Project of The Week: Beetle-Kill Pine Door

Howdy Hackers!

Due to high rental costs in Boulder, my roommate and I decided to rent out the living room! It’s a pretty sweet living room, has it’s own separate entrance and a balcony. It made sense to us because the kitchen is the size of the living room with a balcony and entrance as well so we decided to efficiently use the area as a communal space/kitchen.We met an amazing couple and before moving in we all decided building a door to make the living room separate would be a fun project.

Thanks to the amazing Woodshop available to SSD members, this project came to life!

Behold the end result. An 80 pound door made out of beetle kill pine.


We got all the wood at Home Depot for under $100 dollars. We figured if we’re going to have a door let’s go all out and make it legit and awesome, you know, something we could all be proud of- not some pre-made manufactured door.


Home depot had these slatted boards that slide into each other, that made life a lot easier! But we still needed top and bottom trim and an internal support system.


The internal support system turned out to be the most important aspect of the door and took a lot of measuring and planning. The slatted boards have a tendency to float away from each other so the width of the door kept expanding. Once we pushed them as tight together as possible we were able to get the correct measurements for the support system and tack the front and back panels together accordingly. We found some pallets and used the wood from that.


This is a solid knob that we got from Resource for 10cents!


The circle is for where the knob was going to go. The middle support goes on top of that so the screw doesn’t go too far out the front of the door.



The screw had to go through the middle support board and through the front panels. It turned out that the knob when screwed on as tight as possible was perfect! Meant to be I suppose=)


After securing the knob The back panels were ready to go on. I used a pneumatic finishing nail gun (rented from home depot across the street) to secure the front and back panels to the internal support system. The reason we used finishing nails instead of Screws, bolts, or hammerable nails is simply because of aesthetics. Now from a few feet away it looks like the door is held together by magic;)


The top trim needed some support so I cheated the top and bottom support upward until it was halfway on the panels and halfway through the top trim. As you can see the top trim comes out a little bit, that was so I could put flat boards on the front. This way looks cleaner and the internal support system doesn’t show.


Just cutting the front trim as before mentioned.



This part is incredibly important to get right or the entire project goes under. If the door drags along the carpet it could break the hinges so it’s important to line up where the hinges go correctly. To do this we put a scrap piece of board the same width as one of this boards (~3/4″) underneath the door and lined it up with the cut I made against the wall to use as reference. My roommate had a Dremel Multi-max oscillating tool which had a wood trim attachment, it is meant for precision cuts and that’s what I used, a router probably would have been good too.


The screws that came with the hinges were not even an inch long so we used 3″ long self tapping screws we got from McGuckins(cost like 4 bucks for 50 of them) We screwed those bad boys in and BAM! Door.



Happy Hacking!





Member Project of the Week: Hacking a bargain LED lantern

I’ve often found there’s always a bit of “Tim the Tool Man Taylor” in every hacker.  That is, we all endeavor to make something bigger, badder, and more powerful than anything in it’s class.  Such is the thinking behind this project.  My Mom is an avid shopper, and she is often finding all sorts of bargains.  This time around, she found a camping LED lantern, with 12 LEDs, and a marked luminance of about 30 lumens.


When I took it out of the box and powered it on, the light was adequate, but not for an LED freak like myself.  Furthermore, I don’t know who designs these things, but they obviously don’t test their own creations.  The lights were mounted facing up, reflecting off a hyperbolic cone.  Unfortunately this means that the majority of the light would be shining out from horizontal upward into the eyes of anyone near it.  As well, none of the light went onto the surface the lantern was sitting on.  These two aspects rendered it quite useless as lanterns go.


Seriously, who designed this and didn’t test it?

My mom was a bit disappointed that she apparently didn’t find as good a bargain as she thought, but I reminded her that with a bit of elbow grease and a few cheap components, I could make it better.  You see, the hardest part of making a good lantern isn’t the light engine, it’s the plastic housing.  The ones she bought already had what I considered to be a pretty nice plastic housing, it just needed an upgrade of the light engine.



On opening the battery compartment, I noticed that there was some space in it for extra electronics.


Red arrow shows extra space untouched by the 3 D-cell battery carrier.

Knowing that white LEDs run at a forward voltage of 3.4v, and wanting to not use any type of resistive regulation (to avoid wasting power as heat), I knew that A) I’d either be stepping the voltage down to 3.4v or stepping it up to whatever LED cluster I found.  That meant that i needed space in the lantern somewhere for a regulator.  This little nook had enough volume for many switching converter designs, I just needed to find one to fit it.

I immediately went looking on eBay for LEDs to use, and happened upon a lot of 5 of these aluminium core boards that have three 110 lm LEDs on them.  They’re wired in series for a combined brightness of 330 lm. I picked them up for $8.  However, because they’re three 3.4v LEDs wired in series, they’re rated for 10.2v (the post said 9-12v, but 10.2v works the best).  The lantern has a battery carrier that holds 3 D cells.  This gives me an adequate amount of amperage at 4.5v.  Not enough voltage to directly drive the LEDs, so this meant I definitely would need to buy a boost controller.  Again, eBay serves it’s purpose and I was able to nab these LM2577 switchers for about $2.85 each.



Beginning disassembly


Whenever taking anything apart, make sure you note which screws you pulled from where, and make note of any type of hardware keying like you see here.


Note the red arrow pointing to the key and slot that the designers put in the top. Make sure you keep track of this for later…

When I cracked this open, I discovered that the hyperbolic cone was not glued to the top (bonus!), but would require cutting if i was going to attempt to put it in the bottom (bogus!).


Elemental pieces. Now it’s time for checking if we can invert the cone.

I centered the hurricane “glass” of the lantern on the cone, then used a fine tip sharpie to draw the outline of the bottom of the glass.


Checking the fit, tracing inner circle with fine tipped sharpie.


Cut line now marked with fine tip sharpie.


I cut relief cuts into the circle before attempting to cut the full circle.  This makes it easier to snap off the chunks as you cut them.  Cutting a circle with a rotary blade on the dremel isn’t easy. To make it easier, I put the dremel in a vise so I could maneuver the reflector around the blade rather than the blade around the reflector. Note my use of the blue nitrile gloves.  When handling any type of chromed plastic reflector, you’ll be sorry if you don’t use gloves.  Once smudged with skin oil it’s hard to impossible get them back into a clean state without scratching them.


Cutting relief cuts before cutting along the sharpie line.


Testing the fit.


Testing the fit with the hurricane in place.



Gluing down the cone to the bottom reflector with 2 part epoxy.

As with all higher luminance LEDs they emit a fair amount of heat, which is dangerous for the life of the LED.  They do much better if you attach them to a heatsink.  Junk bin to the rescue! CPU heatsinks are useful for many high power LED projects, and they’re usually free if you can find an older computer to scrap.  This heatsink had two “wings” out from the fan, one of which I’ve already removed with a hacksaw to use for this hack.


Soldering to the aluminium core board is a hassle, precisely because it’s efficient at wicking away heat.  It means you have to dump a lot of heat into the joint just to get it to marginally flow.  I’m not happy with the quality of these solder joints, but they worked.  Oh, and if it wasn’t obvious, solder FIRST, then attach heat sink otherwise you’d never get solder joints to flow.  😉

I added thermal grease between the heatsink and board, and secured the two together with some dabs of epoxy around the edges and holes in the board.


I had to remove the switch and battery contact board in order to wire it up to the new driver board.


I soldered it inline with the regulator.  At this stage, I made sure to adjust the output to match the LED forward voltage, in our case, it needed to be adjusted to 10.2v out.  Since these boards are adjustable, you need to attach the voltage you’ll be working with to the input, and adjust the trimmer pot while watching the voltage on a multimeter.


If you don’t have this in your hacker’s toolbox, go get some.  Epoxy putty is invaluable, as much for being a filler as it is for being an adhesive.  Be sure to use gloves when kneading it though, as it gets sticky and you don’t want it on your skin.


Here you can see the two blobs of the putty that are used to attach the LED assembly to the top.



Drill a hole in the back of the reflector to thread the LED head leads through to the battery compartment.


Threaded the leads down into the battery compartment as I reassembled the top of the lantern.



Here’s where final steps of putting the circuit together take place.



The power board I bought just happened to fit into the switch area without needing to remove any of the plastic.  I always appreciate those little coincidences.


The final product, reassembled.


And finally the two versions side by side.

Two final versions lit up.



All told, the entire mod for the first lantern was around 3 hours for a price of about $6 ($1.66 for the LEDs, $2.85 for the boost controller, and about $1.50 in epoxy and epoxy putty). The time spent on subsequent lanterns was about 1 – 1.5 hrs each, now that I know what I’m doing with the design.  Not too shabby.

So did I save any money over buying a higher lumen lantern that was already built?  Yes, and no.  Yes, in pure dollars.  No in terms of time.  But if you don’t understand why someone would spend the time hacking something that might be easier to buy, consider these points.

Hacking something provides:

  • the pleasure of the challenge to make something better.  It gets the creative juices flowing as you attempt to solve problems.
  • the time spent tinkering (far more relaxing than vegging out in front of the TV, IMHO)
  • the feeling of accomplishment when it works and learning from failure when it doesn’t
  • learning how to do things better when you hack on future items
  • it can push you to learn new technologies and techniques in order to get what you want out of the hack
  • the option to actually have a “good enough” approximation when the desired item doesn’t exist, or is prohibitively expensive if it does.
  • prototyping a new idea based on the initial item

And most of all, sometimes you don’t know precisely what you want, until you’ve hacked it!


Member Project of the Week: The Cyclophone

Ben and I had been talking about building a MIDI controller based off an Arduino for some time now. Then, about a month ago, with Apogaea just around the corner, we started thinking about making an instrument for the Soundpuddle, John English’s spectrum-analyzing dome. We thought it would be cool to build a circular keyboard, where each key would emit a tone which corresponds to a frequency bin on the Soundpuddle. Thus began development on the Cyclophone.

The Completed Cyclophone

The Completed Cyclophone

We did a lot of brainstorming that first week, which included building a couple of prototypes. The first prototype was just aimed at answering the basic questions: Can we reliably send note-on messages over the serial port, and without latency? Can wooden keys give a good tactile response? Will this even work? The result of these first experiments was a little creation that we affectionately call the “cuttlefish”.

The "cuttlefish" prototype

The “cuttlefish” prototype

The cuttlefish gave us a good first impression of how we were going to proceed, both on the hardware and software sides. One realization was that, as long as we were using our own custom software to synthesize the sounds (see my Pythagoras repo), there was no reason for us to bother with the MIDI protocol. We could just write small, byte-sized messages to the serial port, and then trigger callbacks in the software every time a byte is read. Another realization was that we needed to debounce the signal from the switches – otherwise, each key press would result in several erratically-timed notes being played. But most importantly, we realized that this was totally going to work maybe!

The next step was to move these concepts over to the circular table design. So we cut a circle (41″ in diameter) out of a piece of 1/2″ plywood, and made 24 cuts along radii from the outside. The length of the cuts was determined by experimenting with another single-key prototype to achieve a good action with the wood’s flexibility.

Testing out the flexibility of the first cuts in the top.

Testing out the flexibility of the first cuts in the top.

The next challenge was mounting the switches underneath the keys. We knew we were going to need a mechanism which allowed for adjustment of the switch height, because each key had a different flex according to its grain direction (the joys of working with wood). But the switches we had were very small and very simple (and very cheap) – they provided no easy way to mount them at all. So we ended up coming up with a system where the switch is clamped, facing down, between some blocks of wood on the underside of the keys. Beneath the switch, we thread a 1/4″ hex bolt through an angle bracket mounted on the spacer block. By turning the bolt, we could raise or lower the sensitivity of each key individually.

All 24 switch mechanisms, mounted on the underside.

All 24 switch mechanisms, mounted on the underside.


A close-up of a few of the switch mechanisms.

A close-up of a few of the switch mechanisms.

Once all the switches were on, we wired them into the Arduino and tested the action. We noticed that sometimes, depressing a key would warp the entire top in a way that pressed several other keys simultaneously. To make the whole structure more rigid, and also in anticipation of the “safety bumpers” we were going to want to put under the keys, we mounted another plywood disk, about 3 feet in diameter, on the bottom of the wooden spacer blocks, preventing their relative movement. This helped immensely in keeping the top from flexing like a big saddle every time a key was pressed.

We had also picked up some potentiometers and a rotary selector switch from JB Saunders, which we wanted to mount on the top to control some parameters of the programs we were running. So we mounted the rotary switch right in the middle, as a kind of mode selector, and then mounted the 3 pots symmetrically around that.

With knobs and bottom layer installed.

With knobs and bottom layer installed.

The neatly organized guts of the Cyclophone.

The neatly organized guts of the Cyclophone.

At this point, the Cyclophone was nearly complete – all that was left was to pretty it up. We thought about just painting it a solid color, but we realized that with such a large instrument, it’s actually difficult to keep track of the keys when they all look the same – a unique design would be much better. We had originally planned to have an artist friend paint the top, but with just a week left before Apogaea, and summer jobs keeping people busy, scheduling conflicts made that impossible. And so we were left – a physicist and a software engineer – with the task of coming up with an artistic design for the top. We ended up using the only graphic design tools we were comfortable with – polar equations – to come up with a sort of rosette design for the top.

Rosette made from 6 logarithmic spirals.

Rosette made from 6 logarithmic spirals.

Close-up of paint job.

Close-up of paint job.

The paint job took about 3 days, during which we applied 3 layers by hand. After that, we built a base for the thing, so that it sat about 12 inches high, good for playing while seated on the floor. Finally, Dan Julio donated an RGB LED strip and driver to illuminate the table from below.

Shown with LED strip illuminated.

Shown with LED strip illuminated.

On its base, painted and ready for Apogaea!

On its base, painted and ready for Apogaea!

At Apogaea, the Cyclophone took its place in the center of the Soundpuddle. We had it running off Ben’s laptop, with 5 modes to choose from, via the rotary selector:

  1. Chromatic sine waves (Soundpuddle mode)
  2. Tabla samples + koto, chimes, and guitar (all pentatonic)
  3. Half piano, half guitar (harmonic minor scale)
  4. FM synthesizer (major scale, parameters tunable by knobs)
  5. Drum circle
The Cyclophone in the Soundpuddle at Apogaea.

The Cyclophone in the Soundpuddle at Apogaea.

Here’s a video of the Cyclophone fulfilling its destiny at Apogaea:

We had a lot of fun working on this project, and I expect it won’t be the last USB controller we build (next step, velocity sensitivity!). It was also great being part of the Soundpuddle project – many thanks to John English and the entire Soundpuddle crew for making it all possible.

Nearly all of the code we used in this project is available in my Github repo. If you have specific questions about the construction of the Cyclophone, feel free to contact me (Chris Chronopoulos) or Ben Burdette.