When printing 3D figures, filament or plastic is melted and extruded from your printer’s heated nozzle. The extruded filament will gradually be formed into your desired object on a print bed. These print beds, or build surfaces, are also heated.
3D printers have heated beds because the heat allows for better control of the cooling process, which contributes to the quality of the 3D print. It improves the adhesion of the first layer and keeps it warp-free. Heat also helps make the first layer an ideal foundation for the rest of your 3D object.
In this article, we will talk about the various reasons why a heated bed is essential for 3D printing. You will also gain insight into what happens if you print an object and don’t use a heated bed.
Reasons Why 3D Printers Have Heated Beds
Here are the main reasons 3D printers have heated beds:
1. To Keep the Material From Warping
Heat in your 3D printer’s nozzle or extruder allows it to easily squeeze out the melted plastic material or filament onto the build plate or the bed. A heated bed, meanwhile, keeps the extruded material warm, and this, in turn, will help prevent warping.
Warping happens when the plastic on the outer part of your print cools down at a different or uneven rate compared to the rest of the material. When the corners of your print warp or lift, your 3D model gets deformed.
Check out this video demonstrating what happens when your print warps:
A heated bed prevents warping by keeping the extruded material at or over heat-deflection temperature throughout the entire printing process. Heat-deflection temperature is the range of temperature at which a material is malleable and therefore remains flat on the build surface.
2. To Reduce Stress on Your Material
FDM 3D printers extrude melted plastic at a temperature that is hot enough to allow it to flow from the nozzle. However, the temperature should also be low enough to allow the plastic to cool and harden predictably. But if the filament cools too rapidly or if the extruded plastic reaches a too low temperature, it contracts, and it experiences internal stresses build-up. This, then, compromises the quality of your print.
After all, 3D printing uses plastics or polymers, and these materials are primarily amorphous, which means they lack a clearly defined form or shape. They are also called non-crystalline solids because they don’t have the long-range order of a crystal. These materials get hard and brittle when they are exposed to low temperatures.
A heated bed helps with this problem by retaining the temperature of your 3D printing area to help with the optimum performance of your material. With a heated bed, your filament will take more time to cool down, and this would reduce stress on the material.
As such, increasing the temperature of the material changes its state from amorphous to viscous and rubbery, making them soft and more ductile. Increasing the temperature also increases the expansion of the material as it allows polymer chains to move easily when the strength of intermolecular forces is lessened.
Therefore, a heated bed helps provide the ideal temperature for such molecular transition, which is also known as the glass transition temperature.
The glass transition temperature helps reduce the difference in stress between your 3D object and the print bed.
3. To Improve Adhesion of First Layer
Getting a 3D printer with a heated bed helps the first layer of your print to stick or adhere better. Without proper adhesion, the extruded material could cling to the printer’s nozzle instead of staying down on the build plate and providing a stable foundation for the other layers. Your print will look like a stringy clump of plastic and not the 3D object you planned and expected to get.
This adhesion issue is also associated with warping. Without heat on your build plate, your material will cool down, and the corners of your first layer will start to curl and lift up from the bed.
Among the different 3D printing materials, ABS is the most notorious when it comes to warping and getting deformed. ABS would be hard to get away without a heated bed because it is so sensitive. Moreover, since 3D printers have smooth print surfaces or beds, the filament or material could still slide rather than stick.
Using a heated build plate reduces the chances of your material sliding and gives it an optimal level of adhesion. The explanation goes back to the glass transition temperature, where plastics become more rubber-like and therefore stick to surfaces more easily.
However, using a heated build surface is just one way for you to improve adhesion. There are other things you could do to help your material stick to the print bed. You can check out other tips in this video:
4. To Remove Finished 3D Prints More Easily
While a heated bed makes it easy for your 3D print to stick firmly to the surface, it also makes it easy for you to remove the object when it is finished printing.
How tough your print is to remove might depend on the kind of plastic or material you are using and the size of the object, but generally, the task of removing a 3D object from the build surface is something a lot of people struggle with.
A heated bed, however, helps ensure that your bottom layer is smooth and clean. Because of this, your print will easily and quickly pop right off its build plate once it has cooled down and hardened.
All you need to do is make sure your print bed has completely cooled down before trying to take off the object from the surface.
A lot of 3D printers nowadays come with heated beds. This is an important feature because it helps avoid a lot of potential problems during the printing process, including warping and lack of adhesion. After printing, a heated bed also helps make it easy for you to remove your finished model.
Because a heated build surface helps prevent many issues and ensures strong, durable, and high-quality prints, it also makes things a lot more convenient and cost-efficient on your part. The more successful prints you have, the more savings you get in terms of time, energy, and money.