Author Topic: Minimal moisture level for bamboo backing  (Read 2008 times)

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Offline Matthias Wiltschko

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Minimal moisture level for bamboo backing
« on: February 11, 2014, 02:42:47 pm »
Hi guys!

I am planning on making a bamboo backed bow.

Question is, does bamboo like very low moisture levels around 5%?
The lower the moisture level the harder the belly.

Hickory works best at about 7% moisture.
Sinew and rawhide get critical under 3% as far as I can tell.

All the best
Matthias
Bowyers are not flexible, they are elastic!

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Offline 4dog

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Re: Minimal moisture level for bamboo backing
« Reply #1 on: February 11, 2014, 03:20:52 pm »
gonna watch this...i got a nice piece of bamboo...dry dry dry...been wondering when and if bamboo is "too dry to use" .
"SET" is always there !!!

Offline PatM

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Re: Minimal moisture level for bamboo backing
« Reply #2 on: February 11, 2014, 03:38:12 pm »
It will definitely be less prone to popping slivers if it is not as dry. Bamboo is very hygroscopic but that doesn't mean it can't get too dry if the RH is low.
 Much safer to have it at a higher moisture content.

Offline RBLusthaus

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Re: Minimal moisture level for bamboo backing
« Reply #3 on: February 11, 2014, 06:38:38 pm »
Can't remember what he said, but I think Torges discussed  this in his bamboo backed video.   He keeps his boo in s hot box prior to use.  I do the same, and the room had a dehumidifier running, but I never check moisture content of my boo.  Russ

Offline WhitefeatherFout

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Re: Minimal moisture level for bamboo backing
« Reply #4 on: February 14, 2014, 02:16:06 am »
I like to run around 6% on boo before backing.  I'm fairly certain it will gain some moisture from the wood if the wood is above that but I'm not sure and it may be a negligible amount and it would also depend on how well your specific glue transfers or inhibits moisture.   On hickory, I like to match the mc at around 6% to the boo. 

Offline Eric Krewson

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Re: Minimal moisture level for bamboo backing
« Reply #5 on: February 14, 2014, 10:06:20 am »
I like mine dry, dry to start with but like the wood you use for a core it will stabilize at what ever the M/C is in your area, here in Bama that is 12%. I keep my bows in the house so the M/C probably averages a little less than outside.

Offline Badger

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Re: Minimal moisture level for bamboo backing
« Reply #6 on: February 14, 2014, 11:43:46 am »
  For a thin piece of bamboo backing the moisture level is not critical. Too dry could be a problem but anywhere in normal ranges should be fine. Cellulose fibers get stronger in tension when wet, once they go below about 6% they start weakening. I would say anywere between 6 and 12% would be fine. Where I live they seem to settle in about 8% which is fine.

Offline Traxx

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Re: Minimal moisture level for bamboo backing
« Reply #7 on: February 18, 2014, 01:28:09 am »
Funny you should mention this....
I was just talking with someone about this very thing tonight.We have noticed,that Bamboo backings and cane shafts have a serious tendency,to split and check in our very arid conditions in the Great basin.