[sdiy] Slide pot cleaning

[rburnett at richieburnett.co.uk]

Can anyone recommend a good process for cleaning dust our of slide 
potentiometers on an old Roland SH-09?

The synth was stored underneath a bed in the spare room when we moved 
house about ten years ago, and I *thought* it had a dust cover over it!  
It turns out it didn't (>.<)  and the slide pots are in quite bad shape 
now.

The synth is functional but the sliders feel scratchy and there is 
obviously intermittent electrical contact because cutoff, LFO rate, etc 
jump around a lot when the sliders are adjusted.  The slide switches are 
okay, and the keys aren't too bad after a bit of use.

I've removed the front panel and also found that there is some sort of 
black felt/foam sheet that was obviously originally meant to be a dust 
shield for the slide pots.  The problem is that this material has become 
brittle and literally crumbles upon touching.  Can anyone recommend a 
good material to replace this with?

If I can fix the pots with a squirt of some magic spray that would be 
fantastic, but I'm also prepared to de-solder then and carefully open 
them up for cleaning if that is what is required.  I would rather take 
time to do the job properly, but not sure what is the best way to 
proceed?  I have access to a dry compressed-air line, dish soap, cotton 
buds, Isopropyl alcohol, acetone, silicone grease, 
soldering/de-soldering tools, etc, but don't want to risk making the 
problem worse without asking for advice first.

Thanks in advance for any advice,

-Richie,