Hello fluters,
On occasional cuts of wood (including blackwood and Mopane) these whiskers can be a problem. Basically, there is always some run out of the grain and where this happens the grain raises as a result of the wetting and drying cycle. This results in a defacto narrowing of the bore which can sometimes affect tone quality. Usually, however, its the headjoint bore itself which has shrunk a bit (usually in the .05mm max range) resulting in a minor loss of tone, requiring rereaming.
A careful reading my care instructions will indicate that I recommend sending the flute back to me after 6 months to a year or as needed for rereaming, which usually solves this. Folk Flute customers have to pay a small fee for this service but owners of my other flutes (including the 3 piece Rudall flute illustrated in this thread) simply have to pay for postage. Unfortunately, few of my clients take advantage of this service.
I
strongly caution anyone before tinkering with your flutes in the above described manner that doing so without the basis of experience puts your instrument at great risk! Damages resulting from such activities are not covered under any warranty and tinkering with the flute in this manner voids any further warranty, at least for my flutes! It is best to consult with the makers directly, instead of seeking advice on this or any other list where the level of experience varies.
Time to lay my cards frankly on the table: Although its great to see the enthusiasm on this list, the unmediated advice presented here frequently appears to be on the level of the blind leading the blind. I am not the only maker who feels this. From my perspective of 25 years worth of experience, I frequently find this very frustrating, especially when I commonly have to respond to bizarre questions from clients who read something scary on this list. I'd rather put that time into flute making.
Now everyone will be freaked out by bore whiskers! What next?
As to the techniques demonstrated for bore polishing - I would not use steel wool, at least in the headjoint. My method instead is to use a tapering in width sheet of 240 or 320 grit sand paper (usually 4" on the wide end and 1" on the narrow end, over the 8.5" length) taped to a 5/16" steel dowel. This is usually wrapped around the dowel, inserted into the bore, and then spun very briefly at a good rate of speed (1700 RPM with the dowel mounted on the lathe) followed by oiling with the raw linseed oil (which doesn't gum up a bore). Spinning it longer than a few moments can alter the shape of the bore. This usually follows rereaming of at least the headjoint to restore the voice (usually the body doesn't need it). I have been using this method for most of my career.
This usually leaves a matte finish. Finer abrasives can be used for a polished bore. However, I personally do not find a polished bore to be an advantage on many flutes including mine, and feel that some "tooth" is necessary and provides the "resistance" to the voicing that I prefer.
Steel wool can sometimes suddenly rearrange itself on the dowel and all of a sudden get stuck, or even cause a split when its all of a sudden too wide for the bore. At the embouchure, steel wool has a tendancy to round over the sharp edge where the embouchure meets the bore, with a very drastic effect on the voicing (especially the response of the bottom D). Please do not do this!!!!!!!!!!!!!!!!!!!!!!!!!
Casey Burns
www.caseyburnsflutes.com
The scotch bright (white) sounds like the perfect polishing tool, not only will it not grab or eat away to much, the pad is resilient to make good contact with the bore.
I've been told twice (once just today) that the cold-pressed has no additives. According to what I've been told, it's just the raw oil.
The cold-pressed is still available and, as I said in an earlier post, I have been assured by two different employees (one just today) that it is raw oil with no added driers.
that's right, boiled 
linseed oil on their instruments for years, additives and all. And, to be honest, I've rarely seen a better final finish on similar instruments anywhere. Of course they do mix other ingredients in, but still, the base linseed is boiled stock straight from ace hardware.