How To Make Almost Anything

Project 02

Electronics Production

Given that I knew I would be out of town for most of this week on a field assignment, I wanted to get started right away with electronics production, something I have never done before. After the walkthrough on how to use the Modelo, I found the process to be relatively straightforward, as long as I followed the step by step instructions, which I have listed below. Even the sautering turned out much easier than I thought, as I first practiced many times on scrap PCB boards before working on my final. Though I have yet to finish troubleshooting my board, this is a good first step in designing my own electronics.

  • Design Challenge: Make an in-circuit programmer
  • Software: N/A
  • Machinery: Modelo, Sautering Iron
  • Date Completed: 09.28.16

Machining and Sautering the PCB

I began by following the instructions on Rob's website, and loaded the image of the board I wanted to fabricate

Adjusting Machine
Adjusting the 1/64 endmill
  • Hold down copper board with double stick tape.
  • Underlay is under the board to avoid cutting the bed of the mill (sacrificial layer).
  • Loosen the set screw, but hold onto it! No dropping when setting the orientation
  • No need to tighten set screw as tight as you can.
  • Remove burrs with a straight edge.
  • Wash the board.
Finished Cut
Cleaned up board after machining

Once I had a complete board, I cleaned it off with sandpaper and began setting up the tools I needed to sauter. I used Rob's suggestion to write down all the components needed on an index card. Then, I placed a piece of double stick tape down, and taped on any components I needed, so I didn't have to worry about losing tiny pieces as I sautered. This greatly improved my workflow as I had enough to think about when sautering!

Paper Set up
Setting up my workspace to begin soldering

I have never sautered before, so I was definitely surprised at how quickly the process goes once you get into a groove. The only real trouble I had was with the tiny legs of the USB port and the microchip. I sautered a huge glob of sauter and learned to use the braid to remove excess sauter. Since I didn't get the timing right at first, I kept sautering the braid to the board, so that took a few tries before I got the rhythm down.

Finished board
Finished PCB with all components sautered on

If I had more time, I would improve the shape of the X so that student work could be tacked onto each piece easily, or I would build the entire divider out of sturdier material so that it can last multiple uses.

  • Clean tip of sautering iron.
  • Underlay is under the board to avoid cutting the bed of the mill (sacrificial layer).
  • Cover sauter tip with a bit of sauter (SHOULD BE SMOOTH AND SHINY).
  • Heat BOTH lead and copper where they join.
  • Put down a little blob of sauter and then wait for lead and trace to heat up.
  • Gently probe at sauter, when it starts to flow up.
  • Wait one second for it to flow.
  • If gnarly, try it again, and use new sauter to make old sauter flow.
  • To stuff, start from the middle of the board to the outside of the board.
  • Then, start with low parts to high parts.
  • For small parts, put a little sauter to just take down one side.
  • Then, using the tweezers, hold the electronic component in place.
  • Melt the sauter to hold it in place.
  • Sauter other joints properly.
  • Finally return and resauter the first joint.
  • Check all joints under a microscope to be sure it was done correctly.

There was nothing wrong with the voltage and the board and the microchip did not grow hot, but I need to do much more testing this week to figure out exactly why it didn't load the program.

Testing the voltage at each connection