[Daniel Bertrand]

I have a working 1/2 scale machine that we took Punkin Chunkin last fall. Need to fix it up this summer and I'm looking forward to getting some more throwing in. It's 33 feet tall and when it's in prime it throws 16lb bowling balls 250 yards with about 2,000lbs of weight. On wooden axles.

I am always interested in finding other people with trebuchets and similar interests in siege engines. Especially anyone studying this stuff. I want to make a full scale eventually but not sure how that is going to happen.

Lots of videos on my YouTube channel: https://www.youtube.com/channel/UCXIB2SLLkMPzr6BjajJe_DA?

The picture is us winding it down last October.

I'm new to this forum, I apologize if there is already a thread about this.

[Dan Howard]

Very cool. I made one for the kids using meat skewers and popsicle sticks. I'd love to make a bigger one.

[Dan Howard]

I've read some studies suggesting that more energy can be delivered to the projectile if the trebuchet is on wheels. As the arm swings over, the frame rolls forward, which lets the counterweight fall vertically for a little longer while also shifting the stall point of the arm to a more vertical position.

Edit: Here is a video explaining it.
https://www.youtube.com/watch?v=KpFTyE-wiNo

[Matthew Amt]

[Matthew Amt]

I should add that when I first saw that Nova show, I was so amazed that I ran for my Legos and built a trebuchet, so I could test it myself! The difference between wheeled and unwheeled (with a fixed counterweight) was impressive. But the swinging weight design achieves the same effect without the wheels.

Matthew

[Dan Howard]

[Daniel Bertrand]

Hey, that popsicle stick one you made is cool! I actually inherited some craft sticks and glue from a class project a year ago and kept thinking I would make something like that. Finally realized I would never get around to it so I gave the sticks and glue away to someone else who would use them.

Having a big treb is awesome, but it's also a pain. I need four people to operate it at full weight. There is a balance of size somewhere for the average joe. Maybe something that throws baseballs or tennis balls. If I wind up with a desk job though I will definitely need to get some kind of gumball throwing trebuchet.

And yes, I think the hinged box does the same thing as the wheels. There aren't many medieval illustrations of these things on wheels, but there are definitely a few -- I think wheeled trebs were a minority. I'm not sure anyone has done some legit practical testing on this matter though. Would love to see some good experiments with a decent-sized model between wheels+fixed weight, wheels+hinged weight, and no wheels+fixed weight, no wheels+hinged weight. All other variables the same.

[Daniel Bertrand]

Whoa, I forgot about that Tom Stanton video. That was a great experiment. There you have it. I guess wheels do make it throw farther because they synchronize the stalls later and make the throw more efficient.

Probably not going to add wheels to my treb anytime soon though. Not sure how that would be feasible on my frame design. It's a lot safer for me to have the frame just staked to the ground.

I suppose most medieval trebuchets weren't on wheels simply because it's so much easier to just put them on the ground. Not sure. The difference in performance maybe wasn't worth the extra effort in design and construction?

[Roger Hooper]

Does this one count? Made by Elastolin in Germany, back around 1960.

[J.D. Crawford]

[Dan Howard]

[Daniel Bertrand]

[Daniel Bertrand]

[Roger Hooper]

[J.D. Crawford]