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Group Assignment

We started off the week by working on our second group assignment of the year, which can be found here

The Design Rules

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PCB Workflow

You can find more information on our group assignment page for this week, however, here is some basic information regarding the PCB workflow at our Fab Lab.

Our milling machine is the Monofab SRM-20 Milling Machine.

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Here’s a labelled picture that gives you a basic idea of how the machine works. I got this picture from my friend Damzang.

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End mills: Metal pieces that are used to remove material.

Sacrificial Layer: A layer below the copper plate that is slowly removed when the end mills go beyond the designated cutting area.

Zeroing Adjusting your end mill to be positioned at t=your set origin.


Here’s some extra information on the machine, such as the UI and how to turn the machine on.

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Reflow Soldering

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According to Wikipedia, Reflow soldering is a process in which a solder paste is used to temporarily attach one or thousands of tiny electrical components to their contact pads, after which the entire assembly is subjected to controlled heat. The solder paste reflows in a molten state, creating permanent solder joints.

In the time that we were at the Jigme Namgyal Wangchuck Super Fab Lab for a Makerthon event, Mrs Tshering Wangzom introduced us to reflow soldering. She explained and demonstrated how the process worked, and then we soldered a programmer using the reflow soldering process.

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The Pros and Cons

Reflow soldering seems like a really fun idea, and I was really excited to try it out. Reflow soldering allows you to solder components on with much more efficiency and accuracy, but the equipment is quite expensive, and the process only works for surface-mount components.


The resources that we used:

  1. XJS Solder Paste
  2. XG-Z40 10CC MECHANIC Solder Flux Soldering Paste with Free Needle
  3. The YIHUA 959D-II


Last update: May 20, 2024