how to use bamboo as belly- please help (have no idea how to do it)

[Gaur]

Ok dragonman if you tried it and based on your experience you can do so.  For me that would defeat the whole reason to make such a bow.  I still wouldn't say it would be benificial to do so and you would want to get it right in you stack

[james parker]

sure- natural bamboo lams,and bamboo flooring can be used as the core,, but performance will be lost,,, maybe not a dog per say to shoot, but   very noticable differences compared to to any hardwood  core lams.. as far as breaking through the belly,a significant drop in poundage and cast will be apparent,,almost instantly,,, but a lot has to do with thickness of boo belly lam, how much carbonizing of belly lam,  there is a large difference ,in just light heating the belly compaired to all out black  full carbonizing of the lam,, also  quick flash carbonizing compaired to  slow heating or long time smoking  of bamboo  will be very different  too.  in my test and experience the more temper , the more wiggle room you have , if you do break through the belly,, it is still easier to Pre- factor in the tiller in the lams ,,than to scrape for a targeted poundage,, of course that just my assessment,,, I'm no pro,, i just build a bow

[Badger]

  I have to admit that the intact bamboo belly bows impress me more than almost anything else. I would not recomend them for new builders for sure.

[james parker]

 

[dragonman]

yes of course its better not to sand the belly...I  dont  touch the nodes or the rind unless I have to... I am saying.if it is necessary it can be carefully done..... if it means the diference between a shooting bow or one that is going in the wood burner, then scraping the belly is an option....but aim for symmetry and exact taper measured with a vernier......this was my first advice

.(.even the old japanese bowers used a basic wooden vernier to measure the taper)

James Parker has made more of these than me and knows more...I would  follow his advice now he has showed up...

[Gaur]

I asked James how many of these style bows he has made over the years.  He said according to his ledger he is at 1872 bamboo belly bows in 25 years.  That's a lot of bows. 

[james parker]

yes of course its better not to sand the belly...I  dont  touch the nodes or the rind unless I have to... I am saying.if it is necessary it can be carefully done..... if it means the diference between a shooting bow or one that is going in the wood burner, then scraping the belly is an option....but aim for symmetry and exact taper measured with a vernier......this was my first advice

                                    what dragonman said,,   i agree completley

[bubby]

So james the question i have is do you prefer flash carbonizing or a slower method?

[Pat B]

I've watched James flash temper a boo belly strip    and it would scare the heck out of you to watch and you'd wonder how that charred belly strip could withstand the compression stresses of the bow...but it does...but also, this ain't James' first rodeo. He has probably built more bows of all styles than most of us put together. So, listen to what James says and take it as gospel.
...and actually James, you are a pro. 

[arachnid]

I'm glad this topic got alot involved. I just don't get one thing- if I'm using ipe as a core, why not make a bamboo backed ipe short bow (60", as planned with the bamboo belly)? What's the benefit in making a bamboo backed bamboo (with ipe core) bow?

[bubby]

Well originally the topic WASabout how to use a boo belly not boo backed epe wasn't it😉

[arachnid]

Well originally the topic WASabout how to use a boo belly not boo backed epe wasn't it😉

Yeah... That right.... But I thought of making a bbb without a core. Now that I understand that without one the bow will have poor cast, I wonder why not make a BBI instead? Seem way simpler...

[bubby]

It is certainly easier, but if you don't push yourself you stagnate, imo

[Gaur]

Cuz bamboo belly bows look cool  and perform great.  I have one from James that has ipe as a core and two other Osage lams.  Most of his designs have three lams.

But bamboo backed ipe and bamboo backed Osage are great as well.

[james parker]

  what is flash carbonizing?   the  least amount of time spent to temper a subject (bamboo belly lam), but at the same time get a thorough  heating through the rind down to the near other side of the strip without total burn out or burn through or total annhialation of the lam.... whew that was a mouthfull.. anyway - it takes a lot of practice and ruination of good bamboo,, i suggest practice on scraps a lot first..  now you have  to take in account the thicknesses of the boo backing strip as well as the core wood  stack, if any,,, a single one pc core can be used- but with great difficulties when inducing reflex or recurve of the limbs, also, springback will be more if built on a form of any kind,, rope and wedges  takes care of this problem.. target poundage is figured into the build before hand ( the stack), tillering can be achieved with and or spot limb heating or knee tillering but too much of either one can induce set  in one particular area more than another,,, takes a lot of practice also.. R and D is time consnuming and expensive... try boo backed bows first ,work the bugs out ,then try adding the belly strip to an existing bow and then work the bugs out from there..