Repairing Splits in Bamboo Flutes

[Waya Atli]

Is there any way to repair splits that occur in a bamboo flute?

[Mark Meckes]

Hi Waya,
Would you have a picture you can upload into a post here, showing the crack in the flute?
Repairs are possible but it depends on which part of the flute, and to what extent the crack has developed.
Is the split continuing to grow? Is the crack widening?
Is this a recent split or did it happen some time ago?
Does it split appear to be stabilized?

Mark

[Waya Atli]

The split just happened. It does not seem to be getting any wider and it is in the side of the flute. The split does not appear to go all the way through.

[Mark Meckes]

Well, if the crack recently began to form then there's a degree of unpredictability as to whether it will split more.
The drier winter humdity may be the culprit.

Try wrapping the flute in a lightly dampened cloth, put it a plastic bag for a day or two and see if the crack closes up.

Here's a link about binding your flute:
Tai Hei Shakuhachi - Options for binding (http://shakuhachi.com/Q-Binding.html)

Mark

[Angel]

Dear Waya and people,
First, apologize my language, I'm not a native so hope you underestand.

There are two interesting concepts to discuss: one, what to do if bamboo already cracked, and the other, how to prevent it.


I have some experience with flutes and cracks. Either if the flute is new or old, if a crack appears is very difficult to determine if it will continue or not. As Mark said, is important
to determine the axial position -if are toneholes on its line or not. Anyway, I use different glues depending on the wideness of the crack, and if is necesary to force
the material to return to its original position or not.

The crack you describe seems to have no contact with the air column -at least yet!
There are different cyanoacrylate glues grades of viscosity that are used for fine, hairline cracks.
First, press the flute tangentially to the crack -that means, ON the crack- and see if it tends to close or not. (fingers pressure might give you an idea, if you have strong fingers! if not, use a C clamp) Then, press in other directions gently and see the crack's
reaction. If it still open with the pressure, use a thicker glue, if it closes, use a thin one.
Fill the crack with glue and rapidly bind the zone the closer to the end of the flute is possible. For long cracks, an extra binding should be of help.
The best for binding is waxed nylon (called here Lupolino, don't know in English) Mark Mortimer uses this.

I use to use 2 component epoxy glue instead of ciano. The best here is to slightly heat the crack with a hot air gun, and use a slow drying glue.
The heat melt the glue -like water, specially if the glue has no much aerosil- and makes it to go well inside the crack.
This procedure gives you more time to do the binding properly, but is somehow sticky. Don't clean the flute till the binding has been done.

The best to clean epoxy glue is isopropilic alcohol (sorry for the translation if not correct) with a cloth that don't let cotton hairs. A tissue paper might work.

Ah! About the bag, I heard that enclosing the flute (or whatever cracked bamboo) in a nylon bag with orange peels make the crack to close. Never tried such a thing!

Angel Sampedro del Rio

PD: del Rio= of the river or from the river

[Bamboofount]

Angel

I'm near you here at Porto Alegre- Rio Grande do Sul - Brazil.
I have the same problem you have with english but... here we go!!!
I have not experience with flutes, but I have the same problem when my bamboos split, when they are cutted waiting to be used in my water fountains - www.bamboofount.com.br. I used to fix them mixing glue (PVA quick dry)for wood, with very fine bamboo powder, to keep the same visual of the surface of the original bamboo.
The P.aurea too split near the deformed nodes and it is necessary to do a "make up" whem I use them in others crafts ( you can see at the gallery:bamboo&copper laddle). This is a critical situation because the laddles are used in many situations that begin at the kitchen and finish pendig years in a wall like a decoration piece.
My experience with epoxy glue to fix bamboo (working with water) is bad - they split a new time beside the surface glued. I believe that the epoxy glue do not have flexibility, like the bamboo fibers have, they work with different coefficient of expansion, but our products have many differences.
It is better to listen more experient peoples from flutes.
Bye,
Ene

[TribalWind]

Angel is right on the money , use CA-gue(cyanoacrylate,,aka"super glue" ).polyurethane glue (gorilla glue) also works good but dont use too much.
waxed nylon is also sold as " synthetic sinew" sinew being that strong translucent covering over muscles etc i believe...Tandy leather company sells it,cheap and lasts forever... another option for temporarily binding is strap-clamps/Pipe-clamps the metal strap type with a slotted hex nut. those work great if you ever step on one of your flutes!
(dont ask me how i know this)

wow..i'm digging all this flute talk around here lately! even if i cant hold a flame to some of the dudes who responded already ; :p

[Mark Meckes]

It's amazing how bamboo is able to hold itself upright when it grows.
One thing that surprised me when I made my first longditudal cut down a bamboo pole was that the cut closed up. It didn't open up like I thought it would.
This recently harvested Phyllostachys aurea (1 1/8", (3cm) diameter) pole was cut using a jigsaw, with a shortened blade.
http://www.bamboocraft.net/workshop/data/503/thumbs/1050125-23aPaurea.JPG
Phyllostachys aurea -single cut with a jigsaw (http://www.bamboocraft.net/workshop/showphoto.php?photo=1035)

Notice how the saw cut has closed up after making the cut, illustrating how bamboo grows in a state of inward tension.
It will gradually open up slightly as it dries.

It is possible to `capture', or preserve this state of inward tension, though only through certain procedures during drying.
If the bamboo has been improperly dried, if the inner substance has become brittle and lost it's holding power, then there will be increased possibilities of cracking and splitting in it's intermediate `afterlife'.

Anyone who has not had the pleasure of working with bamboo from it's raw, green harvested state may not know that the bamboo purchased or acquired will-nilly is less then ideal. One may think it's the character of the bamboo to split and crack, whereas in reality the bamboo may long ago have `died', begun to fall apart, and is on it's way to bamboo heaven.
The only way to hold the bamboo back would be to bind, bound and strap the bamboo down to our earthly pleasures.
http://www.bamboocraft.net/workshop/data/2/thumbs/1Mvc-183f.jpg
Cause of Splitting (http://www.bamboocraft.net/workshop/showphoto.php?photo=665[/url)

HAH HAH HAHAHHA!
Bamboo gets the last laugh!

Mark

[Angel]

Dear Ene and group,

Sorry for my long delay -much work with bamboo here!

Good to hear from you in Porto Alegre, muito legal!!
I was there in a artisanal fair for some years arround 1995-97, when the fair has been held in the Usina do Gasometro and in the Cais do Porto.
Muitos saudades!

I agree with you that epoxi glues don't work well in contact of water or intense humidity. I had talked about that with an expert on glues, and told me that although nominally epoxis aren't afected by humidity, they actually are, and also they cant follow the movements that materials do with that.
Anyway, for the values of humidity present in flutes, they are OK, even close to the mouthole.
I replaced epoxi glues by Titebond II in permanent glued pieces of my bamboo saxes. Titebond II is an aliphatic, D3 grade glue, similar in application as white vinyl glue for woods, but incredibly superior either in strenght and in resistance of humidity. The same man told me that since normal glue build only vertical chains of molecules, this glue build some horizontal ones that gives the strength to humidity and allows to follow more the expansion of material.
But is not enough for permanent water works.
Titebond III seems to be since supports 4 hours of boiling in water.

Angel

[Angel]

Ene:

to avoid -or almost - cracks in Ph aurea distorted nodes, heat it with a propane torch WHEN IS well GREEN, and then let it to dry.

[Mark Meckes]

Angel wrote
"... The same man told me that since normal glue build only vertical chains of molecules, this glue build some horizontal ones that gives the strength to humidity and allows to follow more the expansion of material.
But is not enough for permanent water works.
Titebond III seems to be since supports 4 hours of boiling in water."

Very interesting info about glue, Angel!

I wonder what the molecular structure looks like, of the `natural glue' that grows in bamboo, and what are the changes during it's living-life through to it's after-life?

I'm sure there must be many things we can still learn from natures ways!

Mark

[TallTree]

(Merged with above thread)

I have a peice of root end yellow bamboo that I purchased from Frank's Cane & Rattan supply (thanks to the lead from Henry Lee in an earlier post), that apparently has a hairline crack running 2/3 of its length (approx. 49" overall).

I can simply chalk it up to the fate, use it for practicing working with bamboo or repair it. The crack is long, but not deep. A few years ago a friend of mine had a rainstick that had a crack in it as well. It was repaired with wood putty, which worked, but didn't look too good. Is there anything (ie. filler. glue, etc) that I could use to repair this, retain a decent look and won't adversely affect the sound quality (its for a flute)?

Tall Tree

[sound world]

At the end of the day,I think you might have to 'chalk it up to Fate'.
There are ways you can attempt a repair-various combinations of glue/putty/fire/water/oil etc etc have all been used,but in my experience (plenty,far too much with cracked bamboo :( )it ultimately either looks bad or the crack gets bigger.With rootstock at least the chances are that the crack wont go right through because as a rule the wall thickness is much greater.
Be grateful that you live in a climate where bamboo splitting is a rarity! Here in the UK I've had entire bales of bamboo-50 or more 12 foot lengths of 3" diameter dried bamboo-completely split to pieces-almost useless to an instrument-maker!:rolleyes:

[Mark Meckes]

Anyone want to start a New Thread in the line of ...
- 'What to do with my cracked bamboo? ...in reference to what musical items could be made, the list might be wide spread and lengthy.
---------

Most cracks are repairable, unless your split looks like this...
http://www.bamboocraft.net/workshop/data/502/thumbs/SplitPaurea020102-123.JPG (http://www.bamboocraft.net/workshop/showphoto.php?photo=1503)

The puckered split of this Phyllostachys aurea (left outside in the elements to weather) is an indication that it was a younger culm when harvested.

---------

The crack in this 2.75"/7cm dia Moso Phyllostachys edulis -aka- P. pubescens hasn't gone all the way through the inner culm wall.

http://www.bamboocraft.net/workshop/data/502/thumbs/SplitPedulis060324-567.jpg (http://www.bamboocraft.net/workshop/showphoto.php?photo=1504)

A crack will always be wider at the outer circulmference ;)
A 1+mm layer of the inner culm wall is made of a substance very similar to that of a hard gourd, and is resilient to cracking, ie, separating apart in a straight line until stress from opposing tensions pull it apart.

The composition of a culm wall varies with species and part of culm.

Example...
Phyllostachys vivax at mid height of culm. Known as a thinner walled bamboo, and more prone to cracking.
http://www.bamboocraft.net/bamboo/data/539/thumbs/1PvivaxM16-MGA050227-814.jpg (http://www.bamboocraft.net/bamboo/showphoto.php?photo=966)

------