This video is sponsored by brilliant.org check the link in the description for a discount on your first subscription. Hey guys
I'm Nate welcome back to the workshop today
We're going to be building a desktop version of a seized weapon called a trebuchet this applies to us a pretty basic
I have here a 1/2 inch thick piece of plywood which is about 2 feet by 2 feet, and this will actually be extra
We'll have some left over after our build
We've got some very strong string this will be used in a sling portion of our trebuchet
I've got a thin metal rod
Which are going to use as the axle if you don't have any metal rod available you can make this work
Just fine with a piece of wooden dowel
I'm using some scraps of leather for the pouch on our sling if you don't have leather any strong cloth will work
Just as well
I have an eye bolt a couple of nuts and a stack of washers that will become the counterweight in our trebuchet
We have an assortment of nuts and washers that will be used to help space our throwing arm in between our two support posts then
We also have some of these fruit candies, and these are going to be our projectiles
We'll also use a tiny eye hook and a small brad nail to attach our sling to our launch arm the design for this trebuchet
Is actually very basic and easy to make from this board we're going to cut four pieces
There will be a base a launch arm and two side support pieces
To be cutting out the pieces I do have a jigsaw and a circular saw if you don't have those
Most any kind of saw will work, but it might take a little longer
Let's start by measuring and cutting the piece of board that we'll use as the base for our trebuchet now for reasons that will become
Clear later. Let's make our board just over three and a quarter inches wide
I promise I have a good reason for it being this width but it's a bit of a surprise
Music
Cutting sound
With the base cut the next step is to cut a one inch strip at least 16 inches long
My board is about two feet long, so I'll cut my 1 inch strip 24 inches long and then trim it down to 16 inches
Cutting Sound
Music
Cutting sound
With our base in our launch arm cutout we now need to cut out the two side supports
These are going to be two triangle-shaped pieces that are tall enough that at 10 and 1/2 inches we can add the axle
It's not terribly important that you match any particular shape with these supports, but it is good
If it extends to the left and right of the axle a little bit to add support
Now all of this will get removed and I'll have to sort of A shaped support pieces
Cutting Sound
Now with all four of our pieces cut to the right size shape and sanded
Let's drill holes in the two supports and the swing arm on the swing arm we want the hole to go right through the center
Of the board about four inches from one end
Drilling sound
With our two support pieces and our swing arm attached together with our axle we now want to permanently attach our support pieces to our
Base to make sure we don't crack our base board. Let's pre drill our holes before we add the screws
Drilling Sound
The basic construction shape of our trebuchet is now assembled
Let's trim off the axle, so it's not sticking out and good six inches out of the way
Our throwing arm is now attached in between the support posts
But you can see that it will easily slide from side to side
This is where we'll use those nuts and washers to help keep it centered right in the middle
Hammering
We've got some nuts and washers on our axle it still spins beautifully
But now it has no play to either side as a next step
Let's attach a hook to the back of our throwing arm that we can use to hang our weight from now
I've driven that I hook almost all the way down the loop is now touching the wood
To be sure we have a way to attach our weight now
Let's use a small pair of pliers and try our eye hook open a little bit
So it's more of a hook and less of an eye
To make sure it's open far enough. Let's see if our large. Eye bolt can fit down into the gap
Looks like it fits. Just great now to make our weight
Let's take our eye bolt load it up with washers and add a few nuts on the bottom to hold them all in place
We now have a nice weight try hanging that on the end of our trebuchet and see what happens if we let go
Well partly, that's what we wanted to happen I guess we need to close the hook over our loop once
It's attached before I close that on though I'm looking at the speed of this
And I think it would be better if we could get it to launch just a little bit
Faster than that that's not a ton of speed on there
So I think I want to increase this weight by a little bit these are very small thin nails that are designed to go in
An electric nail gun, but I'm just gonna use them as a little bit of weight today
So I'm just going to take several of them put them together and tape them onto our weight that we've already made
All right that is considerably heavier almost double the weight that I had before
Let's see if our launch speed seems to have changed at all
That's a much better swing around I like that way more all right
Let's attach our weight and then close off our eye hook, so they can't fall off on back
And boom
Beautiful
Launches and it doesn't fall off
The two things we were looking for now we need to add the sling that will connect to the other end of the swing arm
Let's use our string and the material we're using for our pouch to make the sling before we attach it to the swing arm
When you're choosing a string for your trebuchet you want to find one that you can't easily break by pulling on it
Now for our trebuchet to launch the way
it should one inside of the string should be permanently attached to the swing arm and the other one should come off as
It's swinging through the air
so let's drill a small hole in the top of our swing arm and tie one end of our string to that and then we'll
Make a small ring and a little peg coming out of the top
To make sure that the other string can release when it's supposed to
Positioning our sling we want the pouch to be at the very end of our track
And then we'll lower the swing arm down, and that's where we know we need to attach it
Let's just make a mark in our string for how long we want it to be while it's tied around the hole
To make our hold and release mechanism
Let's add a small peg at the top of the swing arm made from a very small nail and a little ring on the end
Of the other string now this nail does not have much of a head
But we want a smooth peg with no head at all, so let's get a file and take the head off of this
So it's all smooth the head of our nail has now been completely removed
It's really just more of a smooth metal stick
We now need to drive this small Brad nail
Down into the wood until there's only about half an inch maybe a centimeter of it sticking out
That looks like it should work pretty well now
Let's use a small washer as the ring to attach to the other side of the string
This will slip over the peg and should release nicely when our sling is at the top of its arc
We can now see how our trebuchet loads and will launch as the weight pulls it down the pouch will swing up and around
The washer then we'll slide off of the post and it should take our projectile and launch it through the air
At this point I think we need to do a test run
I have this small piece of candy which I've sort of smushed into a little bit more of a ball shape this will be our
projectile, we'll load that into the pouch bring it all the way down and
When I release the pouch this should fire one note about this before I fire it
Currently the nail at the top of the swing arm is pointed basically straight up the angle of that nail has a lot to do
With at what point the washer will slide off of it, so it's entirely possible that right now with the angle
It's at it might shoot too straight up or even launch early. Let's find out
All right first test fire in three two one
Wow
Well, it didn't shoot straight up it shot at just about a 45 degree angle
Which is kind of what we want so it's working pretty. Well. We just need a better launch space
Guess let's take this outside and see how far it goes now. We let this go in three two one we oh wow
I worked pretty great
23 23 feet not bad. Let's see if we can do it again
Firing in three two one
whoo
Launched one and a half 19 and a half last time 23 this time 19 and a half, so it's not perfectly consistent
But that's still pretty good wonder anyone firing a full-size trebuchet back in the Dark Ages
Ever said we as they launched it they were missing out on a great opportunity if they didn't
Working pretty good our trebuchet is launching these candies a good distance
I think we've shown that the counterweight on the trebuchet is working pretty well, but I also want to try
Taking this up to another level
I want it to really launch these things far, and I have a thought for that all right
That was pretty cool this thing has some pretty good distance on it, but there's a little modification
I want to make I want to add some real power onto this and I guess I could just keep adding more weight
I think there is a limit. I think it's around
130 times the weight of the projectile is how much weight you should have on the back for ideal launching
But I want to see what happens if we add spring power to it
Not just a weight
But something really pulling on the string as hard as it can to add a little bit more power to our trebuchet
We're going to try using a spring loaded rat trap this thing will pull on our trebuchet arm with a ton of power
Hopefully it doesn't break it, but we should be able to get some incredible distance and maybe some larger projectiles using this
Now to make sure the rat trap is pulling the string the right direction
when it fires our trebuchet
Let's add a small eye hook down at the bottom that will help direct the string so it's pulling in the same direction as gravity
instead of pulling sort of sideways
Okay, I've got the eye bolt installed, and I offset it a little bit
so it's not quite in the middle of the path this I'm hoping will allow the
Firing mechanism to still pass through a whole trebuchet without getting caught on the eyeball as it swings
We can see now that with the eye bolt in place no matter what angle
I pull this string at it's always pulling down on the back of the trebuchet arm the same way I can pull it straight up
And it still pulls straight down
So I pull it out in the direction that the rat trap will be we have a great angle
Pulling the same direction as gravity, so I'm hoping this will work pretty well
All right here we go let's take this tape off load it properly and see if it'll fire
All right now our trebuchet is not loaded at the moment because I think if we fire it indoors
We'll just end up breaking stuff, but we'll see if we can get it to fire even though. There's no projectile in it
Now to set it off
I have some popsicle sticks wrapped in some paper towel
Wrapped in some tape, and I'm doing this because I don't want to tape my fingers
But this is fairly soft and should be able to activate the trap. Let's see how well this works
Hmm, I snapped the string it might be a little too powerful and need some reinforcement
We've got some much thicker stronger string
I'm gonna try tying that in the same way attaching it to both the trap and hook on the back
And hopefully this will be up to the challenge
Our stronger string is now attached to the trap and the hook on the back
Let's try launching it again and see if we can get it to not break apart this time
There's still no projectile in it, but it should work as a test here goes Wow
Yeah, yeah that launched
Very quickly very powerfully I'd say that'll do it
And we're back outside our rat trap is attached to the trebuchet the string is attached to the swinging arm and the trap is set
So now let's load up some ammo
And hit the trigger and see what kind of distance we can get on this bad boy all right here goes three two one
Where'd it go
Did you see where it went I didn't even see
Well guess we'll just have to try again three two one
I didn't keep a better eye on it
We had two shots where we launched them out of the trebuchet
but we couldn't really see where they went they launched off so quickly that we lost track of them and
Even looking at the high-speed footage of the camera we couldn't really see where they were going because they left the frame pretty fast
So I actually had my cameraman stand behind the trebuchet just to watch and pay attention to where the shot was going
Because we couldn't find it and we finally managed to track where one launched
After we launched it and I was amazed at where it ended up how far back is that thing?
There it is there we go. This is where it landed
so the trebuchet way over there and
So it's possible that our first couple shots went about as far as well, and they just have blended it into the grass so far
But I am amazed
I'm amazed at how far that went like I thought we'd get maybe two or three times as far and well
Maybe that is two or three times as far
It just seems like a lot if our first shot was 20 feet
Then this is now I have to measure it's gonna take a while because it's a long ways, but see how close one
almost
73 feet
That's pretty great
3 2 1
This thing is working great with the counterweight on it
We get shots 20 to 25 feet away with the rat trap on it. We are getting shots up to 80 feet away
that's pretty nuts this is certainly the kind of project that deserves to be scaled up something bigger and
Possibly with projectiles that are on fire if you wish that learning science
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