11-19-2012, 04:34 AM
Right! Now, as to the boom or pole. If you say the rope bundle was not pre-tensioned, that makes sense as in doing so the boom would not remain upright in the weapon. Any tightening rotation of the bundle would tilt the boom front. This would also imply the boom would have to have had a larger contact area to the rope to prevent lateral movement (falling to one side). The boom would need to be wedged between the ropes tightly. This action may have the effect of tightening the ropes enough to be able to hold it in an upright position. This would also imply the boom having a larger/wider base and tapering quickly to a more uniform diameter. The more weight in the upper stretch of the boom, the slower it would fire due to the inertia of the boom itself. Has anyone made a working model of this design, I am wondering ??
The above would rule out having to use a washer, in my mind. To fix the rope bundle to the frame on assembly, pieces of wood or iron would need to be inserted through the eyes of the bundle after passing them through the frame. These could be wedge shaped to allow them to pass through and then tighten the rope bundle. Two pins would be enough to stop the wedges rotating, although even friction could be enough. In my evolving theory, the bundle of rope would have been pre-wound and lashed to hold its shape. It would be a proper pain to have to thread the rope- bundle through the holes in the frame each time the piece was set up for action. Now, I am working on the assumption the onagers were carried in parts on a cart, and when the need arose, quickly assembled to be able to fire as soon as possible. One cart could hold one or two onagers and ammo, depending on the size. I wonder how big or small one of these had to have been to be both practical and effective? Is there any data on the weight of rock/missile these would throw?
Rock like granite or hard/dense limestone has a specific weight of about 2.5 kg (five pounds) for a cubic decimeter (10 cm or about 4 # squared). A ball of 15 cm diameter would weigh about 3 kg or 6 pounds. With some speed behind it, that would have quit an impact on the receiving end.
I hope this thread inspires a lot of onagers being build, as they would seem really handy weapons and relatively simple to both make and transport. With the design that is beginning to emerge, one of these could be assembled in less then half an hour by four men. Any group could have their own artillary cart :woot:
Ahhh, and I have just found a 2 meter long ash 1/4 section of a log waiting to become a bow. Just the bark removed. I just hope 2 meters will be enough for the boom. That ash could work like a charm for this, as it is straight grained and has been drying for a few years now. Would that be suitable?
The above would rule out having to use a washer, in my mind. To fix the rope bundle to the frame on assembly, pieces of wood or iron would need to be inserted through the eyes of the bundle after passing them through the frame. These could be wedge shaped to allow them to pass through and then tighten the rope bundle. Two pins would be enough to stop the wedges rotating, although even friction could be enough. In my evolving theory, the bundle of rope would have been pre-wound and lashed to hold its shape. It would be a proper pain to have to thread the rope- bundle through the holes in the frame each time the piece was set up for action. Now, I am working on the assumption the onagers were carried in parts on a cart, and when the need arose, quickly assembled to be able to fire as soon as possible. One cart could hold one or two onagers and ammo, depending on the size. I wonder how big or small one of these had to have been to be both practical and effective? Is there any data on the weight of rock/missile these would throw?
Rock like granite or hard/dense limestone has a specific weight of about 2.5 kg (five pounds) for a cubic decimeter (10 cm or about 4 # squared). A ball of 15 cm diameter would weigh about 3 kg or 6 pounds. With some speed behind it, that would have quit an impact on the receiving end.
I hope this thread inspires a lot of onagers being build, as they would seem really handy weapons and relatively simple to both make and transport. With the design that is beginning to emerge, one of these could be assembled in less then half an hour by four men. Any group could have their own artillary cart :woot:
Ahhh, and I have just found a 2 meter long ash 1/4 section of a log waiting to become a bow. Just the bark removed. I just hope 2 meters will be enough for the boom. That ash could work like a charm for this, as it is straight grained and has been drying for a few years now. Would that be suitable?
