For those of you who have been employing a mag machine to quantify their work, and done so long enough to have an opinion, these are the readings I got when I checked my Pearl 765. I have had a couple leaks repaired and have not touched it myself (nor do I intend to for a loooong time, if ever :
Head joint: 0
Body: 2.5
Foot joint: 2.7
Body and foot joint together: 3.3
Mag set at 4 inches of water @ 1 scfh.
When testing other flutes as well as this one, I have noted that the greatest amount of leakage seems to occur at the pads that are held closed by a spring (i.e. G# and D#(Eb). Providing even the very slightest extra pressure exerted by a finger on one of these keys reduces leakage of that pad to almost zero.
Do you approach re-padding these keys differently than you do other keys? What are your experiences regarding these keys?
HMannfan wrote:
Mag set at 4 inches of water @ 1 scfh.
Your first issue is that you should be at 8 inches of water @ 1 scfh.
4 is much too low. You need to qualify not just the reading, but the rate of needle plunge (even if that is a bit more subjective). At 4 you can't gauge the closure response and has insufficient pressure to identify certain leaks.
You also need separate readings for the body and footjoint.
Thirdly, are you also using an isolator for individual pads? Necessary for just the pad, pad installed in keycup, and isolated tone hole and closed key?
Once you make corrections and retest for your data, we'll have a better idea of what you need to do..
I'll second the comments from Joe and Steve. In particular, I agree that a setting of 4 is too low. 8 is the recommended setting in the instructions. Also, Joe's comments about the isolator are right on. Reading the entire body or flute simply shows that there is leakage, but it doesn't show where. Using a leak isolator makes the Mag much more useful. Lastly, regarding normally closed keys like the G# and D#: Even though the mag has very low air pressure, when the tube is plugged with a stopper, it is still enough pressure to blow open closed keys and give the appearance of a leak when in fact, the pad may be sealing properly. While the Mag is an excellent diagnostic tool, a play test is the final authority.
"Never give a flute player a screwdriver."
--anonymous--
I find that when you slide the isolator under a tone hole, I can visually see the walls lightly deform, this in turn alters the pad touch surface, so if you were to measure an individual pad, then it will get you close. But Im a close is not good enough person.
I would only use the isolator as a block tool for say the upper half of the flute or the lower half not for checking a specific tone hole
O.K. Thanks for the input. Here are the new readings taken at 8 in. of water and 1 scfh and recording the rapid response numbers using normal finger pressure (relatively light). The needle does fluctuate some up or down a little after the initial response:
Body: 6
Foot: 6.4
Using the isolator from J.L. Smith and normal finger pressure:
D key: 4
E key: 6
F key: 2.2
F# key: about 6 using any key D, E, or F.
With deference to Steve's advice I used the isolator in the body to separate it into upper (G and above) and lower sections (F# and below) and only normal finger pressure:
Just to test Steve's suggestion that the isolator may deflect the flute body slightly, I used it on the flute body tenon and tried to slip on the foot joint. It was very difficult to do so with the expansion caused by pressure from the isolator. I could not observe this visually like Steve could, but his point is affirmed and well taken.
The flute plays fairly well, but I've always thought the lowest register was sluggish and difficult to play. I'm a fairly good flute player, but I have little experience with a decent quality flute. This flute is an upgrade from my old high school band instrument. I have always thought the new flute should play better. I think the mag numbers speak for themselves. I expected better results than this. If I send it out to a flute specialist and pay $300 or more for a tune-up, should I expect better number than this? I'm hoping that improving the leaky pads would improve performance of the lowest register.
I do appreciate the fact that the mag machine is only a tool, and that how the instrument plays is the bottom line. However, it is also indicative of how well the padding is performing and the need for some service. I have been using a feeler guage to check the keys periodically and had reason to believe all was not well. The mag seems to confirm the fact that it is time for some serious attention.
Any comments or opinions would be very welcome and appreciated.
Without being present, it sounds like you have leaks.
You should regulate your flute as normal with feeler strips
At satisfactory completion you should test play and there should be no hesitation.
A pressure check, should show rapid movement of the needle to under 3
A well set pad can achieve 0-1 on the gauge
If you have readings as you have indicated then I would recommend clocking all pads at 8 locations rather than 4, I also suspect it doesn't play okay well either, which means you've skipped the steps I indicated earlier
If it still eludes you, then remove all keys of instrument, plug all holes and check pressure after fitment of each key
If you are having your flute serviced by someone else and your merely checking and you get readings like you indicate then take it back to them and explain the situation.
Steve, I am not servicing this instrument myself. I am merely using the mag to verify that this flute needs repair, because I am not happy with my tone nor the response of the instrument and suspect there are leaking pads. After the use of a feeler gauge, I saw the mag as a final definitive tool to test my suspicions.
I bought this Pearl flute new. I have done nothing to it other than play it for about 3 years. I started taking flute lessons shortly after I bought the flute, after a long absence from playing (45 years).
I had the local repairman do its last COA about 7-8 months ago just before he retired. It played O.K. for a short time, but has since gone down hill. There is no other competent repairman for flutes here. I am not competent to repair it myself.
I have an old Selmer Signet student flute that I am attempting to repad myself just for the experience and to gain an understanding of the processes involved. You know, just for the *ell of it.
With out knowing your other repairer and not wishing to cast dispershions, it is quite common amongst those repairers who cannot repair flutes to simply clamp to death the flute pads, which means it will play relatively fine for a month or two and then start to leak as the impressions start to dis-appear.
A well setup flute can go for many years with very minor adjustments
Thanks a lot for the replies. All the pads appear to have well defined impressions-maybe too deep. The repairman wasn't a flute specialist, but he was the only person in my area anyone would even suggest to have work on a flute. After reading as much as I have about flute repair, I can understand why.
The flute is only three years old but may need a re-padding none the less. When I began playing again after purchasing this flute, I know that my touch was much firmer than it has become since.
I guess my best guess decision would be to simply send it out to a flute specialist I know of in Berkeley, CA. He is well respected and trusted, but expensive. A complete re-padding would probably cost $500 - $600, but it would be well worth it to me to have the flute playing at ITs best so I would have the opportunity to play at MY best. I am so tired of playing leaky nonresponsive flutes.
Having read your many replies in this forum and others, I would not hesitate to send it to you if you were in the U.S.A.
I find that when you slide the isolator under a tone hole, I can visually see the walls lightly deform, this in turn alters the pad touch surface, so if you were to measure an individual pad, then it will get you close. But Im a close is not good enough person.
I would only use the isolator as a block tool for say the upper half of the flute or the lower half not for checking a specific tone hole
But thats me.
I understand what you are saying about the isolator, but I've only seen the wall deformation when the tool is adjusted to apply too much internal pressure. When properly adjusted, I don't observe that issue. The only exception may be on gold thin-wall flutes. I have a 14K head and applying finger pressure on the tube, it will flex. I would expect the same on a gold thin-wall flute body.
But, everybody has their preferences, and while I respect your opinion, I don't find it to be a problem under typical usage.
Bob
"Never give a flute player a screwdriver."
--anonymous--
@HMannfan: If you are thinking about getting a pro flute tech to repair or repad your flute, tell us your approximate location and we may be able to help you find a good tech that is close to you. There are quite a few well respected flute techs out there that can make your flute play better than new and we'd be happy to offer some recommendations for techs!
Also, if you are not repairing flutes, I'm curious why you have a Mag tester just for checking your flute. Do you own one or did you borrow it? Mag testers are a bit pricey, even if you build one yourself and it's usually a tool used only by the better flute techs.
"Never give a flute player a screwdriver."
--anonymous--
pied_piper wrote: I've only seen the wall deformation when the tool is adjusted to apply too much internal pressure. When properly adjusted, I don't observe that issue.
Bob how are you managing to adjust, have they revised the tool, mine simply, is a turned piece of white delron with two grooves for O'rings and a pressure hole, this is as purchased from Jeff.
HMannfan wrote:Having read your many replies in this forum and others, I would not hesitate to send it to you if you were in the U.S.A.
Thanks, Im sure there are many fine repairers in the U.S, the trick is finding them, the downside is, usually when you do find them, there is always a cue of instruments in front of you..
My cue is approximatley 60 instruments at any one time are waiting to be repaired, I feel extremely bad, having an instrument sit on the inbench (recievals area) for a couple of weeks just to get 10 ft from there to my work bench.
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