Birch bark backing

[Doug509]

I'm close to backing a sinew backed Yew bow with birch bark.  Should I use hide glue or some other adhesive?  I'm also curious what side of the bark looks better.  I'm leaning towards the lighter color.  Any suggestions?

[Pat B]

If you used hide glue for the sinew use it for the bark. I'd put the bark on as it came off the tree.

[Chumash]

I think, you should use the bark turned to 90 degrees, if you want to back the bow.
If you want to wrap the bow, you have the right direction.

[Burnsie]

Are there examples of bows that have had birch bark applied to the back of a bow.  I've thought about it often as a decorative look, similar to snake skins.
But I've always felt the birch bark would start cracking/splitting over time with the continual flexing of the bow?
I'll be watching this thread.

[willie]

looks like the bark is too thick in the photos for going over sinew
http://www.primitivearcher.com/smf/index.php/topic,68162.0.html
shows the use of the paperey outer bark

[Robert Pougnier]

I've used birch bark to waterproof a bow backing. It'll work fine with either hide glue or wood glue. If you use hide glue I would size the bark with very thin glue first.

I've applied it perpendicular to the direction you have it, with the side on the outside of the tree for the outside. I split mine less than paper thin using steam and it remained pliant enough to work dry after. I expect thick bark may crack once it's bent.

I've had good luck and plan on doing it again, I think it's a great look! There are some sweet turkish and egyptian bows that were covered with birch. Since paper birch grows in neither region I would assume it's benefit was well worth it.

[Doug509]

The bark I have is already cut vertically in 2" x 40" strips.  I cant flip it 90 degrees.  I pulled it apart into 1mm thick strips.  Its pretty flexible.  Will try to get it thinner if I can. I'll follow everyone's advice and mount it like it grew on the tree with hide glue.  If its a failure I can peel it off and sand it back to the sinew. Ill post my progress.

[Chumash]

You have to look at how the fibers run in the bark.
In this direction, bark is quite tensile strenght
In birch and cherry, the fibers run around the tree.
It is also important that the bark is very thin (< 1 mm) for backing. Birch bark can be easily divided into individual layers along the fibers.
Birch bark provides very good protection against moisture when used as backing over sinew. Composite bows were often wrapped entirely in  thin birch bark.
The best glue for the thin bark over sinew is hide glue.
First pic is for elm or hickory or cedar: the fibers in the bark run along the tree
Second pic: the fibers run around the tree ( birch, cherry).