Advice and questions on making and fixing instruments
#38138
michi wrote:Since then, I've tried 24 hours on two occasions, and got bitten both times. It turns out that the skin isn't uniform but has some layered structure. The pigmentation is in the outermost layer. That layer seems to absorb more water and, while I was working those skins, started to separate and flake off. The net result were skins that had white patches where the outer layer had come off, surrounded by dark patches where the pigmentation was still intact.
That happened to me the first time I soaked a skin for a full day. A minutely thin layer came off in patches along with the hair. I thought for a minute I'd discovered a way to skip the shaving. No such luck - there's been no reocurrence.

No doubt there's point at which a skin submerged in water begins to deteriorate, but I haven't encountered it. Cellular damage has been mentioned, but I'd like to see sources cited. What I think is more likely to happen is that the skin begins to lose it's oils, fats, proteins, enzymes (just throwing these out - I don't know what goat skin contains). For this reason, I try never to soak a skin more than once. Just an intuition.
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By batadunbata
#38140
In response to Djembefeeling, I did put a very light treatment of karite on it and it sounds great, even better than before (as I mentioned, it's a very dry skin with little oil in it).
BUT I did it in a special way, to apply only a tiny amount:

-I dissolved about 1/16th tsp of karite into about 1/2 tsp tea tree oil, mixing them together completely.
-Then I dipped one finger into the mix, and rub this small amount between my hands, and then I rubbed the skin with my hands, all over until it feels like my hands are dry, and the mix is spread nicely.
-I did this about 6-8 times, until all the mix was gone.
-I then continued to rub the skin with my hands to polish it.

This method helps to thin/dilute the karite so it's not as thick, and to penetrate into the skin and the pigment, instead of simply coating the outside in a single layer, which could dampen the sound.

The tea tree oil almost entirely evaporates, leaving a light treatment of karite spread very thin. (and if any remains in the karite, it provides antimicrobial protection)
Last edited by batadunbata on Sun Aug 20, 2017 2:58 pm, edited 1 time in total.
#38144
O.k. guys, now I am interested! What is it that deteriorates the skin after long soaking?

The one instance that was worst in my case, the skin deteriorated so badly that there were some inch wide holes in it. I used to put my skins in a big tub in the garden that was full of rain water, often also had some leaves and stuff in it, just the stuff that gets into a tub in a garden. It wasn't any problem to soak the skins for 3-6 hours, but those 24 hours, yuck.

D.T., what kind of skins require 24 hours of soaking? Are you talking about goat? Because I had thick goat skin, but never required more than 5 hours of soaking.

If the cellular stucture of the skins does not crack, I don't know what really is there that feels so slimy and stinks so bad. My first time of mounting a dunun set it took me three days to get all three duns done. The first overnight skin was fine, the sangban after the second day was uncomfortable, but those two for the duns after three days of soaking were really nasty. They felt slimy and stank so bad that I had the biggest flies I saw in my whole life accompanying my work.

I think a skin can loose a bit of it's fat in water, the warmer the more. And you can see a little film of fat on the water after soaking a skin. But I doubt it's growing after soaking for a longer period of time. Fat and oil don't usually interact with water that much. And how can proteins be set free from the skin if cellular stucture doesn't crack? The proteins are within the cells.

The slimy feeling and the stink, I guess now this is because bacteria settled the skin in big numbers and start to diggest its surface. That would explain all of the experience we collectively had with oversoaking, also that it is useful to change the water once in a while and use clean water to beginn with. I remember the water being heavily chorinated in the US so that might help against bacteria.
That would also explain why prestretching does not result in any of those experiences.

In response to bata: interesting treatment. I learned not to put fat and oils onto a skin, rather play it regularly to put the fat of my hands onto it. When a skin has gotten that dry in the first place, I tend to think it's time has come to be replaced. That improves the sound more effectively, I'd guess.
#38149
I've editted the post, it was more like 1/16th tsp of karite, on a 10inch head (mini djembe)
It didn't "get dry", the goat had almost no fat on it, so the skin is bascially all collagen. It didn't ring in the same way the average skin does, hard to describe, but this has helped. I'll record it and post.

As for bacteria during the soaking, that makes sense. I would treat the water to prevent this. A couple drops of "Citricidal" (Grapefruit Seed Extract in glycerin) should be enough for a pan of water for skin to soak in (or a few drops for a bucket). The military use it to disinfect water.

But, as I mentioned, the pigment I used is antimicrobial, as are many natural dyes.

Another way to strengthen weak skins might be to soak them in protein, like soymilk, or milk, or dissolved protein powder (gluten, soy, etc). Afterward, you can rinse the excess off. This is done to paper or fabric to make dye stick more easily, and it adds strength.

Those first skins you showed DF, look like synthetic dye, which I agree does not look good, but natural dyes look better, and provide more depth of color/variation.
Some skins aren't pretty, and some don't match the shell they're on. White can look ugly IMO, depending on the shell and rope.

As for the biomimicry/tonewood chemicals, yes they are responsible for contributing to the sound to a large degree. A scientific experiment was done with African Blackwood, where they extracted the chemicals, soaked them into a plain wood, and it caused that wood to resonate well. (found by googling)
Whether this will transfer to skins is another question. It would require experimenting. It's possible that the way skins resonate would be impaired by these chemicals, not helped. But there are lots of different options, some are harder, some softer. I found the walnut pigment improved the sound of this skin a little, but as I said it was only a light treatment, and soaking would change it much more.
#38154
batadunbata wrote:It didn't "get dry", the goat had almost no fat on it
That's what I meant. English is my second language, so I don't always get it right. In German dry hair is the opposite of fat/greasy hair, so I thought I can say this.

You are trying to revolutionize the old ways of mounting djembes? Keep on searching and keep us informed ;)
#38156
michi wrote:If the water isn't clean and has been standing for a while, it'll be absolutely full of bacteria. I suspect that may have contributed to the skin getting damaged.
I think that's a distinct possibility.
djembefeeling wrote:D.T., what kind of skins require 24 hours of soaking? Are you talking about goat? Because I had thick goat skin, but never required more than 5 hours of soaking.
Why, thank you for asking. The skins on this 42" (corner to corner) powow drum took 3 days of soaking just to become workable, and I mean just workable. That's thick American bison.

Curiously, there was no discoloration of the water or smell, and I did not change it. Obviously skins differ, but i also suspect that the way skins are treated or not treated is a factor.

No goat skin I've handled required 24 hours of soaking, but my routine has become to put the skin in water the day before I plan to skin a djembe. Every now and then I'm not able to get to the skinning when planned and simply have to change the water and get to skinning the following day.

By he way, here's what that powow drum sounds like:



I think I'm officially a threadjacker. No I'm not!
batadunbata wrote:As for bacteria during the soaking[/u], that makes sense. I would treat the water to prevent this. A couple drops of "Citricidal" (Grapefruit Seed Extract in glycerin) should be enough for a pan of water for skin to soak in (or a few drops for a bucket). The military use it to disinfect water.
Have you actually tried this?
batadunbata wrote:Another way to strengthen weak skins might be to soak them in protein,[/u] like soymilk, or milk, or dissolved protein powder (gluten, soy, etc). Afterward, you can rinse the excess off. This is done to paper or fabric to make dye stick more easily, and it adds strength.
Interesting theory.
#38157
Don't worry DrTom, I enjoy conversational sidetracks and turns, but thanks.

That's got to be the biggest powow drum I've ever seen, what an incredible sound! I can imagine it calling people down from the hills, it's like thunder. Interesting that it took three days to soak the buffalo hide, well worth it though. I can hear it still deeply rumbling for seconds after he stops, beautiful. Wow.

No, I haven't tried Grapefruit Seed Extract for skins. But I'm sure it's antiobiotic enough, and in such small quantities, I doubt it would hurt a skin. The carrier, Glycerin, is used in skin products, and is water soluble so it rinses out. Worth a try if bacteria are a concern IMO.

Another protein that might work for soaking skins in to strengthen them is gelatin, since it's made of the same two amino acids as skin/collagen (arginine and isoproline). I'd make sure it was very dilute though, and rinse thoroughly at the end, otherwise it might work too well and make it stiff.
#38205
Thanks to your curiosity I dyed a skin for the first time. Actually, two in a row. I used Henna, light brown. The mixture got a little too wet, so it got under the gauge and blurred the result somewhat. But I am thrilled that it works, and relatively easy so. I have mixed feelings about the result, it's so cheesy and yet nice.
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Last edited by djembefeeling on Sun Aug 27, 2017 4:47 pm, edited 1 time in total.
#38208
I imagine that Henna would stain the skin pretty permanently, even if some does rub off initially.
And I imagine this style of art would look good even if it fades a little bit.

I'm glad you got inspired to be creative Djembefeeling, thanks for sharing the photos.
I like the watercolor effect, and the style you used. The lizards/geckos have a nice shape, sort of springy and yet round also, they look alive. Lively, yet relaxed. Playful but spiritual as well.

I understand what you mean about images being cheesy, but I like things both ways: simple/plain and with symbols/images. I prefer a mix in life, rather than everything being plain or everything being decorated. And I like images that are stylized and inspired by nature, like the ones you painted, because they connect us to our world with appreciation, which makes life more meaningful.

Geek fact: I looked up Henna, and it contains a chemical called Lawsone, which is a hydroxy napthaquinone, like the one in Black Walnut Hull, which is called Juglone.
#38211
I don't know how long it lasts. Henna is supposed to be permanent. I did play one of those drums for two hours this afternoon and it didn't effect the painting. My best guess is that it lasts a lifetime of a skin.

I ordered another gauge and tried this new one. It's still fresh, the greenish paste (smells like spinach, actually, and looks like it) will stay on the skin overnight and tomorrow I will scratch it off with a rasorblade.

Whoever wants to reproduce this can check for the ingredients here:

https://www.amazon.de/Marabu-028800004- ... +schablone

https://www.amazon.de/Viva-Decor-Gecko- ... gecko+viva

https://www.amazon.de/khadi-Naturproduk ... +hellbraun

https://www.amazon.de/Henna-Applikator- ... s%C3%A4tze
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