Electronics Production¶

Group assignment requirements¶

The group assignment for this week is the following:
- Characterize the design rules for your in-house PCB production process: document feeds, speeds, plunge rate, depth of cut (traces and outline) and tooling.
- Document the workflow for sending a PCB to a board house.
- Document your work to the group work page and reflect on your individual page what you learned

Fine milling machine specs¶

A picture of your fine milling machine

Describe/list the available features and key settings of your laser cutter.

Machine name: Roland SRM20
Spindle Max speed in RPM: 8000 Machine bed size (work area): 232.2mm(X) - 156.6mm(Y)
Toolpath generation software used: FlatCAM

Safety¶

[Describe the safety measures around using your fine milling machine.]

Roland MonoFab is a small compact milling machine it needs some consideration while operating but the machine offers some saftey features; {the machine stops working when the door is open.}

PCB production process¶

For the Toolpath generation I will be using Flat cam which will allow me to generate the G-code from this test file Traces

I will start by importing the PNG file (Trace).

Importing the png

Then I will choose Isolation settings to add my bit details and the passes I need to perform.
Now I will choose the bit settings (Spindle speed, feed rate, plunge rate, and also the depth of cut)
Now I can export my G-code to be executed by the machine.

Gcode export

Settings¶

[for some of those settings there are different values for the trace milling process and outline cutting process. Mention both]

Setting	Milling	Outline
Feed:	150 mm per min	200mm per min
Spindle speed:	8000RPM	8000RPM
Plunge rate:	60mm per min	100mm per min
Depth of cut:	0.0532mm	1.8mm
Milling bit used:	0.1mm V-bit	1mm Endmil

Machine setup¶

For the setup I’m using FR1 single side board already stick to the bed using double face tape, the machine has underlay bed pre-made from wood and surfaced. In the lab the only available bits are V-bits (o.1mm, 10 degree) so this is what we are going to use today

Bit Used Bit Installed
Zero the Z-Axis

picture of the machine milling

Milling¶

Outline¶

I used (1mm endmil)

Results¶

The result was not as I expected, I thought reducing the feed rate with minimum plunge would give better result but I think there is more than just one variable affecting the quality of the result, Also the tool precision is important player in this situation.

In addition to that I expected better finish with no rough edges and I thought the 0.1 mm bit will be able to mill the last 3 lines but unfortunately it did not. Also, one of the problem I realized that the board stock plays a big role in this (My boards stocks looks dirty,and full of scratches) {they got oxidation because of bad storing condition as they are not well covered and they are exposed to humid air with direct sun some times}.

Result 1 made using mods

The workflow for sending a PCB to a board house¶

select one of the board houses for example PCB Way, or jlcpcb or others, Download the gerber files for the Quentorres board here, Go through the process of attaching the files in the board and getting a quotation for it.

screenshot of the process

In OSH board house site there is limited options to choose from.

screenshot of the process

[The process of requesting from OSH board house was smooth but it took time to process the board, But I liked the purple color it looks great, Also there options on the board is limited.]