11. Mechanical & Machine Design¶
Task to be carried out this week¶
Group Assignment¶
- Design a machine that includes mechanism+actuation+automation+application
- Document the group project and your individual contribution
- Build the mechanical parts and operate it manually link to group assignment
The softwares used during the week’s assignment¶
- Autodesk Fusion 360: Making designs
- Aspire: Controlling the Shopbot
- DXF to G-code converter: Controlling the machine
- Visual Studio: For Documentation
Idea Conception and Planning¶
The idea came from the problem when milling our PCB on the current PCB milling machine. The bed level on the current Roland- SRM20 machien that we are using had become uneven. DIe to this we faced a number of problem when milling our PCB for output week. This also caused for the loss of a number of copper plate. Thus, we thought why not try to create a PCB milling machine for this week’s machine making week. Once we all agreed on the idea, the next step was to explore on how to build the machine. Since we do not readily get the electronic components in our country, we had to ensure that all the electronics we required were available in the lab. For this we had to dismantle a couple of previously made machines. We gathered all the electronics we required and then started with the work. Our group had 7 members, thus we divided the tasks for efficiency. Two people were allocated for designing the components, 3 for electronics and 2 for documenting the entire process. For the assembly and testing the machine, we all worked together.
Our plan was to make the machine similar to the one shown in the picture above.
Design and printing the parts¶
Initially we planned to 3-D print majority of the components but we realsized that the 3-D printer available at out lab was quite small and had the capicity to print only models with maximum of 180mm dimensions. Hence, we cut the bed for the milling machine on the CNC and the body frames using circular saw. For the machine body, we used Alumnium frames and polymer slabs which were cut using circular saw. For the bed, we used wood and cut it using CNC. However, for smaller components such as the cable holders and rod holder we 3D printed them.
Machine Base and body parts
Electronics¶
For the machine controller, we used Arduino Mega as the microcontroller. Arduino Mega Motor Shield was used to connect the motor driver to the microcontroller. We used 3 moter drivers to control the X,Y and Z axis.
Machine Assembly¶
Machine Control¶
For controlling the machine we used G-Code. We downloaded an software called dxf2gcode which converts 2D dxf drawings to CNC machine compatible G-Code.
You can download the software from here
Testing¶
Once the machine was assembled, we tested the machine. There were 3 major testing we carried out;
- XY-axis test
- Z-axis test
- Bed allignment test We tested the XY-axis, once the bed was assemnled. We found that the supporting rods were not alligned with the slot bearings, thus we used filers to recitfy that. Next, we tested the Z-axis and bed-allignment and made the necessary changes to recify those issues.
Final Working¶
My contribution¶
Throughout the whole process me with my course mate Sonam Deki were given the task of documenting the progress and to make the final video. So all the documentation process were done by the two of us collectively and did the video editing and compression too. We used canva an online platform where we can edit images, videos and lots more. It’s very user friendly and is a free online software for photo and video editing. For most of my assignments documentation I used canva. To compress the video since the size must be less than 10 mb, we used an online video compressor Free convert.
Final video link of Group A¶
PCB milling machine video link
Files¶
Holder stl file
G-code with inkscape
G-code with G-code converter
MARLIN firmware download link
GRBL firmware download link