Yumi

[ichiban]

hey all i am looking for GOOD refrences in regard to construction and demensions for the longest form of the japanese yumi, using the traditional draw i would draw about 38"

[Eric Krewson]

Jaap Koppedrayer has a video out on yumi bow construction. His web site wasn't working last time I checked. I will look up a contact number for him.

Here he is building a yumi bow at the Hill shoot this year.

[Jesse Peltan]

What in the world is he doing with that bow?

[rainman]

Using wedges and cordage as his clamp.  By putting the wedges in at certain places on the bow he creates reflex or deflex.

Dan Raney

[Pat B]

James Parker(Huntworthy Productions) did a demo with the wedge and cord clamping at the Tenn Classic in early May. Pretty neet how simple it is and how well it works.

[Jesse Peltan]

That's pretty cool. I will have to try that some time.

[ichiban]

ahh i see now how the claping works, yea i looked up jaap but hes site was down, i understod the principal for the wedge method but if i use that then i will want to make fish glue  and grow boo for shafts etc so i may go with a caul (for the first few anyway)

[Eric Krewson]

Jaap's e-mail kkoppedr@cyg.net and here is the phone number (912)586-2763 He lives near Odum, Georgia

[Jeremy]

I have Jaap's video, or at least did until I loaned it out... I'll have to check to see if it made it back or not.

For constructing the traditional long yumi I don't think I'd want to try it any other way than with the wedge method.  He says he's made glass bows like that as well.

If I remember right, the core of these bows is traditionally very complex, consisting of 3-5 vertically laminated bamboo slats with hardwood edging (mulberry I think).  The core was then tapered and faced and backed with raw boo slats.  Pretty cool stuff.  There are lots of Kyudo sites on the web with more info.