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    Huge steel prod for a catapult

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    HeroSK
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    Huge steel prod for a catapult

    Post by HeroSK on Mon Oct 20, 2014 2:18 am

    Hey all,

    I just found images of an interesting catapult powered by huge steel prod that apparently built in similar manner with ordinary steel prods for crossbows but in much larger scale. This catapult located in Grandson Castle in Switzerland. I would like to hear your opinions and it would be great if someone could supply more information such as time period, dimensions etc.




    Thanks in advance
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    Geezer
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    Re: Huge steel prod for a catapult

    Post by Geezer on Mon Oct 20, 2014 7:44 am

    Oh dear!  Just because it's old doesn't necessrily mean it's workable.  Don't try this at home.  It will deliver one shot, then fly apart.  As a catapult making friend once said: "It's quite easy to make a catapult that will shoot a stone a hundred yards. The trick is to make one that will do it a second time, and a third.' This one is not a winner. Geezer.
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    Re: Huge steel prod for a catapult

    Post by Gnome on Mon Oct 20, 2014 12:26 pm

    Wow. It looks like some baron said, "we don't need no stinkin' engineers, I can design my own siege engine!" I'm not sure this would even work once. Maybe more likely it's just an inaccurate reconstruction. Even if it was constructed solidly and with better geometry, I'll bet it's pretty inefficient, and a good chunk of the available force would be soaked up by the frame. I'd like to see that prod mounted up in a more standard crossbow-type layout, though, just to see what it could do.
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    Re: Huge steel prod for a catapult

    Post by jeep on Wed Oct 22, 2014 3:53 am

    If you went to harm somebody with this one,put him behind not in front ! Here some interesting info about "mengonet" and others :http://www.real-world-physics-problems.com/catapult-physics.html

    HeroSK
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    Re: Huge steel prod for a catapult

    Post by HeroSK on Wed Oct 22, 2014 1:09 pm

    Oh guys! Have mercy please! I am sure it can be (or used to) used for casting some grenades off the walls upon ascending crowd of enemies from behind of walls thus enabling defenders to operate under safety. The surprising part for me that I have always thought this type of bow powered machines are fictitious but apparently that was not true. I guess it is not a medieval catapult. It could be an early modern launcher that is used when there is not enough powder.
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    Re: Huge steel prod for a catapult

    Post by Geezer on Wed Oct 22, 2014 6:04 pm

    Hero:  You've missed the point.  The huge steel bow isn't sufficiently well attached, as well as being attached too far out on the limbs to be workable.  Assuming you could bend the stave enough to fling a projectile, it would fly out of the mounting downrange behind the projectile.  In my opinion, it's entirely unworkable.  Most likely cobbled together to show the tourists.  Geezer.
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    Re: Huge steel prod for a catapult

    Post by Geezer on Wed Oct 22, 2014 6:19 pm

    Whis is not to say one couldn't make a projectile-flinger based on similar principles.   And the spring itself certainly looks old.  It might be part of a big siege bow, or perhaps even a catapult.  I'm just saying this one is a piece of excrement and would be dangerous to even try to span.  It's just all wrong, as well as being flimsy.  Geezer.

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    Re: Huge steel prod for a catapult

    Post by HeroSK on Thu Oct 23, 2014 3:56 pm

    Thanks for clarification Master Geezer, I absolutely agree about this machine eventhough were an efficient catapult in the past, museum personnel hastily put the parts together which looks like quite unsafe. This is yet another example of how such artifacts are treated by unqualified museum personnel. Maybe they just preferred to rebuild it without damaging it's originality thus they did not use proper fitting for the bow.

    Also, I have never heard about crossbows with such a huge steel bow. Don't you think that such a huge steel bow would be quite slow thus rendering machine useless? As far as I know, such large crossbows, arcuballistas usually build with horn-sinew prods.
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    Re: Huge steel prod for a catapult

    Post by Geezer on Thu Oct 23, 2014 6:40 pm

    By all accounts there are extant siege bows with prods (lath) on the order of two meters wide.  In some cases, those are clearly horn/sinew composites, but some may be steel.  I don't know enough to say.  Certainly there are limits to making crossbows/catapults with huge bows.  At some point, the efficiency of such units is seriously compromised by limited strength of the materials.  That's why the famous Leonard da Vinci giant crossbow design is pretty much a washout.  It's just too big to be workable. In fact torsion-skein catapulta are much more efficient in large forms than giant crossbows. The Romans had catapultae that threw 50 and 100 lb. stones for siege work... knocking the crenelations off city walls. Of course building torsion machines would require a different level of engineering, so it's possible the local baron would find it easier and cheaper to have large crossbows built than catapultae, but in theory the torsion-bundles store more energy and deliver it to the projectile with less loss of energy.  Geezer.

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    Re: Huge steel prod for a catapult

    Post by HeroSK on Sun Oct 26, 2014 4:22 pm

    This is exactly what Heron of Alexandria (10-70 AD) writes about how torsion artillery were invented;

    "By means of the above-mentioned engine(arcuballista) of course,a larger missile could be projected a t longer range. But they wished to increase both the size o f the missile and the force o f projection. They sought to make the arms of the bow more powerful, but they could not realize their intention by the use of composite bows."


    Sad part is all the information about building such huge bows were lost. There are some later such prods but there is no way to be sure if ancient bows were built in the same manner.

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