Plant Fiber Backing Info Needed.

[Prarie Bowyer]

I saw on another tread that "flax" could be used in lieu of sinew  .  That got me thinking nad as i'm looking around for a souce I discovered that there is also a spinable weavable bamboo product and something called "Ramie"

"Ramie fibre is white with a silky lustre, similar to flax in absorbency and density but coarser (25-30 microns). One of the strongest natural fibres, it has low elasticity and dyes easily".

Can anyone enlighten me on the process of backing with these plant fibers?  What types are best, and how to get them? I'm guessing prespun raw unbleached fibers.  What about the gluing process and how much to use?
 


thoughts?

[Prarie Bowyer]

Well??/  anybody?

[Peacebow_Coos]

You might be able to find something on a google search for this I seem to remember a flax backed bow a while back.  I've never used fibers but from what I've gleaned off here and paleoplanet you can use just about any fiber (the tougher the better depending on the wood)  and lay a layer of glue down to size the back.  Then apply like sinew, dip bundles in glue and brickwork it on there.  I don't think any fiber could be used as sinew is for extra draw length and weight/performance but for an added layer of protection and some moderate weight gain.  Sinew is king   If you're gonna use fibers get them as raw as possible and try it out I'd like to see what this ramie fibre is all about, I just sanded a bamboo backing strip down today and was amazed by the dust/fibrous mass that was produced.  Bamboo is tough, I don't see why it wouldn't work.  Try Titebond 2 or 3.

[TimBo]

If you have The Bowyer's Bible, Vol. 4, there is a good section on flax (and lots of other backings) in the Design and Performance Revisited chapter (pg. 134-135).  "Flax, hemp, dogbane, nettle, ramie, milkweed, and other similarly strong vegetable fibers all behave much the same", it says.  A flax and/or linen canvas backing is on my list of things to try, along with making flax or milkweed strings.  Hopefully someone with more flax experience will come along and jump in.

[steve b.]

What TimBo said. 

My opinion based on what I've read and seen it that the plant fibers, overall, are best, as they are much lighter than sinew and very strong.  Again, based on my experience, sinew is really good for only one thing from an efficiency standpoint--keeping short bows alive.

I have a few miles of Jute that I am going to try as backing asap.

[PatM]

Rather than laying these fibers down in the typical fairly haphazard manner I would attempt to make a reconstituted unidirectional fiber backing with any of the  fibers listed and set them in Epoxy.
 I would make some sort of shallow channel with a non-stick surface and fill it carefully with fiber and glue laid in place and tensioned and then place a compression strip on top of the channel and compress it.
 After it cures it could be popped out and applied to a flat stave with some reflex.

[campx]

Not to toot my own horn, but last week I finished a bow for my daughter, and I used milkweed fibre in a strip down the back, glued on with TB2.  I don't have a scientific formula, but it is strong stuff.  Real strong.

[Prarie Bowyer]

I found two sections on plant fibers in the TBB.  There is a concern that Flax while strong as nails could possibly overpower a bow?  (see volume one) so it must be used sparingly.

It looks like on the test pine bow it was spun into bow length treads?  I'm thinking of spinning it, or bamboo (which is not as strong apparently) into the same then cutting it in sinew lengths and putting it down like sinew.

Also a verry elusive reference to Nylon backing that performes in streatch similar to Sinew.  Nylon is also available in roving that can be spun into thread.

Additionaly the "China Grass" from volume 2 is actually Raimie.  Rated the strongest.  FWIW. 

Some of these can be spun into strings.

I'm going to try the nylon and flax.


Where did you get the milk weed?

[campx]

Milkweed grows in abundance around here.  Gonna go cut a bunch of it soon.  The last stuff I tried stripping out was from dried out stems, kind of tough going.  We'll see how it goes, in green form......

[Prarie Bowyer]

kinda how flax is gotten.  rot the weed and pull the fibers out.

[JackCrafty]

 
Good thread.  I've spend many hours wrestling with plant fibers instead of sinew and here are my observations so far:

ALL the plant fibers I've tried will stack sooner than sinew and will not allow draw long lengths without damaging the back or the belly.

The flax I tried was quite weak and I think it was due to the fact that it was retted too long. The other fibers were obtained from commercial twine or cord: jute, sisal (which is actually the same as agave), cotton, hemp, and manila fiber.

Nylon may be the answer but I still haven't found a good way to glue down individual strands as opposed to nylon fabric.  Some say hot melt glue will work well with nylon but I haven't tried that yet.  Seems like it would be very difficult over a large area, so I put the idea on the back burner.

Hide glue seems to work best.  Knox glue also works.   Fish glue is too brittle unless you make your own from fish bladders.  Titebond also works well but it does not spring back as fast as hide glue.  It will eventually pull itself back into shape, though.

Seasoning and processing my own fibers has always worked best for me and anything that can be used for a bowstring can be used for backing.  And I never cut down long fibers before I put them on a bow.  I put them down in the longest strands I can get and I toss out the short fibers.  I also found that combing the fibers throughout the process makes a BIG difference in how they lay down.

As a final note, all fibers dry in different ways and some will not lie flat when drying unless you wrap them down.  So, as a default procedure, I wrap everything.

[Carson (CMB)]

Interesting observation on the stacking of plant fiber vs sinew, Jackcrafty.  The bow I glued silk fibers on is long overbuilt American flatbow of yew.  I am wondering if plant or silk fiber/hideglue works best in long-limb designs.    I guess i need to get that bow bending and find out

[JackCrafty]

Silk is a protein so I don't think it stacks like plant fiber.  I don't have any experience with silk so I don't know for sure.   
The fact that sinew was used in the orient as opposed to silk (where it is plentiful) makes me think that even silk is not as good as sinew.

[Prarie Bowyer]

I'm looking heavily at ramie - china grass, flax or nylon roving material. 

[JackCrafty]

Ramie doesn't sound like a good material for backing bows.  I wouldn't use it personally because of its low elasticity.
From Wikipedia: 
Because of its high molecular crystallinity, ramie is stiff and brittle and will break if folded repeatedly in the same place; it lacks resiliency and is low in elasticity and elongation potential.[5]

[5] Kadolph SJ, Langford AL. Textiles (9th ed.). Upper Saddle River, NJ: Prentice Hall; 2001.