Tuesday, January 22, 2013
Laser Cut Circuit Boards
I've had my laser cutter (Full Spectrum 40-watt CO2) for about 1.5 years - and over that time have spent a good amount of time trying to make circuit boards on it. To be clear - I wanted to cut circuit boards. Others have used their lasers to remove resist - to ultimately chemically etch boards.
The barrier was cutting the metal. I tried various tricks to cut copper - with little luck - even with unimaginably thin "copper leaf".
Then an employee of a local commercial hackerspace mentioned he'd cut .001" stainless steel shim. Stainless isn't solderable - but it made me wonder if mild steel could also be cut (which is solderable). Turns out you can! (stay tuned for a future blog post on cutting metal with lasers...)
It's taken a bunch of tweaks - but I can now reliably produce boards that are good enough to be used with 0.1" DIP components.
All is revealed in this video:
Quick summary (step-by-step / more details in video):
1. Attach .001" steel shim to cast acrylic sheet with mounting tape (leave paper backing on acrylic)
2. Cut out though-holes and board itself at 6.5 mm/s (2 passes)
3. Cut traces at 15 mm/s (2 passes)
4. Peel off non-trace segments from board surface (including tape and paper backing)
5. You have a circuit board!
Fast - can make a simple board in only a few minutes
No chemical etching needed
Boards can be any color acrylic comes in - including transparent!
Laser can be used to cut through-holes / cut the board out in any shape
Steel isn't a great conductor / may be an issue for some circuits
Boards are not as sturdy as etched ones
Traces limited to minimum of around 1/16" wide - not suitable for SMD
Soldering smaller (DIP) components can be a bit finicky
Click here to download the SVG for the 555 LED flasher
555 LED Flasher Circuit Details:
+Vin: About 3v (depending on LED)
R1: 10k ohm resistor
R2: 10k ohm resistor
C1: 33uf electrolytic capacitor
LED: An LED
This board was manually designed in Inkscape. I'm very interested in how it goes if anyone tries this process with a board designed using EAGLE or other real software.
If you try this project - please post your own tips / tricks here!
Posted by Rich Olson at 1/22/2013 03:13:00 AM