First foray into homemade PCBs
May 14, 2012
**Update at the bottom.
Alright guys/gals, it has been a coons age since I posted anything even remotely useful of my own. I have managed to break that trend with this 'bitty blog, somewhat. I say somewhat, because, everyone and their brother has posted a how to about DIY PCBs. I will attempt to offer some bit of information that others have not, doubtful. :)
My foray started with a need to make an easy to set up brain for some smaller bots that I want to build. I am a PIC guy, because, I started looking at microcontrollers a good many years ago. And, to begin my robotic journey I had planned to build a hexapod controlled by an 8 pin PIC. I wrote a quick program to control the servos and found I would need a 12f683. With those thoughts in mind I made some decisions about the layout of the board. Hindsight, I failed to include bolt holes to mount the board.
**Note: many of the following images can be clicked for larger images.
Onward, I often use Ubuntu as my OS. That said, I ran across gEDA a few years back and had not heard of KiCAD. With my board idea in my mind I laid out a schematic that should meet my requirements.
Nothing terribly exciting there. Voltage regulator up top fed by a 2 pin header. 3 pin headers on all of the I/O. An 8 pin PIC in the center, and an In Circuit Serial Programming (ICSP) port at the bottom. Time to make artwork.
Now I have artwork for a board that is 1.62" x 1" (41.1mm x 25.4mm) and it holds all of the bits and pieces that I hoped for it to.
I used Inkscape to lay out a sheet to print. With my sheet, I have 12 copies of said board laid out to fit on the board I purchased at Radio Shack. **Note to self: don't use double sided copper clad to make single sided boards, if you don't have to. The etching process takes FOREVER.
With the printing done, it is time to layout all the assorted materials, copper clad, scuffing material, alcohol, Muratic acid, Hydrogen Peroxide.
Radio Shack double sided copper clad
Obligatory artwork on copper clad pic. This pic looks like it was taken before the iron set to Cotton setting was mashed all over it and then a 3/4" dowel rod was used as a make shift laminator roller with the iron on top. After 3 to 5 minutes, closer to the 3, the board was allowed to cool and then tossed in some cold water for a minute or so and off came the paper.
The after water pic. If you look close, there are still drops of water on the board. Also, if you look close, you will see errors here and there. Second closer pic.
Once the artwork was etched, I used a copper pot scrubber to remove the artwork to reveal the purdy copper underneath. If one pic isn't enough, check this out.
UPDATE: upon inspection, I did indeed need to mirro the silkscreen so that it will be able to be ironed on in the proper orientation.
This is it for now. I will get back with you once I have some more useful info. Like actual parts in boards.
Between kariloy and hoff70, I decided I better get off my lazy butt and finish up at least one of my boards. Using kariloy's idea of pins to align the silkscreen, I managed to get the silkscreen layer on pretty straight.
The holes are mal-aligned, because I drilled them by hand with my dremel. I can't be as much of a man and use an Archemedes drill like kariloy did. :)
And now, the top view.
One final pic that I am a bit ashamed of.
I will update this if I make something go *POOF* . Otherwise, I will call this a reasonably complete blog.