Control Box/Electronics Housing
I found a pretty basic plastic box for electronics projects on Amazon. All the electronic components fit into into (miraculously).
Fitting everything inside was a big challenge. I didn't want to use a box too large and bulky. Keeping track of all the wiring became a huge headache so I decided to get some simple Molex connectors with pin and socket contacts that I crimped onto the wires. This allowed me to have easy connections for all the wiring that goes from components attached to the lid of the box and components attached to the bottom of the box. But before I could do all that I had to create a wiring diagram just to keep track of which wires go where.
View of the underside of the control box lid:
View of the exterior of the control box:
View of the inside:
Mounted to frame with L brackets I bent to the desired angle:
The whole system is essentially finished at this point. I wanted to try and find a way to reduce or muffle the sound of the motor. I built a box around it out of sound proofing foam panels and really thin project plywood. It really only reduced the sound about 20%. So I'll just have to live with the amount of sound it produces. I don't really know what else I could do to reduce it even more.
Project complete! I made video to demonstrate using the motor and everything it can do. Enjoy!
I did a good bit of research on motors and how to choose one that will fit my needs. I ended up buying a 12V DC motor with a gearbox with a max speed of 146 RPM. I also had to find one that could had higher torque ratings than most typical DC motors for hobby projects. The gearbox allows the motor to spin a much lower speeds than with just the motor by itself. The motor I bought also came with an encoder built into it. The encoder is essentially a sensor that reads the speed of the motor. This will come in handy later on. The biggest downside of a DC motor with gearbox is the noise the motor makes. It's a little too loud for what I wanted, but I'm going to be doing some research on how to muffle the sound of the motor.
I built a simple housing unit or mount for the motor. This secures the motor in place with no room to wiggle while it's turning. This unit will be attached to the vibraphone frame. The motor shaft is braced in a plastic rod exactly like the fan rods are held by those plastic rods seen in the previous post. This reduces stress on the shaft and allows the motor run more efficiently because there's less resistance. Not shown in these photos below are 2 pipe clamps wrapped in bicycle inner tube pieces (shown further down). The inner tube pieces acted as filler to eliminate excess space between the top of the motor and the clamps. It's also gives it a very firm grip on the motor, making sure it won't move while running.
Attached to the shaft is the same wheel I used for the rods that spin the fans. I decided on using polyurethane tubing as the belt that pulls the rods. This tubing has the same exact radius as the outer groove on the wheels that will pull it so it should be pretty efficient.
I had to cut the tubing to the approximate length I estimated I would need and then fuse the ends together by melting them with a soldering iron and then firmly holding the ends together. I trimmed off the excess material at the fusing location with an exacto knife.
I made a pretty simple circuit to control the motor with the Arduino and a potentiometer (It's pretty rough and hideous looking right now). I won't go into how all that works in great detail. But essentially the Arduino uses PWM (Pulse Width Modulation) to vary the speed of the motor. The PWM signal is sent to a MOSFET transistor which then sends the motor a certain voltage for the desired speed. For just controlling the speed of the motor, I don't need an Arduino or any type of micro-controller to do that. But later on I'm going to be using the Arduino to program sequences for the motor to perform hands free. These sequences could be gradually increasing or decreasing speed over a certain amount of time or performing a defined set of speeds and operations based on exact time durations.
After setting up the Arduino, mounting the motor to the frame, and installing the belt the whole system was ready to be tested for the first time. I made a video to show the whole system and to test out using the audio editing program Audacity to help eliminate the sound of the motor after recording. The motor is simply too loud to record with without any type of editing to the audio. This whole fan and motor system so far has turned out way better than I originally anticipated. To my surprise the fans can spin continuously without scraping on the inside edges of the resonators. I was pretty fearful that would be a problem.
My next steps are to experiment with eliminating motor noise and also designing a whole electronics control box that will have an easy to use power switch, speed dial, 3 preset buttons, and even an LCD screen to display the RPM and the titles to any preset sequence I might be using at the time.
After a year and a half, I finally got around to fully completing the vibraphone... almost. I've started building the fan and motor system, which is what produces that vibrato effect you sometimes hear. When I originally built the vibraphone I decided to not include that feature just because it's really complicated and would add much more time on top of the already lengthy 10 month process. I've had some free time lately so I figured I'd get my hands dirty with this.
When I originally built the resonators I created notches on the tops of them so that I could one day come back and add the rod and fans like I'm doing now. The vibrato effect works by essentially opening and closing the resonators. There is a long metal rod that runs along the center line of the tops of the resonators. At each resonator tube there are metal discs attached to the rod. The entire rod spins via a motor pulling a belt. This creates a constant opening and closing of the tops of the resonators.
I started this portion with the rods. I found a metal supply website that had the exact type and dimension I wanted: 1/4" diameter hollow stainless steel rod. This type is going to be much smoother and straighter than rods you can buy at Lowes or Home Depot. The rod rests inside holes drilled through these plastic rods attach perpendicularly to the resonator frame. These lift the bar up so it doesn't actually touch the resonators anywhere. And fewer points of contact means less friction.
The next step is to make the discs or fans. I used the thinnest aluminum sheet metal I could find at Lowes. I cut them them out into a sort of elongated circle shape a little smaller than the inner diameter of the resonators.
I didn't cut them into perfect circles because I formed their shape by bending them around the rod so there's a hump in the middle. So after that shape is formed the overall shape looking down on the disc is a perfect circle.
Then I painted them black... of course. At the high ends of these rods I attached sliding door wheels that will allow the belt to turn the rod.
I used a 2 part 6 minute epoxy to glue the discs and wheels to the rods. The discs were glued alternating direction every resonator to make the whole rod balanced and not weighted more to one direction.
The next thing I need to do is buy a motor and build a housing that it will sit in and attach another wheel to it that will pull the belt. I'm also going to be experimenting with controlling the motor with an Arduino probably. This will allow me to control the fans in ways that you can't do on any other vibraphone, at least that I know of. I made a video to test how the effect of the fans sounds. I simply pulled on a string attached to one of the wheels on the rod under the natural keys. Stay tuned for the next post on the motor. No clue how long that will take though.
I finally got a microphone to record with. I'm an avid listener of Icelandic composer Olafur Arnalds. His music mostly features piano, strings, and sometimes electronics and is often very minimalist. I got a hold of some of his sheet music for free on his website! I discovered that much of his music sounds really fantastic played on vibraphone. The simplicity and tempos of his music makes a perfect transcription to vibraphone. I decided to record every single part to his piece called Near Light on my vibraphone. I also bought a couple of string bass bows on eBay to play the string parts. This is pretty much my first attempt at music recording and video editing. I learned a ton of things about both topics just from getting to try things out on my own. I'm pretty happy with the result. After 10 months of completing the vibraphone and moving it 900 miles, it's still sounding and functioning great. Feel free to leave a comment on the YouTube page.
I officially finished building the vibraphone on February 1, 2016. Nine months since I started, or at least since I picked it back up in May 2015. I had no idea what I was getting into when I started. I wish I logged all the hours I put into this, but there's too many to even begin to make a guess. It's a very rewarding feeling to just look back on something you made yourself. By no means is it perfect because there were many mistakes along the way, but I feel very satisfied with it nonetheless. I'll be uploading videos later to show how everything sounds.
After completion, the grand total cost for the vibraphone is $949.10, which includes the cost of tools I had to buy. If you subtract the cost of tools, the cost of materials to build the vibraphone is $647.99. This is pretty amazing because a brand new, manufactured vibraphone (Adams, Yamaha) will cost anywhere from $3,500 - $8,000. If you're interested, I uploaded a spreadsheet showing the cost of each item and all the subtotals.
I would like to thank Jim McCarthy who runs the website www.makeamarimba.com. There you can purchase very detailed instruction manuals on how to build your own marimba, vibraphone, or glockenspiel. I based my design partly on his plans and partly on my own. But they were a HUGE help to have. I would also like to thank my parents for allowing me to take up half the garage at their house even after I moved out. Also for all the tools my dad had on hand that I didn't have to buy.
Thanks for reading my blog. If you have any questions or comments please leave a comment or email me at conn210@gmail.com
But anyways, here's some pictures. (I have no training in photography whatsoever.)
