How to remove 1/2-3/4" strip from a bamboo pole

[BOB G]

LOOKING FOR A TOOL TO CUT A 1/2 OR 3/4 STRIP DOWN 5ft. PIECE OF STORE BOUGHT BAMBOO 1 1/2 --1 3/4 6ft.LENGTHS. FOR MY PROJECT I NEED MANY CUTS AND NEED A QUICKER WAY TO ACOMPLISH THIS TASK.I DONT NEED THE STRIPS.

[Mark Meckes]

Hi Bob,
Do you want to remove a strip out of the bamboo pole but keep the rest of the pole intact?
I can't find an example pic but this one will do, hehe...

http://www.bamboocraft.net/gallery/data/3035/1Mvc-183f-thumb.jpg
Cause of splitting (http://www.bamboocraft.net/gallery/showphoto.php?photo=665)

Here's a couple ways to do this...

1) After punching out the internode diaphragms with a steel rod (a length of rebar works good), use a cleaver and mallet to cut a single slot down the length of bamboo. Then repeat the process, slicing a strip off one or both sides of the split.

2) I've thought of a 2-bladed tool that could perform this task but it hasn't got past the idea stage...

2) Another method is to make the cut with a reciprocating jigsaw, using a blade that has been shortened so that it dosen't cut through the other side.
This method may take longer but can produce very accurate results and variations, like curves and zig-zags.

Mark

[paulineisaachsen]

LOOKING FOR A TOOL TO CUT A 1/2 OR 3/4 STRIP DOWN 5ft. PIECE OF STORE BOUGHT BAMBOO 1 1/2 --1 3/4 6ft.LENGTHS. FOR MY PROJECT I NEED MANY CUTS AND NEED A QUICKER WAY TO ACOMPLISH THIS TASK.I DONT NEED THE STRIPS.

Hi Bob

I have a circular saw with a 140mm diameter blade that has 72 tungsten carbide teeth. First you scribe the lines then follow with the saw. It does not stress the 'spine' as does a semi splitting method and it cuts like a dream.

[Mark Meckes]

Hi Pauline,
What type of circular saw do you use to cut the vertical slot in a bamboo pole. How large diameter and variety of bamboo do you do this to?

Here's also a new thread for general discussion about Types of circular saws, and their uses with bamboo. (http://www.bamboocraft.net/forums/showthread.php?t=1067)

Here, as mentioned in my previous post, is a photo of a slot cut down a piece of green harvested bamboo, using a reciprocating jig saw...
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)

This recently harvested Phyllostachys aurea (1 1/8", (3cm) diameter) pole was cut using a jigsaw, and a shortened blade.
The saw cut has closed up after making the cut, illustrating how bamboo grows in a state of inward tension, or compression?
It will gradually open up slightly as it dries.
This can be flame torched/heat tempered green or dry and the gap will widen up more, then when cooled, will stay basically in that shape.

Mark

[paulineisaachsen]

Hi Mark
Your P. aurea is what I would call 'pithy' i.e. immature. The fibres are free so the culm doesn't look that old. A cut could cause a green culm to close to a degree due to the weak lateral strength of the bamboo wall but I generally only find that with culms that are young. However, shrinkage, more prevalent in immature culms, is the most likely reason for gaps to close.
The machine I cut slots with is handheld. It is easier to control the cut particularly if the bamboo happens to have some variability we hadn't spotted and bamboo is notorious for that. It is not confined to green bamboo either, the only difference between the two types is the smell! It will cut any diameter bamboo down to say 25mm though I wouldn't go below 35mm, picture frame size. It will cut all species : Moso, henon, madake, kikkou, latiflorus, oldham, even aurea. I haven't tried it on textilis and the thin walled sp. but because the cut is so clean, not like a rasp, it should safely cut the larger diameter sp. of those. Build the adjustable channel with kickback safety measures in place.

[Mark Meckes]

Good observations Pauline!
Yes the scrap pole I tried this on was probably less then 2 years old.
However I do find the gap will close on a green but mature culm cut slot too, but the difference with using a circular saw is that the jigsaw blade I use is barely 1mm wide, and also the blade cuts through the nodal diaphragm as well.

I would imagine (never tried it) that when using a circular saw, that the blade depth wouldn't be set very deep, is that right?, Therefore if the diaphragm hasn't been sliced in half it would be less prone to close up or cause the blade to pinch, as the constant cutting width of the blade would slice off any closure during cutting (?). Where as the jigsaw blade cutting action is narrow both ways.

On the other hand `too dry' bamboo may pop right open upon cutting.

Maybe one of these days the notion that bamboo has some sort of inward tension when growing, fresh harvested or part dry and will be verified or dispelled..

Ongoing observations of a jigsaw cut green immature P. aurea culm..

http://www.bamboocraft.net/workshop/data/503/1050209PaureaJgsaw-50-thumb.jpg
Jig saw cut/drying immature Paurea culm (http://www.bamboocraft.net/workshop/showphoto.php?photo=1177)

http://www.bamboocraft.net/workshop/data/503/1050209PaureaJgsaw-51-thumb.jpg
Air drying naturally ( http://www.bamboocraft.net/workshop/showphoto.php?photo=1178), showing gradual discoloration.
Waxy exudate different to mature culm appearance.

http://www.bamboocraft.net/workshop/data/503/1050209PaureaJgsaw-52-thumb.jpg
Close up of curling upon drying (http://www.bamboocraft.net/workshop/showphoto.php?photo=1179), an indication of an immature culm, though curl will vary with different species etc.

Here's a different kinda split
http://www.bamboocraft.net/workshop/data/503/1050209JigsawspiralPhy-54-thumb.jpg
Jig saw spiral cut - P.aurea (http://www.bamboocraft.net/workshop/showphoto.php?photo=1180)

My first spiral cut experiment using a jig saw on some Phyllostachys aurea scraps.
With the two pieces on the right, I flame torched them to get them to expand more.
The one on the left dryed and expanded naturally opening about 7mm from an originally 3cm diameter piece.

[paulineisaachsen]

Hi Mark
Lost my latest reply somehow so here goes again. I feel very excited about your idea of spiral cutting the wall and leaving the nodal membrane intact. Great potential for some strength and safety in bathed or submersible applications. Even intermitent work. Great idea. Up there with the large sheath suspended by fishing line with a light underneath producing enough heat to turn it. (shared by the NZBS president Lynn Lang at this w/e's conference)
Yes the wider circular saw blade is adjustable and best cuts green bamboo when it has dried a month or more.

[Mark Meckes]

paulineisaachsen wrote
> Lost my latest reply somehow so here goes again.

Bummer when that happens! Sometimes the browser back button works to retrieve/copy/paste the lost text back into new reply...otherwise... :(

> I feel very excited about your idea of spiral cutting the wall and leaving the nodal membrane intact. Great potential for some strength ....

Me too! It has interesting `mechanical spring tension' as well, and other possibilities.
Will do some experimenting in a bamboo workshop coming up this coming weekend.


> Up there with the large sheath suspended by fishing line with a light underneath producing enough heat to turn it. (shared by the NZBS president Lynn Lang at this w/e's conference)

Was this a photo you posted as an attachment?
If so, you can edit your last post and re upload it.
... or post it as a New Thread in Things Bamboo Forum, then link to it here...
... or upload it into the Bamboo Arts and Craft Gallery (http://www.bamboocraft.net/gallery/index.php)

oh the choices!

Here's another variation of cutting strips down a length of bamboo...
http://www.bamboocraft.net/gallery/data/3019/1030820b-842-thumb.JPG
One piece bamboo sculptures (http://www.bamboocraft.net/gallery/showphoto.php?photo=294)

Bob G wrote
> LOOKING FOR A TOOL TO CUT A 1/2 OR 3/4 STRIP DOWN 5ft. PIECE OF STORE BOUGHT BAMBOO 1 1/2 --1 3/4 6ft.LENGTHS. FOR MY PROJECT I NEED MANY CUTS AND NEED A QUICKER WAY TO ACOMPLISH THIS TASK.I DONT NEED THE STRIPS

Hi Bob, what are you making with the bamboo? This will help me from going `off track' with the discussion. LOL

Mark