Thermwood AM machine
A Thermwood LSAM machine
High-performance CNC Routers provider, Thermwood has updated its Large Scale Additive Manufacturing (LSAM) systems by adding thermographic imaging as a standard feature.
The feature has been added to make it easier to adjust and control the printing process. Thermwood hope this will result in the best possible printed structures for their clients.
In order to print high quality, void-free large-scale 3D printed structures, the previous layer must be cool enough to support the new layer without distorting, but must also be warm enough to fuse with the new layer as it is applied. For this to be accomplished, the temperature of the print surface throughout the printing process must be known and then controlled. The goal is to continuously operate within the narrow range of temperatures by which each material for 3D printing is optimal.
Thermwood’s new thermographic imaging system shows the operator a full colour thermal image of the part as it is being printed. When the part is within the ideal temperature range it is met with a green light. The thermal image is displayed on the control screen in a movable, resizable window.
With print temperatures known and the ideal level identified, Thermwood’s print head control makes it easy to adjust printing parameters to achieve the ideal print surface temperature. For instances when the part becomes too hot, a fan cooling system can be implemented or the print speed can be reduced, allowing for more time to cool between layers. Similarly, if the part temperature becomes too cool, print speed can be increased or cooling reduced.
Thermwood’s high output print heads are also important to quality printing of large parts. Previously, trying to print large parts with low output print heads meant slow print speeds. This prevented the print head from returning to a point before it became too cool to achieve a proper layer to layer bond. The high output print heads prevent this from happening and allow for quality large thermoplastic composite parts to be made. Meanwhile, the new thermographic imaging system provides temperature guidance which helps the operator to consistently achieve optimum results.
The thermographic camera can be mounted in three different locations. One, is a fixed position on a stand, inside the machine, facing the part. Another is on the print gantry – this works well for parts that are too large to view as a single image. The third location is the print head itself, for special applications. Image output from the camera is integrated with Thornwood’s print gantry CNC control and the full colour temperature image is displayed on a resizable window on the control display itself. A touch screen then allows the operator to select any point on the image and read the exact temperature of that point.