Once you have your STL, you must prepare it in a slicer program. This is a piece of software that will turn your 3D shape into instructions that the 3D printer can understand.
Almost all of the self-service printers in the Innovation Lab are Prusa MK4 machines, which use a program called PrusaSlicer. This page will walk you through how to prepare a print in PrusaSlicer, then briefly discuss the exceptions for other printers at the end.
There are a couple of ways to get files into PrusaSlicer
You can put multiple items onto the build plate at once. By default they will all be overlapping with each other at the center of the build plate, but you can click each on individually to move them out of each other's way.
The toolbar to the left of the window features tools for rearranging, resizing, and even bisecting your model. You can also set your model's absolute size and position by clicking on it and using the Object Manipulation fields in the bottom right corner.
The move, scale, and rotate features should be fairly easy to use. You can consult the Prusa Knowledge Base for more details on them.
The left toolbar also features a few more advanced features.
The Place on Face tool will highlight a number of external planes that you may want to put in contact with the build plate. This is handy for quickly orientating complex objects in optimal configurations.
The Cut tool allows you to cut an object into two parts, automatically arranging the cut surfaces against the build plate. This is useful for exceptionally complex objects that have no good flat surfaces to naturally touch the build plate with. After printing a bisected print, you can join the two halves using superglue or hot glue provided in the lab's red toolchest.
This feature can also be used to chop off features of an STL that you don't want to print at all.
The other feature on the left toolbar is Paint On Supports. Entering this mode allows you to paint on parts of the object that you want to be sure are supported - since 3D prints build up layer by layer, and part that overhangs too far will need additional supports underneath to hold it up.
When using the Support Painter, make sure that your Supports setting in the upper righthand corner is set to For support enforcers only.
The Prusa Knowledge Base has in-depth documentation about all the various support features.
The most basic and important print settings are set in the menus at the top right of PrusaSlicer.
Once your settings are set, you can preview your G-code file by clicking Slice now in the bottom right corner. The program will determine all the moves the printer will have to make in order to create your model. For complex models this may take up to a few minutes.
Once the G-code is generated, you will automatically enter Preview Mode. Instead of a solid model, you will now see all the lines that will make it up, color coded to correspond to the type of feature being shown. A box in the top left will tell you how long your print will take.
A dialog box in the bottom right will warn you of any stability issues that the program thinks you should know about. Most of these can safely be ignored, but if your print has problems they should be the first thing you investigate for the second attempt.
A red background in preview mode indicates a critical error, such as a model that extends beyond the edge of the build plate. If this is the case, or if you see any other feature not to your liking (support not where you want it, brims not touching, etc.), you can go back into 3D Editor view by clicking the solid cube in the bottom left corner to make adjustments before slicing again.
Some specialized prints may not be suited to just any printer. If your print is any of the following, please consult an Innovation Lab employee either in person or through the Consultation Form.