Ever use dental floss as substitute for sinew?

[Gimlis Ghost]

Probably not a good thing to ask of purists but its more an academic question than anything else.

Many years ago I used dental floss to make a couple of bow strings. They worked out surprisingly well. I'd run across the idea in a book on building cross bows. I also used the DF to bind fletchings and arrow heads.
The same book told of using dental floss as a substitute for sinew in backing a bow or rather a prod of a crossbow.
I'm assuming this would be considered non kosher for a true replica primitive bow.
I'll be doing a bit of experimenting using some wood harvested from trees I'm clearing, unlikely to be the best wood anyway.

Ran across a very tall and very straight sapling yesterday that grew to block opening one side of a gate. Its got to go anyway so I might as well put it to use. Don't know the species yet because its surrounded by much taller trees and none of its own leaves are visible from the ground. Should be enough straight un knotted wood there for a light Indian bow at least.

I figure to make it and test it without backing then try the DF as backing to see how much difference it makes.

[Pat B]

Dental floss is basically like artificial sinew, nylon or dacron. It would be good for binding fletching but not as a substitute for sinew backing of a bow. Brown grocery bag paper and TBIII would make a better backing if any backing is needed. If the small tree is a good bow wood and long enough you may not need a backing. First find out what the wood is and how long it is then you can decide where to go from there.

[Gimlis Ghost]

Thank you for your input.

I'm fairly sure there's at least enough straight wood in this sapling, more like a young undernourished tree, to make a bow six feet long, though I'll probably make it four and a half ft.
The bark has an unhealthy look but that's mainly due to too much shade. There are no lower limbs, all its growth seems to have been directed to growing tall enough for the upper limbs to reach sunlight.
Its about three and a half to four inches thick and very straight.
I figure it would have to be good wood to maintain such straight growth in such inhospitable conditions.

If unsuited for a bow I can make a stout walking staff.

PS Nylon can stretch but Dacron won't stretch. Far as I know only dacron is used for dental floss. I do know it makes a good bow string. I used a DF string much smaller in diameter than standard for many years on a 45 lb fiberglass bow. I replaced the string with a proper commercial product years ago but not because it wasn't still serviceable.

[Digital Caveman]

anything will stretch at least a little if you pull it hard enough (except maybe for bottle glass ) but I know what you mean.  I have used floss for wrapping feathers in the past.

[Pat B]

I keep floss in my bow tool box for quick repair when needed. And, Dacron will stretch.
 Can you post pics of the sapling? If you are not sure of the wood for bows a longer bow(6') would be better than a short(4.5') bow.

[Gimlis Ghost]

I keep floss in my bow tool box for quick repair when needed. And, Dacron will stretch.
 Can you post pics of the sapling? If you are not sure of the wood for bows a longer bow(6') would be better than a short(4.5') bow.

I'll lay a spread of leaves on the scanner later. Don't have the software to load images from my camera.
I just now finished cutting down the sapling and cutting all the limbs off the upper half.
The lower half had no limbs but turned out not to be as straight as it looked at first, the first two feet had a curve from growing away from the gate then it curved back further up. The shape of its curves might even be of some advantage .
Unfortunately there little or nothing of heart wood only a pencil diameter bit.
The wood is white and tough.

The upper half turned out to be much straighter but had a few limbs which were large enough in diameter that I'm sure it has large knots.

Funny thing but the entire appearance of the bark changed radically below the first limb with a clear line of demarcation . It was as if it was two different species. The lower bark is very rough while the upper is a smooth skin.

Theres enough straight wood on the upper limb wto make a good stout walking staff or even a quater staff, around seven feet.

[willie]

polyester will stretch a whole lot less than nylon   3% vs 30%

are you thinking of adding a thin layer to protect the back or a substantial layer as with composite construction?

[Gimlis Ghost]

At this point I don't think this wood will be suitable. I'm pretty sure its Black Walnut.
I have a couple of very old Black walnut trees nearby. The leaves look much the same though there's a variation in the size and sharp angle of the saw toothed edges.
Looking up BW saplings I found this is probably it. The sapling looks a lot different than the mature trees would.

I'd been considering a thin layer anchored at each nock point. If I decided on a thicker layer I have a couple of old Kevlar panels a friend gave me after testing a flack jacket to destruction. Un weaving these would supply some long fibers that could be built up into a substantial layer.

[willie]

Kevlar is very stiff, much stiffer than either polyester or nylon. 

sinew is added to bows in various amounts for different purposes. a thinner layer to protect a wood bows back, and add a little performance gain, and quite thick layers, such as seen in a hornbow where it is essentially the whole back of the working limb by design, ie a composite, a design quite different from a wood bow.

a thicker layer of kevlar on a wood bow design would redistribute an excessive amount of stress to the belly. It would not take very much at all to protect an iffy back material though.

[Stickhead]

No advice here, but it does make a great string nock.  Your post got me wondering (now that my gums are receding as fast as my hair), I wonder if the natives used sinew for dental floss?

[PatM]

I just want to say that the bark sounds pretty normal for many trees.