Machine Building Group Site¶
Project name: Metal Man¶
Slide and Video¶
Documentation¶
Disassembling the Lathe¶
We began by disassembling the machine and cleaning all the parts. It hadn’t been used in a long time and was covered with dust and grease.
Cleaning Parts.
Designing the Parts¶
We initially considered modeling the machine from scratch, but luckily found a complete 3D model on grabcad.com.
We opened the file in Fusion and compared it to the real machine to verify the accuracy.
The model matched well, so we imported it and began making necessary changes.
We designed an adapter to mount two stepper motors.
To reduce friction, we added a bearing housing, which we later milled.
Part to be milled with the CNC machine:
Fully assembled result:
Prototyping the Mount¶
Before machining in aluminum, we 3D printed a prototype.
It fit perfectly on the machine.
G-code Generation¶
We generated G-code in Fusion 360, using the 2D Bore toolpath under the Milling section to enlarge circular holes with precision. This allowed us to define parameters like diameter, depth, and feed rate.
Detailed steps can be found here.
Running a simulation helped us verify the toolpath and catch potential issues early.
Milling Process¶
We used this beautiful CNC machine to mill the aluminum part:
After securing the material, we ensured the spindle wouldn’t hit the clamps.
We set the zero point using a dial indicator to align with the center of a hole. Although the hole wasn’t perfectly round, we minimized deviation enough to proceed.
The Z-axis zero was set at the surface. With everything in place, we loaded the G-code and began milling.
Metal milling requires continuous lubrication and cooling. Sprayers near the cutter help with this.
Here’s the improved result after installing the bearings and aligning the gears.
Adapter for Stepper Motors¶
We chose 25 mm thick aluminum alloy for the adapter, as it’s strong and easy to machine.
-
2D Adaptive — for fast roughing.
-
Drill — for creating mounting holes. Bore — for reaming pre-drilled holes.
-
2D Contour — for finishing edges and contours.
Simulation helped us visualize the full process:
To avoid issues, we left 1 mm of material on the backside during the first pass. After flipping and re-clamping the part, we removed the rest.
This video shows the milling process of the adapter:
Electronics¶
We repurposed an old CNC control box.
It includes safety switches, a current limiter, and an LED power indicator.
Inside: power supply, 2 stepper drivers, Arduino UNO with CNC shield.
We tested one driver separately.
Here’s the test setup with a power supply, waveform generator, and oscilloscope.
We experimented with different motor speeds:
Later, we cleaned up and organized the control box:
Software¶
To send G-code, we installed GRBL on the Arduino.
We imported the GRBL zip into the Arduino IDE.
Since we only use X and Y axes, we modified config.h to disable Z.
We used Universal Gcode Sender (UGS) to communicate with the Arduino.
We used the Setup Wizard in UGS to calibrate direction, steps/mm, and homing.
Connected via COM8 at 115200 baud rate.
We fine-tuned the steps per mm until the movement was accurate.
Protective Box¶
To improve safety, we designed a protective enclosure and vacuum attachment.
It was modeled in Rhino and we used 5 mm acrylic for strength and transparency. The enclosure fits the machine perfectly and is secured with screws.
The vacuum attachment was designed for our Total vacuum cleaner and 3D printed in PLA for quick prototyping.
Assembling and Testing¶
We finished assembling the protective box
And here is our beautiful machine:
We first tested with a wooden cylinder
Launching the job:
And here is our test result:
For our last test, we used aluminium. And it worked beautifully:
