04-28-2016, 12:50 PM
Salve Daniel,
The design I posted was based on the only period description of the onager. If you can get your hands on trees easy enough, it would stand to reason you select a curved trunk, hew it in half and the square it. This would give the humped shape and would lift the cordbundle and base of the arm well off the ground.
From your replies I gather you are not really all that concerned with authenticity, which is a bit of a shame, as why build the thing, then? Flax or hemp rope will give you good torque, as you pre-tension your bundle using the rachet. As the onager uses a sling, this greatly increases the range. Note also the downward bend in the end of the arm. This is based on the description as well. Pre-tensioning your rope will also Ensure you will break the arm if you allow it to crash into the ground unchecked. Also, it will put great strain on your construction. The ancient source clearly describes an arresting mattress. The rock, by the way, is long gone before the arm is arrested by the padded mound.
Presently, I am engaged in researching and building a traction catapult. I hope to publish the results in Medival Warefare Magazine later this year. Less Romans these days, more Franks!
The design I posted was based on the only period description of the onager. If you can get your hands on trees easy enough, it would stand to reason you select a curved trunk, hew it in half and the square it. This would give the humped shape and would lift the cordbundle and base of the arm well off the ground.
From your replies I gather you are not really all that concerned with authenticity, which is a bit of a shame, as why build the thing, then? Flax or hemp rope will give you good torque, as you pre-tension your bundle using the rachet. As the onager uses a sling, this greatly increases the range. Note also the downward bend in the end of the arm. This is based on the description as well. Pre-tensioning your rope will also Ensure you will break the arm if you allow it to crash into the ground unchecked. Also, it will put great strain on your construction. The ancient source clearly describes an arresting mattress. The rock, by the way, is long gone before the arm is arrested by the padded mound.
Presently, I am engaged in researching and building a traction catapult. I hope to publish the results in Medival Warefare Magazine later this year. Less Romans these days, more Franks!
