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Guest
22nd March 2001, 03:04 AM
Dear Mark: I have read your comments on the problems of splitting and other matters. I also beleive in individualism in the culms.
Here specially there are major problems in cutting down the Dendrocalamus Asper and the Guadua Angustifolia.
At the moment of cutting there are enourmous pressures on the two parts in which it is being cut. Ther weight(of 20 to 25 meters) just by itself is enough to cause perhaps in the future splitting. The bending moment at the cutting edges are also of a very high magnitude.
We are starting to copy some of the big logging machines features on a very small scale, and we will see if it works.

cordially
Derick

Mark Meckes
22nd March 2001, 05:17 AM
Hello Derick,
You have brought up a very important issue.
- When harvesting poles, it is very important to keep the culm upright, and to not let it lean during cutting or it will pinch the saw blade, and may cause a split at the base, or cause a fracture that will split later when this section is put to use.
- It is also important when cutting a long pole into sections, that support is given to the cut-off piece to prevent splitting.

The bottom section of a culm is highly valued for craft work, because of its' thickness, strength, and special character of the shortened internodes.
The lower portion of a culm has a higher potential market
value, so it is worth giving the extra effort when harvesting.
Also, a culm that is not scarred through handling has much greater value...concrete floors, asphalt, gravel, rocks, sharp metal racks, careless use of knives and saws can reduce top grade bamboo to mediocre poles.

One reason I like to use a coping saw for harvesting in open groves (eg Phyllostachys sp)of up to 2 1/2 inches, is that the blade is only 2 - 3 mm (1/8-3/16th inch) wide. This allows me to hold the culm very upright and the blade does not get pinched.
The only problem that occurs is that my knuckles are brushing against the ground when I cut, and one knuckle in particular gets abrazed from a surface rhizome, if I'm not extra careful.
I don't like to wear a glove on my right(cutting) hand because I have less of a grip on the saw handle. But I have found that if I put a fabric bandaid on that knuckle BEFORE I start cutting, it doesn't get scarred.
For larger culms, I use a razor-toothed hand saw.

If I was doing the hand cutting, I would be able to keep several people busy - one to prop up the pole to prevent splitting, who would then pass the pole to others who would take the pole out of the grove to be sorted, graded and trimmed, stacked or bundled.
Whether working alone, or as a team, this harvesting work needs to be done very procedurely.

When harvesting from clumping bamboos, it is much harder to get right down to the base of the culm to make the cut.

Recently, more reciprocating power saws have been coming out on the market that are powered with rechargeable battery-packs.
I would be very interested if anyone has tried one that has good power, and with a long-lasting battery pack.

~ Mark

Guest
22nd March 2001, 08:19 AM
Dear Mark: Thank you for your comments . We are using gasoline chain saws to cut down the clumps. It is very difficult to straighten out the clumps because of their weight (approx one ton)and thicknesses(7 to 8 inches diameter at the base). Furthermore we have had a couple of snake bitten péople so matters are not very simple.
But we are gradually removing the older clumps and the newer ones are not as heavy or thick.and not as close
together.

Regards
Derick

bambooda
23rd March 2001, 03:24 AM
Hello All,
One thing you might try to prevent the saw blade from
binding is to make the first cut about 1/3-1/2 the way through, then come from the other side and make the second cut to meet the first. This works with most any kind of saw - including a chainsaw - and makes a cut with less
splintering than a single cut all the way through.
One tool that I've seen used successfully here in Hawaii is a weedeater with a toothed disc cutting blade. The disc has a series of chain saw teeth attached to the perimeter. The advantage is you can cut close to the ground without
bending over. I think the limit is cutting culms of 2" diam. or a bit more. In regards to the big culms (5" diam. +) that are inside the clump and are more or less held upright by surrounding culms, I make a cut almost all the way through from opposite sides, then above this cut I cut two V shaped notches that are also opposite each other (not too deep).
I then tie a 3/4" nylon rope tightly in the V shaped notches and attach the other end to my truck. The rope should be long enough so there's enough slack to get a running start. Back the truck up - then blast off and a culm of 80-90 pounds intertwinded in the clump will come flying out!
A word of caution: depending on how far inside the clump
the culm is, one must make the first cut high enough so it doesn't come straight down and imbed the butt end into the clump - the results are pretty hair raising!
There are also things like path of least resistance, ideal terminal velocity, obstructions in the path of truck, etc. that only comes with experience.

-Cal

ddhort
29th May 2006, 06:23 PM
Recently, more reciprocating power saws have been coming out on the market that are powered with rechargeable battery-packs.
I would be very interested if anyone has tried one that has good power, and with a long-lasting battery pack.

~ Mark

Mark,
We are using the Ryobi reciprocating saw with great success. Although the basic saw is relatively inexpensive, (around $50) you need to purchase the battery and charger which doubles the expense, plus a spare batttery.
In addition, I'm using a six inch 14TPI blade and slicing through canes of 5-6 years old (Oldhami) roughly 3-4 inch diameter. The saw has greatly reduced time and effort even in tight places.

Best,
David