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Korean Traditional Archery → Bows → Applying Birch Bark Backing
I was wondering if anyone has experience applying birch bark to their bow? I have a SMG with artificial bark that I'd like to replace with real bark but would like more information about how to do it properly before attempting the job myself. Anyone know what kind of glue is used, what kind of varnish (if any)? A step-by-step guide would be hugely helpful.
I've been thinking about and researching it because I want to overhaul my bow too. Replace the old cracked birch, redo the bindings (from monofilament to something more natural), grip and the leather wraps on the nocks etc
The traditional method is to store the bark in seawater for a year and boil it just before you stick it on with fish bladder glue. Nowadays they use rubber cement. Karpowicz has the following to say in his book:
There were reports from Korea about soaking the bark in sea water for a year to achieve greater flexibility and about boiling prior to use. I believe the soaking does not allow the bark to become dry, while salty water prevents spoilage. I have not found such bark to be any more flexible, however. The bark when boiled in water becomes very soft and rubbery and swells to form wrinkles at the lenticells.
Unfortunately, when taken out of hot water it immediately hardens again. I found alcohols, isopropyl (so called “rubbing alcohol”) or ethyl alcohol, much more effective in softening bark, since the bark stays softer for a longer time until the alcohol evaporates. One can, of course, experiment with other solvents to take advantage of this property. Instead of soaking, the bark can be exposed to vapors of alcohols, mixed half-half with water in a stack of wetted tissue.
In my experience rubbing alcohol evaporates quicker than water... I don't know, will have to experiment
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very interested in this thread
Red plant fiber (linen? hemp?) braided thread for wrapping, or silk is what I'd try if trying to be authentic. what was used? But I'll probably just end up using red polyester thread...
How do they make it smooth and not pale white? maybe the paleness depends on the species..
Komárcsevics Sándor makes some awesome birch backing in his bows...
Thanks for the replies, very interesting. Someone forwarded me this link:
https://www.youtube.com/watch?v=o6qRnTVM2KU
The bowyer applies the bark at around 2:00. Seems he boils it and applies it in strips using (fish?) glue. I wonder if the best method would be applying it with fish glue, which is water soluble, after the bark is softened, and then spraying the bark with some kind of water-proof sealant, like the stuff used by art students to seal a charcoal or pencil sketch?
Someone also suggested applying the birch bark in a very thin single layer, and then adding one more thin layer on top.
"I've been thinking about and researching it because I want to overhaul my bow too. Replace the old cracked birch, redo the bindings (from monofilament to something more natural), grip and the leather wraps on the nocks etc"
I was thinking of doing the same thing, replacing the bindings with some strong nylon thread. Any good tutorials for this? Will it be strong enough (as strong as the monofilament used on the SMG)? I've seen some bows with much longer bindings (sometimes it seems like they've wrapped thread over half of the bow), wouldn't this have an impact on the flexibility of the bow?
+1
Impact on flexibility?? It'd just add a little extra weight I guess. Those just seem to be done on the horn/sinew bows to keep them from delaminating/cover up repairs, or for aesthetic reasons, I think. though it could also help the synthetic bows from delaminating.. maybe...
Maru wraps hemp until mid-limb, then varnishes it?? also puts ray skin next to the grip. https://www.facebook.com/taesik.seo.5/p … 3913620888
You would use a serving wrap or a whip finish for thread.
I wouldn't spray the bark, just maybe rub it with shellac. I wonder what to add to the shellac to make it more flexible.. maybe the button lac is flexible enough already. but it probably wouldn't look like those Korean bows. They seem to use oil and/or wax, maybe tung oil would work nicely. Or tea seed oil. Or.. sunflower oil?!? Some oil that doesn't go rancid.
Thanks for the replies, very interesting. Someone forwarded me this link:
I have a subtitled version here: https://www.youtube.com/watch?v=cicYRzWss74
+1
Nice! Thanks!
https://www.youtube.com/watch?v=cicYRzWss74#t=19m45s - sinew? Not silk? Both? So now they use synthetic fiber even for the hornbow strings.. interesting
Maru wraps hemp until mid-limb, then varnishes it?? also puts ray skin next to the grip. https://www.facebook.com/taesik.seo.5/p … 3913620888
You would use a serving wrap or a whip finish for thread.
I wouldn't spray the bark, just maybe rub it with shellac. I wonder what to add to the shellac to make it more flexible.. maybe the button lac is flexible enough already. but it probably wouldn't look like those Korean bows. They seem to use oil and/or wax, maybe tung oil would work nicely. Or tea seed oil. Or.. sunflower oil?!? Some oil that doesn't go rancid.
Hmm, I like the idea of using tung oil for the varnish. Might try that.
pclgorman wrote:Thanks for the replies, very interesting. Someone forwarded me this link:
I have a subtitled version here: https://www.youtube.com/watch?v=cicYRzWss74
Thanks! Ah, so he is applying the bark when it's still damp.
권무석's bows seem to have longer, more reflexed tips than others (like the older style?). Sounds like less stack and better shooting, and I think it looks better. I think I'd really like a horn bow from him in the future, if I could get one..
I just heard back from someone who works with Korean bowyers. He asked them how they attach birch bark and was told they use synthetic glue (like that used for wood or plastic), diluted with paint thinner and applied several times (2-3) over both the bow and the strips of bark before attaching them. He also said they normally insert a sponge-like material between the bark and bow.
Korean Traditional Archery → Bows → Applying Birch Bark Backing
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