does it make a difference....core wood

[RT]

Hi all,

I am looking to make my next boo back n belly bow.

does it make a dufference in terms of performance if I used 1 soft wood or 2. Hard wood for the cire?

Please feel free to share? 

[mikekeswick]

A core needs to be resistant to shear so a diffuse porous wood is best no weak earlywood.
It would also be a bonus if it glues well and isn't overly dense.
These things point to maple. Acer saccharum is the best core wood. Sycamore also works for the same reasons - acer pseudoplatanus.
Forget softwoods - no shear strength along the earlywood.

[RT]

Thanks mike

[PatM]

Mike, you are confusing true Sycamore with" Sycamore Maple". Two different trees. I wouldn't be surprised if the wood of either is rather similar though.

[streamflyer]

If acer sacharum is a great core wood how does acer rubrum and sacharinum compare. are any better in tension as well?

[DarkSoul]

PatM, Mike is not confusing anything. What someone from the United Kingdom calls 'sycamore', is indeed a maple. While a person living in North America refers to a planetree species when they talk about sycamore. Mike is just illustrating the confusion that exists with vernacular names. Luckily he also included the scientific name of the species, so it becomes perfectly clear which species he means.

Streamflyer, in principle all maples share more or less the same mechanical properties of the wood that Mike lists. One species may be denser than the other, but they're all diffuse porous and easy to glue. Acer rubrum can probably be used for cores as well. It is just not as dense as A. saccharum or hard maple. It may therefore be not as resistant to shear. A. saccharum is definitely better in tension, but that characteristic is not needed for core woods.