Designing a comfortable armchair for JEC 2022
At CEAD, we wanted to design and print an armchair to provide visitors of CEADs booth at JEC World 2022 with the possibility to have a seat and watch live demonstration sessions with the AM Flexbot.
An important requirement for the chair was that it had to be comfortable to sit in. For the chair to be comfortable, we designed the seating surface to be double curved. Double curved surfaces are challenging to print because it requires a 3D printing strategy with overhangs. Each successive layer needs enough contact with the layer before to successfully adhere. If the successive layer protrudes too much, gravity will pull the plastic downwards causing drooping of the material. Printing strategies to realize complex shapes with overhangs, may include using supports or printing the part in separate pieces. These printing strategies require extra manual labour after the part has been printed, by having to remove the supports or having to put the separate pieces together.
Printing strategy on the AM Flexbot for complex shapes
To prevent this, we used our AM Flexbot and implemented a 40° printing strategy, a variant to the 45° printing strategy. The AM Flexbot is a 6-axis robot, whose extruder can be orientated anywhere between 90° and 0° relative to the print bed. This is one of the main advantages of robot-based 3D printing and provides more flexibility and design freedom. This printing strategy allows you to print parts containing horizontal planes or slopes without using supports. It also enables you to print the part in one go, thus not having to print the part in separate pieces. An example can be seen in the armrests and the seat.