Electronics Production | Week 05

Week Content

Tools Used
  1. Roland MDX 20

Milling PCB ( LINUX )

  • PNG image is required for milling
  • We have Linux laptop connected with Milling Machine
  • Open Terminal > sudo fab
  • After Opening you have to select type of image which is PNG and select Machine which is to be used
  • Then Load PNG to software and make a path ( You can change offset settings)
  • After Making Path you have to adjust machine according to start point which can be done from X and Y axis distance setting
  • After you done with start point you can Create RML and load it to Machine


    • Milling Bed level is very important fro Circuit Production, It should be clean and level regularly.

Soldering SMD Components



Components required for the FabISP board

  • ATTiny 44 microcontroller- Qty:01
  • Capacitor 1uF - Qty:01
  • Capacitor 10 pF - Qty:02
  • Resistor 100 ohm - Qty:02
  • Resistor 499 ohm - Qty:01
  • Resistor 1K ohm - Qty:01
  • Resistor 10K - Qty:01
  • 6 pin male header - Qty:01
  • USB connector - Qty:01
  • 20MHz Cystal - Qty:01
  • Zener Diode 3.3 V - Qty:02

Programing ISP (MAC)

Installation for MAC As Home Brew is already installed
we have to install Crosspack ( It will require to over ride your Mac Firewall as it is not from Verified developer)
I need to install AVR GCC as mine wa not working.
I have shared Screen shot of the process.
  • https://www.obdev.at/products/crosspack/download.html
  • Follow the link. http://archive.fabacademy.org/archives/2017/doc/programming_FabISP.html#mac
  • Downloading Firmware and then unzip to a Folder.
  • Connect Your ISP to AVR loader and Laptop
  • Go to folder in Terminal.
  • now you need to enter commands in terminal and check the folder.
  • make clean ( This will delete some files in folder)
  • make hex (This will create some file ) (I got AVR GCC not found over here which was solved after adding AVR via terminal)
  • make fuse
  • lsusb
  • Go to apple icon > About this Mac> System Profiler > Hardware > USB > Hub
  • FABISP is listed in USB then it successfully Done
Using FAB ISP PNG file in milling








Line Test to check cha

Through the group assignment, we will go through the process of fabricating a Traces-width board, assessing how separated can our traces be, as well as how thin they could potentially be. The board we will be machining is found below, and we will be using copper PCBs machined in either Modela MDX-20.
The traces png file to be machined with a 1/64” tool:
To cut the board out of the copper layer, we will use a 1/32” tool on the following profile:
Both png files will be passed through the FabModules. Note that this tool will detect changes between BLACK and WHITE in the png files and generate a path in it for the machining process.

The settings selected for the PCB traces are:
  • Upload image as *.png
  • Output file as Roland mill (*.rml)
  • PCB traces (1/64)
  • Machine: MDX-20
  • Origin: X10, Y10 and Z-0.01 are set ,you can set as per your placement of pcb
  • ZJog is set to 2mm, meaning that the machine will lift the tool 2mm while not cutting
    • Xhome, Yhome, Zhome are set to 0mm, 0mm and 5mm. The latter being the most important, since it is the value at which the tool will be positioned once the job is finished. If this value it’s zero, it will scratch the whole
  • copper surface, very likely breaking the tool
  • Cut depth: 0.19mm
  • Offset: -1. It’s the number of offsets that the program will calculate out of the BLACK-WHITE transitions. A number of -1 will remove all the copper.
  • Offset-overlap: 50%, relative to the tools diameter (1/64” in this case)
  • The settings selected for the PCB outline (only detailing the ones that are different):
  • Cut Depth: 0.4m
  • Stock thickness: 1.5mm
  • Number of offsets: 1

Somehow the fab modules was not able to detect the lines beyond a certain dimension. The changes were very minimal. We tried changing different parameters in the setting and yet the result was the same. The .001 trace was too thick than its natural size.
Milled Board
Changing the tool diameter from 0.4 to 0.1 resulted in trace becoming thin, but we were unable to get the desired result using default settings in fabmodules.org. We were unable to figure out what the mistake was.
Testing with tool diameter 0.1mm

From the above test it's understood that the minimum width the bit can clear is 0.016"(0.4mm) which is the diameter of the bit. The minimum trace is inconclusive as we had some difficulties in generating the right .rml file from FabModules.

Group Work

http://archive.fabacademy.org/2018/labs/fablabcept/electronic-production-week-05.html

We have all togather worked on Milling Machine to understand it process and specification. Aadithya helped us to mill this board and check its output with various parameter.

Some Quick Points

  • Keep Laptop connected to Power if that stopped milling would stopped and u need to do it again.
  • Take screen shot or note origin it will help you if system is reset or tab get closed
  • Bed leveling should be done after doing level of table bcoz i did a mistake of leveling with reference to table which was unleveled.
  • Always run a path above the level in air to check after you are become sure you may initiate milling.
  • for milling satsha or 328p based boards use speed as :1 that will help get more finished surface without broken lines.

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