Personal Project
A while ago I got the idea of making my own 3D printer. After a lot of research I eventually embarked on my own build. Due to the severe lack of availability of parts during 2020, many of the structural parts were made from scrap wood I had around the house. While this makes it look very home made, the print quality is surprisingly good. Currently I am in the process of designing new 3D printed parts to replace the wooden ones, and each time I do, the print quality gets slightly better. This is in fact a concept developed first at the University of Bath which developed into the Rep-Rap project. The concept takes inspiration from nature whereby organisms are self replicating, and capable of improving their own design over time. Under the Rep-Rap project, printers are manufactured and then used to print new printers, so becoming self replicating.
The printer frame is based on extruded aluminium which is reasonably cheap, although I had intended to use scarp carbon fibre, I had no access to this at the time of building. The movement is enabled by 5 stepper motors, which move each axis along guide rails. Lubrication free polymer bearings keep the motion smooth and have the added bonus of being essentially maintenance free. Experience with the C-Scan ultrasound machine at work convinced me that greasy bearings and dust are not a pleasant combination for smooth linear motion! The brains of the printer is an Arduino mega micro-controller, paired with RAMPS 1.4 board that helps manage the electrical connections. Both boards are open source, and the RAMPS board was actually designed as part of the Rep-Rap project. The firmware controlling all of this is Marlin, another opensource community based project. This software takes information sent from a computer in the form of G-Code (long established for CNC control). Marlin interprets the G-Code and sends the appropriate signals to the required pins of the RAMPS board. While any computer can by used to send the G-Code to the Arduino, I use my Raspberry-pi. This is largely because it is very reliable, but it can also be permanently tethered to the printer as I have a few Pis.
As time goes on I will upgrade the wooden parts to improve precision and build an enclosure for it to minimise temperature variations during printing which causes warping. For now I am enjoying printing many useless, and sometime slightly useful parts for around the house! I have no doubt that this will become useful for my work, I have lost count of how many times I wanted a little jig but could not justify the expense of having one made!
