Trebuchet CATAPULT Project/Worklog Updated 12/12/06 Please COMMENT

2 day update. This is the last 2 days of work sorry been busy so couldn't update till now. Damn blackout and essay's.


Ok lets start with the cutting of the bolt rods. This I don't even know the name of it but its like a giant dremel. What we are cutting are 6ft bolt rods at 1/2 inch. These will be holding the base together which you will see latter.


My friend Bryan Fisher getting a go at it. Lots of sparks .


Unfortunatly there are some serious burrs on the bolt rod after it is cut so after some quick dremel work its ready to go . Hurray for more sparks.


The finished product a 8 inch bolt rod with the washers and bolts on it the wood will be inbetween it.


Here is a picture of the base put together roughly at the end of day 1.


This was at the end of today but you can see how the bolts are going in. There is going to be more wood on that which is kind of hard to explain but if you look at the design schematics a while ago you can tell.


Here is my rough design drawn out. What you see there is the center vertical beam the other 2 have not been put in yet due to time.


Another pic of the bolts that are squeezing one of the 3 vertical collums.


Here you can see the holes for the bolts that will go thru all 3 vertical support pieces but due to me being lazy and not wanting to hold up all 3 pieces of wood I just took a pic of the hole. Tom I will show you the finished product.


Here is us drilling the holes with all 3 pieces in but I think it is hard to see the thickness which is 8 inches of wood. I will have better pics tom I promise.


Here you can see the base just about finished using mostly scrap wood hence the many different colors.


Here for size comparison the axel will be at the top of those beams.


Here is another size comparison and seeing how everything is sized up and this pic has almost everybody working on this project but Gabe, Josh and Emma


Gabe using the circular saw to cut the angles for the foward and back braces. Had to make 16 cuts for 8 beams at 8 feet long with 45 angle cuts.


Here you can see us fitting the foward back supports.


And another pic we were only fitting the front two as we had them all cut. But in the final design there will be 4 of them 2 on either side of the middle vertical support beam.


Weighed the box also which came out to about 80 pounds. Not very accurate though as it was an old scale and it was odly balanced. Gives us a ballpark though.


Us hard at work unfortunatly since the support beams arn't finished and bulked up yet they are kind of flimsy and need to be held up.


Our camera man for the documenty being a little goofy. Kind of funny though just shows how big the box is.

WELL YEAH BIG UPDATE but we are comming along and we should be finished by the middle of next week. And as always any comments or suggestions are welcomed.

 

http://www.instructables.com/ex/i/535B13C242DD1029AC23001143E7E506/

One of these "I saw this and thought of you" moments

Joel

 

SWEET MAN my blue tack will be a little bigger though . Nice job the paper clips don't bend. I mean you got a lot of batteries there.

 

Got a lot of work done starting to really take shape.


Here is a picture of the bolts going in. Sorry kind of blurry stupid crappy camera.


Here is the better image and the basically finished vertical collum. As you can see three vertical collums with spaces between them.


Here is another view which is easier to see.


Here you can see the front and back supports and how they are connected. They are on either side of a base beam sandwiching it between them.


Here you can see it connected to the vertical collum. No holes for bolts drilled in yet so we using rope to hold it together for the time being.


Here is a frontal view of the front back supports and you can see how they are connecting into the treb.


Here is a side view where you can see the front and back supports now attached to the vertical collum.


A frontal view. The one on the right we didn't have time to put the front and back supports in so we left it as is and just roped it together.


We started on the throwing arm here our wood is being glued together and is left to set over the weekend.

Yep lots getting done should be done by next week hopefully. Not much more to do. Will be cutting the axel probally next time.

 

I was worried at first that some of those planks might twist under the weight, but not you have made them triple thickness I'm sure that won't be a problem.

 

Great stuff, makes me want to make one too.

One thing is bothering me though... For the supports (theese) i would definately have done what we swedes call a "halving" instead of cutting them at 45 degrees. Like so:



That would give you more wood acting on the bolts and straight supports making for a more secure joint. I don't think this will lead to a "i told you so" moment, but you never know...

 

Yeah but this will hold as i bulked everything up way past what I actually need. The way I did it is a much simpler build that is why I choose this way. I did a smaller treb using those joint connections and they broke on me durring firing. So I am staying with my simpler design.

 

Sorry For not updating for a while havn't had much time but got lots done. And launch date set but no testing done yet so that might change.


Remember this guy from way back. This is the first piece I got the bench press getting ready to get cut.


This is it after it got cut. I was cutting these ring that were welded on off and the other I dremeled off. I will get better pics of it latter.


The piece that was cut off this is scrap as the bench press was about a foot too long so had to make it shorter. And there you see the excess.


Here you can see us working on the treb with both sides done.


Without a person in the way lol


A frontal View I know its bent in slightly that is going to be fixed.


Here you can see the top of the vertical support collums where we put spacers in. The 1 inch hole is going there.


Here you can see the one inch hole for the axel and another bolt rod which hasn't been bolted yet.


Here is us working on the throwing arm. The 1 inch hole is being cut.


There are 8 of these bolts in the treb evenly spaced. Now we only used 1 every once in a while to prevent making as many holes in the wood. The arm is held together with glue too.


Here is a slanted view of the throwing arm where it is reienforced for the axel. The wood on top of it isn't going to be there just had writing on it to tell everybody not to mess with it.

So yeah that is all the pics I got taken as I said been very busy needing to finish this. One thing to note we got the throwing arm on the base and it swings fine. And the leaning in was fixed by the axel going thru the top.

Note the demonstration day was set for June 19th but I will be launching this week to test it out.

 

Thread revival I know, but I'm curious as to whatever happend to this thing? Success? Dismal failure?

 

Yeah, I forgot about this! Updates!! I reckon the original poster isn't active on this forum anymore though..

L

 

He's around

 

Hey guys sorry about not doing anything for a while. If you heard in the news about the tornado that ripped through New York. Guess what it hit. Thats right I live in Sleepy Hollow and it had a direct hit on it. I have some more pics of it actually put together and painted. Unfortunatly only had time to test it with 200 pounds of counter-weight with a 10 pound lead ball. Threw that about 250 feet though before tunning.

 

Oh also if you want to see the aftermath I think I have one or two pictures. Sorry about leaving you guys hanging for so long with insurance attempts and college applications been a little busy.

As for rebuild or any of that I might do it again sometime possibly while in college but the build team is totally dismanteled going different directions. The 2 seniors in the class both went to college one actually to Brown University. As for the rest of us we are going seperate ways personally I am applying to Cornell University for engineering while other are applying to Harvard, Duke, MIT which she got into lucky, Dartmouth, Brown again and Stanford. Yeah really smart group of friends which helped me with this considering it was an AP Physics class myself actually being the dummest of them.

If you guys have a different idea for a project post here or send me a message I might plan on attempting something for a senior project after college apps or summer project. As you can see I am willing to do almost anything.

WILL BE POSTING A FINISHING UPDATE UP TO DESTRUCTION JUST HAVE TO COLLECT PICTURES

 

Did you happen to take any pics of the test firing?

Bring on the update

 

Wait a second. Sleepy Hollow = by the Hudsen, near the Tappan Zee? If yes, tornado, what tornado??

Wherever you are in NY, this is your task...

you must deliver 4 lego blocks to me. Whether it be by trebuchet, sewage submarine, missile, etc, that is your task. Well, no missiles. =P.

Seriously though, how about a BEAM robot which tracks down a light source and then launches a tethered solar cell ball at it to help it charge faster.

Basically, it would be a mini-rebuchet with automated pre-launch guidance. Have trebuchet scan environment. Light up a target, have trebuchet detect target and then fire. The tethered part seemed cool but more like a last resort recharging measure. eh, it's late and I'm tired. It's not like you'd really expect me to make any sense. If I ever have time, this is a project I might consider. Hmm. A mini-trebuchet would be great for launching LED "throwies". Nothing says WOO like bright lights flying through the air.

 

Yeah Sleepy Holow by the hudson look in the news. I got some pictures of what it did to my school too. It was durring the beggining of the summer. If I can find it I got this crazy pic shows the treb where I was testing it in a crumple heap and behind it you see a hole in the woods from the tornado taking out trees. Yeah in the news might be said as tornado in Tarrytown but it was crazy. Just my luck to have a natural disaster that like almost never happens in NY destroy it oh well it was fu though.

I have a couple pictures of testing none though with an actual projectile being thrown due to the fact I was busy when we were doing that to take pictures. But I got a lot of pics will post it latter today.

 

Hey guys, I'm also making a trebuchet!

Mine is for an A level Physics investigation, it measures approximately 30cm in height and uses masses up to 3kg. Range is approximately 3 meters using a rubber ball.

 

Cool yeah that is awsome I made a small one like that I advise for cw something like pennies cause it is dense and easy to mannage. POST SOME PICS and if you have any questions ask me I will be happy to answer.

 

I may attempt a trebuchet historically they could fire 100's of meters so I bet a scaled version could be made to fire a dozen or more.

 

FINAL UPDATE

Ok this is going to be long sorry that it took so long. Here goes.

Last time we talked I had just finished putting the thing together inside and dissasembly went great here are a few pics and explanations of transport.


As you can see the van is back and we put the two colloms with front and back support struts already attached. The base was also transported ontop in this fashion.

As for the inside of the van all our supplies and the counter-weight box was moved with the weights.

Here is my friend brad helping secure the top as well as how crowded the van got. We had to make about 3 trips to move it all.

Due to it being uneven the straps weren't enough so we had to ride outside the van and physically support it. Luckily it was just a short ride up to the football field.

I was holding from the back standing on the back bumper and decent aerial pic on how the collums fit.