Do you want to print a spacecraft or a part of the Moon? If you’re a beginner, you might want to start with a simpler and/or smaller object that will have fewer potential issues when printing. For example, a very complicated model might have details that could be hard to print on certain models of printers, and it might take a very long time to print (perhaps up to a week!). Complex models and longer print times can sometimes result in the printer failing. If you start with a simple plate to print or a small, basic 3D model to print, the chances of those issues happening are reduced.
This part greatly depends on the software you’re using, what file type you’re starting with, and what you’re trying to print on. It’s always useful to review the 3D or STL file you’d like to print. If you’re working in the free browser-based Tinkercad, you can open your 3D file and verify it looks correct to you. You can remove parts or add a name plate or otherwise adjust as you like it. When you’re ready to finalize, make sure your height is set to zero in the air (so that it’s not floating above the plane – be sure your object is grounded on the work plane as 3D printers don’t often like “floating” objects). Then go to Export in the top right corner and choose the STL file as your output option. You can then drag and drop that STL file to your desktop or drive.
Steps 3 and 4 can be done together in that the printer you choose will affect the materials you can print with and vice versa.
What material will you be printing with? Polylactic Acid (PLA) is the most common material that many commercial printers use. PLA is a biodegradable plastic made from cornstarch and other natural materials so it’s safe to use. There are often numerous colors of PLA to choose from depending on what you have available, so pick a color you like to work with – perhaps you want a green Moon and a red spacecraft, or a gray Moon and white spacecraft.
What kind of 3D printer do you have available to you? It might be an Ultimaker, a Makerbot, a Prusa, a Formlab, etc. Your printer will usually have software to speak with the device. Launch that software, e.g. the Makerbot software, to set your parameters in the next step.
Setting your parameters is usually dependent on the object you’re trying to print, e.g., the size and placement of the print. Once you picked, then do a print preview. The print preview will show you the supports that are needed to print successfully and the estimated time of printing.
This is usually the most fun step! Your object will be printed out layer by layer, which is why it’s called “additive manufacturing”. The size you chose, the complexity of the model, the material you picked, and the speed of the machine will all affect how long it takes to 3D print, from several minutes for small jobs on fast machines to many several hours for larger or more complicated models or slower machines.
For many makers, there is a final step of finishing your model once it’s printed. If you have supports on your print from the printing process, they need to be removed and filed or sanded down. You might want to clean or polish your model a bit. And sometimes makers will hand detail their model by adding silver or gold leaf, painting parts of it, or further customizing. The universe is yours to play with!