Group assignment

The group assignment is here.

Key learnings (from group and individual assignment)

• The V-bit end mill is very robust, but the width depends on how deep it goes. There are formulas to calculate the width, but we have to validate them in practice, and we used predetermined values for the width for the end mill we used.
• There are limits to what clearance we can get with this milling process, and commercial providers are able to get smaller clearances (and more professional results).
• Although the PCB stock plates look straight to the eye, in reality there are small differences in height either in itself or on the method that attaches it to the milling machine bed, that need to be accounted for with Z probing to get a height map. If they are visibly bent, one can try to manually straighten them before doing the surface mapping.
• There are tools (like EasyTrace5000, or mods CE) that convert a board image into tool paths that can be used for milling on a CNC machine.
• Having more clearance, when possible, will facilitate soldering later, and have less chance of accidentally short-circuit something.
• Using a multimeter to confirm conductivity and isolation on the board and solder points.
• Using a steel wood abrasive pad (like scotch brite) to deburr the PCB finished board to prevent stray copper hairs from causing short circuits later.
• Checking the polarity of a SMD LED with the multimeter
• How proper heat transfer is essential for a successful soldering process