8. Electronics production

Files

Here

Group Site

Group Link

I characterized the bits that we used this week.

Overview

This week’s goal was to create my very own MicroController PCB and test it. I used the Seeed Studio Esp32-S3 Xiao MicroController to control a button using a button, LED, and two resistors of different ohms.

Milling

Pre-Process

I decided to use the Kicad design from my week 6 electronics Design as the model for my milling this week. We were also given 4 of our bits. These include a: PCB engraving bit 0.005, 1/16, 1/32, and a 1/64.

Milling Process

A. Step one was to upload my F.Cu file and my edge cuts file to the Fab Lab drive so I could open them on Bantam tools.

B. Next I needed to take a piece of metal copper thingi and tape it using double sided tape into the milling machine

C. I had to define the size of the material in Material Setup which were 102.8 by 83.5 by 1.64mm, then define the z offset to be 0.2mm.

D. I grabbed both my edge cuts file and my F.Cu files and imported them into the Bantam Tools software in File Setup where I can control the Milling Machine.

E. I chose the tool for both files to be the 1/32 bit and defined the F.Cu to be holes and traces (even though I had no holes) and defined the EdgeCuts to just be outline. Then generated the gcodes for both.

F. Finally for plan setup I needed to change the positions of both of the files to be able to fit them together in an open spot on the piece of copper.

G. I then clicked Mill All files where it then prompted me to change the tool to the 1/32 bit. I did this by using 2 different wrenches to hold the spinning shaft still and another to loosen the nut holding the tool already inserted. Then I inserted the 1/32 bit all the way through the opening and then tightened it in.

H. The machine would then touch off the tool and begin milling. I would need to watch it to ensure that no errors could occur that would cause problems.

I. Finally after it finished milling I would use the vacuum to try and clean all the dust left by the machine. I peeled off my PCB and viola I was done.

PCB Soldering

Soldering Workflow

This process outlines the full steps for soldering electronic components.

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Materials & Tools

Tool / Material	Job
Soldering Iron	Heats solder for joints
Solder	Connection metal
Wire Stripper	Removes plastic insulation
Helping Hands Stand	Holds components while working
Solder sucker	Removes excess solder
Flux (optional)	Improves solder flow and cleans Soldering Iron
Safety Glasses	Protection from fumes

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Step-by-Step Process

1. Set up workspace with ventilation (fans are best)
2. Heat soldering iron and clean the tip with flux
3. Secure components using helping hands
4. Apply flux (if needed) to components
5. Heat necessary area (not solder directly)
6. Stick solder to heated joint
7. Inspect joint (shiny = good, dull = bad)
8. Cut any leads and clean the area up

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Solder Joint Quality

I had some problems with cold solder (Non conductive connection of solder) so here are my important examples of a good soldering job.

Good Soldering Job:
- Shiny surface
- Cone-like
- Strong electrical conduciveness

Bad Soldering Job:
- Dull or grainy
- Blob-ish shape
- Weak connection or cold connection

Final Poduct

Programming

The code I used to program the S3 is seen below it uses the same code from week 6.

int buttonState = 0;

void setup()
{
  pinMode(D6, INPUT);
  pinMode(D2, OUTPUT);
}

void loop()
{
  // read the state of the pushbutton value
  buttonState = digitalRead(D6);
  // check if pushbutton is pressed.  if it is, the
  // buttonState is HIGH
  if (buttonState == HIGH) {
    // turn LED on
    digitalWrite(D2, HIGH);
  } else {
    // turn LED off
    digitalWrite(D2, LOW);
  }
  delay(10); }

Testing

It works but it can be a little weird here and there.

Reflection

This week I learned and worked with the OtherMill small PCB milling machine to create and test my very own PCB. Using the files I created in KiCad and tested in Wokwi. I learned how to insert the material correctly, change the currect tool bit in the machine, and clean up properly after milling. In my group project I learned how to charecterize the bits used in milling my own PCB. I also learned these soldering tips:

• Prepare the workspace safely
• Tin the iron tip correctly
• Use helping hands to stabilize components
• Apply solder with precision
• Inspect and rework cold joints
• Use desoldering wick for mistakes

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Last update: November 27, 2025