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Bamboozle
29th March 2005, 01:31 PM
Here's a review of a site that I had read, not quite in it's entirety before getting interested in all things Bamboo. It's a Shakuhachi making site. I copied a few paragraphs concerning curing Bamboo.

I admit it does say for the "adventurous." I'm not sure I qualify as being as adventurous as the fellow recommends. <g> I'll include the recommendation he made in the few next paragraphs as "TONGUE IN CHEEK!" for the time being, anyway.

French Fried BAMBOO

For the adventurous, there's an intriguing wood treatment which bypasses most of the traditional bamboo drying/treatment processes and that's to french-fry the green culm in hot non-catalyzed tung oil. Cut the culm and drill out the nodes. Heat a tube of oil to about 350 F. Introduce the green culm. When all boiling and other activity ceases cut the heat and allow the oil to cool with the culm submerged.

Here's what happens: All moisture is expelled as it's turned into steam and escapes as bubbles. All lignin in the wood is hardened as the oil temperature is above its hardening point. All the surface waxes will be melted and removed. During the cool-down period any air which was greatly expanded at 350 F. contracts and atmospheric pressure drives the oil into the wood. Wipe all excess oil from your culm and submit to the standard 3 month drying period.

The result will be bamboo which has had it's starches and sugars stabilized, all moisture removed and be thoroughly impregnated with hardened linoxyn. The wood will be markedly hardened and strengthened--being waterproof, dent proof, etc. The modulus of elasticity will drop considerably and the material will become even more rigid and 'musical'. The major component of a Stradivarius violin is the treated wood of the top plate. It's acoustical properties are what we recognize as exceptional sound. Once the culm has cured, craft a flute in your usual manner.

So, that's the (HIS) recommendation. It sounds cruel to a Bamboo lover I'm sure. I wouldn't try it on a prime quality root end section. I might try it on a piece of the upper section of the stalk. I don't know where I'd find a tube to use, but I guess I'll start looking for one. Maybe a piece of 4 inch steel pipe with a cap on each end and a wide slot cut down the length of the pipe and feet welded on to keep it from spilling the oil out. I'd also have to look for the oil that's recommended. The guy has definite ideas about which oil is good for Bamboo instruments.

It doesn't do much for decreasing the 3 month wait either, but at least he didn't say 3 years. I hope this doesn't get me labeled as an extremist, or as a complete Bamboozler. As I said, I present the recommendation as "TONGUE IN CHEEK."

The link to the site if anyone wants to read it in it's entirety is:

http://www.navaching.com/shaku/shakuindex.html

Mark Meckes
29th March 2005, 03:58 PM
heh heh, Nelson Zink had kindly given us permission to publish this article, see:
Shaku Design; Oiling Bamboo by Nelson Zink (http://www.bamboocraft.net/forums/showthread.php?t=931)
Good of you to address this topic again, here.
Nelson does bring up an interesting point of view, at least as far as flute making goes, re: using oils vs varnishes as a finish, which can be discussed in the above thread.
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Also check out Tatty's interesting article - Fried Bamboo Beads (http://www.bamboocraft.net/forums/showthread.php?t=985)
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Here's an article (link below) from the website of the Asian Network for Scientific Information ( http://www.ansinet.org/aboutansi.php):

Strength and Durability of Bamboo Treated Through an Oil-curing Process (www.ansinet.org/fulltext/jbs/jbs45658-663.pdf) (pdf file - 232kb)
by Razak Wahab, Hashim W. Samsi, Mahmud Sudin and Janshah Moktar, University Malaysia, Sabah, Forest Research Institute, Kuala Lumpur, Malaysia
Abstract:
Investigations on the strength and performance of oil-cured bamboo, Gigantochloa scortechinii, in a 12 months ground contact. Tests show that the bamboo experienced some reduction in their strength properties and greatly enhanced the durability against biodegradation agents.
Oil-curing process:
The oil-curing process of the bamboo was done using an electrical oil-curing machine. Palm oil was used as the heating medium as it is organic in nature, easily available and has high boiling point. The palm oil was first heated up to a temperature of 60°C. Then the bamboo samples were submerged in the heated oil by placing them in a metallic cage. Bamboo samples were taken out at 140, 180 and 220°C intervals after 30, 60 and 90 min of exposure....

Bamboozle
29th March 2005, 11:24 PM
HA,

It looks like wherever I go you've already been! Long Ago.

Mark Meckes
30th March 2005, 06:09 PM
Re: French Fried BAMBOO
Me thinks this process may have been first tried out in a fast food restaurant, possibly by a starving artist/musican trying to make ends meet between gigs... :)

Deep frying long pieces, such as a full size flute has it's challanges, in finding a suitably sized reseptacle...
My only experience in flute making is this flute (http://www.bamboocraft.net/forums/showthread.php?t=548) which is suitably sized for experimentation ...

Mark

Bamboozle
6th April 2005, 05:35 PM
Well,

My flutes aren't so big so far. The longest one is about 30" - 762mm. A small grease drum could fry several pieces this size all at once, saving a lot of time over treating one piece at the time in a 4" - 100mm section of steel pipe. A grease container that holds 120 pounds of automotive grease is a lot smaller than a 55 gallon drum. I haven't checked to find the price of the oil recommended for the "French Fry" method.

I'm getting information on speed curing Bamboo from a rod makers group. I'll share that when the research and experimentation is complete.

Angel
6th April 2005, 07:36 PM
Anybody knows any scientific research about gas torch heating proccess?