Humidity and tuning

[windhorse]

For what it's worth, I agree with Bongo..
I just tune my drums every time I play, and don't believe in detuning.
Seems like a waste of energy if you play your drums often. Since you're going to do a little tune check when you pull them out to play - in my case almost every day, then you may detune or tune the head up and then you play.
If longevity of the head is your reason for detuning, let's add another factor more along the lines of Bongo's analogy of the engine. The lugs. What happens to the screw and nut under repeated detunings? Isn't this an area of stress and wear? And what about the bearing edge and seating of the head against the edge? I've personally witnessed a guy who repeatedly detuned heads, and he wondered where all the buzzing was coming from when he hit the head hard. Another friend who has taught me everything I know about tuning mentioned to him that he detuned them too far and let tiny air pockets get between the head and bearing edge and thus was the cause of his buzzing problem.
I would add that this was probably due to prolonged detuning with much weather change in-between - and too deep of a detune. I doubt that only a few turns of the screw would cause the buzz, or any other real problems, so that isn't really my argument.
I would guess that the difference in detuning and not detuning on the longevity of a head is negligable, and that the added headache of having to turn the screws more every time you play isn't worth the possibility that you might have to mount a new head a few years before.

[bongo]

Now the quinto matched with that drum lost its skin at about 26 years, not from losing its sound, but because my hands had worn a hole through it along the bearing edge on one side. I made the mistake of always playing on the same spot, the other sides of the skin were still good.

Saludos Hermanos

Bongo

Man, you must have some ruff, and tuff hands. or that may have just been an inferior head leather. i have never heard of anyone wearing a whole through the skin from just playing. i have drums ive had for 10 years with the same head and played on the same spot every single time and the head has absolutly no wear. not saying its not possible. i just never heard of that happening to anyone before.


Oz

Oz,
Good day to you. Now you have another 16 years to go playing in the same spot and you may be amazed that a worn thin spot develops on the edge!

Mine I first noticed the skin surface was worn away and rough and when I held the skin up to the light I could see it was almost gone. It may have have been thinner there in the first place, but I know the surface wear was caused by my hands and many years of playing.

As to how rough / tough my hands are, well I do have callus, but my girlfriend does not complain. Come to think of it though I have not had her for 26 years, so I'll give it time.

[vinnieL]

Interesting debate sounds like the opinions vary just as much as every other "should I do this or that type question".

[109-1176549166]

...If longevity of the head is your reason for detuning, let's add another factor more along the lines of Bongo's analogy of the engine. The lugs. What happens to the screw and nut under repeated detunings? Isn't this an area of stress and wear? And what about the bearing edge and seating of the head against the edge?...

...I would guess that the difference in detuning and not detuning on the longevity of a head is negligable, and that the added headache of having to turn the screws more every time you play isn't worth the possibility that you might have to mount a new head a few years before.

Windhorse,

Re: lugs, you can always simply lubricate the screw and the nuts as often as needed, if you want to help extend their lives, just like frequently changing the oil of the engine (say, every 3 months) will significantly help extend the engine's life.

And it's not just the lugs and the heads (particularly, real skin) that those who regularly detune their drums are helping to preserve. More importantly, all things being equal, they're also helping to preserve the crispness and projection of the sound of the heads when they're tuned up again.

Even more importantly, you help maintain the roundness of the drums, especially those drums which are most tightly tuned, such as the quinto, requinto and the male bongo ("macho"). And by relieving the continued stress on the rims (both traditional and comfort style) and the points where the v-shaped ears are welded to the rim (for traditional rims only), you help maintain their structural integrity.

Particularly for drums with wood shells, not detuning could help cause or, worse, accelerate the premature cracking of the
stave(s).

I would grant that affecting the roundness of the drum is highly dependent on the material used for the shell. I'd speculate that fiberglass shells would be more resistant to getting out of round than wood shells. But, I'm not 100% sure.

Therefore, IMO, the difference between detuning (enough) and not detuning on the drum is not at all negligible. On the contrary, preserving the original integrity of the whole drum itself can be dependent on whether one regularly detunes it or not.

Then again, from a practical point of view, it really depends on how much you value your drums and how long you want to keep them. :;):



Edited By mjtuazon on 1184650686

[windhorse]

Even more importantly, you help maintain the roundness of the drums, especially those drums which are most tightly tuned, such as the quinto, requinto and the male bongo ("macho"). And by relieving the continued stress on the rims (both traditional and comfort style) and the points where the v-shaped ears are welded to the rim (for traditional rims only), you help maintain their structural integrity.

Particularly for drums with wood shells, not detuning could help cause or, worse, accelerate the premature cracking of the
stave(s).

So, you're saying that taking the stress off the head and adding that stress again and again in weather changing conditions when moisture is added to the bearing edge - more then less - as the head compresses on the bearing edge, then, decompresses on that edge, is better for the longevity of stave shape than keeping the head under tension?
I don't agree.
Too many variables changing by constantly adding, and taking away stress. Too much opportunity to screw up the tension slightly each time you tune it up. Also, the added inconsistancy of uneven moisture cloistering under the head against the bearing edge.
Everyone I know at home have drums with no alma. Non of them detune, and none of our drums are out of round. Even the old Gon Bops with splitting mahony. Many of the heads still sound good after 10-15 years.
We micro-tension tune the heads so that the head stays consistantly at the same overtone sound all around the circle near the bearing edge, so that there isn't an inconsistent pull at different points around the head.
I have seen drums out of round before, and my guess is that these were non-detuned drums as you suspect, but I think the cause wasn't non-detuning, but by inconsistent tension around the head.

[taikonoatama]

I have seen drums out of round before, and my guess is that these were non-detuned drums as you suspect, but I think the cause wasn't non-detuning, but by inconsistent tension around the head.

I don't know what to think at this point; both of you guys make a lot of sense.

Does anyone know a structural engineer?

David's observation in the quote above seems obvious now, but I never thought of it before - the stresses leading to a head going out of round aren't necessarily related directly to the constant high tension of a non-detuned head, but rather to inconsistent tuning around the head. There may be other stress factors involved, but this part makes total sense to me.

[bongosnotbombs]

I know several structural engineers, but they usually don't build things from cow skin

I can say what I can as an architect, obviously the rates of expansion and contraction are different for wood and skin, heat and humidity will cause them to change at different rates.

If the skin is tight all the time, the pressure on the wood will not be constant, however the exterior motion of the wood will be restricted in a distributed load from the tension applied from skin, this load will vary as tension across the skin varies.

Inward movement of the wood caused by the skin will be resisted by the compressive strength of wood, the wedge shape of the staves pushes back.

What keeps the wood from moving outward and causing splits is tension exerted inward by rings or bands and the glue which I believe resists movement laterally and outwardly.

A fully detuned head would do nothing to restrict outward expansion due to heat and moisture. A well made drum should be able to withstand inward pressure due to the stave design, however enough uneven pressure over time would distribute compression across the head which may be enough to cause some woods to deform.

Moisture mostly enters wood though the open grain, which would be the ends of the staves, less moisture gets into the top because the skin is there, thus most splitting occurs at the other end.

Wood has elastic properties, it will bend and the bounce back to its original shape, enough constant pressure over time could compress the cells of some woods and cause it to go into plastic range, where it does not return to its original state.

So the wood is going to move in two directions and the skin will also expand and contract and both will at different rates. In additon the forces exerted by the skin have the variable of tuning.

Probably the best decision is to keep the range small, a fully tightened head could contract quickly and rip or if it occurs often potentially exert strong uneven forces on the drum.

A fully detuned head could allow more moisture to enter the end of the staves and do nothing to restrict outward expansion.

In the case of congas it would seem the best solution may lie in moderation, slightly detune to mitigate any rapid contraction of the skin, but not to fully detune to maintain a moisture barrier and to limit outward expansion of the staves.

Just for posterity, I am an architect with some knowledge of woods and minor carpentry experience. However rates of expansion and contraction of Afro-Cuban percussion instruments was NOT part of my curriculum. Maybe they will add this class soon. :p



Edited By bongosnotbombs on 1184698338

[taikonoatama]

Great insight, Geordie, thanks.

And back to an earlier part of this discussion, I just want to point out how much local weather patterns/conditions figure into the whole detune/don't detune issue.

Here in the SF Bay Area in the summer the temperature can really drop at night, and you couple that with the fog rolling in from the ocean and that thick, cool, wet air can make your skins sound like cardboard in a hurry, so you really have to seriously crank up the skins, especially if you're outside at night. But, if you don't detune, especially, say, a rumba quinto, and the next day is clear, sunny and dry and 86 F (30 C) and you don't play/detune, that could get very ugly ...

[109-1176549166]

So, you're saying that taking the stress off the head and adding that stress again and again in weather changing conditions when moisture is added to the bearing edge - more then less - as the head compresses on the bearing edge, then, decompresses on that edge, is better for the longevity of stave shape than keeping the head under tension?
I don't agree.
Too many variables changing by constantly adding, and taking away stress. Too much opportunity to screw up the tension slightly each time you tune it up. Also, the added inconsistancy of uneven moisture cloistering under the head against the bearing edge...
...I have seen drums out of round before, and my guess is that these were non-detuned drums as you suspect, but I think the cause wasn't non-detuning, but by inconsistent tension around the head.

Windhorse,

I'll try to be as philosophically logical as possible. And I hope I succeed.

It just makes a lot more sense to me that a conga stands a greater risk of going out of round WITH TENSION (especially a lot of it) than NO TENSION (or little of it).

I totally agree with you that a conga stands an even greater risk of going out of round if it has uneven tension. But, notice that the common denominator between a conga that's never detuned and a conga that's unevenly tuned is the PRESENCE of tension rather than the ABSENCE of it or little tension.

Re: your point of "too many variables changing by constantly adding, and taking away stress" and "too much opportunity to screw up the tension slightly each time you tune it up", I'd like to point out the following:

(1) Stress poses a risk to the conga going out of round only at certain high tensions rather than lower tensions.

(2) Even though there may be more OPPORTUNITY (i.e., probability and not certainty) to screw up the tension slightly each time you tune it up, this is definitely NOT UNAVOIDABLE. Many of us have been taught or already know that we should always apply the same amount turns for each lug around the drum. And many of us, in fact, do practice this good habit.

Besides, even if you do "screw up the tension slightly each you tune it up", there's really nothing to worry about. Why? Because, for habitual detuners, the uneven tension on their drum should last, on the average, no more than merely 1 day. I, therefore, find it highly improbable that 1 day under an uneven tension condition would be sufficient time to cause the conga to go out of round.

So to reiterate, IMO, the bottom line is: There's obviously a much greater probability of a conga going out of round WITH TENSION rather than WITH NO TENSION at all. In addition, there's obviously an even greater probabilty of a conga going out of round under SUSTAINED TENSION (no detuning for long periods of time) rather than NO TENSION (detuned).

Mario Punchard himself, the maker of Isla drums, personally recommended to me that I should detune each tuning rod by about 2 turns if I'm not going to use your drum for a long time. My fellow Isla owner and friend, Yambu321 (Charlie), detunes COMPLETELY after each use. Lately, I've returned to following Yambu321's practice--again!

We can all argue the pros and cons of detuning or not detuning until we all turn "blue in the face". In the final analysis, it's all a personal preference or "religion" or "ritual", if you will. :;): And it depends greatly on our willingness and time to do it.

But, speaking only for myself, if it's better to be safe (partial detuning) than sorry (no detuning), then it's even better to be safest (complete detuning) than sorry (no detuning). I prize my Islas too much!

But, then again, if they were LP Aspires or the like, I'll probably stay always tuned (pun intended). :laugh:



Edited By mjtuazon on 1184726155

[bongo]

I'll jump in this fray once again.

So we all seem to agree that uneven tuning could be bad for the drum going out of round ....

So ... every time you detune and retune you are creating uneven tuning for the time it takes to go around the lugs. You can't tune all lugs equally at the same time, you have to put the shell under stress while you attempt to get the tension even all the way around the shell.

This in itself speaks to me of stress on the drum far greater than the stress on my brain trying to figure out the solution to this drum tension thing.

:;):



Edited By bongo on 1184720450

[109-1176549166]

So ... every time you detune and retune you are creating uneven tuning for the time it takes to go around the lugs. You can't tune all lugs equally at the same time, you have to put the shell under stress while you attempt to get the tension even all the way around the shell.

True. But, as I've said earlier, the time lapse under which the drum may be unevenly tuned every time you tune and detune is too momentary and insignificant, IMO, to cause the drum to go out of round.

What I'm agreeing to concerning uneven tuning is SUSTAINED uneven tuning staying on for days, weeks and even years.

I'd like to go back to my previous conclusion: To each his own. Go with what works for you. For me, I'm more sold on regular detuning rather than not detuning (unless you change the head or make minor/major repair[s] on your drum.).

It's your drum anyway. :;):



Edited By mjtuazon on 1184721856

[bongosnotbombs]

So ... every time you detune and retune you are creating uneven tuning for the time it takes to go around the lugs. You can't tune all lugs equally at the same time, you have to put the shell under stress while you attempt to get the tension even all the way around the shell.

In all fairness, the amount of time the tension is uneven is negligable, only a prolonged uneveness would be enough to overcome the elasticity of the wood.

Most woods are capable of withstanding large amounts of compression and tension. It is sustained loads over time that usually result in permanent deformation.



Edited By bongosnotbombs on 1184722893

[109-1176549166]

bongosnotbombs,

Thanks a lot! You took the words right out of my mouth! Precisely my point.



Edited By mjtuazon on 1184726010

[taikonoatama]

So to reiterate, IMO, the bottom line is: There's obviously a much greater probability of a conga going out of round WITH TENSION rather than WITH NO TENSION at all. In addition, there's obviously an even greater probabilty of a conga going out of round under SUSTAINED TENSION (no detuning for long periods of time) rather than NO TENSION (detuned).

Just a thought:

Is it possible that constant EVEN tension could actually help to keep a drum in round? Many woods have a tendency to move/warp/crack over the years, or to try to get back to their original shape if steambent - maybe this would help lock down the wood.

But even if that's the case, what's the effect of prolonged tension on the skin? mjtuazon's rubber band theory sounds good, but can we get some documentation to back it up?

I've always been a detune guy, but I'm enjoying the back and forth here ...

Edit: I somehow missed bongosnotbombs' last post. Still, one could ask: Would the deformation be neutralized by EVEN tension?

Most woods are capable of withstanding large amounts of compression and tension. It is sustained loads over time that usually result in permanent deformation.

Edited By taikonoatama on 1184727178

[taikonoatama]

We can all argue the pros and cons of detuning or not detuning until we all turn "blue in the face". In the final analysis, it's all a personal preference or "religion" or "ritual", if you will.

Although there is a certain habitual aspect to this, in the sense of each of us generally doing it a certain way, either tuning up/down before/after playing or not, I think most of us do it one way or the other just because it's the way we were taught at some point and not because we truly understand the science of what's really going on - we're working towards that understanding but are not really there yet. (I know, I know, everyone thinks they have the answer here, but as someone who is in the middle here - in spite of being a long time detuner - no one has conclusively proven their case yet.)

I have to think that in the final analysis the real answer lies in science, not just personal preference. Somebody we respected told us "blah blah blah" and we trusted their experience and wisdom and just did it. They probably just passed on what they'd heard and so on. I've heard that Mario of Isla has an engineering background - I'd be curious to hear the details of his take from a technical angle.

It's possible that the best option for the wood will be different than that for the skin - who knows. If that's the case, it'll become an even tougher call.

Let's figure this out!



Edited By taikonoatama on 1184729632