Hi,
I am starting the horn bow project too...
For the cores I have
-vertical grain bamboo flooring boards cut into the 5mm thick and 30mm wide strips
- and for Second bow is the acacia wood cut into 5mm plates too (exact vertical grain), strips are 30mm wide
-handle is acacia wood 25mmx 25 mm crosscut strip
Siyahs:
I wont bother with steam bending thick hard wood....
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I decided to make glued plywood siyahs
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- from 5mm accacia or bamboo plates glued in the form. I will bend 3 strips together to get the exact thickness.
I already made a wooden form - exact copy from pictures of the turkish bows in museum