Core
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.
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Balsa
Ochroma pyramidaleJanka: 100
Specific Gravity: 0.17
1.5mm, 2.4mm, 3.0mm, 4.8mm, 6.4mm
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Basswood / Lime
Tilia americanaJanka: 410
Specific Gravity: 0.32
1.5mm, 2.4mm, 3.0mm, 4.8mm, 6.4mm
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Ayous / Obeche
Triplochiton scleroxylonJanka: 490
Specific Gravity: 0.36
1.5mm, 2.4mm, 3.0mm
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Anigre
Aningeria altissimaJanka: 930
Specific Gravity: 0.40
1.5mm
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Douglas Fir
Pseudotsuga menziesiiJanka: 700
Specific Gravity: 0.53
1.5mm