Design

In this week assignment we have to solder our own FabISP. We are using pre-designed files and following the FabISP guide on the FabAcademy Archive. This version is Brian's FabISP model, using a ATtiny45 chip.

Comments

This assigment was difficult for me because I don´t have much electronics background. Took me some time to understand why we were using Brian's model and no other. Also some people decided to modify their model making hard to me deciding. Some hours later took my decision and start to mill the PCB folliwing Brian's model guide.

PCB milling

Milling

Beacuse we already have the milling traces, al we have to learn was to use the machine. In our FabLab we have a Modela mill connected to a Ubuntu PC. Learned how to load and send the trace file to the modela. Also learnead how to set the machine to start milling.

Cutting

I could only have the traces milled but could not cut the shape with the mill, that why had to cut it with a tool. I was taught that have to heat the board before cut it, because it could break and damage the traces. After some hot air, I had my board ready to soldering

Comments

A simple task sending files, using known parameters, there is no problems any person can work with the software but it is important to try several times how to set the machine origin ir order to avoid any tool break.

The hardest part of this assignment for me was cutting the board. I had to mill 3 times before having my final board, first because breaked the board with the cutting tool, and second due bad board fixation. And when finally had my final board, almost break it again. Think I would have to train harder with the cutting tool.

Soldering

First thing: Soldering training. I had to no experience with soldering electronics so stated to solder some broken componentes to one of my discarded boards. After some training , started with my final board. Brian's guide detailed every component I had to use, so I could find everything for my self. Finally after an hour I had my board ready

Comments

I took a couple of hours to find the appropriate soldering technique. It is something you need to try for your self and can't be read in a book.

Testing

Connected my FabISP to a AVR ISP and it recognized (two green lights).

Comments

It took a while to the ISP to recognize it. I have to add some ducktape to the board in order to make it close-fit. After some tries I saw the light!