Week 4 - Electronics Production Evan, Alana, Ryan¶
This week we were tasked as a group to characterize feeds, speeds, plunge rate, depth of cut (traces and outline) and also to characterize the design rules for in-house PCB production process.
Characterizing Milling Bits – Alana and Ryan¶
1/64” Flat End Mill Feed Rate: 688 mm/min Spindle Speed: 27500 rpm Plunge Rate: 381 mm/min Stepover: 50% Pass Depth: 0.4 mm Ramp Angle: 1 degree
1/32” Flat End Mill Feed Rate: 1100 mm/min Spindle Speed: 27500 rpm Plunge Rate: 381 mm/min Stepover: 50% Pass Depth: 0.8 mm Ramp Angle: 1 degree
1/16” Flat End Mill Feed Rate: 1650 mm/min Spindle Speed: 27500 rpm Plunge Rate: 381 mm/min Stepover: 50% Pass Depth: 1 mm Ramp Angle: 1 degree
Trace Depth: 0.15 mm Trace Clearance > or = 1.5 mm
Board House – Evan¶
For our board house, we used JLCPCB
- Create your pcb design in a software of your choice, for our design, it was made it Fusion360
- Export your file as the file type that the board house uses (usually it’s .gbr files)
- Test you gerber file in house to make sure that your file has no issues
- Upload your gerber file
- Define things such as your quantity and material along with others that you see fit in the customization options
- Place your order
Trace Testing PCB Boards - Ryan, Evan, and Alana¶
To mill our test PCB boards, we followed the same workflow as when we milled our boards for the individual assignment this week. In the end, we chose two different bits to mill the test boards with: we first did it with a 1/16 inch bit, and, shortly after, we milled the same design with a 1/64 inch bit.
The first board, milled with a 1/16 inch bit, failed completely (just like me). During the cutting process, however, we couldn’t actually tell how good the board was being milled because of all the copper flakes blocking our views. The picture below shows what the finished board looked like.
As you can see, the 1/16 bit left this board with no detail, only leaving behind faint lines and milling much more than it should have. In contrast, the 1/64 bit milled much more detailed traces, with legible numbered labels and thin but intact traces. To mill this board, we again used the same process as before, with the only difference being the fact that we had to load a 1/64 inch bit. The picture below shows what this board looked like after being milled.
