Backing a self bow

[ccase39]

I have a couple of staves of Osage that may be salvageable. They have a good bit of twist and stuff but they were good for practice. I took them down maybe a little to far
And may have violating a ring or two. I was thinking of backing with boo. Do I have to bet the entire back flat like a board bow?

[Eric Krewson]

Before the naysayers chime in and tell you twisty stave cut through the grain will fail with a bamboo backing I can assure you it won't and is a good way to save a marginal stave.

I have backed around 30 such staves with no failures and suggest you completely flatten the back of your osage and glue the bamboo from tip to tip. Make your bamboo edges about 1/16" for the entire length of the backing, this will naturally taper the bamboo from handle to tip on both limbs.

Here is a similar stave I backed that is still shooting after a bunch of years, lots of runout but it doesn't matter with a bamboo backing.



 

[Del the cat]

Yup, you have to get it dead flat to ensure a good glue line. It can undulate along the length, but you want dead flay across the back and no (or very little) twist.
Time spent in preparation is the key to a good glue line
Del

[ccase39]

Do you have to do the belly relatively flat too .

[snedeker]

the belly can be somewhat rounded.  Also, one other option would be to back with silk or linen fabric

[Del the cat]

Do you have to do the belly relatively flat too .

Belly would just be shaped normally to suit the style of bow and the tiller. You only need a flat face for the glue line.
Del