Week 4_ ELECTRONICS PRODUCION

For the group project we used the milling machine with two different direction settings: climb and conventional.
The milling cutter in our lab is a Roland MDX-40A cnc router.

Roland MDX-40A of the lab

PCB fabrication

In order to design the PCB there have been several preparation moments.
I choose a Fab Tiny board to make this assignment. Step by step:

  1. I did the schematics by Eagle.

    2. Eagle schematic

  2. I did a PNG with the drawing of the circuits.

    3. Printable drawing

  3. I exported it by FabModules.

Mods

Milling machine XYZ origin setting

I prepared the machine and regulated the level of the cutting element on the copper surface using this DIY tool: when the LED lights on means the level is right to set the Z origin of the milling machine.

Electrical surface test tool

Electrical surface succesful test feedback

PCB milling

After turning it on, I moved with the head machine of the machine with its software over the area I desired to start milling, but before pursuing in this operation I had to zero the coordinates and adjust the height of the mill.
  1. I milled the PCB with the Roland MDX-40A. I prepared the milling machine taping carefully the PCB board and chacking it was well standing on the milling surface.
    I turned the machine on, I zeroed the coordinates adjusting the height of the mill, and moved the head of the machine using the arrows on the Roland where I wanted the milling to start.
    The two types of manual movement setting on the softwere we use in the lab: continous, for rapid movement across the board and by staps 10/100/1000. The last option is the best for controlled mill positioning.
    After these steps, set Z command and initiate the milling process using a 1/64 tip.

    2. PCB milling

  2. At the end of this operation, I removed the copper dust on the board surface with a brush.
    Then I changed the tip to a 1/32 to drill the holes and cut the outline.

    3. PCB milling finished

  3. I unsticked the piece from the cutting surface and then I cleaned it.

    4. PCB milled piece

FabTinyISP components addition

  1. I sticked the clean PCB to start soldering the components of the bill of components.

    2. PCB bill of materials

  2. I started soldering for the first time.

    3. PCB soldering

  3. I added the components to the PCB.
    My first try failed, since i positioned the AtTiny in a wrong angulation.
    The second time I corrected it and it came out better.

    4. PCB with wrongly positioned AtTiny

    Final solded PCB

Ribbon ISP fabrication

  1. The ribbon is a bridge that connects the boards to a programmer or to other boards.
    First of all, you have to take only 6 strings and close them with a pincer.

    2. Insert the ribbon

    Press the component

    Ribbon