Hello everyone!
I am the new owner of a Copeland high D whistle, and the tuning slide is very hard to move. I would like to lubricate the tuning slide, but I do not want to damage the whistle in any way. Does anyone have some suggestions?
Thanks,
irishmusicfreak
Hi and welcome. 
The Copeland tuning slide is just metal-on-metal, so there’s not much you can do to damage it. The fit should be tight to prevent leaks, but not so tight that you can’t easily adjust the tuning with a slow and smooth push/pull and twisting motion.
Just remove the head joint and clean the slide area thoroughly so there’s no grit, dirt or grease. Then apply a thin coat of your favorite goo - cork grease (which I use), Vaseline, brass tuning slide grease. Reinsert and wipe off any excess. Voilà, you’re good to go.
It’s a good idea to move the slide periodically even if you don’t need to, just to keep the joint from seizing up. You can re-do the clean and lube maybe a time or two per year, or when the movement starts to feel sticky again.
Good luck, and enjoy your new whistle!
The way I learned to lubricate a Boehm flute headjoint was to use nose grease. Just rub the tenon against the side of your nose before inserting it.
Some makers - Reyburn, for example - recommend exactly that.
Nose grease. Great stuff.
I’m guessing that you mean inserting the tenon into the headjoint, not your nose. Although on those nights when the Guinness is flowing it may not be all that easy to remember…
Unless it’s a Boehm nose flute!
Nose grease is a problem if you suffer from the tragic condition known as “dry nose”. Then you end up seeking out strangers to rub your whistle on their proboscises - which is a misdemeanor in 37 states.
Must be thirty years ago, but sure I recall my flute teacher recommending ear wax to aid movement between the (Boehm) foot keys as well…
Hopefully this will end the “bodily secretions as lubricants” portion of the discussion…
Best wishes.
Steve
Oils well that ends well.
I would like to lubricate the tuning slide, but I do not want to damage the whistle in any way. Does anyone have some suggestions?
I use this on my brass and aluminum Burkes. When I showed it to Mike Burke at the Dublin Irish Festival a few years ago he seemed OK with it.
The temperature range is particularly nice: It doesn’t much matter if my playing is hot or cold! 
The Burke instruction sheets also say, “Lubricate slide monthly and move slide every time you play the whistle.”