stoneagebowyer wrote: Can you give us some rough dimensions?
Limbs 25x18mm mid limb.
Prod length 52 cm front
47 cm rear
Arms 10cm long 8x22 mm middle, 5x20mm tips - tapering edges.
String length can be varied , but 42 cm for 105#.
A bit longer 45 cm string 80# weight seems to be more efficient with ultra-light bolts.
How hard or easy is it to span?
Just step on the rear bow and pull off the front bow.
Assembly and dissassembly goes in couple seconds.
It looks like it would be an ideal survival weapon, far easier to make
String tied to simple knotted cables allows measurable power stroke with practically zero limb movement. Meaning prod can be made of very low quality material as they don't need to bent much. As a bonus comes good mass efficiency and high bolt velocity.
Ever think of making one with more refined components?
Sure. This is not the first one.
Just the first with nothing new. And with decent ergonomics.
was published January 2004 in Paleoplanet or Primitive Archer forum. That one and all other previous ones had some untrained features wich did not work as well as they could.
The next one will have something new .
A separate modular prod unit. Just plain block of wood between the bows. This should allow more freedom designin the "user interface".
Limbs could be made faster with longer power stroke. This would put less strain on the cables and throwing arms allowing them to be lighter.
This latest unit here has calculated dry-fire speed ca. 250/ms or bit less. And this design is intended for sport shooting in camping environment. It is optimized for durability,ease of use and transport - not speed or power.
If the effective inertia per stored energy can be sqeezed to quarter of what this has( technically feasible), the dry-fire speed can go up to 450-500m/s. Allowing practical projectile speed of mach 1.1 or so. -We don't need a chrono to hear that.
And one nice feature about this arm-cable system: This can be safely dry fired. The throwing arms have enough mass to absorb practically all energy from limbs and cable. They are not fixed to the cables, only hooked there. So if there is too much energy left after bolt the arms and string simply fall off.
Last edited by hullutiedemies on Mon Mar 09, 2015 6:13 am; edited 1 time in total (Reason for editing : fixed imagelink)