Archive | April 2011

Powering the Laser: Part II

The next thing that needed to be done was get a power supply. I was using 9v batteries for a little while but they don’t last very long. I’ve needed a variable power supply for a while, but they were always a little out of my price range. So I went to Electronic Goldmine and picked up a nifty 0-12V DC power supply kit for a little over $11.

I haven’t decided if this is going to be attached to the CNC machine or if I’m going to build a constant 12v power supply. If it’s going to go to the CNC, I’ll have to stick a relay or transistor in there so it can be turned on and off by computer.

I will have my own pics up soon instead of all these product photos!

Powering the Laser Diode

Laser diodes need a regulated current. If you just hook one up to a 9V battery, It’s going to suck out as much current as it can. This will cause it to heat up and burn out. One of the components that seems to be used with lasers is the LM317 regulator. It looks like a transistor.

I tried putting together a LM317 Constant Current Circuit on a piece of perf-board, but something went wonky with my schematic or a component I was using. So instead of going to Radio Shack again, (god, I hate that company!) I decided to order a pre-assembled current regulator that would theoretically fit inside the laser enclosure I just bought. It’s called the RkcStr Micro-driver.

It turned out not to fit into my enclosure, but I don’t mind. I think it will just make it easier to heatsink. If not, I can file it down later.

First Step: the laser diode

Getting the laser seemed like the first logical step toward building a laser cutter. First, I disassembled a broken DVD burner that was in my basement and took out the laser diode. It’s wavelength is 650 nm (nanometers). I searched a couple of websites to find an enclosure and lens for the diode, but found that I could get a pre-harvested blu-ray laser diode (wavelength: 405 nm)  already inside an enclosure for a couple dollars cheaper than an empty enclosure. I don’t know why, but I didn’t ask questions. I just took the deal. I got the laser from High Tech Dealz.

Hello world!

This blog is intended to document the construction and development of things I make. Currently, I’m building a CNC laser cutter from scavenged parts, parts bought from hardware stores, open-source electronics (such as an Arduino board) and free software (software libre). Throughout the development of this project, I expect to run in to problems, solve them, and document them on this site so that others can benefit from my experience.

When this project is completed I will move on to another one and do the same thing. One thing I hope to do with the laser cutter is construct parts for a 3D printer. I will also post side projects as they come up.