It's been awhile since I first cleaned them. Originally I did some fader cleaning with the D100 at least 3-4 years ago...???
But then a year ago I purchased that bunch of spare 3500 parts, including a couple of dozen faders.
Last December I gave my 3500 a major cleaning...faders, pots, switches, jacks...(took a couple of days). At that time, I cleaned all the faders, the ones already in the console and the ones I acquired, as they were kind of gunky on the outside ---
that's what happens when people spray cleaner just through the top of the boards into the slider cracks and the spray just goes all over everything! Some of the faders I got from him were still WET with excess spray on the outside…but NOTHING on the inside where it was needed!
Once I cleaned everything, I sorted through the entire lot of faders and picked the ones that had the smoothest operation. Those are what I put back into the console, saving the other clean ones for future spares.
When I cleaned my faders a few years back with the D100...they stayed nice thought that period, and last spring I used that console to mix my album...didn't have any issues. Of course...there's only so much that cleaning will do. At some point, they do wear out a bit, and even clean, they don't quite have the super-smooth feel of brand new ones...BUT...they have no static/noise, and work fine. That's why I picked through all of my faders for ones that also had the smoothest feel...otherwise, they all work well after the cleaning.
So yeah...let’s see what Caig has to say about which product is best for specific types of faders.
Have you tried calling TASCAM? I don't know who is left over there of the older crew in tech support...but there was a senior guy (name???) there still a few years back who was around when many of those analog tape decks and consoles were introduced by TASCAM...so he really knew all the fine details about each product.