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[apophis]

I built some chimes out of copper tubes... and they sound pretty good! This is a fun little project. Here is what it looks like:

 

 

The finished product is a bit large. The overall dimensions are about 15" wide, 8" tall, and 3" deep. I planned my cab layout to include these chimes, so it works for me. It can be mounted to the floor or wall.

 

Here is a link to a video so you can hear them.

 

The tube chimes are tuned to the musical notes C5, F5. and A5. The chimes themselves are made from 1/2" copper tubes (L-type). The coils are being driven by a 24V source, but I think I should kick it up to 48V to boost the volume. I'll post a video once I do that.

 

I learned a lot about tubular chimes from this web site which I highly recommend reading.

 

BUILDING THE CHIMES

 

If you want to build your own, below are a few lessons I learned that may help you out.

 

1) Start by cutting and tuning the highest note, i.e. the shortest tube. If you make a mistake and need to throw out the tube, then less material is lost. Also, once you've tuned one note, you can accurately estimate the length of the other tubes. Here is are the final lengths of my tubes. If you want these notes, I'd recommend cutting your tubes AT LEAST 1/8" longer than the values listed below. You can always remove material. but can never put it back!

     A5: 11-3/16"

     F5:  12-3/16"

     C5:  14-1/8"

 

2) Do the tuning BEFORE drilling holes. When you drill holes in the tube, they will slightly detune the note such that you will have to sand down the ends a little bit to bring it back in tune. 

 

3) Drill the holes a distance from each free end that equals 22% of the overall tube length. You may want to add about 1/16" of length to that 22% distance rule because you will need to sand the ends down slightly after drilling the holes. I used #8 screws, so I drilled holes just large enough for those to freely pass through. 

 

4) Use the natural extrusion lines that run axially down the tube to align the drill holes. You will also want to set up some kind of jig to ensure the thru hole penetrates the tube diametrically. I used a slotted board to line up the drill bit with the slot first, then placed the tube in the slot before drilling. This seemed to work well.

 

5) You definitely need to mount the tubes to the board using vibration mounts. Here is a link to the mounts I used. Without these mounts the tubes won't ring at all.

 

6) Layout the tubes and coils before mounting to the board. This is the best layout I found.

 

7) Use some T-nuts to mount the tubes to the board. Here is picture of the T-nuts installed:

 

8) When mounting the coils, it seems best to have them strike the tubes at a 90 degree angle from the vibration mount axes. This is different than typical pinball chimes, but its what I found sounds best. Also notice that I had to mount the coils on a second 3/4" plywood board so they were at the right height relative to the tubes.

 

9) You will need to add some wood below the coils to catch the plunger. I mounted these using a dowel and some glue. Leave some room below the plunger to include a felt pad to dampen the impact between the coil plunger and wood block.

 

10) I used some 1/2" plastic cable clamps to hold the coils. These worked great.

 

11) Don't forget to include diodes on the coils.

 

Good luck!