Layer lines are an unavoidable feature of FDM 3D printing. Learn smoothing 3D prints and hide wrinkles with our essential guide to PLA smoothing!
Some individuals adore the 3D printed texture, while others despise it. However, there are various reasons why you might want to “finish” a print. It could be a display piece or anything that requires a smooth surface to prevent friction between moving elements.
PLA is the most prevalent FDM 3D printing material; thus, it is essential to post-process it. Unfortunately, due to the nature of the material, smoothing 3D prints with acetone isn’t a possibility (as shown in the image above). Still, there are alternative options for achieving a smooth and polished surface.
We’ll walk you through some of the numerous ways to smooth up and finish your PLA prints in this article. We’ll start with the fundamentals of trimming and sanding before moving on to various coating methods or even melting a part’s surface for a flawless finish.
Smoothing 3D Prints: 5 Simple Ways To Make Smooth PLA Getting Rid of Extra Material
Excess material, such as brim edges or supports, may be present in print, and they must be removed before they can be completely finished. There are a few various tools that you can utilize to accomplish this.
Knife for everyday use
Let’s start with the basics: trimming superfluous material with a craft knife. An X-Acto knife is an excellent example of this type of instrument. If you’ve done any other DIY projects, you’re probably already familiar with this knife.
When looking for a knife to clean up your 3D prints, the blade is the first thing to think about. The average size 11 blade is an excellent choice in general because of its adaptability, but others may be more suited to your needs.
Before you begin cutting:
- Remember to follow the fundamental knife safety guidelines.
- Always keep your distance from yourself.
- While holding the print, be careful not to put your fingers in front of the blade.
- When you’re missing, don’t use too much force.
Place the blade on one of the print’s edges and move it across it to remove supports or other superfluous material; don’t use too much pressure, or you’ll risk removing more material than you wanted and damaging the print. This should be done until the edges are smooth.
Finally, a single-edged razor blade would suffice if you don’t have access to a utility knife; however, exercise caution!
Dremels and other rotary multitools are other excellent alternatives for completing 3D printing. These tools are used are very similar to how a knife is used. Nonetheless, the variety of bits available allows you to finish the interior corners and other difficult-to-reach areas of a part more quickly.
When utilizing a rotary multitool, there are two things to bear in mind. To begin with, they are speed tools rather than torque tools. When you don’t get the results you want, raise the rotational speed instead of exerting more pressure. This will save you a great deal of time and extend the life of your tool.
Second, because you’re working with plastic and a power tool, don’t hover over one location for too long or exert too much pressure. Because the device’s movement generates heat, doing so will very certainly melt the plastic in the area where you’re working, resulting in divots and holes in the print.
Some rotary tools include sanding attachments, although these can be too harsh for smoothing 3D print PLA. Next, we’ll look at how to sand effectively.
Smoothing 3D Prints: 5 Simple Ways To Make Smooth PLA 1. Sanding
Sanding is one of the more accessible means of smoothing 3d prints, and as you may have discovered from your experiments, there are a variety of ways to do it.
If your print has a lot of huge surfaces, you might wish to use a sanding block. They relieve stress on your hands and ensure that the sandpaper and your print wear evenly.
Nail files are your best bet if you have a print with a lot of detail. There are a variety of sizes and types of nail files, and the best one for you will depend on what you’re sanding, although cheap cardboard files can typically suffice.
Of course, loose sheets of sandpaper can be used, and in some cases, this may be preferable. Move the sandpaper across the print in circular motions against the grain of the layer lines to receive the best results from your sanding efforts.
You’ll also want to increase the grains of your sandpaper. Depending on the outcome you want, you might start with 400-grain sandpaper and work your way up to 4,000 grit.
Finally, you’ve most likely heard about wet sanding. Wet sandpaper is used in the same way as conventional sandpaper, with the exception that you must wet it every now and then. Because it doesn’t remove a lot of material and leaves a polished finish, high-grit wet sandpaper can be used as the final sanding stage.
Smoothing 3D Prints: 5 Simple Ways To Make Smooth PLA2. Smoothing 3D Print with Heat Gun
As you may know, PLA is not particularly heat resistant, making it unsuitable for outdoor use. However, it does imply that you can use the heat’s effect on the plastic to finish your prints.
Placing the print on a turntable and turning it slowly to uniformly disperse the heat produces the best, most consistent results. This also helps avoid over-melting any specific sections, resulting in a better overall outcome. A heat gun set to the lowest heat setting is the most regularly utilized equipment for this purpose.
While a hairdryer may appear to be an excellent alternative to a heat gun, it isn’t designed to be hot enough to melt plastic (most models don’t even reach PLA’s glass transition temperature of 60 °C). So you’ll have to wait a long time to see any results!
Smoothing 3D Prints: 5 Simple Ways To Make Smooth PLA3. The coating on the surface
Whether sprayed, painted, or dipped, a coating of material is another approach to generate a smooth surface on a print. This can fix surface texture flaws, such as layer lines and provide a gleaming, smooth finish. A paint primer or an epoxy coating are two common PLA examples.
Sanding and using a primer on a print are almost synonymous. The purpose of using a primer to finish your print is to fill in the layer lines and create a smooth surface. When that, you sand the top layer down after the primer has dried. Because the primer is much softer than the PLA, sanding the primer is usually easier than sanding the PLA.
A print that has been primed usually looks much finer than one that has been sanded. You should keep in mind, though, that this method takes a lot longer because you’ll have to wait for each layer of primer to dry. Additionally, it’s better to paint over a primed print because primer alone won’t hold up over time if left uncovered.
Epoxy is a resin covering that functions similarly to primer. Epoxy outperforms primers in filling more significant gaps or printing artifacts left behind by the printing process. It is, however, a little more challenging to work with because you must mix it before applying it to your print.
To finish your print using epoxy, prepare a batch of epoxy resin. Then, using a paintbrush, liberally apply it to all surfaces of your print. Just make sure your coats are even, so your end print doesn’t have varied thicknesses.
Smoothing 3D Prints: 5 Simple Ways To Make Smooth PLA 4. Spot Putty and Bondo Glazing
Bondo Glazing is well-known for its long lifespan and ease of application. It’s rapid and doesn’t show any symptoms of shrinking. It produces a completely smooth finish, ideal for filling seams and holes in 3D printing.
There’s no need to mix it or do any other labor because it’s ready to use right out of the tube.
It has a 3-minute working time and can be sanded in less than 30 minutes. It’s non-staining, which means your 3D prints won’t be harmed, and their color won’t be ruined.
It is recommended to work in an open space or a well-ventilated area. Because it is known to create significant fumes and odor until the product is dry.
The following are some of the advantages and features:
- Simple to Use
- There is no need to mix anything.
- In 30 minutes, you’ll be able to sand it.
- Quickly dries
- Shrinkage is minimal.
After it cures, it sands beautifully, and it’s a good idea to apply at least a layer of primer before painting over your models.
Smoothing 3D Prints: 5 Simple Ways To Make Smooth PLA5. Smoothing with chemicals
Finally, we’ll discuss chemicals. Although PLA cannot be smoothed with acetone in the same manner as ABS, there is still a way to get similar quality.
Polymaker Polysmooth is made of PVB, a material that can be chemically smoothed and is quite similar to PLA. It does, however, necessitate the use of a Polymaker Polysher. Isopropyl alcohol is dispersed in this box, reacting with the filament to smooth the top layers.
Although purchasing everything needed is an expense, if you require a significant number of smooth prints, it may be worthwhile to take the plunge and set up this system.