 The Oboe BBoard
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Author: RobinDesHautbois
Date: 2010-11-18 10:31
I especially hope mschmidt will read this and input his scientific approach on the matter.
The Laubin manufacturers claim that oiling the bore contributes to cracks rather than prevents them. They suggest, instead, to wax the inside with Pledge or similar using a feather.
This actually is in perfect alignment with what my brother (a 30+ year forestry engineer with special innovation work on the quality control of lumber) says on the subject. He sites several high profile studies which claim that temperature has no significant effect on wood save in the extremes. Instead, moisture leeches important aspects of the wood. He recommends sealing the wood with "some kind of wax" (but definitely keep away from Thompsons's water seal).
My brother doesn't think oiling is bad for the wood, but rather that oil lacks penetration ability and is therefore near pointless. Well, he's not a musician and hasn't as much as played a plastic recorder since high-school, but he does know wood and furniture preservation. It seems to me that sweet almond oil does penetrate the wood quite well, but I might be mistaking smudge-ability with penetration.
All thoughts are welcome on this subject. I'm especially curious about different climates - those of you from Arizona and those of you in Asia and perhaps soggy England might have some very interesting and different insight?
Robin Tropper
M.A.Sc., B.Mus., B.Ed.
http://RobinDesHautbois.blogspot.ca/music
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Author: rgombine
Date: 2010-11-18 15:11
This will certainly prove an interesting discussion, as there would appear to be no end of controversy surrounding the subject and one reads opinions from reputable individuals on both ends of the spectrum.
My Loree when transplanted from Chicago to Philadelphia cracked almost immediately and I was instructed by my local repair guy (Mallarsky) to put a small humidifier in my case during the winter months. This gadget prevented any recurrence of problems with the Loree and also kept my Yamaha professional model -- an instrument notorious for crack problems -- free of cracks for the three years I owned it.
I just started playing on a Howarth XL in April, so this will be a critical couple of months for it, but I plan on sticking with the "humidifier/routine-care" technique and hope for the best. (Howarth I believe recommends periodic oiling of the bore --
http://www.howarth.uk.com/Acrobat/Obcare.pdf.)
Just my thoughts.
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Author: Chris P
Date: 2010-11-18 15:30
As you bought your XL back in April, it should be played in by now as March/April is the best time to get any new instrument as humidity is on the rise - it'll be played in by the end of summer and prepared for the lower humidity levels as winter sets in, though still be sure you warm it up well during the winter months and always try to keep it at a stable temperature and humidity level (which is easier said than done).
Buying a new instrument in late autumn or winter is probably the best time to get cracks as humidity levels are low.
Although you can get Howarth instruments with partially lined top joint bores with bushed toneholes which will further safeguard against cracks.
Former oboe finisher
Howarth of London
1998 - 2010
The opinions I express are my own.
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Author: Jeltsin
Date: 2010-11-19 06:17
You scared me. I have a new Yamaha professional, bought in april this year and no cracks so far, but I live in Scandinavia where it will be extremly dry indoors in the winter.
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Author: cjwright
Date: 2010-11-19 13:36
No matter how much wax/sealant you put on an instrument, you won't be able to seal it completely, therefore just as you're trying to make it harder for moisture to leave the instrument, you're also making it harder to allow moisture to soak back in.
I used to be under the impression that one way was better than the other, but I think it has to go two ways. It seems to me that wood needs to be allowed to exhale and inhale the moisture and stay flexible.
Blog, An Oboe In Paradise
Solo Oboe, Thailand Philharmonic Orchestra
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Author: JRC
Date: 2010-11-19 14:21
I heard about and read about conflicting theories, testimonials, stories about oiling, and using damp-it and such. I even read that oiling inside only would cause cracking, then I read that oiling outside is big no-no. There is man in Colorado who offers service to immersing the entire wood in a magic portion and the old wood will come alive as a teenage virgin. Using some sort of treatment appears to be much more soothing to minds than to Granadila woods. Either way, it does help something.
I can only believe what I know to be true by observing the facts and supported by the laws of physics and other established sciences as far as a physical things are concerned. The Value judgments on timbre quality and musical substance are definitely beyond science. So we will not go there. The woods are definitely physical thing. Here are few facts that I know:
(1) Some woods change their surface texture with age. They seem to become dry and show more fibrous grains with wrinkles. I could see that the acoustic properties of the surface would change because of that. I have not looked into how but I would not be surprised that would cause the timbre and intonation changes, but not sure about overall pitch change (but it could). Even though the wood did not crack, such condition may not be what any one wish an oboe to become.
(2) Some even older woods still maintain shiny surface especially under the key work where it does not have opportunities to be touched much. And smooth surfaces inside the bore. It appears to indicate two things. (a) not rubbing on the surface tends to preserve the wood surface, and (b) The choice of wood by the manufacturer may have influence over aging characteristics. That may be where (the region) the wood came from or part of the wood that particular piece came from (closer to the roots, center, or ..). I actually played on an over 100 years old oboe that played in tune with good intonation. And saw all dried up looking oboe that was only 40 years old that definitely played way too sharp and intonation was out of balance and sounded bright and reedy (but some new oboes sounded bright and reedy too).
(3) Whatever oil or waxy substance one applies on the surface an oboe must be aware of the following scientific consequences.
(a) Some will dry and leave film like Thompson's water treatment. It will change the dimension of the bore. I am not sure it is such good idea.
(b) Some will eventually dry and change the PH (I think they turn acid but you should ask a chemist to be sure). Most animal oil and even some vegetable oil will do that (you should also ask a chemist if this is true). So those anti-oxidant claiming oils may be better. Actually Mobile-1 synthetic oil would be more stable than any of those but I am not sure that would be a wise move. Lanolin may be even better than the most because it is not oil, but sort of wax. It would not dry as quickly or would change as easily, chemically.
(c) Then there is a philosophical question. Do we want the oil to be absorbed or do we just want to paint the surface? Granadila wood is very dense and would not absorb much even if it did. But at some level it may. Then one would want this to be absorbed and not evaporate for a very long time. That is assuming it does not change the acoustic properties of the inner surface. Actually I heard a claim that it would darken the timbre but I have not experienced it personally. Then, one would want the oil to have good absorbing property. I do not know light and watery texture of the oil should help the absorbing property or not. But "people" seem to think that (from the recommendations I have heard). Perhaps that is the origin of "light almond oil". Then, why not grape seed oil? That is also well advertised anti-oxidant oil that is very light even lighter than the light almond oil. On the other hand, why not just paint the surface to prevent any original moisture from the wood to escape out and any contaminants to penetrate into the wood? Lanolin may not be a bad candidate because it is pretty light as a wax goes, so one could come up with a technique to apply on the surface, hopefully one molecule thick. It may even be absorbed into the wood and making a "permanent seal".
In conclusion, I am not convinced in one way or another if oiling would prevent crack. But it certainly makes people feel better about it. I would recommend keeping clean is always definitely good thing to do. But some believe rubbing would make the wood to wear out. We should all be so lucky that we could keep an oboe long enough to worry about that. Make sure your swabs are made of fluffy absorbing material that is not so tight fit and hope for the best.
Good oiling!!
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Author: rgombine
Date: 2010-11-19 21:35
Don't let me make you nervous! I think it was more a problem several years ago.
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Author: jeremyreeds
Date: 2010-11-20 02:36
I have always used almond oil with very good results, I have a 1971 Marigaux (Prestini system) which (thanks God, or the oil) has never cracked. I am sure (as many of you are) that wood is affected by humidity/dryness, and it will expand/contract accordingly. The purpose of the oil is so that the wood absorbs the least humidity so that it expands or contracts the least. I have always oiled my instrument with almond oil because that is what my teacher told me and "that was it". Nowadays I think it was not a bad idea and could not have hurt, but with my experience in reparing and restoring instruments, something that so far I do as a hobby, I think that there is another reason for this to happen.
In my oppinion, the culprit is the fact that we use metal inserts in the wood, and even though metal may not contract/expand by humidity, it is affected by temperature, and at certain moments we find wood and metal oposing each other in their expansion/contraction movements. To illustrate this it is easier to go back in time to the wooden flutes pre-Boehm. Hardly any of the head joints of these flutes has survived without a crack, a huge crack that runs all the way from the embouchure hole down to the bottom of the head joint, where it joints the barrel. The embouchure has a metal lining which is also a tuning slide (if my memory serves me well), and this metal lining expands faster? , and for different reasons, than the wood that surounds it, causing the wood to crack. Now in an oboe when you find a crack in the bell, it usually runs on the wood on top of the metal lining (socket?) and stops on the low B tone hole ( Bb pad). When you find a crack in the midle section of an oboe, it usually runs on the wood on top of the metal lining (socket?) and stops in the G tone hole (F# pad/ 1st. right hand finger). In this 2 sections of the oboe the consequences are not disastrous because the size of those tone holes can "absorved the damage" , but on the top section of the oboe, the reed socket is a killer.
If I was a manufacturer, who really cared about my customers, and the potetial problems that I would have to face due to cracking, I would make oboes without metal sockets or at the very least without reed sockets (in metal).
I hope my english writing is understandable.
Regards.
Jeremias
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Author: jhoyla
Date: 2010-11-21 07:03
Your ca. 1971 Marigaux is likely made of far denser wood than is used nowadays, and in all likelihood would not have cracked even without your oil treatment. compare the wood-grain of your instrument to that of a more recent instrument and you'll see what I mean.
I agree with you that extremes of temperature are a far more important factor than extremes of humidity. I think you could safely take a warm instrument into a sauna, but if you blow cold air onto a warm instrument - watch out! It could easily crack.
The reason for a metal reed-well are obvious - the wear and tear caused by continual insertion and removal of reeds would render the instrument unusable in a few years. I also find the metal tenon-joints to be a good thing, and when fitted correctly they will stay tight and not cause cracking.
The area most prone to cracking is the area of the trill-keys and LH 1st finger. In this region of the instrument the tone-holes and posts are packed tight together, the wood is relatively thick (compared to the bore) and this combination - when subjected to extremes or sudden changes of temperature - is more likely to cause cracking than any other.
What is the general opinion about humidifiers? I read somewhere that they are a primary cause of rusting (springs, screws etc.) and that they do not help the wood in any way.
J.
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Author: rgombine
Date: 2010-11-22 00:17
Re: rust and humidifiers:
I have never had a problem with rust, but I am always careful not to place humidifier directly next to key work. In the winter, I take the reed case out and leave the humidifier in the the place the case usually goes.
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Author: jeremyreeds
Date: 2010-11-22 23:16
Hello Jhoyla (Jeremy), regarding your statement "The reason for a metal reed-well are obvious - the wear and tear caused by continual insertion and removal of reeds would render the instrument unusable in a few years", I do not quite agree with such reasoning. In the 1800's, I believe oboes did not have a metal reed-well; as a matter of fact, I have an English Horn (cor anglais) ca.1890's, which has only a decorative metal ring around the bocal-well, and I still play it; the modern English Horns all have metal bocal-wells (suckets), similar to the modern oboe's reed-well.
I think that one would have to spend a lifetime, and probably part of another, inserting and removing a greased corked staple, in and out of the (wooden) reed-well of an oboe, in order to reduce its diameter by 0.1 mm. ; but that is not really important, probably if I was an oboe maker, who needs to pay his rent, would realize that one must CAPITALIZE ($$$) on legends, cliches, superstitions, etc., and I instead should offer oboes with reed-well in platinum, gold, sterling silver or our regular most popular german silver (nickel silver); I would follow by giving my customers the speech that flute players get, regarding the qualities of sound that each of these metals delivers.
I do not mean any offence, I just wanted to share some humor.
I do agree, instead, with "The area most prone to cracking is the area of the trill-keys and LH 1st finger. In this region of the instrument the tone-holes and posts are packed tight together, the wood is relatively thick (compared to the bore) and this combination - when subjected to extremes or sudden changes of temperature - is more likely to cause cracking than any other". It is only natural that the crack follows the path of least resistance - the path of the grain of the wood which is naturally the weakest or has been made the weakest during the manufacturing process (like drilling holes along the path of the wood grain). In other words, we can, with a high degree of certainty, predict where the crack is going to happen, before it happens. I imagine it this way: if we have a chain and we pull on it from both ends, we know that it is going to break at the weakest link, we do not know before hand which one it is. If we drill a hole or two in one of these links, we know for sure where it is going to break, except if there was a link which was 'naturally' weaker than the one on which we drilled the holes. Now, the important thing here is to realize that the break would not necessarily happen at the ends of the chain where it is being pulled from. In the top joint of an oboe, given the worst conditions (like in the middle east), very dry (wood wants to shrink), and very hot (metal wants to expand), the wood is under stress where that piece of metal and wood meet, but the crack will not necessarily happen there, just like in the chain, the breaking does not necessarily happen at the point where the chain is being pulled from.
Humidifier? I have never used it but I think it is a good idea, at least one of those variables (humidity/temperature) is kept constant as long as possible.
Regards
Jeremias
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Author: jhoyla
Date: 2010-11-23 08:51
Actually, here in the Middle East cracking is quite rare, since temperatures almost never go below freezing, certainly not indoors. The problems are mainly faced by players in really cold countries, as pointed out by Nora Post: http://www.norapost.com/instructions.html
She claims (I can find no other references to this):
Quote:
It is no accident that the Scandinavian governments replace all the oboes of the oboe sections on a regular basis, gratis, because of the cracking which results from the cold weather.
J.
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Author: RobinDesHautbois
Date: 2010-11-23 10:26
I consulted with my brother, the forrestry engineer, again. We compared instrument cracking to hard-wood floors getting loose in the winter because:
1. that's something we both understand and it is visually clear what is happening
2. it provides a good understanding for the mechanics of what is actually happening
=> hard wood floors get loose in the winter and push against each other tight in the summer. Over here, we get cold dry air in the winter and hot humid air in the summer. I'm supposing its the same thing in Scandinavia and Siberia (please correct me if I'm wrong).
In agreement with the scientific studies (sorry, I don't have the references, but I can ask if anyone is interested), temperature is not the problem, but changes in humidity - however, the very numerous metal screws will contribute to cracking based on temperature: differences in expansion rates will add excess strain on the wood. All the cracks I have seen are around the octave and trill keys (many, many post screws there) and around the F# joint around the metal socket: even in the bell around the socket over the Bb hole.
The purpose of swabbing the instrument is not so much to reduce humidity, but rather that water leeches out natural elements of the wood: water "dries" the wood. So those of you with really old instruments that have never cracked and have never been oiled, it's probably due to good care.
This is probably why Laubin suggests waxing with Pledge sprayed on a feather. I can't find lanolin around here except for sckin care creams.... I'll continue to look (perhaps in automotive under rust-proofing?)
Thanks to everyone for a great discussion!
Robin Tropper
M.A.Sc., B.Mus., B.Ed.
http://RobinDesHautbois.blogspot.ca/music
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Author: JRC
Date: 2010-11-23 14:41
The temperature and moisture contribute to expanding and contracting of the wood. I do not have the data to back it up but I would venture to guess that temperature affects more overall. Moisture (wetness) would affect more "locally" where wood surface is in direct contact with water and saliva. This observation is based on the fact that grenadilla wood is dense and does not absorb water like a blob of sponge would. But the wood surface would become "wet" and some local absorption is inevitable. Molecules of any wood will expand when wet. It is especially troublesome when the temperature difference between the blowing air and the wood surface is "high"; more condensation. If you are salivating over wonderful music you are playing, it will get even worse. I would not worry too much about moisture absorption into the wood from the moist air. It would be much less effective in getting into the wood than water in direct contact
So, the internal surface of the oboe bore would expand relative to the rest of the wood by higher temperature from warm blowing air and the water absorption by direct contact. The wood will experience stress from this local expansion of internal surface. The level of stress is higher if the temperature difference is higher and wetness level is higher. The wood can stretch to relieve the stress, one would hope. Bamboo wood would stretch much more than grenadilla wood would, so, grenadilla wood is more likely to crack under the stress than bamboo to relieve the stress.
If you look into the bore from the bell after playing about 15 minutes, you will see moisture starts to condense all along the internal surface. Depending on how dry the room, it may already be dripping water. But you will also see that there is more water closer to the reed socket. The dripping water channels down along the bottom wall. Now you know why all the tone holes are located along the top side of the wall so the water will not plug up the holes.
The closer to the source of the warm and moist air from your reed, the more condensation and the warmer the internal surface would be. So, the upper top joint would experience more stress from temperature and moisture. It also happens that the ratio of diameter to thickness is the largest there also. The stress experienced by the wood would go with this ratio. Now you can see that the top of the top joint will be stressed the most.
The crack would most likely happen at the weakest point. Holes and posts contribute to the stress on wood and therefore weakness. Just look at the top joint of the oboe. There are high concentration of weak points around the c# and d trill holes. There are metal posts, tone holes, and octave holes. Guess where the most frequent cracks point in oboe would be? The stress has to be relieved and crack will be the natural course.
Now let us review what we have here. Higher temperature differential and direct contact of water with wood surface provides the cause and high concentration of holes and post provides the failure point of the cracks. I did not mention any thing about cracks around the metal piece at the top of the middle joint and the bell. Phenomenology is very different there and they are much much less serious problem.
What should we do to minimize the possibility of top joint crack? I can think of 3 things.
1. Reduce the temperature differential as much as possible.
a. Warm up the oboe, especially the top joint before blowing into it, like putting it under your arm inside the coat or holding it with your warm hands (hopefully your hands are warm)
b. Avoid blowing hot air into the cold oboe. No No No! It would be better to blow from the bottom instead of from the top, if you really want to blow into it.
2. Minimize direct contact of water with the wood surface. You can actually stop this altogether by applying water repellant over the wood surface. Use your favorite magic portion but consider the following;
a. Do not use any thing that will leave film. Thompson’s water seal is no no.
b. Avoid using things that would damage wood in long term. Animal fat tends to turn acidic in time (you should check this with credible chemist to confirm this). I was told that acid is not a good thing to wood (you should check with experienced carpenter especially custom cabinet designer/makers to confirm this). On the other hand, if you keep oiling it before it turns acidic, that might solve that problem. I was told that high unsaturated oil content (they call it anti-oxidant) would lessen the probability of turning acidic. There is something called Emu oil from Australia that has very very high omega 9, a form of unsaturated oil. (This is a good place for a chemist to jump in.)
c. If the magic portion can be absorbed into the wood and permanently seal the surface from water, that would be perfect. BUT, too much of it could change the acoustic properties of the wood surface and could affect the timbre. Do not forget you paid an arm and a leg to buy that oboe for that wonderful sound.
d. Lose that feather to spread water all around the surface! Bad idea! You should remove water not spread around to make the situation worse. Use something that absorbs water. Use something that does not rub the surface, which would also rub off the water repellant, then you will have to apply it again and again, and who knows, it may change the tone color of the oboe.
3. Spread the stress points and reduce the density of the holes and post. The trill holes do not need to be next to each other right next to the post and right under the octave hole. On the other hand we, the players, have no option. I hope the manufacturers understand the physics and do something about this. They can also condition the wood to repel water especially the top joint as a part of the manufacturing process. Telephone phone pole and railroad tie manufacturers do it. Even some lumber woods are treated for long term. Why not the oboe manufacturers?
By the way, if any one wants to try lanolin, I bought one from Amazon. http://www.amazon.com/gp/product/B00028MLKC/ref=cm_cr_rev_prod_title
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Author: mschmidt
Date: 2010-11-23 17:41
I find it hard to believe that the temperature coefficient of wood expansion is greater than the humidity coefficient of wood expansion. In other words, I would think that the wood is more subject to stress by changes in humidity than by changes in temperature. If, in fact, oboes tend to crack more in the winter, it's probably not because it's cold outside--it's still room temperature inside, where the instrument is being played. Rather, it's that 50% relative humidity outside at 0 degrees C means that, when that same air is brought indoors and heated, relative humidity will be much lower (10-20%). This means the air will be more drying. The inner bore surface will get to 100% relative humidity when the instrument is played (that's why you get condensation in the bore) and it seems very likely to me that the differential humidity between the inner surface and the outer surface would create the maximum stress on the wood.
Of course, it is also possible that an instrument carried outdoors in a poorly-insulated case might be subject to sudden changes in surface humidity and temperature, and the slowness of water and/or heat transport from the middle of the wood (away from either the inner or outer instrument surfaces) may result in differential expansion/contraction and stress on the wood. But, again, I'd bet money on humidity changes being a more likely factor in cracking than temperature changes. For one thing, the transport of heat in dense grenadilla wood should be several orders of magnitude faster than water transport.
One thing I have never seen is a compilation of cracking statistics. Where was the instrument when it cracked? Was it being played? What was the ambient temperature? What was the ambient humidity? How frequently was the instrument played? How was it swabbed, and how often? Was the bore oiled, and how often? All our musings on this thread are just speculations without any empirical data. I suspect that most incidents of cracking occur in poorly characterized environments, and that misconceptions about the causes of cracks may lead to selective and even erroneous reports of conditions. (There must have been a draft from under the door!) Even with this data, we still might be helpless to reach a solid conclusion about what presents the greatest risks or how to avoid them. Every piece of wood is individual. There may be multiple risks that affect different pieces of wood differently.
I once was trying out a cracked oboe. The owner said that her teacher thought it was a good sign that the oboe cracked, since it meant she (the owner) was finally putting a proper amount of air through the instrument. This is really the most ridiculous explanation I have ever heard, and makes hardly a whit of physical sense. But it was stated by a professional oboist, so it must be right, even though the education of a professional oboist probably involves a minimum of physics and chemistry! I am afraid that the cracking of oboes is another one of those minefields for musicians--a situation in which even the best physical scientists would have a hard time sorting out all the variables, but where the hapless musician, in hopes of some sense of regularity and control, is left with nothing but hearsay and myth to guide him or her.
As a scientist, I accept that my oboe may or may not crack, and that I should reasonably protect it from extremes of humidity and temperature. I occasionally oil my bore, just on the idea that I am restoring some plasticizers that the wood may lose through oxidation or leaching (that drip down the back of the bore). But I know I have no idea whether I am doing any harm or good in my daily practice, and when and if the instrument cracks, I still will not know.
I think the best way to avoid cracks is to buy an instrument that's at least five years old and has no cracks!
Mike
Still an Amateur, but not really middle-aged anymore
Post Edited (2010-11-23 17:44)
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Author: mschmidt
Date: 2010-11-23 17:49
I have been using lanolin on my corks and they've been falling apart like crazy. Coincidence or cause-and-effect? I don't know. But I could imagine that there may be bacteria and/or fungi that are deterred by petroleum-derived oils but feast on a lanolin-cork combination. But it's just speculation. It may also be that my instruments, shut up in a safe with a trial instrument that reeked of contact cement solvent, may have had the cement holding the corks on fall apart due to this solvent exposure. Or, maybe it was just time for my corks to fall apart.
Mike
Still an Amateur, but not really middle-aged anymore
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Author: mschmidt
Date: 2010-11-23 18:14
If anyone knows anyone who has a lot of useless grenadilla scraps lying around, have them contact me and I will gladly try to make some statistically significant studies of cracking behavior in drilled grenadilla wood scraps. Maybe not the same as a real oboe, but at least it would be better than thrice-repeated anecdotes.
Mike
Still an Amateur, but not really middle-aged anymore
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Author: JRC
Date: 2010-11-23 18:27
There are several degree F difference in room temperature from winter to summer. Most people try to save cooling and heating bills except perhaps those live in California with little or no seasonal variations. There are indications of "statistics" on where and when cracks happen in Nora Post, and most large repair shop websites (not scientific data per se but many years of observations).
Most shops sell cutting blocks made of grenadilla wood piece.
Post Edited (2010-11-23 18:41)
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Author: JRC
Date: 2010-11-23 18:50
They also sell liquid form of lanolin in a consistency of light honey. I found one in Amazon.
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Author: Bobo
Date: 2010-11-23 19:54
I've been using lanolin as cork grease too and haven't suffered any damage to the cork. I apply it as sparingly as possible so there is no residue. I find that with standard cork grease it's easier to overgrease the corks to the point that the joints tend to slide apart (then you wonder why you're suddenly playing flat or the bridges aren't engaging!). I also use the lanolin very very sparingly for new staples so that they don't get stuck in the reed well (just an imperceptible amount on the lower quarter inch).
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Author: kimber
Date: 2010-11-23 20:05
I have no scientific knowledge on the subject of wood swell - however I can report that the bell ring on my Loree has consistently (20 years) been loose enough to easily twist during fall/winter/spring and tightens up for summer in my Wisconsin environment despite regular use of humistat and general household humification.
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Author: RobinDesHautbois
Date: 2010-11-24 10:36
I have to look up the website of the FPS (Forest Products Society, Madison, Wisconsin) - apparently they have lots of litterature on the subject.
It seems that temperature has no effect on wood expansion: its all humidity in the air. Again, in Eastern Canada: cold=dry and hot=humid.
kimber wrote:
Robin Tropper
M.A.Sc., B.Mus., B.Ed.
http://RobinDesHautbois.blogspot.ca/music
Post Edited (2010-11-24 12:47)
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Author: JRC
Date: 2010-11-24 13:24
Your information is absolutely true in most wood concerning communities where the woods they deal with are commercially significant. Nearly all of them are lighter than water (scientists like to call it specific gravity or simply mass density). They all float on water. Oak is considered dense or heavy wood. Its mass density is around 0.75. Pine is between 0.3 and 0.5. Standard practice of cutting and shaping these woods are to use saw or standard wood tools.
Grenadilla and ebony probable are the most dense. Mass density around 1.3. They simply do not float on water. Standard wood working tools do not work with these. Instrument manufacturers and repair people use metal working tools to shape these woods.
Mechanical properties of these woods are between "wood" and metal. The higher the density. I just wanted to save you from lots of not necessarily relevant research on oboe cracking issue.
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Author: jhoyla
Date: 2010-11-24 15:11
I tend to agree with JRC.
The stresses caused by moisture may cause small cracks to form over time, but humidity changes inside the wood are likely to be gradual, not sudden.
The stresses caused by temperature differences can be very sudden and are a far more likely cause of massive cracking that can destroy a top-joint. There is a reason why all of the oboe web-sites tell you to warm up an instrument in your hands or armpits before you play them.
There are stories such as Susan's (please correct me if I am wrong): She left her instrument out during the interval of a performance in a cold draft, and actually heard it crack through the tone-holes.
http://www.woodwind.org/oboe/BBoard/read.html?f=10&i=9724&t=9721
If humidity had been the primary cause, it would have cracked while she was playing it - not after she stopped. It cracked because of the sudden temperature difference between the outside of the instrument and the inner bore. I know, I know - one case is hardly a statistically valid sample.
J.
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Author: RobinDesHautbois
Date: 2010-11-24 17:01
Well, anecdotal evidence may not a scientific principle prove, but there comes a point where increasing smoke must mean SOME fire!
The point that bothers me the most about temperature is the metal ring becoming loose in cold weather... I have experienced that too. If wood does not contract with the cold (expand with heat), then the metal ring would do the opposite. Perhaps sudden shifts in temperature and humidity (drafts would dry up the air), might cause worse effects than gradual changes. There is also the issue of air temperature versus wood temperature: if the instrument is left in the blinding stage lights, chances are the wood remained warm despite the ambient drafty air.
I think there is also an issue with age: I have been practicing every lunch time (in my car) on my 1921 instrument in all types of weather. Last week was constant rain, now its starting to get cold: I'm not too worried about cracks as it has already cracked (who knows how long ago) so terribly that it has 4 metal bands on the top joint. The only "open" crack is above the F# key: not wide enough to bother filling. But I'm still amazed at how consistently (poorly, yet consistently) it performs.
The story about poor oil penetration bugs me. This old instrument came to me so dry, I thought it had been painted: the tone holes were red and the outside black. I oiled it with sweet almond oil and after a few applications, it became apparent that the wood is authentic. It has remained nice until a few days ago: I'll oil it again..... I like the smell anyway!
I'll keep practicing until the sun no longer heats the car enough for reasonable comfort: I'm now wearing a leather coat and cycling gloves (no heater: can you imagine the cost in gas of idling 30 minutes each day?).
Robin Tropper
M.A.Sc., B.Mus., B.Ed.
http://RobinDesHautbois.blogspot.ca/music
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Author: johnt
Date: 2010-11-24 17:09
The best advice I've seen anywhere inre playing the oboe is the wisdom on Peter Hurd's superb website wherein he says to warm the oboe top & middle joints up by wedging the tenon ends under the armpits & gently squeezing down on the joints with the upper arms for at least five minutes before even thinking about blowing warm air into the bore. "Hatching them" is the metaphor he uses. Irrespective of temperature, this should be done no matter what the ambient temperature is. The difference between room temperature 68-70 degrees F. & body temperature 98.6 degrees F. is over 30 degrees. If it's any colder in the room, the potential for cracking increases even more. However, if the oboe is warmed up a la Hurd, the prevention of cracks more closely approaches reality.
Best,
john
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Author: Oboe Craig
Date: 2010-11-24 17:44
Here in Colorado, it gets so dry in winter the wood shrinks and the keys bind.
I used to use sweet almond oil but switched to Larry Naylor's custom organic bore oil 3 years ago.
Even using that a couple times a year, the wood shrinks. Then I take my oboes and english horn into the bathroom after a shower and give them a sauna...
Last year I started wiping down as much exterior wood as possible without removing all the keys, and think I will keep doing that a couple times s a year now on.
In dry weather, I also have tried making sure I put the oboe in its case when I am not using it, and place fresh orange peelings on a baggie inside the case keeping the orange acids off the keys.
I've had one Covey for 25 years and no cracks, the other Covey I got 2nd hand when it was hardly played but several years old. I broke it in using Paul Covey's method and no cracks, yet.
My former Loree I bought from Paul and broke it in his way, and no cracks.
When I asked Paul about the oil, he said he had soaked a block of grenadilla in oil for a few months, then cut through it to see how far the oil penetrated and it had barely penetrated the wood.
Post Edited (2010-11-25 04:11)
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Author: mschmidt
Date: 2010-11-25 04:04
I'm sorry to be such a pain in the neck, but I have been trained to be skeptical--by both my research mentors and my experience as an experimental scientist. You say "If humidity had been the primary cause, it would have cracked while she was playing it - not after she stopped." Well, maybe. But the transport of moisture through the wood would likely be slow--the high-moisture front could be traveling outward through the wood even after she swabbed the oboe and left it out in the theater. The stress that could have caused the crack might have little to do with the ambient conditions in the theater--the wood may have dried from the outside in over the course of a few dry winter weeks, and the high-stress interface between wet and dry could be several mm in from the surface.
It seems your statement could just as well have been "If temperature had been the primary cause, it would have cracked while she was playing it--not after she stopped," because the temperature difference between her breath and the ambient air (90 ˚F and 65˚F, if it's an unheated theater, for a ∆T of 25˚F) while playing was probably as great as, or greater than, the difference between the ambient air (which quickly filled the oboe when it was no longer played) and the cold draft (65 ˚F vs. say, 45˚, for a ∆T of 20˚F) when the instrument was sitting out during the interval. Of course, all these temperature estimates are just guesses--which is why we should be reluctant to conclude anything from this anecdote.
Mike
Still an Amateur, but not really middle-aged anymore
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Author: RobinDesHautbois
Date: 2010-11-25 16:09
The metal ring issue could be also caused by relative humidity. Recall that, at least in this part of the world (including New-England, USA), cold in winter means dry and hot in summer means humid (not quite so clear around Windsor/Detroit).
So wood shrinkage from dry winter could outpace metal contraction from the cold. After all, I have always played in heated buildings. In fact, the older buildings in Montreal were quite overly heated...
Robin Tropper
M.A.Sc., B.Mus., B.Ed.
http://RobinDesHautbois.blogspot.ca/music
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Author: colloquial42
Date: 2010-11-28 00:58
Just a comment on the humidity vs. temperature debate. I've periodically had issues with metal reed-well on my Yamaha pulling out when removing reeds. This has only happened a few times, and always in winter when I've been lax about refilling the humistat. I refill the humistat, toss it back in the case, and in a few days, the reed-well is once again snug. My $.02, yours may vary.
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Author: GoodWinds ★2017
Date: 2010-11-30 18:39
if you are serious about finding lanolin, you might try asking at a pharmacy, probably not a chain-store brand but a compounding (custom) pharmacy. They can get pretty pure-grade stuff, I've NO idea what the price would be.
THe last time I used pure lanolin was when I lived in Canada in the 80s.
I'm not sure if it would be good for wood or not; I do know that one should be very, very careful around any pads, because it can be pretty sticky...
GoodWinds
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Author: GoodWinds ★2017
Date: 2010-12-02 20:20
I would tend to agree; after using the stuff (lanolin) on my body, I would be VERY hesitant to put it into my oboe...
GoodWinds
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The Clarinet Pages
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