Well, I don't know that there is an absolute "correct" answer, but here is what the lads on Bob Dunsire's forum seem to think!
"That said, there's no proof that highly polished bores create better tone. The old bagpipes, made on treadle lathes, don't have polished bores and yet they produce the best tone. Besides, the tuning chambers and drone bells don't have highly polished bores, and it's often said that these sections of the drone bore are what produce the better tone.Then again there are those who say 'its all in the longjoint bore.'
A polished surface allows water vapor to condense far more rapidly than an un-polished surface because you're decreasing the surface area of bore.Compare this to frosted glass vs smooth glass. Water vaper condenses to form droplets far more quickly on smooth glass than on frosted glass.Mark
I remember a fad for drone polisishing some years back. Several Highland bagpipe dealers advertised the service. Aside from removing metal burrs and paper curls with pictures of queens and presidents from the drone who ordered the polishing, I never heard any improvement in tone. And not one experienced player I have ever asked has said, "Och, aye, you must get that done, and straight away!" Several suggested that they haven't even got a clue what their bores look like, really. As Iain, Richard, and Robin are saying, it may not do a thing for your tone. Do any top players swear by polishing?
Twenty years ago I polished the bores of my drones and noticed a slight increase in volume and brightness. I'm not entirely certain it was worth the effort. Mostly I concentrated on the bottom joints of each drone. I did the polishing with a piece of drill rod held in a variable speed drill. I wrapped the end with two sided tape and then twisted steel wool onto the tape to make a polishing head. With fine steel wool the effect is more of a burnishing than removal of material. I finished up with a twist of nylon stocking soaked in bore oil. The bottom joints came out very slick indeed.
From Bob Dunshires forum:That said, there's no proof that highly polished bores create better tone. The old pipes, made on treadle lathes, don't have polished bores and yet they produce the best tone. Besides, the tuning chambers and drone bells don't have highly polished bores, and it's often said that these sections of the drone bore are what produce the better tone.Then again there are those who say 'its all in the longjoint bore.'
From Bob Dunsire's forum:
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