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X-treme Onager

New low price!


Designed and made in the USA for
better quality, better performance!

Now made from top-quality solid oak non-toxic, formaldehyde-free plywood for a more dimensionally stable, stronger, and less expensive model than if made from natural wood.

Modeled after the Roman Onager, this torsion-based machine can hurl golf balls and tennis balls over 50 feet!



This modern design for an Onager uses the exact same principles as the ancient Roman war machines. It is capable of hurling small stones, golf balls, walnuts, eggs, tennis balls and even potatoes from 20 feet to more than 50 feet! It all depends on how much power you build into it and the weight of your projectiles. Precision crafted of high quality hard wood, the kit contains everything you need to build a working model in one evening.*

The advantages of this new design are:
  • Double cross-grain frame for added strength.
  • Higher skein and arm rest allows for longer slings.
  • The arm can travel farther, well beyond the vertical limit of a traditional onager.
  • A soft arm arrestor eliminates hard impacts between the arm and the frame.


The ONAGER (also called a Mangonel) uses a bundle of twisted ropes (called a skein) for real torsion power. This torsion engine is so powerful, a full-sized machine can hurl a bowling ball almost 1/4 of a mile!

The finished model stands 17" long, 14" high and 12" wide. The kit is precision crafted from top-quality engineered hardwood plywood and includes a working winch and real leather sling-pouch.

The detailed instructions are complete with diagrams, photos and tuning tips so you can get the most out of this fun project. All parts are pre-cut, pre-drilled and can be assembled to a finished model in one evening.

We've put a lot of time and effort into making this kit as easy and complete as possible. It's a fun way to learn about history and engineering!


* Golf ball and tennis ball missiles are not included.
* Can throw over 50 feet when properly constructed and tuned. Your performance may vary.

WARNING! This is a representative model of a real ancient military weapon. It contains a fast moving arm that can cause injury if you make contact when firing. Use only under adult supervision.



Tools required:
Scissors, Glue, Ruler, and a utility knife. Sandpaper is optional.

Assembly time:
For a Master carpenter doing a sloppy job: about 2 hours.
A person with no kit building experience being extremely meticulous: about 10 hours.
The model in these photos was built by Ron Toms in about four hours.

Assembled Size:
- Height: 14"
- Length: 17"
- Width: 12"


Range:
- 20 to 50 feet with golf balls as projectiles, about half that with tennis balls. (Optimal range assumes a well built and well tuned machine)

Shipping weight: 5 lbs.
Box dimensions: 24" x 12" x 4"



Quantity pricing info:
0 to 4 kits, standard price.
5 to 9 kits, 10% off
10 or more kits, 15% off

Orders of $200 or more get FREE ground shipping!

WARNING! This is a representative model of a real ancient military weapon. It contains a fast moving arm that can cause injury if you make contact when firing. Use only under strict adult supervision.


* Can throw 50 feet when properly constructed and tuned. Your performance may vary.
* Golf ball and tennis ball missiles are not included.
* Actual item may differ slightly from the images on this page.
* X-treme Onager is a trademark of RLT Industries.



$59.00
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    Price: $59.00
    Minimum age: 14
    Availability: In stock.

    Buy Now or Add To Cart
    Item code: 10301

Notes:
Why should a kid
build a catapult?

Because the world needs good engineers and scientists, and because the kids who will grow up to become engineers and scientists need a way to get hands-on experience with physics, math and engineering.

In this age of 200-plus channels of TV, the Internet and computer games, kids are also spending far less time building tree houses, tinkering with engines, or designing downhill racers. We believe those are important skills to have. They help form the basis for good problem solving skills and an innate understanding of the real, physical world that you just can't get from a computer game, no matter how good its physics simulation software is.

Ballistic motion was one of the key players in the development of the science of physics. The word "engineer" even originated as the builders and designer of Siege Engines

Why is a budding engineering student expected to take a year or two of calculus in high school, but she isn't expected to have any real-world experience in building or working with machines and materials? Pencil and paper (or computer screens) are only one part of the learning experience. Where will she apply all of the stuff she learned in geometry and trig? Without physical projects to touch, feel and see, the lessons become abstract, their utility questionable.

A catapult project gives students a chance to see that science and engineering really can be fun, and it's a lot more than just numbers on paper. The real payoff for an engineer is in the field, where she can see and enjoy the results of her ingenuity. And it may seem counterintuitive, but engineering projects not only help kids learn math and science, they are also great at getting kids back outdoors, away from the massive over-exposure to video games, TV and the Internet.

Why all this interest in getting kids to study science and engineering? Because it's important to our society, and it's great mental cross training regardless of what field of work the kids eventually go into. Most people develop a sense for what they want to do in life while they are still in high school or even earlier. A catapult project is fun and interesting enough to inspire some kids to study the science behind how they work, and then go on to become the engineers and scientists of tomorrow.