# Bamboo



## Barry747 (Jun 16, 2011)

I know that Stick did his PhD thesis on Bamboo in a post last year but I thought this article might be of interest. Personally, i'm not interested in using it for any of my projects but it is an interesting material. When I think of grass I think of seeding, watering, fertilizing, more watering and then mowing it down, then doing it all over again, and again, and again, but, I digress. 

In 1970, when I was young and stupid, as opposed to being old and stupid, I took an R & R in Hong Kong. Of the many things that impressed me, which I still remember vividly, was the extent of the scaffolding around buildings made entirely of Bamboo. Very large pieces of Bamboo, but, still, bamboo. All I had ever seen in my short life up until then was steel. When I was in school I took a materials course where we took various materials, iron, various types of steel, aluminum, concrete and wood and subjected them to tension, compression and shear forces until they failed. It was neat to watch a steel bar neck down and break under tension and to see how much force it took to crush concrete but I was surprised how much force it took to break a wooden beam. Back then, I thought Bamboo was a type of wood and drawing on my limited knowledge I didn't know how strong grass was.

For general construction, I can understand how valuable Bamboo is considering how quickly it grows. I've also seen here in Pennsylvania, not an ideal climate for Bamboo, not only how quickly it grows but how quickly it can spread. Great for commercial growers, for homeowners, not so much. At least it isn't ivy or kudzu family.


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## Stick486 (Jan 4, 2013)

thesis heh..


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## DesertRatTom (Jul 3, 2012)

I recently discovered some bamboo in the middle layers of big box 3/4 ply. It was not a solid piece, but about 1/8th wide strips. When I tried to cut a dado, this layer splintered so badly I had to discard it. You are correct about the spreading. The spreading happens because the roots act as runners, and like crabgrass, new plants sprout from the runners. If you don't contain the planting below ground, the bamboo will take over as much acreage as it can. 

I've seen bamboo used for scaffolding, but never understood how they join it together so it doesn't wobble or collapse.


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## Cherryville Chuck (Sep 28, 2010)

I have a bamboo hardwood floor in part of my house. 10% tougher than oak. That's probably one of those 5 or 6 commercial species. I've been looking at some Tonkin bamboo being sold for arrow shafting. The ad says "nature's version of carbon fiber shafts" and I think that's not far from the truth since both have longitudinal fiber held together with resins. Bamboo is also used in one or two of the laminations in some bows (archery i.e.). The bows with bamboo in them tend to be a little snappier than with other wooden lams. 

I read about the scaffolding years ago. They tried to get the construction workers to use regular scaffolding because it's quicker to erect but they didn't trust it and refused to work on it. I'm guessing they lash it together just like we learned to do in the boy scouts. From an engineering point of view it is stronger than steel for its weight.


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## TWheels (May 26, 2006)

Bamboo is indeed a very fast growing, very strong grass. However, all fibers are parallel with little cross linking between strands, unlike wood. Hence end grain problems and cross grain issues are much worse with bamboo, hence the issues @DesertRatTom described with cutting dados in plywood with bamboo layers. Commercial bamboo "lumber" is essentially bamboo fibers randomly oriented in a matrix of glue. Bamboo can also have a rather high silica content, which would cause havoc with any cutting tool such as router bits. I obtained samples that were part of what led me to cause @Stick486 to dust off his Ph.D dissertation. The samples are very attractive; I may dig them out and show photographs of them. If I need to replace the flooring in my house (or build a new house) I am very likely to use bamboo flooring.

@DesertRatTom how did you try to cut the dados, table saw, router, etc?


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## OPG3 (Jan 9, 2011)

History tells us that Bamboo was also used in the first versions of reinforced concrete. The segmental rings act as "deformations" in rebar. I think that sometimes something such as Bamboo is advantageous opposed to steel rebar due to its quick conformance to heat transfer. Sitting in the sun, rebar can get so hot that it prevents proper cement hydration in areas where that bond is so critical. 

Otis Guillebeau from Auburn, Georgia


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## Barry747 (Jun 16, 2011)

I mentioned in my original posting that I was in Hong Kong on R & R. I took the attached pictures in 1970. Addressing Charles' comment, as best as I remember, and it was a long time ago, the bamboo was lashed together. I honestly don't know if they used any other type of fastening device or system in addition. I tried enlarging the first picture until it lost too much detail and it appears that they used lashes. I reduced all of the pictures in size for posting. If anyone wants the original, in case they have better software to view them, let me know and i'll send them to you.


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## Stick486 (Jan 4, 2013)

Why people love it: Currently riding a wave of popularity, bamboo is fast-growing and eco-friendly. It says, “I love old barns, owls, and other all-natural, outdoorsy stuff.”

Why it’s overrated: This isn’t real wood, and bamboo is technically not a “tree,” but is in the Poaceae (grass) family. Hundreds of small strips of bamboo material are machined and glued together, making quasi-boards. Sustainable? Yes. Natural? Hardly.

Try this instead: Real wood. It has character, uniqueness (two different boards actually look… different), and isn’t a series of tiny processed shards held together with glue.

Common Name(s): Bamboo

Scientific Name: Hundreds of species among dozens of genera from the Poaceae (grass) family (Many timber-producing bamboos are from the Phyllostachys and Bambusa genera)

Distribution: Most timber-producing bamboos are from south Asia

Tree Size: Some of the largest bamboos can be up to 50-100 ft (15-30 m) tall, with a 3-6 in (10-20 cm) diameter

Average Dried Weight: 31 lbs/ft3 (500 kg/m3) to 53 lbs/ft3 (850 kg/m3)

Specific Gravity (Basic, 12% MC): .38 to .64, .50 to .85

Janka Hardness: 1,410 lbf (6,270 N) to 1,610 lbf (7,170 N)

Modulus of Rupture: 11,020 lbf/in2 (76.0 MPa) to 24,450 lbf/in2 (168.6 MPa)

Elastic Modulus: 2,610,000 lbf/in2 (18.00 GPa) to 2,900,000 lbf/in2 (20.00 GPa)

Crushing Strength: 8,990 lbf/in2 (62.0 MPa) to 13,490 lbf/in2 (93.0 MPa)

Shrinkageiameter: 10-16%, Wall Thickness: 15-17%

Color/Appearance: Generally a uniform and pale yellow to almost white. Live bamboo that has been left standing too long frequently develops fungal decay, discoloring the wood with brown or black streaks and patches.

Grain/Texture: Being a monocot in the grass family, bamboo does not have any sapwood/heartwood or growth rings. Texture is very uniform, and ranges from medium to fine depending on density. Bamboo that has been split and processed into lumber will have intermittent variations in the fiber at each node on the stem.

Endgrain: Resembles the endgrain of palm—another monocot. No data is available to distinguish between bamboo species, but bamboo can usually be distinguished from wood and palms by the hollow stem, pale color, and the lack of rays or visible pores.

Rot Resistance: Bamboo used in exterior conditions is perishable, and will deteriorate in a matter of years. This is also paralleled in the short natural life cycle of bamboo, where many species quickly reach full maturity after only two or three years, and are subsequently attacked by decay mold and fungi, typically collapsing only a few years later. Bamboo is also susceptible to insect attacks such as powder-post beetles, termites, and marine-borers.

Workability: By woodworking standards, bamboo can be different. It is not necessarily difficult to work with, but depending on the species, it may require some special care. Bamboo fibers tend to split and pull out when being cross-cut, (applying masking tape across the cut line beforehand is recommended to prevent this sort of tearout). Also, bamboo is very high in silica—from .5% to 4.0%, found almost entirely in the outermost layers of the stem—so care must be taken when processing lumber. Carbide cutters are strongly recommended, and surface sanding is suggested instead of thickness planing with steel cutters, both for longevity of cutting edges, and quality of the finished surface. Bamboo glues, stains, and finishes well. When turning giant bamboo species, tools dull quickly, and endgrain tearout is common, but tearout tends to be very shallow, and the endgrain sands nearly as easily as the facegrain, and an overall smooth finish can be achieved with minimal effort.

Odor: Bamboo has a unique, earthy smell while being worked.

Allergies/Toxicity: Although severe reactions are quite uncommon, bamboo has been reported to cause skin irritation. It’s unclear whether the bamboo itself actually causes the irritation, or if it is simply due to the decay fungi commonly present in the material. See the articles Wood Allergies and Toxicity and Wood Dust Safety for more information.

Pricing/Availability: Bamboo is typically available in three forms: in hollow turning-blank sizes from giant bamboo species; in glued-up boards (flooring) and sheets made from many smaller strips; and in paper-backed veneer. Although bamboo is a very abundant natural resource, and prices for raw material tend to be low, (it is often called the “poor-man’s timber” throughout bamboo’s natural range), prices can be much higher for processed and glued-up imported products: often exceeding the cost of domestic hardwoods.

Sustainability: This wood species is not listed in the CITES Appendices or on the IUCN Red List of Threatened Species.

Common Uses: Veneer, paper, flooring, fishing rods, ladders, scaffolding, musical instruments (flutes/woodwinds/chimes), furniture, window blinds, carving, turned items, and small novelty items.

Comments: Bamboo is one of the most unique plants on earth. Unlike trees, bamboo grows initially at full width, with no tapering or horizontal growth. Some species can grow up to three feet a day! After just one year, bamboo reaches its full height, and in subsequent years, the stem (called the “culm”) continues to harden. The strength of the bamboo continues to increase for the next two to four years; most species of bamboo are considered fully mature in just two to three years. After this time, fungus and mold begin to cover the outside of the culm, eventually working its way into the interior, weakening the plant over several years before it eventually collapses from decay. For this reason, there is a window of time when it is considered best to harvest bamboo for optimum strength and hardness.

Bamboo is known to have a high shrinkage rate when initially being dried, amounting to 10-16% in culm diameter and 15-17% in overall wall thickness. Bamboo tends to shrink more towards the outer wall than at the interior: for this reason, surface checks can develop on the outside of the culm if it is dried too rapidly. However, despite the high shrinkage rates for bamboo, once it has adjusted to equilibrium moisture content, it is somewhat stable in use.

Although many prefer the aesthetics of bamboo for its unique, down-to-earth, Asian-flair, the real story on bamboo lies in its mechanical properties. Although it is hard to typify a group of over one thousand different species into a single set of mechanical values, on the whole, bamboo possess some of the best stiffness/strength characteristics, and strength-to-weight ratios of any woody material on the planet.

But the difficulty in qualifying bamboo’s strength lies not only in the abundance of species, but also in the lack of standardized testing: a complicating factor is that bamboo itself tends to be harder and stronger toward the outside of the culm, gradually getting softer and weaker toward the center. In some testing, certain species of bamboo at certain areas of the culm have exhibited stiffness (m.o.e.) and bending (m.o.r.) values far exceeding that of any hardwood. The only “weakness” of bamboo is simply inconsistency: with so many different species, and so many ways to cut and process bamboo, it is hard to be assured of the mechanical characteristics of any given bamboo product.


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## DesertRatTom (Jul 3, 2012)

More than I need to know about the stuff.


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## JFPNCM (Dec 13, 2009)

Marketers are now pushing clothing made from bamboo. Initially it feels very soft and cushy so I invested in a pair of socks. Didn't last 2 months.


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## Herb Stoops (Aug 28, 2012)

JFPNCM said:


> Marketers are now pushing clothing made from bamboo. Initially it feels very soft and cushy so I invested in a pair of socks. Didn't last 2 months.


Did you forget to mow it?
Herb


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## JFPNCM (Dec 13, 2009)

Herb Stoops said:


> Did you forget to mow it?
> Herb


Nope, forgot to cut my toe nails. :surprise:


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## DaninVan (Jan 1, 2012)

Bamboo is broken into two types; runners and clumpers. Most of the really striking varieties are in the 'runner' category, and that's where the horror stories come from. The 'clumpers' are generally smaller and very well behaved in the landscaping scenario.
I have three varieties of clumper and all are model citizens.
I get mine from these guys...
Canada's Bamboo World | Bamboo Plants


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## Knothead47 (Feb 10, 2010)

Bamboo can also be used for water purification I am told. FWIW, the best bamboo for bamboo fishing rods is the Tonkin bamboo from China.


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## Herb Stoops (Aug 28, 2012)

DaninVan said:


> Bamboo is broken into two types; runners and clumpers. Most of the really striking varieties are in the 'runner' category, and that's where the horror stories come from. The 'clumpers' are generally smaller and very well behaved in the landscaping scenario.
> I have three varieties of clumper and all are model citizens.
> I get mine from these guys...
> Canada's Bamboo World | Bamboo Plants


There is Bamboo, and there is Bamboo, didn't know there were so many different varieties, Dan. Thanks for posting.
Herb


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## DaninVan (Jan 1, 2012)

Used to be a nightclub in Vancouver called Big Bamboo...


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## DaninVan (Jan 1, 2012)

Damn! I just found a new variety that I _need_... 
Borinda papyrifera 2"culms? Fast growing?! 
"Hello, Bamboo World; I need to place an order."


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## JFPNCM (Dec 13, 2009)

DaninVan said:


> Used to be a nightclub in Vancouver called Big Bamboo...


Sounds like the voice of experience. >


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## Bodger96 (Mar 18, 2014)

There is a company up here that is called Just Bamboo and they make eyeglass frames, lacrosse sticks, baseball bats, bicycle frames etc.

Regards Bob


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