Rotary encoder fix for the Kawai K5000
Having an unreliable / faulty 'value' rotary encoder on the K5000 can be real pain, especially if the values skip, jump or even go backwards!
The bad news is that Kawai no longer offers spare parts or technical support (in the UK at least, I doubt they're much help elsewhere). Third party repairs should be possible but are likely to cost quite a bit of money and you may need to post or take the synth to someone hundreds of miles away..
The good new is that in most cases IT'S AN EASY FIX !
Here's what you need:
1 - Phillips screwdriver
2- Small pliers
3 - Small flat screwdriver, tweezers or small tool
4 - Cleaning cloth (something like a small spectacle cleaning microfibre cloth should do)
5 - Contact cleaner like Deoxit, Servisol, Teslanol, etc (Isopropyl Alcohol should also do the trick, although contact cleaners can provide lubrication so they may be best in the long run)
Before you start, disconnect all cables and power from the synth. The tutorial below shows what to do, but you should not connect the synth to the mains until you've completed the steps below and reassemble all the parts. There's 240v going directly into the synth, and the cables are exposed when opening the bottom plate so you don't want to be electrocuting yourself. In any event, this tutorial is for guidance only so anything you do is at your own risk!
Step 1
You'll need to remove the top of the value wheel (the plastic cap). I wouldn't recommend using a screwdriver as a lever, as you're likely to either dent the wheel or, at worst, break the shaft of the encoder underneath. Try to ease it out gently with your fingers or something that gives you a good grip.
Step 2
Now that the encoder's shaft is exposed, remove the retaining nut with pliers. Set the screw nut to one side.
Step 3
Next you'll have to remove the bottom plate on the K5000. Looks daunting but it's an easy job. Just unscrew all the retaining screws (around 25 of them!). Set them aside (note that there are 3 types of screws, just remember where they go!). Ignore the screws mounted directly to the grey metal underneath (you can see these poking out but they're not holding the black bottom plate at all.
Step 4
Find the back of the rotary encoder. It's mounted on a separate metal plate and may be partially obscured by ribbon cables.
Step 5
Because you've unscrewed the encoder from the front panel of the K5000 earlier, the encoder should be loose now. Some of the ribbon cables will obstruct it, so just lift it and pull it out gently.
If that's proving too tricky, you may want to unscrew the metal plate which holds the encoder in place. This shouldn't be necessary, but may give you a bit more room to work. Just remove the 4 screws as pictured below.
Step 6
Now that you have access to the encoder, find the four metal bits that clip on the side of the encoder. Push them outwards with a small flat screwdriver, tweezers or a small tool.
Then pull from the shaft and lift gently until it reveals the bottom part of the encoder.
There are only 3 parts on the encoder so nothing can accidentally fall out: 1) the bottom part with contacts, soldered to the small PCB (above), the top part consisting of 2) the metal casing and 3) plastic shaft with contacts (below)
Step 7
It's time to clean the contacts on the bottom half of the encoder. If there's any obvious signs of dirt, remove it first and wipe clean. Now, there are 4 separate metal plates that protrude at a slight angle. If the metal plates look 'flattened', lift the plates slightly with a small tool or tweezers so that they're at an angle of 20 degrees or so (like the picture below). They're fragile so be careful. Apply contact cleaner to the plates to finish.
Step 8
Move to the top part of the encoder. Again, remove any signs of obvious dirt first and wipe clean. Then identify the contacts on the disc at the bottom of the shaft. Apply cleaner to the contacts.
And that's it. You're done!
Make sure all the contacts are now nice and clean and without any fibres from your cloth or any other dirt. Now, reassemble the encoder (note the position of the protruding lip, this should be facing down), pushing the metal clips back in place.
Put the encoder back into its mounting metal plate
Screw the retaining nut from the front panel of the synth
Screw the bottom metal plate, put the plastic cap on the encoder, and voila! you should have a fully working K5000 again!
