Picture of Turn a Tennis Racket into a 3-stringed guitar
Everyboy at some point has picked up a tennis racket and pretended to play it like a guitar. It's human nature. Well now you can do that but have it actually make noises too!

I first made this instrument a few years ago and have been meaning to put up a guide ever since. This won't be a step-by-step 'do this exactly' type instructable. I'm going to show you how I did it, highlight the important parts and let you realise you could have done this all by yourself if you really wanted to.

You Will Need (roughly):

Wooden Tennis Racket

A Piezo Transducer (http://www.maplin.co.uk/piezo-transducers-3202)

A 1/4” Mono Chassis Socket (http://www.maplin.co.uk/1-4-mono-chassis-socket-1252)

3 Tuning Pins (I got mine here: http://windworld.com/products-page/hardware-for-acoustic/zither-tuning-pins/ although if you want to go proper DIY, check out my post on DIY tuning pins here: http://www.vulpestruments.com/2013/02/a-note-on-diy-tuning-pegs.html)

Some scrap wood

A few bolts

Some L-Brackets

Step 1: How to make a Contact Mic

Picture of How to make a Contact Mic
First up, solder the Piezo to the mono socket. Congratulations! You've just made a contact mic.

With this simple little thing you can turn just about anything into a plug-in-able noise making monster.

The piezo works by taking small vibrations and converting that into a small AC-Current via crystals and magic. This, when amplified, makes loud noises.

A little tip for this, I often find the soldering on the white part of the piezo to be quite fragile. I usually place a bit of cellotape ontop of it to help strengthen it. It seems to work!

I also noticed your instructable about the DIY Pickup. What is the difference between these two pickups? What pickup would you recommend for what instrument?

jetpower2 years ago
You've given me a reason to take my old Jack Kramer out of its brace!

You mention that you have fret ideas, so I'll watch and wait. A number of historic African and Indian instruments might also provide insight there.

You use the Bonnie Raitt bird-finger placement for your slide! Speaking of which, an automotive spark plug wrench makes a great slide, with its weight adding a lot of sustain. Beer bottles are also known for their value as ad hoc slides).

As you show, the piezo pickup picks up everything. You might consider adding a resonator for a future build - the challenge will be to make one in the shape of the racquet head, and/or to remove the strings and find a way to suspend the resonator inside the head. Alternatively, you could stretch a skin over the head and place the bridge on it (banjo-style), which would also increase the acoustic volume. Of course, that would be getting pretty fancy.

Abunda's idea makes a lot of sense for a couple of reasons:

1) The racquet strings ("cords") are already in tension by design. Removing a few (and retaining the stretch of the remainder - you can tie them off) to make way for threading the metal strings would improve sustain and enable more stable and higher tuning - which would also enable locating a "sweet spot" where the racquet string tuning would be most sympathetic with the metal strings.

2) Using gut strings would present a true harmonic convergence (!) of the tennis and guitar uses: Premiere racquet strings, as well as classical guitar strings, are made from (generally cow, not cat) gut. Buy them - you could make gut strings, but that's a whole 'nother 'structable...

Good job!
A kid's(and a few grownups') dream to reality. You get my vote!
I posted the above comment from a mobile device and it seems to have gotten duplicated 6 times! Sorry for the spam...
can you play it without the amp??
gare84212 years ago
Cool project.

One thing that I tried to help increase volume of the pickup, I made the "bridge" out of wood (In place of the 3 metal L brackets. And sandwiched the piezo between the spatula "tailpiece" and the "bridge". Strings hold the bridge down and squeeze the piezo tight. Very loud.
offtandiscord (author)  gare84212 years ago
Yup, there's hundreds of different ways you can do this project!

Placing the piexo in various parts of the construction will also lead to different sounds being made. I'm guessing if you placed it away from the bridge it would be a lot quieter but maybe pick up different frequencies...
abunda2 years ago
¡Nice Nice idea! Next natural evolution step is to use cord's holes (so strings can be tensed by the wood) and maybe place the piezo in a violin-like bridge?
rags_angel2 years ago
So cool!!
What did you use for the strings
offtandiscord (author)  eaglescout132 years ago
I used the wire from the core of a washing line...

I make a lot of prototype instruments so had to find a good, cheap source for wire to use. If you take off the plastic layer on most washing line there is a core of twisted wires that work quite well!

For this though, you can use any string you want. the mic picks up vibrations so any string would work.
kondzio292 years ago
Nice! I'll vote on you in Musical instruments contest ;)

You're one of the persons on instructables who made an instrument and play on it later.
Most of ppl here just make an instrument and cant play on it- you do.

mikeasaurus2 years ago
This is awesome!
I can't even count how many times I've "played" a tennis racket "guitar" (just last week being one of them!). It is so cool that you actually can now!
Kiteman2 years ago
I love the sounds that homemade instruments make!