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sharpiefan
07-14-2018, 08:34 PM
https://www.youtube.com/watch?v=-gn2RGPqe_A

johnw
07-14-2018, 08:45 PM
That's an interesting approach, but aren't they supposed to be better with wheels?

LeeG
07-14-2018, 08:57 PM
that was excellent. Seriously, what could be more fun.

skuthorp
07-14-2018, 11:05 PM
I was reminded of some of the theory behind coaching fast bowlers, especially the release point.

(he needs a bigger backyard)

johnw
07-15-2018, 02:13 PM
aka ballista
Nothing like.

https://img1.cgtrader.com/items/78788/28d6d0c2bb/ballista-3d-model-max-obj-fbx.jpg

amish rob
07-15-2018, 02:17 PM
Yar. And the mangonel or onager is the torsion type.

Peace,
Robert

switters
07-15-2018, 02:21 PM
http://i281.photobucket.com/albums/kk221/switters_bucket/IMG_20140601_090512868_zps97aecce5.jpg (http://s281.photobucket.com/user/switters_bucket/media/IMG_20140601_090512868_zps97aecce5.jpg.html)

lots of variables in that concept. keep your trebuchets simple and portable and stocked with waterballons at all times.

LeeG
07-15-2018, 02:31 PM
I wonder if there is a trebuchet society

amish rob
07-15-2018, 02:32 PM
Don’t use a trebuchet to throw toilets. Unless you manage to get a permit.

Especially if you have a trebuchet large enough to throw said toilets.

They go FAR!

Peace,
Tie The Sling Through The Bowl ;)

johnw
07-15-2018, 02:41 PM
They can have my trebuchet when they pry it from my cold, dead fingers.

sharpiefan
07-15-2018, 02:44 PM
.....so do pianos :D


https://youtube.com/watch?v=V6zmMWfzv38

StevenBauer
07-15-2018, 02:46 PM
The trebuchet I helped build was pretty big and a little crude. The throwing arm was about 25’ long and the weight was a big wooden basket full of rocks. The first time we “fired” it we used a 1 gallon jug of water as a projectile. There were about 20 people standing around to watch. We pulled out the pin and that 8 pound projectile went straight up about 150’.
I’ve never seen 20 people scatter so quickly.
Fine tuning was adding a foot or so to the sling.

Gib Etheridge
07-15-2018, 03:34 PM
There was no calculus used in this build.

Old Dryfoot
07-15-2018, 03:34 PM
I've put together a few desktop trebs using a 2" ball bearing as the counterweight. Nothing fancy, but hard on the drywall if you used the right projectile, usually a smaller bearing.

I'd like to have a go at a larger, floating arm trebuchet, something in the 100 pound range.


https://www.youtube.com/watch?v=l7UAvmFZRIc

Corvida
07-15-2018, 03:52 PM
That's a whole lot of effort to solve an already solved problem, in a less efficient method. The optimization is simple. Drop the weight in as straight of a line as possible, which is accomplished by putting the whole thing on wheels. Rails being the most efficient, however they are difficult to aim.

David G
07-15-2018, 03:56 PM
There was no calculus used in this build.

<snort>

Is the fascination with such weaponry a variety of preparation for a time of HeadsOnPikes??? <G>

Paul Pless
07-15-2018, 05:15 PM
that was excellent. Seriously, what could be more fun.

cannons

LeeG
07-15-2018, 06:49 PM
cannons

ok, but the neighbors might notice.

Paul Pless
07-15-2018, 06:57 PM
i've had the police show up before when firing cannons and mortars on my land
they always show up all hell bent on seriousness
when they find out you're firing off civil war artillery they get all excited and politely ask if they can watch :D

LeeG
07-15-2018, 06:57 PM
i've had the police show up before when firing cannons and mortars on my land
they always show up all hell bent on seriousness
when they find out you're firing off civil war artillery they get all excited and politely ask if they can watch :D

you are kidding, really? what size?

Durnik
07-15-2018, 07:01 PM
^^ Alabama, Paul?

Paul Pless
07-15-2018, 07:43 PM
Napoleon, 12 pounder. Not mine, its owned by some friends. My brother and I own a Coehorn - its way cool, it fires so slowly that you can follow the projectile during its flight.

LeeG
07-15-2018, 08:06 PM
Napoleon, 12 pounder. Not mine, its owned by some friends. My brother and I own a Coehorn - its way cool, it fires so slowly that you can follow the projectile during its flight.

I’d like a small cannon

Paul Pless
07-15-2018, 08:14 PM
I’d like a small cannon

M1841 mountain howitzer. You can buy one of these for less than $2K. Even without special tools a committed person could build one for about half that. . .

19504

Art Haberland
07-15-2018, 08:28 PM
You guys need to go to Delaware in the Fall during "pumpkin chunkin"


https://www.youtube.com/watch?v=1iy7y8KgkwY

amish rob
07-15-2018, 08:31 PM
Or come to our Renn Faire. Matchlocks and trebuchets. And jousting!

Peace,
Robert

Pitsligo
07-15-2018, 09:24 PM
I’d like a small cannon

Not sure how well it throws projectiles, though:

https://farm6.staticflickr.com/5581/31305540666_2e67537f37_c.jpg


Or come to our Renn Faire. Matchlocks and trebuchets. And jousting!

Which one? (I used to work the CA RenFaire circuit.)

Alex

Garret
07-15-2018, 09:27 PM
I’d like a small cannon

There are folks here in VT who make cannons that are "beer can caliber". They shoot a beer can filled with cement. They do competitions for accuracy & such.

Here's a different, but similar type cannon youtube I found:


https://www.youtube.com/watch?v=cVXpTm8Q2DE

amish rob
07-15-2018, 09:32 PM
Not sure how well it throws projectiles, though:

https://farm6.staticflickr.com/5581/31305540666_2e67537f37_c.jpg



Which one? (I used to work the CA RenFaire circuit.)

Alex
Kearney Park. A few years ago they started Medeival Combat, too. It is hilarious fun.

Peace,
Robert

Chip-skiff
07-16-2018, 12:44 AM
When I was fascinated by archaic weaponry, I built a ballista.



https://users.ece.cmu.edu/~koopman/ballista/pics/ballist2.gif

Mounted the leaf spring from a Crosley on a 4 x 4 with steel cable for a string, cocked with a boat winch. The bolts were 18" pieces of rebar. Power Plus!

I mounted it on brother's little red wagon (he was pissed). He tattled to my Dad, who came out just as I shot a piece of rebar completely through the cinderblock wall out back.

Many words were said.

Then I took it apart.

Old Dryfoot
07-16-2018, 01:32 AM
https://www.youtube.com/watch?v=PKA2eUneyj4

Old Dryfoot
07-16-2018, 01:46 AM
Put on your pocket protectors.


https://www.youtube.com/watch?v=K7mB5iftarQ

switters
07-30-2018, 04:21 PM
http://i281.photobucket.com/albums/kk221/switters_bucket/IMG_20180728_191948_zps3sutxlmh.jpg (http://s281.photobucket.com/user/switters_bucket/media/IMG_20180728_191948_zps3sutxlmh.jpg.html)

I was properly motivated to blow the dustwebs off of the Mark III, and take it out for a beer Saturday.

Old Dryfoot
07-30-2018, 06:17 PM
^ Have fun storming the castle!

ThomRose
07-30-2018, 06:45 PM
I've put together a few desktop trebs using a 2" ball bearing as the counterweight. Nothing fancy, but hard on the drywall if you used the right projectile, usually a smaller bearing.

I'd like to have a go at a larger, floating arm trebuchet, something in the 100 pound range.


https://www.youtube.com/watch?v=l7UAvmFZRIc

When he makes the basket, then I will be impressed.

Stiletto
07-30-2018, 06:58 PM
M1841 mountain howitzer. You can buy one of these for less than $2K. Even without special tools a committed person could build one for about half that. . .

19504

Interesting that it is called a howitzer. My understanding of the term was that they fired at a high trajectory. Does the barrel on that one raise up?

LeeG
07-30-2018, 07:49 PM
There are folks here in VT who make cannons that are "beer can caliber". They shoot a beer can filled with cement. They do competitions for accuracy & such.

Here's a different, but similar type cannon youtube I found:


https://www.youtube.com/watch?v=cVXpTm8Q2DE

I like that. “where’d it go?”, “down that way”