Showing posts with label homemade. Show all posts
Showing posts with label homemade. Show all posts

Monday, December 17, 2012

Laser for PCB Prototyping?

I've had a great time working on circuit designs in Eagle the last week or so-- after my surgery, my sciatic pain is mostly gone and I'm able to concentrate again! Still, I'm mostly confined to the neighborhood and can't lift or bend or exert myself for another few weeks, so I'm happily plugging away at a few projects, the main one of which is my latest coffee grinder timer.

The timer PCB's odd shape was dictated by the enclosure's design, resulting in a 100mm x 74mm board. It needed to be double-sided, but traces were made wide and vias were kept to a minimum in the interest of home prototyping. I've had great success with toner transfer in the past, but not for 2-sided boards, and not for anything large.

A PCB-production process I've wondered about is using a laser engraver to remove an etch-resistant layer on copper before normal etching. The best and most successful example I've found is on Instructables: "Custom PCB Prototyping using a Laser Cutter," where the author uses flat black Krylon indoor/outdoor paint as the resist.

The example (at right) shows a single-sided board, but I'm primarily interested in using the process for excellent top-bottom registration. Before attempting the large board, I will first try some small pieces with test shapes, then I'll try a double-sided ATmega32u4 breakout board (my own design), then Grinder Timer 5. Stay tuned...

Tuesday, November 13, 2012

Handmade/Homemade Board: "My Arduino III"

My Arduino III by Carlos RodriguesI love homemade boards, and this layout is by Carlos Rodrigues is lovely!  From Flickr:
Construir o meu próprio Arduino, fase 3: alguns upgrades.

Tem agora melhor protecção contra ruídos na alimentação, reset automático ao iniciar um upload, protecção contra excesso de corrente no USB, e o bootloader do Arduino Uno.
Translated by Google:
Build my own Arduino, phase 3: a few upgrades.

You now have better protection against noise on power, automatic reset to start an upload, protection against excess current in USB bootloader and Arduino Uno.

[diagrams]