How to make a DJ turntable from old computer parts.
Some time ago I have discovered a piece of software that is using the mouse movement (up-down / left-right) to make scratch-alike effects on a virtual turntable, the way the DJs are doing it in clubs. It is the TerminatorX software, developed by Alexander Koenig (http://terminatorx.org/).
But using the mouse is not even close to a real turntable. So here is a way to make from an old mouse and other parts a more realistic turntable.
I have tried several models made from recycled computer parts, and I will present you all of them here.
Step 1: Preliminary information
The first think you should know is that TerminatorX runs on Linux. There is no windows version yet. I have tried it in Ubuntu and worked fine. It is in the repositories, so it is very easy to install.
The software is designed to use the movement of the mouse on the X and Y axes and execute a custom chosen action. Usually I use one ax for scratching and the other one for volume control. Also each of the three buttons has a specific function. Left for grab (and scratch), middle for mute the current virtual turntable and right button for change to next turntable.
The turntable consists of 3 parts:
-a mouse with ball and 3 buttons (NOT an optic one)
-a spinning plate
-a table or support for them
Functioning: The spinning plate rests with one edge on the mouse’s rollers and they will spin together. When you spin the plate the mouse will detect it and will send the information to the software.
Materials that I used: one old (but functioning) mouse with 3 buttons and ball, an old CD-ROM, an old hard drive, an old keyboard, a CD, a floppy disk and a vinyl record. For putting the parts together I used double sided adhesive strips and magnets.
Step 2: Prepare the mouse
We need free access to the mouse’s rollers (the two axes that are in contact with the ball).
Warning: this will make your mouse unusable.
Take out the ball and open the mouse. Cut all the plastic parts that are higher than the rollers, and optionally cut all the unnecessary plastic from the case around the electronics. If you cut too much, the electronics will not stay in place any more and we don’t want this to happen.
Keep the plastic part where the screw was housed and the mouse wheel for later.
Now you can spin the rollers and press the buttons from the electronic board with your fingers. Make this to assure that the mouse is still functional.
At the end add a double sided adhesive strip to the bottom of the muse so you can stick it in place when you finish the turntable.
Step 3: Add buttons
As an optional step we can add some buttons to the mouse.
Use the wheel and the screw housing from previous step to make a knob to control the second roller. Find the best position and glue the plastic parts together. The wheel will remain free and in contact with the roller. This is ideal for volume control.
Use 3 keys from the old keyboard to make the mouse buttons easier to pres. I used some scotch tape but the double sided adhesive strip would have done the job much better because it can be applied directly between the mouse button and the new key. The middle button was the easiest to put because the legs fitted into the plastic piece of the mouse’s button.
Important: make sure that the plastic legs of the keys press exactly on the red part of the mouse buttons.
Step 4: Spinning plate from CD-ROM
The best spinning plate, in my opinion, is a CD. And an "easy to find" support for it is the motor from an old CD-ROM. It is designed to hold a CD in place so we will use it.
All CD-ROMs differ from each other so don’t expect to be exactly like in the picture.
Unscrew all the screws you can find and open the case. Locate the motor and free it from its screws. Also keep the round cap that covers the motor. It is usually on the metal case or an additional metal plate on top of the motor. It will fix magnetically to the motor holding the CD in place.
Also notice that near the lens is located a pair of powerful magnets. Use a screwdriver to pop them out and keep them for later. We will use them to fix the motor to the board.
Step 5: Spinning plate from hard drive
The same like the CD-ROM, any hard drive contains a spinning motor. The good part is that it already has the plate attached to it, but the bad part is that it is harder to hack. You will need a screwdriver with a six pointed star shape which is not a common item.
Take care at the hidden screws. The hard drives are full of them. Take out all the electronics and keep only the metal case (if you can fit the mouse inside) and the spinning motor with the hard drives plates.
Step 6: Vinyl plate
A vinyl plate would be more close to reality, but it is hard to find a spinning motor to attach it to. Luckily I was able to take out the plate from the motor of a hard drive, and attach the vinyl disc instead.
Step 7: Turntable from CD-ROM case
Now is the moment of assembly.
Use a metal plate from the CD-ROM case as a table. Put the mouse and the CD on it to find the best position. Stick the mouse on the plate with adhesive band (or any other type of glue). Fix the Spinning motor with the two magnets on the plate. Now add the CD and the cap to hold the CD. Make sure that the edge of the CD is resting on the mouse’s roller.
And there you have the first turntable.
Plug it to a computer and play with it.
Instead of the CD you can also use the hard drive plate.
Step 8: Turntable from keyboard
The TerminatorX software can use only the mouse for scratching. But there are also a couple of more functional keys on the keyboard that can enhance your scratching experience. Normally you can use your existing keyboard, but why not use a second one?
From an old keyboard I took out all the unnecessary keys, leaving only the ones compatible with the software. For example the F1 to F12 are the numbers of the virtual turntables (maximum 12) and the Tabb switches to the next one. Note that you can scratch only on one turntable at a given time. The rest of the buttons I will explain to you later.
Now, in the free space on the keyboard you can attach the mouse part and the spinning plate. You will need to plug both the keyboard and the mouse into the computer to use this table, but it is a more dedicated device. You can also use all sort of decorations on it (mine didn’t needed any because of the cool contrast of the white keys and the black plastic background).
Step 9: Turntable from computer case
Do you need a bigger table for the vinyl plate? An old computer case cover will just do it.
Use the vinyl plate mounted on the hard drive motor and 3 or 4 mice to have multiple support points like in the picture.
Again use glue or tape to stabilize the mice on the metal surface and magnets for the plate.
You can connect it to 3 or 4 computers in the same time ;) but it is unlikely to be more useful.
Step 10: Turntable from hard drive
This is a more tricky one. My first idea was to take a hard drive with multiple disc plates, to take out the bottom plates, to leave only the top plate in place and to fit the mouse parts into the hard drive case with the roller under the plate's edge. Failed!
Instead, put the mouse parts on top of the hard drive case (like in the photo) fixing it in place with adhesive strips. Use some magnets to fix a second hard drive plate and motor on top of the first one and its ready.
This version is more shiny and beautiful, but it is a little unstable.
Step 11: Turntable from floppy disk
Now this is the smallest turntable that I have made.
Open one floppy disk in half and take the metal disc from the middle. Pay attention how the two plastic parts are bound together.
Take another floppy disk and open it only on one side (the one where you can see the thin plastic disc from inside) and insert there the metal disc from the previously obtained. (see the picture for more details)
Place the mouse parts in pace and fix with magnets the hard drive plate with motor on the metal disc you have just inserted.
Step 12: How to play
In order to play with it open the TerminatorX. There is a virtual turntable opened by default.
Press Ctrl+A to add a second turntable. Each turntable has as button named Mouse. When you press it you can choose the actions for the X and Y axes. The X ax is by default for scratching
but The Y is set to Lowpass. Put it to Volume.
Drag and drop two audio files on the two virtual turntables. Press the Power button. Now the two audio files will start to play both in the same time.
There is no crossfader between the two turntables, but you can mute one or another any time you want.
Now press the Mouse Grab button.
Attention: in this moment your mouse will no longer act as an usual mouse. All the control is transferred to the terminatorX. To exit the Mouse mode just press Esc.
To scratch, press left mouse button and move it left and right. If you press middle button you will mute the current turntable. With the right button you can jump to the other turntable in order to scratch with that one.
Extra functional buttons are available from the keyboard:
w – mutes the turntable and allows you to navigate fast to any point in the track (needle-drop stile recueing)
f – same as w but without to mute it
m – mute the track while pressed
alt – mute the track with a short press and regain the sound while presed
ctrl – regain sound after alt was presed
tab – next turntable
space – scratch
back space – go to the beginning of the track and stop
return – restart the track
F1-F12 – Turntables 1 to 12
esc – exit mouse mode
For more details visit the http://terminatorx.org/ website.