Mighty theatre organ, now in your living room.
I provide set of 86 different tabs together with simple mechanism that allows you to switch ranks on your organ. Mostly theatre organ stops and effects were prioritized.
These tabs dont use electromagnets to move up and down after pressing pistons but they can be used to manually control virtual theatre organs such as MidiTizer, Jorgan or Hauptwerk.
I have also designed a circuit board that scans matrix of switches and sends midi signal, so check my web page if you are interested (sp6gk.com).
Each tab consists of four parts:
- Mount is stationary element that holds switch, at the top you should glue a conductive material.
- Switch moves up and down, makes contact pushing the glued wire to the top part of the mount.
Switch is a element that is main part of lever, it is mounted between two holes in mount and puts friction against mount when it is switched up or down.
- Tab (ex Tibia 8) is tongue like end part that is actually visible by the organist.
- Tab Magnet upgrade, this part is optional but highly recommended. When mount wears off due to friction the magnet holds the switch down and provides some threshold so that it does not go down on its own.
How to assemble the tabs:
- Use file on the inner edges of mount or remodel it according to how accurate your printer can print. I recommend sticking to filing small portion of the inner edges where switch rotates since you can fast print a lot of mounts with 0.28 layer and then make the row smoother, going other way (adding friction) is more difficult.
- Cut the upper horizontal bridge in one point, you can use it further to tighten the mount if it spreads on sides to much when switch is moving (by gluing the bridge back).
- Put the desired tab on a switch, it should slide very tightly. You can hold the switch vertical with tab up and gently hit the top of the tab with screw driver hand grip.
At this step you should also use sand paper to smooth the tab and spray paint it.
- Put switch with tab into the mount, first you can slide it in at an angle, then when one point of switch inside the hole of the mount you should push on the other side so that it clicks in.
- At this point you can glue the magnet upgrade to the bottom of the switch with magnet pointing down. I recommend gluing the magnet to the upgrade part before.
Making contacts
There are few ways to make the tab actually work as a switch.
First you can use reed switch, since you probably want to use magnet anyway.
The way that I have used is to use brass sheet and wire:
Cut something conductive and thin (i use brass to which i can solder) into a 10x25mm strips and glue them on the upper side of the row on which switch moves up and down.
Then remove isolation from a cable that has copper strands, about 25 mm for each switch. This wire is glued to the top of the switch and par that extrudes into a row makes contact with brass strip, the other end goes behind the switch.
Final chord
The switch upgrade magnet part is designed for a cylindrical neodymium magnet, 4 mm in diameter and 3 mm in height. I have added this improvement since normally the friction would wear out the row where the switch slides and more often used tabs could just slide down under their own weight. I have been using those tabs for more than half a year and they still work great.
In the future I might try to make an actual SAM using a servo motor.
Enjoy,
SP6GK
SP6GK
