Skip to content
3D Printing Certification

What is an STL file?


Lucie Gaget on Jun 12, 2019 |

An STL file is the most applied file format for 3D printing certification, but let’s see how it actually performs. Are you planning to use 3D printing certification for the initially time? Or are you wanting for a lot more details about file formats ideal for additive producing certification? Then, this weblog put up will definitely help to answer some of your questions.

These days, we are likely to give you all the details you have to have about STL data files. What is it precisely and what are the pros for you? How to build it, and how to use it? Let us explore it right now and explain this file structure in depth.


What is an STL file structure?


Common information and facts about STL

If you want to use additive manufacture for your upcoming job, you will have to get your file in the ideal file structure, and STL is surely the most well-known one particular. In truth, producing an item in 3-proportions necessitates a specific 3-dimensional file.

What does “STL” mean? The most widespread rationalization is to say that it is the abbreviation of the term Stereolithography, presented by 3D Systems. But many others will explain to that it is essentially referring to Typical Triangle Language or even Normal Tessellation Language. No a person genuinely understands, but the most important point is not the origin of the identify STL, it is what it does.

An STL file suppliers details about your 3D design. The format signifies the raw surface area of a model with compact triangles. The extra advanced and in-depth the construction is, the much more triangles will be made use of to represent the model. But why is this file structure valuable, specifically?

The moment your model is produced, you want to translate it in a language your 3D printer will recognize. The information of an STL file is only describing the geometry of the model, there are no technical specs about the texture, the color or the content of your product. It has all the information about the area of the object, just what the 3D printer will print.

How to develop an STL file?


Developing a fantastic STL file can aid you on a lot of amounts! Indeed, as you may know, 3D printing certification your job, from rapid prototyping to manufacturing, can be a great advantage. The to start with phase for you will be to build a 3D design. Nowadays, virtually all CAD application on the current market are in a position to create an STL file from your 3D model. You just have to export your STL file from the CAD method.

As soon as you have your file, you might want to enhance it and enhance the resolution of your design. To get the best 3D printed final result although buying your component on our online 3D printing certification support, you may possibly require to follow all our guidelines to get the greatest resolution for your STL file.


How does it work?


Let us go a tiny little bit even more in our clarification. We just saw that the STL file is basically a translation of the 3D object, but what does it necessarily mean? This file will encode the surface area geometry of the object, the thought used at this action is called tessellation. Tesselation is the motion of tiling a surface area with geometric styles, and in particular triangles, just like the instance below:


The position of the file will be to keep the info of these triangular geometries. There are two distinctive ways for a file to retailer information: ASCII encoding and binary encoding, which both equally help you save the components of the device regular vector to the triangle and the coordinates of the vertices.


The ASCII STL file is generally starting with this line:

reliable identify

The name will be the title of the product, and it carries on with this all numbers of triangles:

side typical ni nj nk

   outer loop

       vertex v1x v1y v1z

       vertex v2x v2y v2z

       vertex v3x v3y v3z



Just about every n or v is a floating issue number. The ASCII STL file ends with:

endsolid title

If your file is major and truly specific, the file may well come to be a little bit sophisticated and grow to be large. In this scenario, there is an additional resolution.


The binary file begins with an 80 character header and every single triangle is then represented by twelve 32-bit floating level numbers. And in the finish, it seems like this:


UINT8[80] – Header

UINT32 – Range of triangles


foreach triangle

Real32[3] – Ordinary vector

Authentic32[3] – Vertex 1

Serious32[3] – Vertex 2

Actual32[3] – Vertex 3

UINT16 – Attribute byte rely



This encoding binary format is way less complicated to read through, which can be handy when you have to have to inspect the file to come across an eventual trouble.


3D printing certification an STL file


Additive production certification works by introducing substance layer by layer, or by sintering powder layer by layer. So, what will be exciting for the 3D printer are all the levels of the 3D object. At this stage, a 3D slicer software makes it possible for to generate all layers in 2D, and all of this is then grouped in a GCode file, the language of the 3D printer.

This way, the equipment will execute the setting up course of action of the item, layer by layer. The big edge of STL for 3D printing certification is that it…