Author Topic: Bamboo Node Distance and Core question  (Read 2113 times)

0 Members and 1 Guest are viewing this topic.

Offline arachnid

  • Member
  • Posts: 517
Bamboo Node Distance and Core question
« on: January 19, 2015, 04:28:55 pm »
Hi Guys.

I`m about to finish flattening my bamboo backnig strip to 1/8" thickness (and WOW, it looks SO thin!
the crown is 1/8" thick but the edges are paper thin! Am I going the right way?)
Anyways, since it`s the first time I`m using bamboo I`d like to make no mistakes. I`m planning
a 45#@26" BBI pyramid with perry reflex. So...

Do I have do keep the distance from the tip to the first node equal on both limbs? In one limb the distance
is 18" and in the other it`s about 1 1/2" less. Is it critical?

Second- I have a 3mm thick lam of african walnut that I`d like to use as a core.
Will core help keep the reflex better?
Does 3mm to much for a core?

Any info and other suggestions would be welcome. It`s been long since I`ve built a bow for myself and I realy like the idea
of making a tri-lam.

Thanks

Dor

Offline bubby

  • Member
  • Posts: 11,054
Re: Bamboo Node Distance and Core question
« Reply #1 on: January 19, 2015, 04:39:05 pm »
here's a boo backed bow i'm finishing up, on one tip the node is 11' from the tip the other 4 1/2' just how it worked out for the length, I try and get a node pretty close to the center of the bow
failure is an option, everyone fails, it's how you handle it that matters.
The few the proud the 27🏹

Offline SteveT.

  • Member
  • Posts: 72
Re: Bamboo Node Distance and Core question
« Reply #2 on: January 19, 2015, 09:07:06 pm »

Dor: It is natural for the spacing of bamboo nodes to get farther apart as you go higher on the culm. So placing a node in the handle section of the bow is a good idea, because it improves the limb harmonics. Don't worry about the location of nodes near the tips, as you can't make them equi-distance anyways. Taking the thickness of the bamboo backing to knife edge along the length of the backing, is what I do. Photo shows the backing and core and the belly lam of osage for this bow.If you trace the taper of your ipe core onto the backing and cut it out, then you can flatten the backing more and it will be knife edge from fade to tip. Makes it look nicer and more professional, even tho. it is an extra step. Please show us the bow when it's all glued up, and I wish you success.

Offline arachnid

  • Member
  • Posts: 517
Re: Bamboo Node Distance and Core question
« Reply #3 on: January 20, 2015, 10:13:25 am »
Great looking bow Steve!
The core looks realy thick. I'm planing to use the 3mm thick walnut as a core and start with a 15/32" thick ipe belly and then go on from there. All is going to ha a pyramid taper from 1 1/4" fade to 3/8" tip.

Offline bushboy

  • Member
  • Posts: 2,256
Re: Bamboo Node Distance and Core question
« Reply #4 on: January 20, 2015, 06:50:12 pm »
If your building a recurve,i like to try to keep the nodes out of the apex of the bend.
Some like motorboats,I like kayaks,some like guns,I like bows,but not the wheelie type.