GigaPrinter MAker Grant
The purpose of building the GigaPrinter was to further my knowledge of the operations of 3D printers, further my experience of machine design, and to design a 3D printer that is made from more COTS parts that allows for easy and frequent modification of the printer to meet many different requirements for print jobs. None of this, of course, could have ben done without the support of the Georgia Tech Flowers Invention Studio, who funded the purchase of COTS components for the GigaPrinter.
Fabrication of Parts
Most of the parts for the GigaPrinter were printed on an ender 3 pro. However, a few parts of the printer were either not producible on a 3D printer or would be subjected to temperatures greater than what PLA is capable of handling. These parts were printed by my teammate on this project who was in Atlanta during the build process. He was able to manufacture a hotend holder out of FormLabs High Temp V2 resin, as well as a 235x 440mm glass buildplate, cut from a larger buildplate of an old Fusion 3 printer using an OMAX waterjet. These parts were all produced in the Flowers Invention Studio
As COTS parts arrived, I began assembling the main structure of the printer as well as some of the dynamic subassemblies. Everything for the initial build went according to plan up until I had to make some modifications to a couple of designs.
Errors and Redesigns
As I built and tested components of my printer, I discovered a few oversights and designs flaws.
Power: As the GigaPrinter's buildplate is twice the size of an ender 3, the GigaPrinter employs 2 ender 3 heated beds to heat the entire buildplate. In an ender 3, the heated bed accounts for about 75% of the power drawn from the 360 watt power supply. As I was adding a second, the power requirements of my printer exceeded that of the standard 360 watt power supply I originally planned to use. Inexpensive and high quality 600 watt power supplies were difficult to find, so I instead used 360 watt and 240 watt power supplies, and used 2 external mosfets to power each of the heated beds, and built a control feedback loop to use the motherboard to control how much power each mosfet will allocate to the heated bed, governed by a thermometer on one of the heated beds. This of course assumes that both plates always hold the same temperature, but through some testing I determined their temperatures to within an acceptable tolerance.
Right Angle Extrusion Brackets/ Lead Screw Holder: While my original design for a piece that would both constrain two pieces of extrusion and house a bearing that supports a lead screw technically worked, I discovered that the part flexed more than I anticipated, resulting in the part breaking. Thus, I redesigned the part to have fewer thin breakable points, and be generally stronger than its predecessor.