Laser Engraved Declaration of Independence

Rick Osgood creates all kinds of cool things, most recently a professional grade vacuum former from scratch.  So when he was looking for some help creating a project for Independence Day, I jumped right in.

The idea was to create an edge lit Declaration of Independence from acrylic.  I’ve done a lot of work recently with similar projects.  There were two options for making the acrylic part.  Engraving this on my CNC would allow the acrylic part to be up to 28″ x 16″.  But the writing on the Declaration of Independence is extremely detailed.  I’ve had problems with small engraving on the CNC, and it would take forever to do that much engraving.  My laser is limited to 14″ x 8.5″ which would make the smaller writing nearly impossible to read.  But it handles tiny engraving with ease, and can quickly zip through a part like this in about an hour, so that is the approach we took.

I handled the acrylic part, cutting out a piece laser engraving it, and finishing the edges.  The lit edge works best with a high polish the let in the light.  Putting a rough finish on the other 3 edges causes them to illuminate nicely.  The end part turned out great, and shows how well a cheap Chinese laser can actually do when dialed in properly.  I’ll share more of my experiences with the laser engraver/cutter in a different post.

DOC

Rick put together a mini-Arduino and RGB LED strip, in a wooden base.  Then he did a slick trick of vacuum forming plastic over the base to give it a professional, finished appearance.

Check out Rick’s video showing the entire project.

http://youtu.be/hqYaqPpJO9s

Basic Arduino Projects

I’ve been doing a little messing around with Arduino’s recently.  If you haven’t heard of an Arduino, it is essentially microcontroller development board, designed to be as simple as possible for someone to get up and running.  In the 8 years since it was first developed, it has become the standard development platform for many hobbyists.

0178s

This is a project I had less than a single day to complete from start to finish.  That is from initial concept until stepping on a plane to California to demo a working product. Normally I would design and build up a custom board, program a micro in assembly, make a 3D model of the mechanical design, and machine a custom case.  None of that was an option in the limited time frame, so I rushed out and picked up an Arduino from Radio Shack and decent looking junction box from Home Depot.  Even having never used an Arduino before, within a few hours I had a completed product.  A few LED’s and an ink jet printed face plate and the result was remarkably professional.  Unfortunately due to the commercial nature of this, I can’t show too much of the final result.

0179s

This application is a perfect fit for an Arduino.  There are 4 LED’s that flash and fade to give user feedback.  There is a button input, as well as a light sensor.  An op amp and trim pot are used to amplify the output of the photocell.  There is also a relay to switch a line voltage device.  This is soldered together on a proto-shield sitting on top of an Arduino Uno and powered by a 9 volt battery.

0176s

Here is another example project.  This is an Arduino Mega 2560, which has a lot more I/O  and memory than the Uno.  Connected to it is an 16×2 LCD display from Adafruit.  What is notable about this display is it has an RGB backlight, meaning you can change the color to anything you want, including fading from one color to another.  This is also a ‘negative’ display, so the characters light up instead of the background.  I’m a big fan of negative LCD displays, as they are easier to see in a wide variety of lighting conditions.

I tossed this one together at the Eugene Maker Space, hence the text on the screen.  The number 23 is simply a second counter just to let me know the code is still alive.  The trim pot on the protoboard is for the display contrast.

This used a lot of I/O pins (13!), but it is possible to do this with 9 by going with a 4 bit bus.  There are also display options that use I2C or SPI to cut the number of pins down even further to make it more practical with a small microcontroller.  Since I had a Mega 2560 with 54 I/O pins, I made it simple on myself and used a full 8 bit bus.

I really like the Arduino platform.  While it isn’t perfect for all applications, it serves the role it was designed for extremely well.

Eugene Maker Space Make-O-Rama

Spent a great Saturday at the Eugene Maker Space, where I am a proud member.  They were hosting a Make-O-Rama, basically an open house.  There was a focus on making tools to make other things, but there was a wide variety of cool things on display.  There was a steam engine, a couple 3D printers, robots, microprocessor projects, flashing lights, and Bob’s homemade laser cutter which is nearing completion.  For the less engineering oriented, there was a design for a non-swarming bee hive.  A tuned, steel drum made from propane tank made a brief appearance.

My homemade CNC router made its first public appearance, and I set it up to cut of Eugene Maker Space logos.  Although not fully tuned and aligned yet, and still using a temporary router and mounts, I was quite happy with the quality of its first real parts.

Here is time-lapse footage of the event.  My CNC router is the big, blue box that appears about 11:30 in the bottom-left corner with the bright and sometimes changing-color lights.  I’m one of those guys in the cool, white, lab coats!