I think for the most part, Chris said it best -
From my own experience - anything can be embedded with other types of vibrations (on the sub-atomic level everything vibrates!). I guess there might be a few different types of "energy contamination" that we deal with here.
When it comes to pendulums to overcome the remnance (or remanence) - in most cases it's enough to knock it a few times (some say odd number, but I don't find it true) on the hard edge of the table or such. (Energy pendulums like the Isis or the Karnak don't require neutralizing or energy cleansing).
To neutralize the string - you can slowly run the blunt (dull) side of a knife or any metal object with high iron content.
The simplest method yet is to hold the pendulum (or other object) in your hand and ... ask to be neutralized from any vibrations it picked up (you may specify non-beneficial or those that may interfere with your dowsing). That's it!
OtterWater said -
So was I mistaken in thinking that the Super SIx clears itself as well?
The Super Six is, in fact, an "Isis" pendulum, so indeed, it is self-clearing, Otter
I have heard of placing quartz & other gemstone pendulums in the sunlight or moonlight for a minimum of a half hour to charge & neutralise them. I also recommend holding them under some cool running water, too... Kyanite, I've heard, is the most "neutral" of all gemstones - so that makes sense. As far as creating your own pendulum clearing program, that sounds like a great idea, albeit a bit more complex than the water filter, IMO. But, if carefully worded, with the right intentions, I see no reason why that wouldn't work fine...Blessings, NL