Hooking the encoder up is easy, I meant finding a way to make it work with Objects In Space. It's a lot like a pair of switches switch. You provide power and ground, and then hook its two output up to a couple of inputs.
The complicated explanation for how it works is to say it produces two square wave outputs that are 90 degree out of phase when rotated. Basically it's like reading two switches, except in order to determine direction of rotation, you have to remember the previous state of switches. The output sequence for rotation in one direction is as follows 00 01 11 10, and reversed for the other direction.
The only differences between this one, and the much more common, smaller, cheaper rotary encoders, is 100 pulses a rotation instead of 20, the small ones are also usually a push switch as well, and it comes with the knob permanently attached rather than being just a splined shaft.
They are 500uA 650ohm VU meters with a 12v 55mA bulb backlight, or at least, that's what some sellers list them as. Accurate specifications tends to be lacking from a lot of listings. I've pulled the specs by polling a lot of different listings for the same item. Mostly the are just listed as "Warm Back Light Panel VU Meter" with a few other words thrown in, and little to no specs.
Paint would not be my first choice, especially since I lack in artistic skills, it's too opaque to be used in something that is back-lit and the thickness of the paint could interfere with the movement of the needle.
I haven't soldered them up and tested them yet, but assuming I have chosen my series resistor correctly, it shouldn't be to hard the get them going.
It took me a while to figure out how to open them at first, I couldn't see a seam. After a few moments of panic, I realised the seam is right behind the mounting flange. It just pulls apart. Replacing the display is going to be tricky, since it's back-lit, I can't just stick a new face over the existing one as it will show through. What I will probably do is print a new face and glue it to a piece or two of transparency for stiffness.
Now that I think about it, I may be able to use to original plastic piece by carefully sanding it to remove the old markings, and just gluing a new face on top.
Next time you may want to consider checking automotive stores (like autobarn and such), since that's the market most of these are manufactured for (hence the 12 / 24V rating on most of them). Price was my determining factor, so most of it came from various seller, based in china, on several online auction / sale sites. Mostly ebay. I could probably have bought most of the switches / buttons from a single seller, possibly even one based in Austraila, but I was looking to minimize cost not delivery time.
They look good, but the LED back-light is probably not going to work out (I haven't tested it yet). I may end up trying these, which were my first "modempunk" choice. I didn't order them because they are twice the price, and I'm not certain that converting them to a 5V independently switched LED is going to be particularly feasible.
I do, it's @Uninterested42, though I mainly use it to complain about things, since sadly that seems to be the fastest way to get issues resolved these days.