Globulisation!
Posted: Tue Mar 05, 2024 11:57 pm
We’re often warned about “the dangers of Globalisation”. I’m writing on a much scarier concern, the danger of Globulisation.
I was contacted by the overseas owner of a flute that was behaving badly. It’s a modern flute, but not one of mine. It’s a simple style flute, conical, with no tuning slide or metal head lining. The owner complained that after just a few minutes of playing, it went really quiet, virtually silent. The only thing I could think of was severe moisture buildup, but I’d have to add, I don’t think I’ve ever come across a case that severe.
I asked the owner to get it into its sullen state, then look up the head with the embouchure hole under a bright light. Could he see moisture in the bore, and if so, was it in the form of distributed wetness, or globules?
Massive amounts of globules came the reply. And unable to be shaken or blown out. The body bore remained dry. He added that his other flutes dribbled from the end after playing. Not this one.
I then asked him for an appraisal of whether the flute bore was smooth or rough, and asked him to both look and also to run a finger around inside. (I remember my old German woodworker Kurt Kloska saying: “your best eyes are on the ends of your fingers”.)
Very rough, was his appraisal. OK, send it to me was my response. There’s a limit to what one can achieve by remote diagnostics!
It shows up, and sure enough, is really rough in the head. And I felt didn't play well even when dry. Considerably less rough in the body, presumably because less of the condensation could get down there. The flute isn’t made of one of our favoured flute timbers, but something more in the "nice furniture hardwood" range. When I removed the cap and cork, the bore up in that area was smooth, as off the reamer. So the roughness was the effect of accumulated water, not poor initial workmanship.
I asked the owner about what oil was recommended for bore care – he advised Almond Oil. And ventured that he thought the flute had been soaked in that by the maker.
So my conclusions are that the almond oil:
- had not proved at all effective at protecting the bore from roughening,
- that it was causing the moisture to bead into globules,
- and that the roughened bore now provided a secure footing for these globules to hang out and disrupt the vacillating air column. And wreak further damage to the underlying wood!
I’ve since sanded and polished the bore of head and body back to a reasonable semblance of smooth. It took a lot of sanding, and I was reluctant to do more, for fear of altering the bore dimensions! I’d characterise the new surface as smooth but with pockmarks where the moisture had made greater inroads. It was encouraging to play it afterwards, as the performance of the smoothed flute seemed considerably better than when it arrived.
I then soaked it in a drying oil for about a day, drained and wiped it dry, then put it out in the sun to cure, rotating it from time to time to spread the curing around the flute. The sun helped this process by making its way across the sky. Nice to have friends in high places...
That’s when I noticed something I’ve never noticed before – weeping of a clear liquid along the sides of both the head and body sections. Interestingly, the weeping came only from the “quarter-sawn” surfaces (the fine grain) and not from the “flat-sawn” or “plank-sawn” surfaces, the Cathedral Spires. Interestingly there was no sign of this weeping inside the flute, just on the outside.
This I imagine is some of the remaining almond oil that had been soaked into the timber, and was now being expressed because of the heat from the sun. And weeping from the quarter-sawn sides as these offer more mobility than at right angles to the growth rings. And drawn to the sun-warmed outside of the flute, rather than the darker inside.
All I could do then was to wipe this off, which became an hourly ritual. With the benefit of hindsight, it probably would have been a good idea to try to get rid of all the almond oil before adding my drying oil, but I’m not sure how that would have best been done. And I hadn't entertained the thought it would still be liquid!
I gave the flute a little test this morning, and it seemed fine, with no immediate sign of globulisation. I’m leaving it in the sun for another day, to cure the new oil before progressing further. The weeping seems to have subsided, which is presumably an encouraging sign.
I would normally go through the oiling, draining, drying, curing routine twice on one of my new flutes, but there may be an argument to do more here. To be determined.
Also encouraging is that the exterior timber is now looking “enriched” with no sign of damage where the weeping occurred. It looks “warmer” in colour and "deeper".
So, why am I telling you all this? A few reasons….
I’m wondering if anyone has come across this situation before, a flute brought virtually to silence by moisture globules in the head. I think I remember someone mentioning the build up of moisture globules inside a metal lined head, which we traced to the inside of the slide having been unnecessarily oiled. And dealt with by mopping out with a detergent-soaked rag, followed up by rinsing and drying with fresh rags.
It would also seem to be a bold statement of the degree to which a flute’s performance can be brought down by raised grain. More than we might have expected, but then this was really roughened grain!
Perhaps to question the efficacy of almond oil in protecting flute bores? It used to be the oil of choice back in the boxwood flute days, but maybe time has moved on?
And perhaps to remind us that our favoured flute woods got to be our favourites for a number of reasons, their density, fineness and moisture resistance being some of them. And that if you want to make flutes out of less ideal timbers, a non-drying oil may not be the best bulking agent. Something that soaks in and cures or hardens would seem a better choice.
But largely in case anyone else comes across this at-first mystifying experience. This might give you some thoughts on how to proceed! Or not to proceed, depending on what we find!
I’ll add more if I learn more from what happens next. And from when it returns to its owner and goes back into service. The real test.
In the meantime, very happy to be told where I could have done better!
I was contacted by the overseas owner of a flute that was behaving badly. It’s a modern flute, but not one of mine. It’s a simple style flute, conical, with no tuning slide or metal head lining. The owner complained that after just a few minutes of playing, it went really quiet, virtually silent. The only thing I could think of was severe moisture buildup, but I’d have to add, I don’t think I’ve ever come across a case that severe.
I asked the owner to get it into its sullen state, then look up the head with the embouchure hole under a bright light. Could he see moisture in the bore, and if so, was it in the form of distributed wetness, or globules?
Massive amounts of globules came the reply. And unable to be shaken or blown out. The body bore remained dry. He added that his other flutes dribbled from the end after playing. Not this one.
I then asked him for an appraisal of whether the flute bore was smooth or rough, and asked him to both look and also to run a finger around inside. (I remember my old German woodworker Kurt Kloska saying: “your best eyes are on the ends of your fingers”.)
Very rough, was his appraisal. OK, send it to me was my response. There’s a limit to what one can achieve by remote diagnostics!
It shows up, and sure enough, is really rough in the head. And I felt didn't play well even when dry. Considerably less rough in the body, presumably because less of the condensation could get down there. The flute isn’t made of one of our favoured flute timbers, but something more in the "nice furniture hardwood" range. When I removed the cap and cork, the bore up in that area was smooth, as off the reamer. So the roughness was the effect of accumulated water, not poor initial workmanship.
I asked the owner about what oil was recommended for bore care – he advised Almond Oil. And ventured that he thought the flute had been soaked in that by the maker.
So my conclusions are that the almond oil:
- had not proved at all effective at protecting the bore from roughening,
- that it was causing the moisture to bead into globules,
- and that the roughened bore now provided a secure footing for these globules to hang out and disrupt the vacillating air column. And wreak further damage to the underlying wood!
I’ve since sanded and polished the bore of head and body back to a reasonable semblance of smooth. It took a lot of sanding, and I was reluctant to do more, for fear of altering the bore dimensions! I’d characterise the new surface as smooth but with pockmarks where the moisture had made greater inroads. It was encouraging to play it afterwards, as the performance of the smoothed flute seemed considerably better than when it arrived.
I then soaked it in a drying oil for about a day, drained and wiped it dry, then put it out in the sun to cure, rotating it from time to time to spread the curing around the flute. The sun helped this process by making its way across the sky. Nice to have friends in high places...
That’s when I noticed something I’ve never noticed before – weeping of a clear liquid along the sides of both the head and body sections. Interestingly, the weeping came only from the “quarter-sawn” surfaces (the fine grain) and not from the “flat-sawn” or “plank-sawn” surfaces, the Cathedral Spires. Interestingly there was no sign of this weeping inside the flute, just on the outside.
This I imagine is some of the remaining almond oil that had been soaked into the timber, and was now being expressed because of the heat from the sun. And weeping from the quarter-sawn sides as these offer more mobility than at right angles to the growth rings. And drawn to the sun-warmed outside of the flute, rather than the darker inside.
All I could do then was to wipe this off, which became an hourly ritual. With the benefit of hindsight, it probably would have been a good idea to try to get rid of all the almond oil before adding my drying oil, but I’m not sure how that would have best been done. And I hadn't entertained the thought it would still be liquid!
I gave the flute a little test this morning, and it seemed fine, with no immediate sign of globulisation. I’m leaving it in the sun for another day, to cure the new oil before progressing further. The weeping seems to have subsided, which is presumably an encouraging sign.
I would normally go through the oiling, draining, drying, curing routine twice on one of my new flutes, but there may be an argument to do more here. To be determined.
Also encouraging is that the exterior timber is now looking “enriched” with no sign of damage where the weeping occurred. It looks “warmer” in colour and "deeper".
So, why am I telling you all this? A few reasons….
I’m wondering if anyone has come across this situation before, a flute brought virtually to silence by moisture globules in the head. I think I remember someone mentioning the build up of moisture globules inside a metal lined head, which we traced to the inside of the slide having been unnecessarily oiled. And dealt with by mopping out with a detergent-soaked rag, followed up by rinsing and drying with fresh rags.
It would also seem to be a bold statement of the degree to which a flute’s performance can be brought down by raised grain. More than we might have expected, but then this was really roughened grain!
Perhaps to question the efficacy of almond oil in protecting flute bores? It used to be the oil of choice back in the boxwood flute days, but maybe time has moved on?
And perhaps to remind us that our favoured flute woods got to be our favourites for a number of reasons, their density, fineness and moisture resistance being some of them. And that if you want to make flutes out of less ideal timbers, a non-drying oil may not be the best bulking agent. Something that soaks in and cures or hardens would seem a better choice.
But largely in case anyone else comes across this at-first mystifying experience. This might give you some thoughts on how to proceed! Or not to proceed, depending on what we find!
I’ll add more if I learn more from what happens next. And from when it returns to its owner and goes back into service. The real test.
In the meantime, very happy to be told where I could have done better!