bamboo advice needed on first bow

[irbthbow]

Trying to get started on my first bow. I have researched a lot, but feel I'm just scratching the surface.

I decided I liked the reflex deflex laminated bow to start with. After looking and reading and watching several builds, I came up with a layout for a hickory bow with a bamboo back. I plotted out a 1" graph background at work and made a tillering tree. I bought some titebond 3 and necessary sandpaper, clamps, etc. hoping to get started a.s.a.p.. The missing link is the bamboo.

One of the hurdles is bow making material. I was trying to avoid buying a kit for some reason. I have access to some hickory, but have to cut and split it which wouldn't get me started for a while. I ventured to a hardwood supplier this weekend and bought some 4/4 hickory, 4/4 hard maple and 4/4 red oak. I have a nice piece of rough sawn black walnut. I planned to use the maple and walnut for the handle.

So, I harvested some green bamboo about 2 1/2" dia. on a friends farm. There were some standing dead and some on the ground, but they weren't but about 1 1/2" dia. (not sure of species, but volunteer in eastern NC). My question is how to treat this bamboo for curing. I took one 7-8 ft. piece and split it in quarters. I removed the interior rind at the rings and laid it flat on the floor with boards on top to flatten. I didn't cut any of the others because of uncertainty. Today I read about curing it standing on end for 3-4 months...ouch. I also read about heat tempering it but could not find a good tutorial on the process. Now I have some bamboo, but just not sure how to prep it for use. The dry I found seemed very hard and brittle. I can go back and get some more dry if necessary.

I understand how to plane it to flatten the inside, but I don't see how it could be flattened enough on the outside to be used on a 1 1/2" wide surface. Can someone explain how to handle this for use on a bow.

I may have to end up purchasing some, or change up my plans for my first bow.

[darwin]

typically you only flatten the inside of the stalk if you are using the bamboo for backing because removing the nodes significantly weakens the fibers on the outside of the stalk which are need for tension

If this is your first bow you might have bitten off more than you can chew (or not) i tried to do almost the exact same bow as the one you are describing for my first bow and it broke on me (you might have better luck or more skill than me)

imo you should start with a plane old straight board bow and practice tillering

all the same i wish you good luck and hope everything works out for you

[irbthbow]

Yeah,sorry for the confusion, I didn't mean plane the outside. I didn't know if you could heat it and clamp it down to flatten it before planing the inside.  With the radius that's on the bamboo, if I planed the inside flat it would only be about an inch or so wide and would be shaped like a duck call wedge.

[darwin]

once bamboo is dry it can be hard to bend but its worth a try id try on scrap first if you have any

[markinengland]

A reflex deflex bow is challenging to tiller, even if you have experience.

My advice would be to try a reflexed bow or two before trying this much more challenging bow type.

[DarkSoul]

I, too, think you might haven bitten off more than you can chew. You are considering a rather complicated bow, even for a moderately advanced bowyer, let alone a novice. I don't know your level of wood working skills, but I would highly advice you to start off simple. No glue, no bending with clamps, no wood drying. Once you know how to handle the tools and how to tiller a bow, you can work your way up.

Nonetheless I'll try to answer some of you questions - and more.

- The maple, oak and hickory you bought...what does it look like? How many knots? What's the grain like? The advantage is that this wood will most likely be dry and thus ready to work with. In contrast to your bamboo, which is still green. You can start building a board bow without laminations tomorrow, and shoot it within two days.
- Hickory is very strong in tension, and often does not need a backing. In fact, a bamboo backing can overpower the belly and the gluing process often adds more hassle to the construction, which adds another complexity to the process.
- A bamboo pole of 2½" diameter is rather narrow. It can make a narrow backing strip, but you indeed will not get a slat of 1½" wide. However, the backing can be narrower than the (hickory) belly. Still, I personally think that such a narrow pole of bamboo will be difficult to work with.
- The 'bow design' picture is a bit too technical for my liking. Making a wooden bow doesn't work with pre-determined numbers. Of course you need some figure so you know where to start, but avoid a mathematical approach.
- You made a tiller tree; good! many novice bowyers start building bows without one. A good tiller tree makes tillering sooo much easier. Do you also intend to build a form for the glue-up? Your bow design plan looks to be designed for a form? You said you bought clamps, but how many? You need a lot of clamps for a bow, OR you could use elastic rubber bands such as bike inner tubes to wrap a bow. If you decide to laminate a bow, you need to figure out how to shape the lams, how to glue them together, how to press them together and how to hold them into shape while the glue sets. A dry-run is indispensable here.
- What drawweight and drawlength are you aiming for?

Don't over complicate things. Keep it simple stupid, and let the shavings fly to keep you motivated!

[warpath]

I agree with Darksoul. I specialize in bamboo backed bows and it took me a long time to get to that point because bamboo is extremely unpredictable! If you've got some good straight grained hickory, I would start out with a simple selfbow to pratice tillering and proper limb and fade tapers. If you insist on making this as your first bow though, i'll happily send you a piece of tonkin bamboo that I've already dried and tempered. It's 2" wide and just needs to be planed flat on the pulp side. just pay for shipping and it's yours.

   Again though, try a simple board bow first to hone your skills. That's the best way to start out.

       G

[irbthbow]

O.K., I guess the build alongs made me think....I can do that. Perhaps I should rethink that. It may be a little too ambitious.

I was hoping for a 28" draw somewhere around the 45-50 lb range. The drawing was for a form, or the actual shape I was looking for. I have a blow up of the handle too. I'm a draftsman by trade and it's my nature to know the desired dimensions for something before starting a build.

I have (2) 9" x 13/16 x 72" hickory boards. I have not ripped for width yet. I can attach a pic later. They are straight grained, but to get down to one growth ring for the back, I may lose some thickness. Can you cross a grain or two on the back without it busting? From what I've seen most people use staves for selfbows and start with the outer ring or just under the sapwood for the back.
I may be able to get a couple of growth rings out and use the hickory as a back and the oak or walnut as the belly....just thinking.

Warpath... I would love to get that bamboo, pm me if you don't mind. I spotted another grove of bamboo yesterday and plan to get a better look today and contact the landowner.

Still, if anyone knows or can tell me if you can "flatten" bamboo, or if it can be ripped before curing, or how to temper it, I would appreciate it (I haven't searched you tube yet.). At least I can prep some for a winter project, or for trade.

[Pat B]

My suggestion would be for you to start out by learning proper tillering on a simple wood bow design before you attempt one of the most difficult style bows to tiller (IMO). Boo backed R/D bows are very cool and sexy but not a style to learn on. I've been building wood bows for 25 years and still have trouble with R/D style bows. It looks to me that you are setting yourself up for failure which leads to frustration and is no way(IMO) to learn how to build wood bows.
  You have some of the best wood bowyers in the world at your finger tips and they are willing to share their years experience with you and all you have to do is ask.

[darwin]

i would pick one of those boards with good grain give it a pyramid profile and just tiller it out aiming for your draw weight but do not be overly upset if you miss the target its more important to learn how to get a good tiller

you can call it a practice bow

[Eric Krewson]

Raw bamboo often cups into a U shape if it has been cut into strips while green and then dried.

I have found the best way to dry bamboo is to use a rake or hoe handle to nock the nodes out of the inside of the trunk to allow airflow, stand the trunk in a corner for a couple of months, then cut into backing strips. Your backing strips will need another month or so drying time before you use them on a bow. 

[irbthbow]

Took the advice and started a board bow last night with hickory. Laid it out 67" tip to tip, 66" notch to notch. 3/4" wide x 3/8 thick to start at the tips. 1 1/2" at the midlimb, 1 3/4" x 3/4" at the fade...2" fade and 4" x 1" handle. I cut the shape and the profile out and checked floor tiller and almost no bend. I used the bandsaw to take the belly down 25 deg from the edge of the back and finally got a little bend. Put it on the tiller tree with a long string and pulled on it 40-50 times until I got up to 40 lbs. of pressure on the limbs with not a lot of bend....I'd say about 6-8" of brace, so I'm just starting. I needed to quit until tonight so I went ahead and cut 1/2" piece of black walnut and another of hickory and glued up a handle (TB3, no pic of that).

My concerns so far are once I ripped the board, there was a definite bow to it about a 1' from one end. That means relaxed the bow will have more bend towards one end. Not sure if I should try to correct that somehow. The pic of it on the tree is relaxed to show the natural bow.The other is I had a few grain runouts on the opposite limb. I read on one instructional that this was o.k., but I'm guessing if I'm gonna have a failure it will be there.

I had focused so much on a laminated bow I'm questioning the shaping of the belly on this one as I work towards a goal weight and draw. I guess a "D" shape from what I've seen.

[darwin]

i wouldnt worry about that bend once you start tillering your goal should be to get both limbs bending evenly this will be easier if the bend is relfexed but if not then, oh well since its your first bow it will probably have some set anyways just go slow and read through all the tillering advice you can before you get started because thats really the heart of bow making and will either make or break your bow, literally

[bubby]

make a tillering gizmo, top of the how to page, it will help a ton to get a good tiller, Bub

[irbthbow]

I took this pic. early yesterday. I shaped a simple handle a little and got it back up to tiller. After this pic and about 3 hrs of work I reduced the width of the limbs twice on the belt sander and took quite a bit off the belly with a rasp to get a lot more bend than is seen here. Forgot to take a pic of that. Getting a lot closer to target weight and draw.
I shortened the string I have to get closer to measuring weight and length of pull accurately, but it has quite a bit of stretch. I was planning on ordering some B55 today to make a string and wasn't sure of a good serving material and tool. Any suggestions? Best place to buy (fast shipping and good price)?