magnolia

[bowralph]

Hi all, is there anyone among you who build a bow from Magnolia ,i got a nice piece and wonder if its worth the work ??
ralph

[zenmonkeyman]

About all you can do is build one and see if it works!  Look up the specific gravity at the USDA tree site or elsewhere (maybe it's listed in TBB4?) and start with Tim Baker's rule of thumb about safe final bow weight:  For a 65" bow 1.5" wide at the fades, the safe draw weight equals the specific gravity of the wood used.  Or something to that effect.  Then, when you're done, post a full draw photo, and win BOM!

[beetlebailey1977]

Has a .5 gravity and is listed as a border line bow wood.  I say go for it and make a bow.

[johnston]

Beetle, zen, please tell me more on this specific gravity stuff.

bowralph let us know how it works. Got me a magnolia to cut down and would hate to waste bow wood.

Lane

[zenmonkeyman]

Firstly, I must correct myself.   It's 2" at the fades not 1.5".
Specific gravity is a measure of density.  It is calculated most easily in the metric system, where 1 litre of water weighs 1 kilogram.  Water has a specific gravity of 1.  Which is very handy, because we can now discover the SG of any substance whose SG is less than 1 by simply dunking it and measuring what percentage of it is below water level.  With wood, carve a "cylinder" (which doesn't have to be round), and dunk it in a tall narrow container of water, like a test tube for instance.  As long as the wood is dry, you can simply calculate the SG:  Inches of wood below water divided by length of cylinder equals SG.  If the SG is higher than 1, you have to calculate the hard way, because anything between 1 and infinity SG will sink to the same bottom.  Basically, if the SG is .5 as BB77 says, you should be able to make a 50lb bow out of it.  If it's a borderline bow wood, make it longer than 65" though.  Start at 72" maybe.