Maybe you've printed something that has great bones, but you imagined a finished project with fine details and a different aesthetic than you currently have on your new 3D print. While you may be tempted to start directly to alter the appearance of your print, there are a few essential steps for post-processing 3D prints you should apply before you begin with the finishing touches. Not only will these methods provide a good base so that you can seamlessly apply the finer details, but they can also improve your print's strength and overall post-process quality.
Let's take a deeper look at cleaning up 3D prints to prepare them for finishing.
Removing Supports
If your print has insoluble supports (made of the same material as the central part), you must remove them manually. Often it will be possible to snap the supports off with your fingers, but if they are in a difficult-to-reach spot, try employing a pair of needle nose pliers to cut them away.
Soluble supports, on the other hand, may be simply dissolved, leaving virtually no trace of where they once were present. The two most-used soluble support materials are HIPS and PVA for those fortunate enough to use a dual-extruder 3D printer. PVA works great for PLA prints and dissolves readily in water. Likewise, d-limonene dissolves HIPS, which is your go-to choice for ABS.
Sanding
There are a few crucial points to remember when you're first learning how to smooth out 3D prints. First, sanding resin prints is the best way to prepare for later painting and polishing printed components, and although it can take some time, the finished product you will gain will be well worth the labor involved in 3D print smoothing.
First, use circular movements with lower-grit sandpaper (150-400) to start. Next, make several passes over the surface you are smoothing, using finer-grit sandpaper (up to 2,000) each time. The circular motion is critical with FDM parts because a back-and-forth motion could damage the appearance of the visible layers.
If your print has fine details or heat-sensitive filaments, use water to absorb any heat you generate with the sanding. Just dip the part in water and sand as before. This will prevent damage and keep the part cool.
Welding
In your journey to creating larger, complex objects using ABS, welding with acetone is a sturdy and inexpensive method for joining multiple ABS parts. This is a great and straightforward workaround when your printer's build volume is limited.
Apply a small dab of acetone onto one of the parts you want to attach. Use sparingly, or the entire part can be damaged or ruined.
The plastic will melt briefly, and you can attach the other part securely by holding them together for a few moments to let them set.
This method only works with ABS, and the weld will always be the weak link in your object, but this is an inexpensive and easy solution to keep in mind for your projects.
Gluing
If you use materials other than ABS for your prints, glue such as super glue or products like 3D Gloop! are easy to use for the same purpose as acetone welding. When finishing PLA prints or PETG prints, glue works very well to get around the size constraints of your printer.
Now your print is ready for the final touches of finishing! The extra time spent on the techniques described in this article will be visible in the excellent quality of your finished print.