FDM 3D printing has gone beyond prototyping and has been used as a production tool by many companies. However, the conventional printer still needs an operation to eject the completed part of the bed and start a new printing. [Thomas Sandladerer] He wanted a way to replace the bed without manual intervention, so he built an automatic printing surface replacement system.
The most obvious solution to this problem may be a tape printer like Creality CR-30, but these have some trade-offs. Bed adhesion can be a problem, and the lack of a rigid printing surface can cause some parts to warp. [Thomas] It is hoped that PEI-coated steel beds can be used to avoid these problems. His solution is a system that pulls out the bed from the “magazine” and rolls out the old bed after the parts are completed. It still uses a magnetic heating bed, which is lowered before replacing the printing surface. Each printing surface is installed in a 3D printing frame that sits on the tool changer frame and holds it in place when the heating bed is lowered. The bed frame uses ASA printing and can handle 90 C without any problems. The pushing mechanism and the heating bed descending system are driven by a stepping motor connected to the output of a spare motor on the printer control board. The printer in question is Voron 2.4, which is very suitable for this application due to its high printing speed.
This tool change system is only the first prototype, but it still works well. [Thomas] Key improvements are planned, such as a larger print bed and reduced height. This system may be very suitable for small and large printing farms. We have already seen another bed cleaning system that does not require additional surface construction, but scrapes off the finished part.