Introduction: A Kalim'beer - the Kalimba From a 5L Beer Drum
Since a midle term while I am interested in DIY music instruments.
And sometimes you can have a kind of positive surprise.
This happened to me when building this instrument.
Actually I wanted to build a tank drum from an empty beer drum I found nearby my place.
I tried already with other systems but I thought this one must be easier for that purpose.
The walls of the drum are quite thin allowing a quick and dirty work and its is made of steel to maintain a pressurized liquid so must be quite springy and stiff material.
(A lot of different tank drums do exist: DIY, homemade or commercially availlable
I can cite the very good propane tank drum instructables from Hermes
following the original instructions from Dennis Havlena,
Unfortunatelly I assumed something and what I obtained is something else.
No tank drum was built but instead another instrument as cool as what I wanted was obtained.
So the birth of the Kalimbeer takes its origin in a failed tank drum design.
Long life to him :)
Just a mention on the contents of this instructable-->attribution non commercial sharealike.
You can re-use my texts and my pictures, modify or whatever, if you do so please cite the author, my work or even better put a link to this instructable. I would appreciate your cooperation :) In addition if you have any comment or improvement that you would like to share with me please do it.
I would like to make a gallery of Kalim'beers at the end of this instructable, If you build one, send me a picture :)
safety issue or important notice
EDIT: I changed slightly the name of the instruments - I fount it very cool, but this name is already taken by a country punk music band (or musician... I do not read Czech) from Czech Republic. I am sorry for him/them, I was so proud of the name I found out :) I just modified the name slightly for that reason.
Step 1: Inventory
-A rotary tool for model building with circular saw
-Protection equipment (kevlar gloves and safety googles AND ear protection)
-A 5L beer drum made of steel (if no mention about the material is written, then take a magnet, if it sticks to it then this is right)
-a stiff screw driver
-a multitool claw
- a drill with max 1cm diameter bits for metal
- a marker
The assistance / supervision of an adult is necessary if you are below 18: Danger of serious injuries whilst metal cutting procedures
Step 2: Free the Drum From the Various Plastic Parts and Draw Shapes on It
The beer drum comes with a upper plastic part that serves at regulating the air pressure above the liquid (when still full of beer)
The lower plastic part is basically a tap that you need to pull and turn to enable the glasses to be filled.
-And by the way this is very interesting how it is made-
Both plastic parts must be removed.
I did it with pure muscle force and patience using a screw driver and a multitool claw. you can see the impacts around the two holes.
You can alternatively drill the plastic parts off, this may help!
Once the beer drum is unloaded from its unwished plastic pieces, you can go for the design step.
Draw a quite large piece with a wide basis (this is important, Think that you can always cut more if necessary, but if you already have cut too much, this will lead to a non working tongue, and this is bad)
The shape I did is a wide flat arrow like that => more or less.
I used a file to scratch the surface, but you a marker is more appropriate.
This is easier for the next step when using the rotary tool.
Step 3: Cutting the First Shape and Testing It
The first shape is very important, because it will gives you the information about how the other shapes need to be drawn. The design of the tongue is also a question of the material itself.
I invite people to read the book
Musical Instrument Design, 1996, Sharp Press from Mister Bart Hopkins.
a very important ressource to whom wants to build his own instrument.
A stiff metal sheet will answer very differently to an imposed displacement as a soft metal sheet.
************The shapes must be drawn on the same half side as the holes left by the plastic tap**********
You cut your first tongue along the shape using the rotary tool
(Be careful this is a nasty tool, kevlar gloves and safety googles AND ears protection are mandatory, if you have something to block the drum it will be benefitial as well)
You obtain an very flat arrow shape right? good then you can plug the tip of it.
A) you plugged and the metal sheet vibrates very shortly with a very low amplitude (that means the metal sheet is quite stiff, which is quite good). You need to increase the length of the arrow tenth an inch by tenth an inch with the aid of the rotary tool. At each step you will try the response of the tongue. You can stop when the metal sheet vibrates longer but still with low amplitude. The tongue must have a clear elastic springy behaviour.
B) you plugged and the metal sheet vibrates with large amplitude and slowly. Sounds very little and in lower range and does not show a nice elastic behaviour, it is much too soft.You need to cut the tip of the arrow tenth an inch by tenth an inch with the aid of a large scissor.
you stop when the metal tongue vibrates shorter but with a higher amplitude. The tongue must act as a spring and at this stage must a have a satisfying elastic/vibrating behaviour.
If you have too much increased the length (case A), do not worry apply B until you obtain satisfaction
This important instruction is largely influenced by the work of Bart Hopkins.
Once you obtain the right shape, you need to repeat the same shape at various size by just scaling it.
The best way if you can, is to take a picture and print various models scales. I did it by feeling it works not so bad.
Step 4: Cutting the Tongues Following the Previous Results and Finishing the Kalim'beer
Once you have obtained a satisfying basic shape, you reproduce it at different scales 5 or 6 further tongues. Place those tomgues on the same half side as the hole left by the plastic tap piece.
Now it is time to cut the drum further - following the same safety instruction as mentionned previously. This is dangerous.-
Check each tongue if each is responding in a satisfying manner.
If not you need to improve the tongue by reducing the length (cutting the tip side) or by increasing the length as mentionned previously for the testing shape.
Once the sound is Ok, you need to make the tongues smooth and safe for playing.
Sanding off the edges with the files will remove any sharps metal needles.
you can then bend the tip of the arrows for an easier music play.
Place the instrument with the tongues oriented in your direction like playing with a kalimba
Bonus: Add water in the drum and close the side hole with cork for example. small movements of the drums will affect the sounds like with a waterphone. I had fun trying this. I made a short video footage, sorry for the camera moves :-) for those who can play it.
Its sounds is a litlle bit cosmic isn't it?
I wish you a good time with your kalim'beer! and share with me a picture!