What is Slicing in 3D Printing?

When it comes to 3D printing anything, you have to design your product or object using a CAD software. You create the product to your desired specifications. After that, your CAD drawing needs to be sliced, using your preferred slicing software.

What is Slicing in 3D Printing?

In this article, we will be going through what is slicing in 3D printing.

What is Slicing?

Slicing is a piece of software that everyone uses when creating objects and products on a 3D printer. The software gives the printer a path to follow.

The slicing software takes your image and converts it into G codes that your 3D printer can understand. These G codes are a type of instruction on how the printer needs to print your design.

Like the name suggests, your image is taken and turned into G codes. After that your image is printed in layers.

These codes have sliced through your image to create layers that the printer can follow. Alongside this, the instructions created can also include the layer height that is needed.

Slicing cuts your object into many 2D layers that will be printed one at a time to create your 3D product.

Slicing Requirements

3D objects can be created using a wide range of CAD softwares like Blender and SolidWorks. However, most slicers can’t process a wide range of formats. That is why it is best to use the file format of STL (.stl) when exporting your 3D product drawing to be printed.

Once the product is in a format that the slicer can understand, the next step is to give the slicer all the details that it needs.

These details include the layer height that you require, speed and part positioning. You can slightly alter your design. Dimensions can be changed through the scaling feature. While parts can also be partially or completely hollowing or infilled with a pattern.

Once in the slicing application, the support structure is enabled which is a very practical feature of a 3D slicer. Without a support structure your product won’t have any strength and wouldn’t be able to hold its shape for long.

Slicing Settings

As mentioned above, there are a few features with slicing software that really help make your product look as good as you want it to be. The following settings are found on all slicing software:

Layer Height

The layer height setting is very important, as the number you place in that box will determine the height of every layer of your design. Which will then affect the overall size and height of your product.

You can print thin layers, this will then result in more detailed prints with a much more smoother surface. However, the thinner the layer the longer the printer will take to print the overall object as there will be more layers to print overall.

If you are printing something that doesn’t have any details, then thicker layers may be better. However thicker layers might be faster yet the individual layers will be more visible and the surface of your object will look rough.

Shell Thickness

This refers to the number of times the outer layer walls of your model are traced by the 3D printer. This defines the thickness of your side walls which then determines the strength of your overall model.

Thicker walls increase the strength and durability of your product. However, normally the number your settings come on is perfect.

Although if you want a more durable product you can increase the number. Yet, this does depend on the type of product that you are printing.


Retraction tells the printer is used a lot with FMD slicing. This setting tells the printer to pull the filament back from the nozzle and to stop releasing filament.

Retraction is normally always enabled, and it is your choice if you want to turn it off. Sometimes this setting can cause the filament to become clogged up which could then affect your printed design.

Infill Density

Infill is a really important setting, which helps give your product strength. This setting is normally measured in % rather than mm. If your printed object has 100% infill, that means your object will be completely solid on the inside. The higher the percentage of infill the stronger but heavier your object will become.

This setting does depend on what you are creating. If your printed object is for display purposes then it doesn’t need to be completely filled in. While if your object is for use and will deal with pressure then it will need a higher infill density.


There is a setting if your object needs any kind of support. As models are printed in layers, sometimes some parts of the design don’t have a layer to be built onto.

There are two support type settings to choose from.

Touching building plate is where a section of your design needs support and can attach to the building plate.

The other support setting is called everywhere. This is for much more complex designs, where a layer of the design overhangs in an area that can’t attach to a support coming from the building plate.

FMD Slicing

FMD (Fused Deposition Modelling) uses a print head which uses a printing head that moves in two different directions. It moves across the X and Y axis, while a plastic filament is melted and pulled to create a 2D layer. This process is then repeated until all the 2D layers have been completed and your 3D object has been created.

A FMD printer is all about the movement to help build your 3D design. Once you are happy with your design and all the printing settings have been set, the slicer will process all the information that you have given them. The G codes are then uploaded to the printer, which will then create your desired 3D object.

SLA Slicing

What is Slicing in 3D Printing?

SLA (Stereolithography) uses UV light to cure and solidify liquid resin into its layers. Once a layer has been solidified, the building platform will lower and allow fresh resin to fill and form the next layer. This process will continue until the 3D model has been created in entirety.

SLA printing doesn’t require as much movement compared to FMD. The main difference between FMD slicing and SLA slicing, is that SLA slicing doesn’t use G codes. Most desktop SLA printers use their own formatting and their own slicing software.

Slicing for SLA products, includes settings of exposure time and lifting speeds alongside the common layer height and support structure seen in other slicing software.

Slicing Software Programmes

A slicing software is essential for any kind of 3D printing and you need one to actually be able to print your products and models. Slicing software ranges in price from free to a couple thousand dollars. Some 3D printers come with slicing software already.

However, it is worth noting that some 3D printers have particular slicing software that it is compatible with.

You are free to choose whichever slicing software you would like, but some printers are designed to only work with particular slicing software for various reasons. The main one being the more complex designs and products you are designing a more complex and robust slicing software you need.

Below are a couple of recommended slicing software programs that you can use:

  • Cura
  • Simplify3D
  • IdeaMaker
  • SuperSlice
  • PreForm
  • Slic3r

Final Thoughts

Slicing is an important part of 3D printing. It is a software that is used every time you use your 3D printer, which turns your design into G codes and then creates the instructions for your printer to follow. Your 3D printer will then begin to print your design in 2D layers until the product is complete.

No 3D printer can really work without this software and there is a vast range of slicing software available for you to choose from.

Michael Moore