Adventures with Bamboo

[riarcher]

Recently recieved a bale from Fl.
Seems some bend almost effortlessly while other just simply don't want to hear it.
Arrr, power of the internet! Plugged in "How to bend Bamboo".
Hard finding good(?) info on it, but there is some anyways.
Sure, some simply bends easier / better than other,, but it's mostly due to variety / type  of  Boo.
Had to go thru a lot to gain bits and pieces.

One guy was using a big torch, and what appeared to be a damp rag. He bent what looked like a 2" piece into a sharp "U".

Another somehow(?) said he filled it with sand (sand looked damp) and he bent it up pretty good.

Another was saying, green (as in fresh?) bends easiest.

Didn't notice at first, but eventually one thing stood out. Water! Either from fresh cut, rag, or damp sand.
(Bolt of lightening here) It hit me! They are actually steaming it!

Went and grabbed a piece that I broke because it refused to bend and tried bending another section,, stopped before it broke, but no bend.

Wrapped the same area in hot, damp towels and let it sit for a couple hours. Tried it again and it bent, not like soft butter, but it did bend fairly easy with the heat.

Hmmm, one experiment does not make a finding conclusive at all.
So I went and pulled some from the bale. Had to notice some really felt different than some other. The color is different shade some, and the darker seemd a but heavier. (More fresh? Still holding more water?)
Anyways, I've got about 2 doz. soaking in a hot tub for the night. I'll see tomorrow if soaking helps bending or not.

Hindsight - Figured someone here must of already tried this? But I don't see any mention.
I'm guessing something bad may happen? Any input on this? 

PS; I very quickly moved it away from the heater. However, Winters in New England are rather dry and may be adding to the problem(?).

[Swamp Bow]

What is your heat source?  I'm using a simple propane plumbers torch, but I added a piece of copper tubing as an extender so I can keep a low flame, but still focus the heat.  Since I can't see the flame, I adjust by sound.  I've found that it is best to put some heat into an area then come off of the heat, and then go back onto it.  I just bounce back and forth after the initial heating.  It seems like the heat needs time to work or absorb and if I just leave it over the flame I go from not bending to over cooked and broken in the blink of an eye.  Ive also found that it is really important to sand down the nodes so the diameter matches the surrounding area or they will just break and not bend because I put too much heat into them.  I've also learned that it won't bend until it is ready, and if I apply a lot of pressure/heat it will just break.  It really does not take much heat or pressure, the heat just needs time to get deeper into the material, and I often get better bends with less pressure than with more.  I still get still breaks, but it is usually because I get impatient, or want to bend it "just a little more".

Swamp

[aero86]

I haven't had any problems bending mine.  Tried all sorts of sizes.  The nodes do take more time of course.  Id recommend though if u have a big bent node to. Straighten most of it out first before sanding, in case u get a little outta hand.  But like I've said get a 2 setting heat gun and put it on low and just make a few adjustments and set it aside and move to another while that one cools a bit

[riarcher]

Aero -
Watched your vid more than once today! Grrrrrrrrrrr!
You, in vid,, under 7 minutes. and it was that close.
Me - 7 min. and I'm on the 2nd (mild) bend! and a lot more to go.
I did have a few that bent just as nicely /quickly as your's in the vid with about the same # of bends.
Some,,, Just don't want to. Hot enough to burn. Hot enough so I don't want to hold it. About 4 minutes on one bend. But no bend. No steam, and on those that don't bend,,, it doesn't get shiny first like the ones that do bend nicely.

BUT - The wife,, she goes to work tomorrow. I'll steal the hairdryer! 
I've tried a candle, kerosene lantern w & w/o chimney so far. Was thinking elect. stove. But, I couldn't concentrate the heat well for the noles. And access with a 4' anything is tricky (and the wife? She'd screem!  (no sense of adventure that gal  )


SWAMP - " if I just leave it over the flame I go from not bending to over cooked and broken in the blink of an eye" Hmmmm, sounds familiar!

" Ive also found that it is really important to sand down the nodes so the diameter matches the surr" Hmmmmmm. again.

Thanks guys. I'll try all those suggestion in the morning (and the soakers).
Wondering if I've been concentrating the heat in too small of an area? I'm only heating(?) a 1" area in length mostly. Rolling it, but not spreading it out. The heat gun and torch I need to assume heats a longer section by far than I am. Hmmmm. (and so were the vidios of the Chinamen) Hmmmm.
I was even tempted to slip them in the wife's oven for "pre-heat"(?).  HMMMMMMMM.

[aero86]

When I use my heat gun its usually an area a little under 2 inches long.  Id have to have a piece of the tough stuff to see what's going on

[jamie]

get yourself a 1 lb coffee can or something similar. punch some holes in the lower side of the can to let air in and use charcoal as a heat source. you can hold the boo over it and itll work fine. i prefer to make a lid with holes in it and drill a hole on either side of the can for the arrow to slide through. a couple passes through that furnace will heat that boo right up. its very similar to the furnace used by the korean bow makers.

[Tom Leemans]

I just use my heat gun held with a quick clamp so it points up.

[Swamp Bow]

While I will occasionally just roll the boo over the flame for a split second to keep the piece hot, but I tend to move it length wise.  I've had problems with just rolling it.  The problem with this stuff is there is no one right way, you just gotta figure out what works for you.  Like you, I bought a 500 culm bale, so I have plenty to screw up and not stress about it.

BTW no one has mentioned this, but I would be concerned about adding moisture, it take a long time to come back out again.  That 35# spined arrow may become an 80#+ monster in a year or two.  I admit I've never done that though.

Jaimie:  Ive thought about that, good to know it works.

Swamp

[riarcher]

today's test results -
Decided to splurge, went and fetched a heat gun.
Bending the Boo as recieved didn't improve much. Maybe a little, not enough.
Filed down the noles on a few. First straightend like a breeze. Broke the next 2 stuborn ones!
Tried the ones I soaked,, no difference at all from what I could see.

Okay, out of a random group of 10,, 3-4 bend like limp spegetti with modest heat.
Maybe 2-3 will bend if I really lean on them. I can heat them to the cows come home and it doesn't seem to matter. Others breab at the nole or I quit because I feel them splitting / ripping.

I'm not selecting what looks to be the better ones. Thinking I should get a technique down first(?).
The ones that give me the most trouble have very large(?) noles (as compared to the easily bent ones).

You can probably tell I'm getting frustrated with these and need to give them a break (pun intended) for a spell. I've run out of ideas on what I'm doing wrong.

I'll try and post a pix of what I'm working with.

Ones on the bottom I was sucessful at bending relatively clos. still needs more though.

[mullet]

 Looks like some good Tonkin. Are you trying to bend the nodes or in between first? Chris Cade sits down and watches TV and straightens me a dozen during an hour TV show when I'm there. He uses an alcohol lantern like they sell in Three Rivers. I've done the same with a candle. It doesn't take much heat. And I think if you use too much you temper the bend out and make it break easy.

[Swamp Bow]

Once you get the aggravation level down, try this:

Sand down your node (or not, see below).  You can really sand those suckers well past the actual nodes.  I've seen one of David Knights arrow shafts, and he sands the whole shaft, so you don't need to worry.  Take a really good look at the node.  I've found that the actual node usually does not need that much work.  Often it is the area right by the node on either side.  What confuses the eye it that there may be a bend right after the node that can be in the opposite direction of the overall bend in the area between that node and the next one.  So if you have a gentle sweep downward between two nodes you may have a short S curve right by the nodes.  Now heat the area you need to straighten until it is hotter than you want to touch, remove from the heat, let it cool to where you can uncomfortably touch it (give or take depending how nerve dead your fingers are), then reheat, and remove again.  Now apply gentle pressure in the opposite direction of the bend, just let it do it's thing slowly, after a few seconds you can put it over the heat again under pressure.  Move the shaft sideways back and forth in the heat and inch or so to either side of the area you are working.  BTW that is that way I usually heat anywhere in the process, you can even "move" the heat zone by moving more in one direction as you shift back and forth which comes in handy for straightening large areas.  Remove after a second or so.  Repeat as needed.  Once the area is moving, you can keep tweeking it for a surprisingly long time even after it it well cooler than you think is too cool (feels like tweeking a POC shaft).  You just can't make really tight bends unless it is hot.  Go on to work another node.  Then come back and work the other side of this node.  Make sure the side you worked before is nice and set (cool).  I've read some people use a ice cold damp towel/rag, I just work another node or shaft till it is ready.   Back to sanding.  Once you line up both sides of a node, you can often just sand it straight.  So sometimes it is best to wait to sand until you straighten.  You also keep it in mind as you straighten (stop as soon as you can).  Another thing about sanding, use it to your advantage for heating.  If you need to move an area of the shaft in front of a node and don't want to move the other side of the node, leave the node unsanded (tougher to bend that way) until you have done so.  If you have a bend that goes through the whole node, sand the node flat to the surrounding area.  You may even sand down the area next to the node if you have a "bulge" in the shaft.  Each shaft is different, and I treat each different.  Just take a good hard look at each shaft and make sure you do what it needs, not what you think it should need (that is my biggest mistake).  Once you get better at figuring out how much heat and how fast you can apply it, you will speed up and break less shafts.

That is the way I straighten, and I'm still new to it.  Lots of different ways to do it.  I think it is like flintnapping, you just have to break a bunch of stuff before you "get" it.  I still get frustrated sometime as well, I just have to "walk away" a bit and come back to it.  My torch is hooked up to a hose which goes to a 20# tank.  I just clamp the torch head into my vise.  I'll walk into the shop work a few shafts on a regular basis and then toss them into my "mostly straight" pile.  Sometimes I do one, sometimes i do ten, it just depends how it goes that day. 

Hope it helps.
Swamp

Swamp

[Josh]

... I just use a can of Sterno cooking fuel on a little table in front of me while I watch TV.  I think the trick is just don't try to straighten them out perfectly in one pass.  I usually do in between the nodes in one pass, then the nodes, then I roll the arrowshaft on the floor and see where the problem areas are, then make another pass.  I usually do this 2 or 3 or sometimes even 4 or 5 times before I am satisfied with the straightness.  I just think you are trying too hard to get them too straight too soon myself... 

[riarcher]

Perhaps I've been expecting too much?



Left -tried to fix what looked like off-set.
Middle - another attempt to fix off-set and to align at node.
Right - To my eye (at the time) this looked terrible. From outside it was ugly and had problems. Once split and looking at the inside it looks as though it would of been good.

Definitely learned not to scorch / burn the Boo! 
It appears that while the outside is off looking, the inside can actually be much better.

I'm expecting to get these as straight looking as I was doing POC's. Now I'm thinking maybe I expect too much?
As for bending, some just don't seem to want to. BUT, when I hand selected the greener, straighter, more uniformed ones they came right in with the heat gun on low.
I also think with the candle / lantern I was using too much heat and expecting them to move easier than I should of. Essentially I may have been tempering them before bending?
Sent a bunch out yesterday but had to break a little off an end to fit the box. I noticed some snapped right off like a dry twig, others would bend and have a hard time getting it to separate (stringy?) and all sorts of deviations in between.
The ones that failed to separate (relatively) easy I noticed looked fresher, greener, and more of a waxed surface to them. Separated some and found they bent nicely with marginal heating. Was grabbing the ugliest for learning and saving the better for when I knew something.  May have been a bad idea. 
Guess I'm learning,, but what a PIA these things are!!!
Have a few more to rough straighten. Then I'm going to try a finish straighten with the idea of not trying too much to align the nodes, just get the shaft straight from end to end even with some bumps, lumps, and wavering. (Average straightness?)
I've a ton of questions, but one hurtle at a time for now. 
Started out trying to hurry a doz. to try. I'm over that now. So much BS involved so far I'll be taking pains to make them look like it was worth the effort. (No short changing  )

Thanks everyone for ideas. Many were used / tried and helped.
Areo - thanks for putting up with the PMed questions! 

Gary

[Swamp Bow]

Yup, they have a certain PIA factor.    The (half)shaft all the way to the right, I'd move the top to section to the right a little, the bottom to the left to "split" the difference and then sand the node smooth.  One of the things that got me over and over was that my brain kept saying that the dam wall in the node has to be perpendicular to the shaft.  It doesn't, and life has been so much easier since I beat that concept out of myself.  This stuff can be made very very straight, just look at David Knights stuff, look like they have been extruded.

Swamp

[Parnell]

I've only been using a heat gun, myself, but I do straighten them gradually over a few sessions, like you Josh.  Jackcrafty did a build a long and showed some good tools to help the job out straightening them. 

Hey Riarcher - where are you at in RI?  I went to the University and used to haunt Narragansett.  I loved the spearfishing!  Got me some awesome stripers bobbing around Pt. Judith, the wreck off Narragansett beach, right off the rocks infront of the Coast Guard House...lots of places.  What a beautiful coastline...