So you're looking to have a part mass produced with 3D printing, but you're wondering what that part is going to look like. We're going to go through what many of the standard types of surfaces are for FDM type of 3D printing so that you have an idea of what you might expect and what can be adjusted and changed in order to get just the look that you want for the part that you're making.
Within surfaces, the surfaces of most 3D printed parts are defined by the thickness of the layers. When you're 3D printing a part, you're putting one layer on top of another and building them up over time. And since each one of those layers has thickness, you will end up with a linear type of surface finish, oddly enough. Now, these layers can vary in amounts of thickness. They generally vary between somewhere in 0.1 and 0.3, but they can go larger and they can go a bit smaller. There are layer lines as small as 50 microns, which is the thickness of a human hair. 0.1 millimeters is 100 microns, so two human hairs and then so on from there.
Very often, at Slant 3D, the most common surface finish that we recommend is actually 0.2 millimeter resolution because to the human eye, this looks almost the same as a 0.1, which is twice as long to print and therefore more expensive but still higher quality than a 0.3 layer resolution, which is generally used for draft parts, industrial hardware, things where surface finish or appearance really are not that important. So if you're trying to optimize cost and print time, 0.2 layer height is generally the best way to go.
Now, sometimes you don't want the linear surface finish, you want a 3D print to look like not a 3D print. So how do you get around this? Well, there are smoothing options out there, but generally, we do not recommend post-processing processes because they add to the cost of the part and they limit the amount of scale. Smoothing processes, painting, and other similar processes can all change the surface finish of a part, but they're not ideal because they just cause more problems and more cost. If you design for the process, you can actually get around it. One of the huge advantages of 3D printing is the fact that it's able to apply textures to a part for basically zero cost. With any other type of manufacturing process, adding a subtle texture to the piece can radically change the cost to produce that part, but with 3D printing, it's free. So we might as well use that.
One of the most simple textures that you can apply is actually called a fuzzy feature, which is basically where we introduce a little bit of noise to the outer surface of the part. This process creates kind of wrinkling and vibration throughout it so that each one of the individual layers is actually a different kind of texture and a little bit more noise. So you sort of rough up and apply a small texture to the print. Now, this can be really subtle to where it just kind of makes the layer lines sort of meld into a matte finish, or you can make them really distinct to where the part almost becomes hairy. And there aren't a lot of applicable applications where that's terribly useful outside of areas like toys and some sort of consumer devices, but it can be useful for like filtration if you explicitly want the part to collect particulates and that kind of thing. So that kind of rough surface texture can be useful, and it's also useful in industrial hardware if you're trying to create a high friction surface. So if you're using like a TPU or some type of rubber, you can have the friction of normal rubber, but then you can add that texture and get even more power into it.
If you want something more complex and more distinct like a diamond or knurling or any other sort of pattern, all of those can be created within CAD and within slicers on our side. So there's a number of different methodologies of getting this achieved, and it can create a huge amount of value for your part because again, adding these textures is free. But that's a general summary of what the 3D printing textures are that are out there. You can start with just the original layered look which can be very useful and has a very distinct aesthetic very much like the grain inside of wood. You can design around it and control it in certain ways, or you can attempt to hide it by applying a different texture over the top of that part so that you hide the native layer lines and create something completely original that cannot be manufactured easily with any other sort of method.
Textures are something that 3D printing can actually lean into and create in ways that were never possible before and allow you to create products that could never be created affordably before.