The following are available for blade core layers. The photos are taken from my own inventory and provide a representative example of the character of the wood species. My goal is to find core woods that are lightweight in order to balance against the heavier/harder outer plies.

The core woods are listed in order from lightest to heaviest.


Ochroma pyramidale
Janka: 100
Specific Gravity: 0.17

1.5mm, 2.4mm, 3.0mm, 4.8mm, 6.4mm

Basswood / Lime

Tilia americana
Janka: 410
Specific Gravity: 0.32

1.5mm, 2.4mm, 3.0mm, 4.8mm, 6.4mm

Ayous / Obeche

Triplochiton scleroxylon
Janka: 490
Specific Gravity: 0.36

1.5mm, 2.4mm, 3.0mm


Aningeria altissima
Janka: 930
Specific Gravity: 0.40


Douglas Fir

Pseudotsuga menziesii
Janka: 700
Specific Gravity: 0.53