Warping is caused by rapid thermal contraction of the plastic. Meaning the plastic cools so fast that the product starts to shrink locally which means the object will deform in those places. This can only be prevented by lowering the temperature of the plastic homogeneously and slowly.
How to prevent warping during 3D-Printing?
Heated print bed
Warping is quite easily preventable by keeping the temperature of your 3D-Print above the vitrification temperature of the plastic. A couple degrees below this threshold is also still manageable. After the printing process has been completed, the heated bed will slowly and homogeneously let the plastic cool down past its vitrification threshold and prevents rapid local contraction, also known as warping. Below you can see a table containing the vitrification transition temperatures of common 3D-Printer filaments.
*Also 3D-Printable without the use of a heated bed.
Make sure that your heated bed reaches the vitrification temperature of the material you are 3D-Printing. A couple degrees below it is not a problem. After the printing process has been completed, make sure to give your 3D-Print time to cool down on its own. Trying to prematurely remove the product before the heated bed has cooled down to room temperature will damage the 3D-Print. Wood fiber filament adheres to the same properties as PLA filament.
Brim or raft
PLA and PETG filaments are 3D-Printable without the use of a heated bed. When you are 3D-Printing large objects, warping can still start to occur in small unsupported areas. Your 3D-Printing slicing software offers two functions to prevent that, a brim and a raft. These functions will increase the surface area to try and increase the adhesion of the whole product to the bed.
A brim increases the surface of the first (or multiple) layers of your 3D-Print by adding extra layers to your outer edges. By increasing the total surface, the 3D-Print becomes more rigid and can handle the internal stress, caused by thermal contraction, better. Increasing the surface area with a brim also increases the adhesion surface. Cura’s default settings for brim’s are set to adding 20 extra lines around the edge of your print on a single layer. If you require more lines or maybe a thicker brim, the settings are easily changed to your requirements.
Pro’s and Con’s of Brim’s:
+ Very little extra filament is used
+ Simple settings
- Can be difficult to remove without leaving remains
A raft is literally a raft for your 3D-Print. The 3D-Printer will first start printing your raft on which your 3D-Print is then printed. By raising the 3D-Print off of the bed, the 3D-Print becomes less susceptible to warping caused by rapid thermal contraction. Using a raft is a little bit more complex than using a brim, therefore it is recommended to first use the default settings of your 3D-Printing slicing software. If the default settings are not enough, it is always possible to change the settings to make them meet your requirements.
Pro’s and Con’s of rafts:
+ Easily and quickly removable from your bed and 3D-Print without remains
- More complex settings
- A lot more filament waste
Adhesion of your print bed
Finally, a good adhesive applied to your print bed is important during 3D-Printing. The easiest method for this is applying Kapton spray. When this spray is heated up with the heated bed, the Kapton material will become sticky and will adhere to the 3D-Print, holding it in place during 3D-Printing.
Make sure to let your 3D-Print and the heated bed, cool down before removing the product. The adhesive loses its effect when it cools down to room temperature so trying to remove it prematurely can cause damage to your 3D-Print. There have been incidents where glass printing beds actually shattered by premature removal of a 3D-Print which was still in the process of cooling down.
If you have any questions about warping or the prevention of it but could not find your answer on this page, feel free to contact our customer support service for more information and answers.