schmanman's trebuchet

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paaiyan
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Tue Aug 21, 2007 10:51 am

jackssmirkingrevenge wrote:
paaiyan wrote:Monty Python! Hecks yea.
That and the Trojan Rabbit lol

[youtube][/youtube]

:D :D :D
I love you jack! You're my hero! That is such an awesome movie.
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jackssmirkingrevenge
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Tue Aug 21, 2007 10:57 am

I love you too, even though your mother was a hamster, and your father smelt of elderberries :roll: :D
hectmarr wrote:You have to make many weapons, because this field is long and short life
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Modderxtrordanare
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Tue Aug 21, 2007 11:37 am

I fart in your general direction. Go away, before I taunt you another time.
Spudding since '05. Proud waster of plumbing and plumbing accessories.

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paaiyan
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Tue Aug 21, 2007 11:38 am

Modderxtrordanare wrote:I fart in your general direction. Go away, before I taunt you another time.
You mixed up the lines.

"I fart in your general direction, your mother was a hamster, and your father smelt of elderberries."

"Is there someone else eup there we can talk to?"

"No, now go away or I shall taunt you a second time."
"Who ever said the pen was mightier than the sword, obviously, never encountered automatic weapons."
-General Douglass MacArthur

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jackssmirkingrevenge
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Tue Aug 21, 2007 11:48 am

hehe I love the subtle French conversations.
French Soldier: Un cadeau.
Other French soldiers: A what?
French Soldier: A present.
Other French soldiers: Oh. Un cadeau.
Other French soldiers: Oui oui.
French Soldier: Allons y!
Other French soldiers: What?
French Soldier: Let's go!
Other French soldiers: Oh.
:D
hectmarr wrote:You have to make many weapons, because this field is long and short life
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joannaardway
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Tue Aug 21, 2007 1:47 pm

jackssmirkingrevenge wrote:ballista
trebuchet
Not quite, eh?
That's not a ballista. That's a ballista!. *Ahem*
(Yes, that is the correct quoting. "This is a knife" is a misquote. Check here if you like. [6th quote down])

The ballista you showed there was a very small ballista.
Additionally, that trebuchet is many times larger than any that would have been practically used for siege warfare.

Quoting directly from J.E. Gordon's "Structures - or why things don't fall down":
Nevertheless, the palintonon or ballista was a most effective device for land warfare...

Thus the greatest potential energy stored (for the trebuchet) probably did not much exceed 30,000 joules. The same amount of strain energy could be stored in about ten or twelve kilos of tendon. Thus, even a big trebuchet probably disposed of about a tenth of the energy of the palintonon. Further more, the efficency of energy conversion seems to have been much lower.
At best, the trebuchet could probably only make a nuisance of itself by lobbing big stones over a fortress wall. Any assault on heavy masonry would have been ineffectual...

Thus, much of the kinetic energy stored in the arms is recovered...

It transpires that rather surprisingly, the energy transfer process is in theory virtually 100% efficent.
In otherwords, practically the whole of the strain energy which was stored in the device can be converted into the kinetic energy of the missile.
Translating that, a ballista had ten times the potential energy of a trebuchet.
A ballista is close to 100% efficent, but a trebuchet must have a very significant amount of energy left in the counterweight and arms at the end.
So, I was right! In theory, the ballista was over 10 times more powerful.

Also consider this. That 30,000 joules figure if you apply a generous 50% efficency, a trebuchet has less kinetic energy than you can get from the .50 BMG cartridge.
I know the .50 BMG is at the powerful end of a "small arms" cartridges, but you certainly wouldn't endanger many stone walls with it.
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jackssmirkingrevenge
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Tue Aug 21, 2007 8:44 pm

joannaardway wrote:The ballista you showed there was a very small ballista.
Additionally, that trebuchet is many times larger than any that would have been practically used for siege warfare.
That's not a knife! It is, it's a cheese knife, it will make light work of this bris!

By your reasoning, I can say that a bicycle is more powerful than a car by comparing a massive bike built for 175 people to a Robin Reliant, simply because it's more efficient I didn't look it up in percentage terms, besides it's very subjective, but you catch my drift ;)

I've never seen an antique example of a ballista the size you posted, and the fact is that medieval trebuchets existed that could hurl in excess of a ton - I'd like to see the size of the ballista that could achieve this - so in practical terms, regardless of theoretical efficiency, the ballista was the small and relatively accurate "point target" weapon while the trebuchet was the "heavy artillery" used for bombardment.
hectmarr wrote:You have to make many weapons, because this field is long and short life
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Hotwired
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Wed Aug 22, 2007 9:27 am

It still doesn't compare to a trebuchet in terms of power.

Ballistas were medium-small siege weapons and intended to be used against infantry or light fortifications.

Trebuchets chucked lumps of anything from ~50-1500kg specifically for turning serious fortifications into rubble.
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jimmy101
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Wed Aug 22, 2007 10:35 am

J.E. Gordon's:
At best, the trebuchet could probably only make a nuisance of itself by lobbing big stones over a fortress wall. Any assault on heavy masonry would have been ineffectual...
I don't think so. A big ass treb could pound a full scale castle wall to rubble in a couple days. In the Nova on building trebs they only managed to hit the castle wall mockup once. But the wall was pretty well pulverized by the single hit. A couple more hits in the same area and the wall would be breached.

I don't know how anyone in their right mind could compare the energy in a big ass treb to a 0.50 cal. The 0.50 won't do anything to a feets thick masonry wall. A big ass treb will.

Another advantage of a treb is that it is an indirect fire weapon. It can be used effectively to launch annoying things over walls (or hills, or buildings) and it can be fired from behind a baracade that completely protects the front of the weapon and the crew.
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joannaardway
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Wed Aug 22, 2007 2:21 pm

jackssmirkingrevenge wrote:I've never seen an antique example of a ballista the size you posted, and the fact is that medieval trebuchets existed that could hurl in excess of a ton - I'd like to see the size of the ballista that could achieve this.
Actually, that's a pretty small ballista still. The roman seige ballistas were easily twice that size again.

Perhaps you might be interested by this BBC program that ran a few years back. Their results weren't too successful, but it's interesting nonetheless:
Part 1
Part 2
Part 3
Part 4
Part 5 (You can see the size of their replica at the very start of this section)

For two engines of equal size, the ballista is easily more powerful than the trebuchet.
Actually, by the bicycle/car reasoning, comparing a miniature ballista to a vast trebuchet is quite illogical on the other extreme.

You are all arguing here with a highly respected textbook written by a well-known professor. What I am expressing is only data taken from this - if you have a problem, I suggest you are arguing with the wrong person.
Novacastrian: How about use whatever the heck you can get your hands on?
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...I'm sorry, but that made my year.
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thespeedycicada
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Wed Aug 22, 2007 2:42 pm

i have to agree with joanna my ballista can fire farther than my trebuchet as can my onager wich operates on the same principles (torison springs) of the ballista.Although ballistas cant really fire projectiles good for breaking down fortress walls.
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joannaardway
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Wed Aug 22, 2007 2:59 pm

It does seem surprising, but the ballista was the weapon used by the Roman legions against stone walls and defenses.

In medieval times, they decided to scale up the trebuchet several times in order to make it feasible to use it for the same purpose, but this was only because with the fall of the Roman empire, the technological regression that came with it made it impossible to produce ballistas.
Novacastrian: How about use whatever the heck you can get your hands on?
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...I'm sorry, but that made my year.
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jackssmirkingrevenge
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Wed Aug 22, 2007 3:30 pm

You have yet to show us a ballista that will hurl a 1500kg projectile... The point that's being argued...er...discussed here is not what was more powerful conceptually, but the fact that the most biggest trebuchet ever built was more powerful that the biggest ballista ever built ;)
hectmarr wrote:You have to make many weapons, because this field is long and short life
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joannaardway
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Thu Aug 23, 2007 8:56 am

I don't deny that a trebuchet can easily outsize a ballista and therefore can do more damage by pure momentum, but on a hobbist's scale (which is where the dicussion started) you'll get a much more powerful engine from a ballista than a trebuchet - that is what I have been saying.
Novacastrian: How about use whatever the heck you can get your hands on?
frankrede: Well then I guess it won't matter when you decide to drink bleach because your out of kool-aid.
...I'm sorry, but that made my year.
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jackssmirkingrevenge
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Thu Aug 23, 2007 9:16 am

can't disagree with you there, in that case

Image

:D
hectmarr wrote:You have to make many weapons, because this field is long and short life
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