Building and Soldering
We weren’t quite sure how to begin; there was no instruction manual. Nothing in the box indicated a starting point. We decided to pull up the wiki and see if that would help. I remembered that we needed items from our “shopping list”, which included: a soldering iron, some soldering material, wood glue, and tape. Kevin mentioned that he had a soldering iron and some material in his office, which he retrieved. I asked the main office for some tape. When I returned we scanned through the wiki for a starting point. To get to the guide on the wiki we clicked on the ‘CupCake CNC’ link at the top of the left-vertical navigation bar. The “Before You Build” link is on that page and houses the list for our “shopping list.” There were some sequential material regarding the materials, but everyone was so excited to start the building that we jumped ahead to the electronics assembly.
Alex and Kevin led us in building the assembly. There were six boards we needed to build and there were six groupmates so we all grabbed a board and with Alex’s guidance we were able distinguish the names of the pieces and how they fit onto the board. We followed the link shown on the wiki and piece-by-piece each built the assembly. Some of the questions that arose were:
- “Is there a wrong direction to putting in the resistor?”
No the resistor could be placed in any direction as long as each is placed in the correct holes.
- “How do we know which resistor goes where?”
The wiki shows us the correct order. The resistors are distinguishable by colored stripes.
- “Which end of the LED goes in where?”
This was the most difficult issue we dealt with (besides where to start and how to choose a leader). As we scrolled down, there was a step on the LED. The instruction mentioned something about the short wire of the LED being adjacent to the flat portion of the silkscreen. We did not know what that meant. Alex looked at the board and noticed that the white print on the board has a flat portion where the LED is to be placed.
Soldering could now begin. Kevin checked on the soldering iron that plugged in before we started but returning to it he realized that it did not get hot. The plug was in, so Kevin jiggled the plug and for some reason it started getting hot. As Kevin worked on the soldering iron, Alex noticed that we just set up 2 extra assemblies. We only needed 4 of the assemblies and needed (2) 3 pinned assemblies. After having some trouble taking the 2 extra assemblies apart, I helped Alex with that board since I had nails.
Kevin was able to show us how to solder the pieces to the board. This is done when the soldering iron is hot. Kevin and Alex assured us that if a mistake is made while soldering fixing the solder would require merely taking the bad solder off and redoing the solder. The metal parts of the pieces that stuck out from the board were bent to avoid falling out of the board when soldering. Placing the board upside down; metal pieces sticking up, Kevin used the wire (which we were told is made of led and instructed to wash our hands afterward) by touching it against the metal and melting the wire onto the metal piece creating a metal bond. Kevin also instructed us to breathe out as we are soldering to avoid breathing in the fumes and to cool the melted bond. Alexis was able to try her hand at soldering and received praise by Kevin for her clean soldering.
Unfortunately, due to time constraints the remainder of the group was not able to solder.