After My graduation I decided to work as an intern at a startup (Subedge Technologies), where our team was involved in developing a low-cost delta 3D printer for schools in India. In, India the market for 3D printers is at its nascent stage; However it offers huge growth opportunities in the future. Our main goal was to make changes to the existing open source 3D delta printer designs, and manufacture them at an affordable cost for college students and schools, so that young kids will be exposed to the world of 3D printing and the vast opportunities it provides. The cheapest 3D printer currently available in India currently is an unassembled Prusa i3 RepRap 3D Printer which costs around RS 21,000. Design for assembly is a methodology used to improve the manufacturability of assembled products. It is a systematic analysis process which primarily intends to reduce the assembly time and cost of a product by simplifying the product design (Tatikonda, 1994). In order to achieve the objective of designing an efficient and easy to replicate stage of desktop 3D Delta Printer, DFA was introduced to reduce the time taken in the assembly process. The primary objective of DFA is to minimize the part counts. This leads to fewer parts that must be manufactured and assembled, which will be reflected in assembly time reduction for manufacturing process. Additionally, fewer parts and fewer interfaces also cause fewer failures, which has the potential to reduce the time taken in the testing and verification process of the product development. Another objective of DFA is to have remaining parts easily assembled together. Ease of assembly would contribute to the reduction in assembly time. Based on the conclusion in Tatikonda’s research (Tatikonda, 1994), the expected DFA results are reduced material cost, labor cost and reduced assembly cycle times. The total product development time is reduced greatly because it would be possible to reduce and eliminate multiple and time consuming loops in the manufacturing and testing processes. Keeping the above points in mind we developed our first prototype delta 3D printer at cost of Rs 13,000 including the cost of manufacturing, assembly and electronics. The printer we developed has a wood frame and 3D printed components and kept the design simplistic with minimal parts for assembly.
The First Prototype
Basic Frame – The steel rods offer vertical rigidity while also being the runners for the plates to which the print head arms are attached. To ensure the whole structure is rigid the rods are a tight fit top and bottom where we have doubled up on the thickness of the wood to help.
Runners along guide rails – The runners are 3D printed, encasing the standard linear bearings, providing a good square fit. The belts are secured onto the runner by providing a through slit.
Return pulley belt and idler system.
The nemma 17 motors are mounted at the Bottom. The motors are held in place by custom 3D printed Brackets.
PLA/ABS Feeder, mounted onto to the frame using 3D printed bracket.
Extruder Mount and Aluminium arm rods with ball joints.
The printer workspace is
24 x 24 x 25 cm,
Printing speed of 300 mm/sec
The printer uses the standard electronics for 3D printing. Arduino Mega and Ramps 1.4V Board.
3D printer in action.