Machine & Machanical Design | Week 12

  • Group Assignment Link.
  • Objectives of the Group Assignment:

    Mechanical Design

  • Design a machine that includes mechanism + actuation + automation + application
  • Build the mechanical parts and operate it manually
  • Document the group project and your individual contribution

  • Machine Design

  • Actuate and automate your machine
  • Document the group project and your individual contribution

  • Our Hero shots and videos:


  • We had a brainstorming session to decide on the machine, it's applications and what kind of mechanism should the machine have. We had different ideas; however, we thought of making a machine that can print circuits using materials like conductive clay or ink, etc.

  • The idea behind using a conductive clay or ink is to make a low-cost material, which is easily available. We thought of making the conductive clay using a play dough (made of common flour) that can be safely handled by the children. We went through the following video to know more about the conductive clay.

  • Source and Credit for the literature: TED Talk youtube channel.

  • Selection of a Mechanism:

  • Together as a group, we went through different mechanisms that can be best suited to design and build a printer. We concluded to use CoreXY mechanism in our printer. Click here for Reference and credits.

  • .

    Process Flow:

  • We assigned following tasks amongst ourselves building the machine.

  • Fenil and Kishore

  • took the responsibility to design the CoreXY mechanism and gantry of the machine.

  • Kiran

  • had the responsibility to design the extruder and prepare the conductive ink.

  • Jaydeep

  • took the responsibility of all the fabrication like laser cutting, 3D printing, conventional cutting and grinding.

  • Devesh and Vrushabh

  • had the responsibility of electronics part, which included electronics hardware, firmware and interfacing.

  • Ashish

  • was majorly contributing in to assembly process (entire machine including the extruder assembly) and preparing the conductive ink.

  • It was decided that after all the sub-assemblies and ink become ready, everyone will participate in the assembling and testing of the machine through test runs followed by the testing of the application (working on the circuit printed using the conductive ink).

  • Bill of Material:


  • We laser-cut the mainframe and middle frame plates. We also cut the L shape bracket and T-slot brackets using laser cutting.

  • RDworks:- Import design in Rdworks

  • Laser Cut Cutting Video

  • 3D Printing

  • We 3D printed the L shape bracket for mounting linear bearings for Y-axis and also T holders for guide rails after we found issues in assembly later. We have mentioned the issue later in the document below.

  • 3D Printer Printing Video

  • Cutting and Grinding

  • We needed to cut the guide rail shafts and one aluminum extrusion as per our design, we used power cutting and grinding tools for these operations, and we also provided a chamfer on the edges of guide rail shafts.

  • Assembly

  • Once all the parts were in place (either purchased, laser cut or from our lab inventory), we started to assemble the machine. Following is a picture of all the material in place.

  • Assembly Video

  • .

  • We started with building the base frame with the aluminium extrusions we had. We levelled them as we were assembling them. We started assembling the main frame sub-assembly and middle frame sub-assembly.

  • The T-slots we had cut on laser were not cut as per the designed specifications. So, they were not sitting in place. We fixed them using the glue just to check if the assembly works. This was not a permanent solution though.

  • We started assembling all the parts to the assembly, like stepper motors, pullies, timing belt, hardware, etc.

  • However, during the assembly process, we had fitment and alignment issues with T slot brackets that hold the guiderails along the Y axis, L shape bracket that hold the linear bearings. The T-slots cut by laser were not having proper press-fit and the L-shape bracket was not at perfect 90 degrees. Apart from that these guiderails had single linear bearing each, so the movement of the mechanism along the Y axis was not happening smoothly, it was wobbeling too much.

  • So we decided to go for 3D printing of T brackets for holding guiderails and L bracket for mounting linear bearings. Also we added an extra bearing each to the Y-axis guiderails as shown below.

  • This major hurdle in building our machine was thus removed successfully after implementing this solutions. The mechanism was working perfect now.

  • Actuation

  • After we replaced these parts and adding extra bearings, we re-assembled all the parts again and we were able successfully actuate the mechanism as shown in the video below. It works pefrectly fine on all 6 different movements.

  • Machine Output Video

    Safety Switch by Parejiya Jaydeep is licensed under CC BY-ND 4.0