$5 Upcycled Desk Clock

Last summer I came across a collection of car parts at a garage sale; instrument clusters, lights, gauges, and some digital clock displays.  For $5, I became the proud owner of a JECO Japan, vacuum fluorescent clock display.  The plastic housing held all the clock electronics, membrane buttons for setting the time, and a four-pin connector.  After powering it up, I realized one of the pins could be used to dim the display, which is a pretty nice feature to have.

I’ve worked on it off and on for a few months, but finally decided to finish it this weekend.  On Saturday, I tweaked some dimensions and laser-cut the final enclosure.  I wasn’t happy with the button holes and text I had on the front of the first iteration, so I got rid of them for the final.  You can adjust the time by slipping a jeweler’s screwdriver or a paper clip through a gap in between the plexiglass sides and pressing the buttons to add hours or minutes. 

I added a small single-pole, double-throw toggle to switch between bright and dim, then soldered the connections before closing it up.  The whole thing is clamped together by a single #10-32 machine screw and a wingnut.  The final result doesn’t look half bad.

2014 RPM Challenge: Accepted!

Today is the first day the 2014 RPM Challenge, which is the National Novel Writing Month of music!  The goal of the RPM challenge is to compose and record an entire album during the month of February! I accepted the challenge by dusting off my Cacophonator and Mohogonator, and got to work making music after dinner today. As today also marks the 50th anniversary of the Beatles invasion, this project drew inspiration from the Beatles’ back catalog!

RPM_Challenge

I used the dynamic duo of Cacophonator and Mohogonator with Auditionator (i.e. Adobe Audition) to record a session for about 12 minutes at a blazing fast 192kHz sample rate.  After chopping the recording into individual tracks, I digitally slowed them down to the customary rate of 44.1kHz, thereby expanding the work to its final ~45 minute length.  For inspiration while I was recording, I listened to Beatles songs sped up to 435% (which is 192/44.1) of their customary speed.  My tracks needed a bit of post-processing: on some of them I chose to bump the pitch back up an octave or two and add “Beatle Fades” to the beginning and end.  Anyway, within twenty minutes after the recording was made, I had edited the songs and uploaded them.  You’ve read that correctly, in less time than it takes to listen to the pieces, they were composed, recorded, processed, mastered, named and uploaded.

Today is also the 50th anniversary of the first Beatles song hitting #1 on the US pop charts: “I Wanna Hold Your Hand.” This whole project was inspired by this apparent coincidence in timing, and each track was directly inspired by listening to the sped-up Beatles original.  I hope you enjoy each of the 11 tracks I created!

While My Cacophonator Gently Weeps
Got To Get You Into My Cacophonator
All You Need Is Cacophony
With A Little Help From My Cacophonator
Sgt. Cacophonator’s Lonely Hearts Club Band
Cacophonator Came In Through The Bathroom Window
Lucy In The Cacophonator With Diamonds
Got To Get Cacophonator Into My Life
A Hard Day’s Cacophonation
You’ve Got To Hide Your Cacophonator Away
Cacophonator Wants to Hold Your Hand

It may be more convenient to listen to the entire album: “Cacophonator 2: Electric Boogaloo; A Love Tragedy in 11 Parts” on the RPM Challenge site’s Cacophonator page. Just scroll down to “My Player.”  There is plenty of February left: I encourage everyone to participate!

Home Environmental Sensor Array (Phase 1) Finished

After six months of working on this on-and-off, I installed my home environmental sensor array (HESA) in my basement. Basically, it looks for water in the basement. If it detects water, it shuts off power to my water softener (assuming that the softener is or will, dump more water into the basement), and sends me an email.  The HESA has a Raspberry Pi to detect water and control the PowerSwitch Tail relay.  It also connects to the internet via my home network.

HESA

This is phase one of my HESA project. The device I built in this phase will only detect water. Future phases will add the capability to detect more things and be more interactive.

This is basically, my first real Maker project.  I learned or practiced many Maker skills like soldering, basic electronics, and CNC routing. I made my own PCB (that I did not end up using). I did some basic metal work with a jig saw. I learned how to use several software tools for CAD and design. I learned to program in Python. And I had a lot of fun doing it.

Several Makers at the Milwaukee Makerspace helped me with this project. There is no way I could have built this without them. Thanks to anyone who took time to help me move this project forward.

Wiki project page

Blog

Raspberry Pi Project Ended

I’ve really struggled with the Raspberry Pi Project. As I posted earlier, the Raspberry Pi kept killing the file system on the SD card. Pete traded me for a different Pi, which behaved much better, making the card last at least long enough to get the operating system and other software installed. Yet the Raspberry Pi continued to corrupt the file system if left running for longer periods. The latest time it totally killed the SD card; I couldn’t even reformat it on my computer.

If I include the Pi in the traveling mascot, I’m convinced it will not survive the inevitable rough treatment. The only other use I can think of for a Raspberry Pi in a travelling mascot is as a home base server for the mascot, publishing the travelogues. Yet it’s too unstable for even that task.

I still like the idea of a traveling mascot that can track it’s own travels, but I’m convinced that building it around a Raspberry Pi is not the proper foundation. I really like the little GPS unit that came in this kit, and will try to build a scaled down version of the traveling mascot with a USB interface to hook up with any computer for collecting data.

Thanks again Adafruit Industries, we really appreciate the kit, and we’ll continue to work with the parts on other projects. Like vultures, some other members have already picked off some pieces of the kit for their projects.

Lighting Control Upgrade!

IMAG3517In an effort to make the lighting control system more user-friendly, the original board-mounted switches have been replaced with a laser-cut zone map! Instead of looking up which zone number corresponds to a particular bank of lights, each location is now identified by a green LED pushbutton.  You can read more about the lighting control system and how it’s been evolving on our wiki: http://wiki.milwaukeemakerspace.org/projects/mmlc

Weekend Project: Simple rocket launcher

For years I have wanted to make a simple device to launch a model rocket. This Saturday, my son Tim and I built it at the Makerspace. The launcher consists of a project box with some external connectors for the wires that go to the rocket, an arming switch, an LED to signal that the circuit is good, and a launch button. It took about four hours to make including several mistakes and backtracks.

We tested the circuit and it works as planned. The real test will be tomorrow when we attempt to launch some rockets at the park.

IMG_20130615_155201

Halloween Skull Project

I want to open my first blog post with a statement that continues to impress me: Milwaukee Makerspace is a wonderful place! I mostly show up for the free meetings.  MMS provides an excellent environment to be social, to learn (happens every time I go!), to teach (when I can!), and to get the creative juices flowing.

I had recently started working with Arduino (after a failed run at Microchip’s PIC series of microcontrollers), and was making progress quickly.  I learned how to read infrared remote control codes, how to use an infrared motion sensor, and how to control servos. What I did not have, was a sense of direction as to where to go with all of this!

After listening to the Bay View Neighborhood Associate pitch their idea of MMS helping with the Pumpkin Pavilion, and listening to Royce Pipkins describe his idea of animatronic pumpkins singing along to a song, I was struck with my own idea: an animatronic skull.

Thus, it was born!

http://vimeo.com/55121596 <- Link to the video

I’ll post more details in a following post about how I built this guy. :)

Many thanks to Royce, Tom G., and Ed C. for their help on this project!

Hack-A-Lantern: DIY Salvaged Zombie-beatin’ Flashlight!

Recently, I was hanging out at the Milwaukee Makerspace, working on a simple project, when a fellow Maker offered me a used 5AH lead acid battery.

The project I was working on involved using landscaping lighting, and right there on the “Hack Rack” were some old computer power supplies. Hmmm. We also happened to be talking about Zombie movies and TV shows, when it all clicked – I have the skills and materials to build an electric lantern from scratch using just the materials that are right here!

The project started by taking apart a computer power supply. I snipped the wires from switch and power cord connection close to the circuit board, so that I would have plenty of wire still soldered to the switch. After removing the circuit board and cooling fan, I had a nice empty box to use as the case for the lantern.

Next, I snipped out the fan grate, to allow for the 12V 11watt landscaping light bulb. These things are designed to run on 12AC from a transformer, but nothing is stopping me from running it on a 12V battery instead!

I crimped on a couple of spade connectors onto the wires from the switch to go to the battery and the bulb. I also wired the power port so that it was unswitched (always connects to the battery) that way, I could use it to recharge the battery without having to open the case. I would just clip the external battery charger that I already had to the two pins of the port.

Once the wiring was done, I checked the connections, turned it on and off a couple of time, and then glued the bulb in place with silicon.

A key feature of a lantern (as opposed to a flashlight) is that it has a distinct handle on the top, which the lantern hangs from. When I’ve made handles before, I’ve usually used a pair of bolts with spacers and some sort of cross-piece of wood or metal. However, I didn’t have anything like that handy, and it didn’t seem to fit the theme of the lantern either.

I DID have all the extra wiring from inside the power supply. The main bit of it was already bundled and had a nice connector on the end. I drilled two 1/2″ holes in the case cover and ran the cable through it, then back through the other hole, and pinned it in place with a few zip-ties.

I also glued two bits of foam on the inside of the case to cushion and help hold in place the battery. With that I put the cover back on and reinstalled the four cover screws.

There ya go! A lantern made completely from repurposed, recycled, and salvaged materials! Whether you like tinkering, being ready for the zombies, or just like being prepared, the Hack-A-Lantern is for you. Why don’t you try making one and see what you come up with!

More DIY Eco-Projects at http://ecoprojecteer.net

My neverending quest for quick turnaround prototype PCBs

For years I have dreamed of a fast way to prototype PCB for projects I am designing.

20 years ago I was using rub on drafting tape and stencils – slow and spotty results.

I tried to modify a plotter to plot resist directly to a PCB – no luck.

Magic markers – I’m no artist.

5 years ago I hacked a laminate router by tapping into the stepper controllers and adding a better Z axis – It can rout boards ok, but takes some tweaking.  It only does fairly wide traces.  But its great at drilling holes!

2 years ago I tried the inkjet printing systems – lots of smeared wet ink and poor registration, not very effective.

I opened up a laser printer and tried to get a board to go through it – almost worked, but the fuser was to narrow to take the board.

Although I haven’t found a fast system yet, I get by with the PNP Blue material and a good laminator.  Although I am regularly disappointed when dust, not quite clean boards, minor wrinkles and other issues leave gaps in traces that need touching up.

Which brings us to the latest attempt:

Now that the maker space has a small laser cutter I am trying to find something I can coat a board with and either burn away or melt onto the board to act as an etch resist.

Early attempts with paint had moderate results – our laser cutters on only 25W so it didn’t burn it cleanly.  I have heard that using flat black paint and a more powerful laser works.

Paste wax and markup fluid weren’t dark enough for the laser to vaporize (thinking of trying black crayons)

The latest attempt uses laser printer toner (just like the PNP only skipping the printing and iron on steps.)

The problem is how to get an even coat on a board without it blowing around.  Static electricity has potential (just like what they do inside a laser printer) but I don’t like the idea of a 5KV power supply exposed and handling powered toner is an automatic mess.

So for the first attempt I mixed the toner with rubbing alcohol (30% water).

Messy stuff!

I painted it on with the tongue depressor but it seemed to coat evenly and took only a few minutes to dry:

It mixes well and paints on fairly easily, here are some sample prints I did at various power and speed settings.  I cleaned the board fairly aggressively with paper towel and rubbing alcohol.

None are quite clean enough to become PCBs but they are getting close.

Although the toner paint looked dry, it may still have had some water in it.  I plan on trying a batch with denatured alcohol (100% – no water) and see if it works better.

 

2/16/2012

Updated progress

I have been trying a number of materials and methods to make my fast turn circuit boards.

I’ve decided that last toner is too messy and there are too many variables to create a repeatable process.  So now I’m trying various other masking materials:

 

Black and white spray paint – it works ok, but the ash left behind by the laser resists the etchant and leaves you with a poor etch.

I also tried tape:  Painters tape, electrical tape, clear and brown box tape.  The masking tape worked ok until the etch was slow and the tape started to dissolve.

I held a few of the boards up to the light so you can see how it etched:

 

 

 

 

 

 

One of the other members of the space found someone who had made the black paint work.  The process is to do 2 passes with the laser – the first burns off the paint, the second burns off the ash!  Then you wipe the board down with rubbing alcohol to clean off any residue.   Here is a set of 3 projects I lasered and etched at once:

This board turned out rather well, I had some trouble with the etchant taking for ever so lost some of the detail on the lettering, but the boards came out nicely.  I should get even better results on the next project.

In an attempt to speed the entire process up I tried to drill holes with the laser cutter from the back of the board:

   Not very good results!  After about 6 passes it still didn’t cut through thin PCB material and stunk and smoked the whole time!

 

 

 

 

 

 

So instead, I used the laser to cut wholes in a small piece of acrylic to use as drill guide:

 

 

 

This gives you a pattern to follow using a Dremel and the holes wind up in the right places and nicely lined up.  I drilled 2 holes in opposite corners of the board and used the leads from resistor to line up the template and board and hold them together while drilling.

 

 

 

This image shows the template attached to the board and about half the holes drilled.  This worked very nicely!  The only problems was small disks of acrylic getting stuck to the drill bit (you can see little craters on the left side of the board where these came from)  I had to clean the drill bit twice to drill the whole thing.  Either bigger holes or a different plastic might fix this.

 

This is first of the 3 boards I put together and it works just fine.  It is a level translator for the encoder you see in the holder.  The encoder will be attached to the drive motor in my electric car and feed back motor position to the controller.  The encoder is 5V and the controller wants a 15V signal.  The test bed uses a 15V power supply and LEDs on the 4 quaderature outputs.

Encoder test video

Rotary Encoder – built into motor for Electric Car

My electric Dodge neon uses an AC motor and an industrial motor controller.  I upgraded from m 1984 motor controller to one less than 25 years old (actually less than 5.)

The new controller does much more than the old one and has the ability to do some fancy tricks.  At the moment I am running it in “sense vector” mode.  The controller senses the position of the armature by monitoring the current in the field coils.  This works great…   as long as the motor is spinning.  From a stop it tends to get out of sync, but there is a cure!

The controller can use a quaderature encoder so the encoder can read the position of the armature at any speed.

To add an encoder to the motor I decided to try a chip amde by Austrial Microsystem AS5040.  This chip senses a magnet near the chip and calculates the position of the magnet and can generate multiple output:  PWM, binary via I2C, and quadurature!

I bought a few of the chips and built a surface mount board to hold the chip and a few LEDs to display the output.  The first two version had a few problems but the 3rd time was the charm.

 

 

Thanks to Royce for working out the process for surface mount PCBs.

 

The final version had to be small enough to fit in a depression in the end of the motor cap.  The sensor centered and the whole board insulated (clear enamel)  since this is a grease pocket

for the rear motor bearing.

 

 

 

 

The magnet is mounted to a bolt that is threaded into a tapped hole in the back end of the armature.  It took a while to the position right (it needs to be within a few millimeters of the sensor) hence the nuts and washers.

 

The cable is brought out of the motor through a small threaded hole (it was an alternate location for the grease fitting.)  The hole is filled with epoxy and the wires go to a DB9 connector.   I built a small test board that shows the quadurature signals (4 round LEDs) and the status outputs from the chip (the two rectangular LEDs)

 

 

 

 

 

The motor controller puts out 15V to power an encoder and wants A and B as well as inverted A and B signals.  The circuit includes some NPN transistors along with a voltage regulator and a few capacitors to tie it all together.  I put the schematic for both the sensor and test board on one schematic so I could make both boards at the same time.

I installed it in the car today, but still need to put a few more parts together to run it.

 

 

 

DOH!

It doesn’t work!

Ok, so the electronics work fine, it talks to the controller.

But it tops out at 256 pulses per revolution and the controller needs 1024.  It was a minor confusion between terminology.  The sensor detects 1024 positions, but to generate quaderature it uses 4 positions per pulse output.

Back to the drawing board.

 

I picked up a commercial shaft encoder on ebay for 50 that outputs 1024 PPR but it only works at 5V, so I’ll need a level shifter board and connector adapter.

Oh, yea, and I need to put the motor again, take out the old encoder, bring a shaft extension through the back grease pocket, add a grease seal and couple it to the encoder.