrong orientation and I always needed to rotate them.

If you're trying to use the embedded Cura and you're not sure about the part orientation in the STL, then I might suggest bringing it into the application version of Cura and then slicing it there. You'd then upload the gcode file to OctoPrint and life would be good. In fact, the latest version of Cura has really awesome features and you might benefit from exercising some of those.


#3

As @OutsourcedGuru noted, there are a lot of more advanced features in the current version of Cura which runs on desktop/laptop computers. The version bundeled with OctoPrint is really showing its age.

If you are designing your own objects, you can also use whatever program you are designing in to rotate the object to the orientation you desire prior to exporting it as an STL.

If you do need to slice from withing OctoPrint (as I did when helping out a local elementary school where their ChromeBooks and ancient laptops would not run Cura), the Full Featured Slicer plugin was a must have. It gives you a graphical representation of what is on the print bed and allows you to rotate and scale what ever you have put on the bed. It includes a "lay flat" command - very helpful, since you often can not tell easily by eye if you've got the flat face oriented exactly downward). You can also add multiple STLs to the print bed and position them where you want.

One of the best features of the full featured slicer is that it allows you to tweak a number of the settings (bed and tool head temp, layer height, infill %, flow rate, & etc.), so you don't have to make and store and import into OctoPrint a separate profile for every minor variation you wish to use.

As much as I like what the Full Featured Slicer adds to slicing from within OctoPrint, I've gotten to the point where I slice in a more recent version of Cura on my laptop computer and send the gcode to OctoPrint, unless I'm faced with a situation like at the school, where I had no choice.


#4

As has been already pointed out, avoid using the slicer bundled with OctoPrint if you can. There are numerous free slicers available for your desktop (or even cloud based) with features above and beyond what is available for use through OctoPrint.

Once you start a print with OctoPrint, using the Raspberry Pi for other CPU intensive tasks like slicing may have a negative effect on the quality of the print. I'm often printing one object while I'm preparing the next object to be printed on my desktop.

Once you have the full features of a desktop (or cloud) slicer, determining the best orientation for an .stl file becomes much easier. The slicer will be able to rotate the object into the best orientation in some cases, automagically!

The best orientation for an .stl file is usually the orientation that minimizes or eliminates the support structure necessary for a successful print. Most slicers will show you the parts of an object that need support visually making it fairly easy to change the orientation and see the best one.