Hello, I have a question for the flute makers or restorers.
I have been refurbishing this 8-key flute I bought earlier this year. After replacing pads, I noticed the C-key just won’t seal properly. Reason is that pad seat has a uneven surface, and the clarinet pads being less forgiving with the fit, than the closed cell foam I had on before. The roughness on surface isn’t very deep, but enough for the pad to leak even with a rubber band on. How would a flute repairer deal with this kind of issue? Also, would this be considered difficult and therefore costly operation do to?
I’m asking because I think I’d like to have it fixed by someone equipped with appropriate tools to reshape the cone. Before sending it to a regular woodwind repair shop, I’d like to know what the method of repair would be, from viewpoint of someone dealing with this type of instrument. Thanks!
-Jani
Hi Jani. I deal with this kind of problem using the tip of a very fine engineer’s needle file - half round. With great care (not to catch the blocks or the outer rim of the seat) I can scrape away around the cone’s slopes (if it is a coned bed). One can also very carefully flatten off the rim of the cone by working with the flat of the file from different angles from the sides of the hole seat. One can then scrape away at the outer slopes of the cone until the hole edge is fairly sharp again, or not - there’s no actual need to - a clarinet pad will seal just fine on a slight flat as long as the hole rim is clean and no scratches or grain tracks run across it. If there is damage, one can repair that with little dobs of wood-dust and superglue and then file/scrape it down to a matching surface. The file I use is so fine that I rarely need to use any finer abrasive, but one can wrap a slip of very fine grit wet-and-dry paper around the file if that is needed to finish off. Both cocus and grenadilla are so wonderfully workable!
You need to be careful to remove as little height from the cone as possible so as not to lower the set of the key too much - you don’t want to end up having to remedy the key shank hitting the wood of the flute because it is dropping lower (remedy either by shimming up the pad or a combination of bending the key and/or filing a slot for its shank in the body from the edge of the hole bed).
The file I use is the half round in this series. The three-square, knife and 3mm round are also very useful to have.
Of course, you’ll need to re-float the pad after…
IMO you should not need to send the work out to a wind tech. Severe damage might need a wood graft and recut of the hole seat, but no tech is likely to have a hole/seat cutter to match the antique ones - they’d either have to fabricate one to match as near as possible or use a modern clarinet/oboe one with doubtless a different profile. But I doubt it’ll come to that!
Hi Jani
I would just recut the seat using the nearest shaped seat-cutter to the original, but not all woodwind repairers are going to be set up for that. It shouldn’t be costly, as it only takes a few minutes to recut the seat, providing you are set up for it.
Do check very carefully though that the seat is the problem. Keys are very sneaky, and often you’ll find that something else is stopping it from closing completely. Open the key and let it go - be very suspicious if you hear anything like a click rather than a thuk. I like to check without the pad in place to make sure that the cup is capable of going close to the seat and isn’t being stopped by the shaft or edge of the cup or something else. Good to check at this point that the cup sits or hovers equally above both sides of the seat, and centrally. When you have the pad fitted and you think seated, use a narrow strip of cello-wrap as a feeler gauge to make sure the pad pressure is uniform all round, and that there is noticeable drag in removing the feeler. (Increase the spring pressure if the drag isn’t noticeable anywhere around the rim.) Finally, try another pad - it’s not common, but I have found a few that leaked through the tiny hair holes.
If it passes those tests but still fails a gentle suck & good blow test, you can probably conclude the seat is the problem.
Terry
Thanks for the replies. Jem’s method is what I had in mind myself, but worrying I would make it uneven and cause more troubles 
Here is a photo of the hole. It has a clear unevenness on one part of the rim, which is not very high and not too large in diameter either.
https://www.dropbox.com/s/5i06bhsp8zqgw5p/Photo%2026.8.2013%208.49.19.jpg
The flute is a Metzler kind of looking unstamped instrument. I emailed you Terry about it back when I bought it.
Using a suitable cutter is what I’d expect from a shop to do it with, but they’d need to be specialised in clarinets and oboes then I guess, to be tooled like that. I think I’ll let it be as is for a while, maybe put a softer pad on it, while figuring out what to do with it. If I happen to visit somewhere where I can see a woodwind repairer, I’ll show it to them and ask about their method and cost of fixing it.
Jani
Most woodwind repaiers don’t have bed palce cutting equipment '9even clarinet or oboe specialists). They tend to use a tone hole topper, a short cylinder of metal or wood with fine emery stuck to one end, placed into the hole and turned to leave a flat surface.
If it’s just a few chip missing I find a good quick fix is to get soem super glue on a pin head and run it around the rim to for a “meniscus” (ie the glue doesn’t spread out across the surface but stays in a self contained bubble around the rim) The gently breath your hot damp breath over the glue to encourage it to set.
I guess I was overthinking this.. I’ve spent lot time putting the keys to work, especially the foot, and this was the only one still giving me troubles, so it was annoying me a lot. 
I felt little hesitant when it comes to toneholes and embouchure, which I haven’t had to deal with before. I now see that If I filled the uneven parts of the seat, then there’s no need for me to actually remove any material, just level it to the original shape. Thank you all.