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Main Boards => The Bowyer's Bench => Topic started by: McK on June 26, 2009, 05:01:00 PM

Title: Osage question
Post by: McK on June 26, 2009, 05:01:00 PM
I understand the sg of Osage is around .82.  I tested a couple sample pieces off a stave I am working on. A thumb sized piece when gently placed in a glass of water sunk directly to the bottom.  This is a dry piece of wood tested at 7% with a meter.  A same sized piece from a previous stave floats with about 85% submerged. My question is is this unusual and should the design of the bow differ from a typical osage design?
McK
Title: Re: Osage question
Post by: Pat B on June 26, 2009, 05:13:00 PM
I've never done a s g test on any wood. I just build bows out of them and so far I've been quite successful.
Title: Re: Osage question
Post by: bigcountry on June 26, 2009, 06:29:00 PM
For it to sink to the bottom means it has over a SG of 1.0.  Sounds strange to me.

I like just whittlin on wood myself.  But sounds like interesting experients.
Title: Re: Osage question
Post by: shamus on June 27, 2009, 09:51:00 AM
I don't test SG. I just make the bow.
Title: Re: Osage question
Post by: DCM on June 29, 2009, 09:01:00 AM
Wood varies a great deal from one specimen to the next.  The published numbers are averages.  Sounds like yours are both a little on the dense side, but yes that's normal.  The more dense the wood, generally the less volumn you need.  Most folks make 'em more narrow, but shorter is an options too, particularly if you are at or under 1" at the widest point.  Width provides for a little more lateral stability.
Title: Re: Osage question
Post by: Don Stokes on June 29, 2009, 10:22:00 AM
The specific gravity of pure wood substance is about 1.43. Osage heartwood tends to have the cells clogged up with "extractive" chemicals, which bulk it up and increases the density. A good dense piece can easily exceed 1.0 with just a little water in it.

Makes lousy rafts.
Title: Re: Osage question
Post by: McK on June 29, 2009, 02:12:00 PM
Thanks, was just curious, am aiming for a 68" flatbow and was wondering just how narrow I needed to make the limbs toward the tips.  Might be better off making it a little shorter.
McK
Title: Re: Osage question
Post by: George Tsoukalas on June 30, 2009, 08:47:00 AM
If I find a limb not responding to thickness removal I begin to narrow the width little by little. Took me quite awhile to g=figure that out years ago. That kind of accounts for the differences in density.  :)  Jawge
Title: Re: Osage question
Post by: Springbuck on July 09, 2009, 09:01:00 PM
Not an osage expert, but wood does all kinds of stuff.  I have cut black locust grown in Utah that was .84 or so.  BL is supposed to be like .75 or less.  I attribute that to most of our water coming in winter, not spring, short springs and then the tree growing in a watered yard through many hot summers...
Title: Re: Osage question
Post by: Roy Steele on July 18, 2009, 05:36:00 PM
I'm with PAT I just build bows.Ofcourse all of my staves are at least 5 or more years old.I  never test and for quite a few years now I only build Osage mainly.No heat,no backing fairly straight staved bows.
   These make the most durable bows that last forever.Over the years these are what I've grown to love..