This week is about learning to fabricate a PCB, not necessarily design it.
This week is about learning how to fabricate a PCB.
### Page Summary
1. Summary
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@@ -40,12 +40,12 @@ It is important to note that both these images are at 1000 dpi resolution in png
Next, these png images need to be converted to tool-paths for CNC machines to follow. [Fabmodules](http://fabmodules.org/) and [Mods](http://mods.cba.mit.edu/) both, developed by the Fab community can be used to make the tool-paths. They run in the browser.
I'm not sure why these errors occured. I try using FabModules with the same files and same settings. And it works perfectly. So I guess Mods has a different way to read these files.
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@@ -66,7 +66,7 @@ I'm not sure why these errors occured. I try using FabModules with the same file
-**Number of offsets: 4** this is the number of paths around the traces, if its too little soldering components is difficult, if it - too much, it takes a long time to mill, 4 is just enough (-1 to remove everything completely)
-**Offset overlap: 50%** The overlap between two paths, to ensure no material is left with error
With these settings, I **calculate** the toolpaths for the traces and **save** the rml file.
Making the outline has the same process except the following changes:
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@@ -79,26 +79,26 @@ Making the outline has the same process except the following changes:
Since the cut depth is 0.6, to cut through the 1.7 mm stock, it will run the path 3 times till it cuts through the entire thickness of the stock. This can be seen when you **calculate** the toolpath.
Using the XY and Z settings in the centre of the panel, move the Z to maximum to make space for fixing an endmill manually. Loosen the collet with a hex-key, insert the 1/64in endmill and tighten it snugly.
Next move the XY to where you want to define the origin point. The origin is at the left bottom of the file. So pick a spot close to the left bottom corner of the board. Bring Z close to the surface using 100x and 10x steps. When it is just above the stock but not touching it, loosen the collet while holding the bit, lit it gently fall on the stock and still while holding the bit in one hand tighten it with the other. This is one way to ensure a proper Z origin on the top of the stock surface.
Now, on the v-panel set the XY origin and the Z origin here. Since we've adjusted the feeds and speeds in FabModules already, we do not change them here. Select **cut** and then on the pop-up window clear all files in the output file list before adding the traces rml.
Select the traces file and hit **output** after closing the lid of the machine.
The spindle will now start and run the toolpaths. The v-panl allows to **pause** the file, **view** to check if the cutting is alright, and then **resume** after. Doing this in the beginning of the cutting helps save time in case of improper settings.
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@@ -106,48 +106,47 @@ Here is how the machine should sound while cutting correctly.
After the job finishes, move the Z maximum again and change the endmill to a 1/32in for cutting the outline. Use the same process as above and set a new Z origin. Do not change the XY origin this time, as it needs to match the previous job. Upload the outline rml to the output file list and start cutting.
This is how the cut result looks at the end of both jobs.
First I inspected the board visually to check if all the traces were clear from solder bits and all the connections were clean. I also checked if all components were soldered on the correct footprints and in the correct orientation.
First I inspected the board visually to check if all the traces were clear from solder bits and all the connections were clean. I also checked if all components were soldered on the correct footprints and in the correct orientation.
Next, I use a multimeter to check the resistance across resistors and voltage across VCC and GND. Everything seems alright.
Next, I make assemble a ribbon cable, 6 thin cables connected side by side with female headers at both ends. Trick is to keep booth ends in the same orientation to correct and quickly attach the headers. After presseing them lightly, I used a mallet to fix them properly.
Next, I make assemble a ribbon cable, 6 thin cables connected side by side with female headers at both ends. Trick is to keep booth ends in the same orientation to correct and quickly attach the headers. After presseing them lightly, I used a mallet to fix them properly.
### Installing software packages
To program the board, there are steps you need to follow to install the development environment first. I follow them from [this tutorial](http://fab.academany.org/2020/labs/uae/students/fatima-alhashmi/week5/week5.html) and [this guide](./images/ep/avr_steps.pdf).
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@@ -156,16 +155,15 @@ Installed [homebrew](https://brew.sh/) package manager. In a terminal window pas
