how many pieces of sinew?
I am planning on ordering deer sinew to back a bow I am going to make based on the MB bow, so there will be about 40 inches of the bow that needs backing.
How many pieces of leg sinew would I need? How many pieces of backstrap sinew?
Thanks,
Evan
How many pieces of leg sinew would I need? How many pieces of backstrap sinew?
Thanks,
Evan
Evan Painter
It depends on how many layers you need as well as the length of sinew.If the bow is not very heavy,say 40kg ,5 pieces of backsinew will be enough.You need another 3--4 pieces to wrape the joints and the handle. If leg sinew ,4--5 are ok.
I was once told by a traditional bowyer :1mm of sinew will increase about 5kg's draw weight. Reduce the thickness of sinew if your horn strips are really thick.
I wish it can help you.
It depends on how many layers you need as well as the length of sinew.If the bow is not very heavy,say 40kg ,5 pieces of backsinew will be enough.You need another 3--4 pieces to wrape the joints and the handle. If leg sinew ,4--5 are ok.
I was once told by a traditional bowyer :1mm of sinew will increase about 5kg's draw weight. Reduce the thickness of sinew if your horn strips are really thick.
I wish it can help you.
Thanks
Those numbers are similar to what I had heard before, but that was from someone that didn't have experience with hornbows, so I wanted to make sure, thanks. The leg sinew says 6 to 10 inches, the backstrap doesn't give a length, but appears to be at least 14 to 15 inches. Would the backstrap be better because of the length?
Evan
Those numbers are similar to what I had heard before, but that was from someone that didn't have experience with hornbows, so I wanted to make sure, thanks. The leg sinew says 6 to 10 inches, the backstrap doesn't give a length, but appears to be at least 14 to 15 inches. Would the backstrap be better because of the length?
Evan
It's not how many of them but how much. Put them on a scale. And how much is depending on the limbs area and bow weight.
It depends how thick is your sinew layer. Usually a safe thickness is 3mm for a mid weight bow, so for a 100cm total length x 0.3cm thickness and 4cm width the volume of layer will be about 120 cm^3. The spec. gravity of dry sinew and glue is 1.2g/cm^3, whch gives you 120 x 1.2 = 144 grams for the layer. About 40% of that is glue, so you need about 90 grams of sinew. Add 20% for waste and the mass of tendons you start with to shred is 110g.
It is best to have the entire length of the bending section covered with one length of sinew bundle for the last layer. The bundles must overlap by about 4cm or so.
Adam
It is best to have the entire length of the bending section covered with one length of sinew bundle for the last layer. The bundles must overlap by about 4cm or so.
Adam