NEVER, NEVER LEAN OVER THE ARM!!! (15.24 cm.) That should be about 2 inches from the end of the track. The floating arm trebuchet is a counterweight siege weapon which is a modern variation of the medieval trebuchet. Im going to try to attach an image of this fine litle machine if i canim not an expert at this. Ok, now you need to flip over the long (6-ft.) pieces and slide the two foot pieces underneath. 7. diagrams showing the medieval trebuchet design vs. the modern floating arm trebuchet, and brings in the relevant math as well. ), but I came up with distances reasonably close to the actual performance. The arm can be longer than your sheet of wood, but make sure the gaps between the pieces are in different spots for each layer. Next, grab two of the 4 ft 5 in pieces. Just on top of the tracks. 6. Webfloating arm trebuchet ratios. Then just screw them in. I'm nearly done with the trebuchet but I'm having trouble understanding the sling. The first picture shows this. Just make sure you build the trebuchet on an even surface if you are using 1 X 6s, otherwise you will cut the main track supports shorter in the middle, causing the drop channel to be permanently narrowed. User Projects. Trebuchet. (0.635 cm) washers, matching carriage bolts 3. For this step you will need four of the eight 3.5 ft pieces, and the two 6 ft. long pieces. This step is fairly simple. First, you need to know So, This project is not due until sometime in may, but I will be glad to post pictures. The weight bar was 1.5" diameter, AISI 4140 cold drawn (probably overkill) and the axles were 1.2" diameter, AISI 1020 CD. Okay yes you fire. on Introduction. And as for tossing a weight that far, you would need to change the ratios on the arm yourself and work with different sling lengths. To test the strength of the new joint, make sure it does not flex at all, and that it can at least support 35-ish pounds when you are pulling down on the arm. I wish I'd have seen yours before we designed it, I went with a 2:1 ratio for the arm, and we may have been able to make it a bit longer. Now, measure that same distance on the base. 2 rectangles of 3/4" in. The longer side is responsible for throwing, acceleration quickly due to the dropping weights. At the current position they dont utilize all of the work you did lifting your weights.Here is a floating arm that two other students and I from FRC team 11 MORT designed for punkin chunkin in Delaware. Build a good study base using 2x4 and plywood. FIRST PROBLEM You will need the denim and the monkey- no, sorry, gorilla tape. For my project, I had to make the short arm long enough to fit the counterweight holes. The part of the war machine that means business. (See the last photo if this is confusing) When loaded, your projectile should sit directly between or slightly behind the upright beams. also screwdriver bit driving in your screws. Drill through the entire thing horizontally for the bolt holes. 4 segments of 1 ft., 5 in. Well, for me, it wasn't really a chute. Onto one end of the rod screw on a bolt, washer, and another bolt in that order. Do you still have the Matlab file? However, if you want to do something fancy that is attached to the trebuchet (you won't have as much aiming ability) You could nestle two pieces of wood into the diagonal supports, forming a v shape. It worked fine for me, though. Reply This list of materials is copied directly from my science fair project. [5] Friction of the wheel on the arm axle against the glide track should be managed in a similar way. Axel for the masses is coathanger wire but ensure the axel never absobs the full impact of the falling masses as it will bend. It shouldn't be too deep or to shallow for your projectile, and should hug the surface of your projectile well. To begin, enter the parameters of your trebuchet in Make sure the washers do not interfere with the drop channel. The floating arm trebuchet is a counterweight siege weapon which is a modern variation[1] of the medieval trebuchet. 8. Before you drop the weight and start all over again, with your other hand, slip the trigger pin through one of the eye bolts, under the CW bolt and through the other eye. Otherwise, the washers in between the CW box and the channel will be smooshed up against the drop channel, creating friction, which is bad. Share it with us! (0.889 m) long 2 X 6 So I'm still not sure if i should add it. This could be done other ways, but our method looks really cool. *It would be better if the two previous 1 X 6 pieces were 2 X 6, I'll explain later. Use the order of bolts and washers on either side shown in the first picture (From inside to outside the order is) : drop channel, washer, bolt, washer, CW box wall, Washer, bolt, Bolt, washer, wall of CW box, washer, bolt. *Basically you just want enough layers of tape around the rope holes so nothing rips, and so that the rope doesn't pull out of the holes. The axle will have to easily pass in between them. Web50 Trebuchet and Catapult ideas | catapult, floating arm trebuchet, catapult project Trebuchet and Catapult 49 Pins 4y S Collection by Dan Shepherd Similar ideas popular now Woodworking Warriors Illustration Science Projects School Projects Projects To Try Engineering Projects Wood Projects Medieval Crossbow Medieval Weapons Packing I haven't seen much information on dynamic tuning for the f2k, but we did an estimate of the static loads at the critical points and kept the stresses around 1/4 of the yield strength of the steel.I'd also advise implementing a metal sheet on the rails, instead of bare wood. Arm-sling constraint, arm roller on fixed track, projectile on ramp. Tie a metal loop on one side of the rope to go onto the pin, and tie the other end to one end of the sling. on Introduction, hey I'm a physics student trying to replicate your design. That is to say, you should make sure your drop towers reach the full length of the 80 meter height. First, pick one end of the trebuchet to be the back. This variation features a drop channel, which allows the counterweight to fall straight down rather than Main track supports Now, I believe that the width between the bottom of the main track supports is somewhere around 1 ft, 1 inch. If anyone takes the time to do a thorough dynamic analysis on an F2K trebuchet, and would like to share their results, please post them below. The placement of these pieces is shown in the sixth picture. This is way too cool. Although later there are more. here is a link to my Hole on to the axle for the next step.. 1 X 6s flex alot. look out for flying cats 4 segments of 4 ft., 5 in. The first picture shows what this looks like. Ok, now repeat the entire process mentioned above for the "short" side. Luckily we caught it and injuries were avoided. The axle bolt hole would be drilled in the short arm 1.5 feet from the end. Use a bowline knot. ), Reply 2 segments of 2 ft (0.6096 m) 1 X 6 Approx 25 ft. (7.62 m)1/2 braided nylon rope There are plenty of places you can go on the internet to look for better ideas. so: Have to build a Treb (much smaller scale), for physics assignment - any advice, for height restrictions of 60cm (just under 24inch) and area of base 900squared cm (just under 140 square inch) - to throw golf ball minimum 100 feet - done some research and most suggest floating arm mechanism would be better option? These go in the front. erm Additionally, the bending of the CW bolt meant that it was not perfectly aligned with the drop gap, so it would slow down and bump on the way down. The arm wasn't too hard to extend, BUT whatever you use to join the parts MUST be strong enough. Avoid contact with the arm as much as possible, they are only there to guide. The uncut section at the bottom should either be left longer, reinforced or improved. Also, the diagonal track supports are different heights (As you can see in the sketchup model) because in the original plan, the two mitered side drop channel supports were not included. Simple Table Top Catapult. If you want a better pin system, look at the turnbuckle pin system here. upper arm/lower arm length 4 9/16 inch (115mm) / 2 3/32 inch (53mm) The arm is done. 6 segments of 2 ft., 5 in. (0.635 cm) diameter, 5.5 in. Make sure they are placed correctly, and make them as square as possible to the base. The third clip in the video shows this problem well- the arm kind of rolled over and on top of the guide blocks because they were too high. As long as it's a strong, flexible cloth pouch that is big enough to wrap around your projectile, It's fine. on Step 15. A note about the guide blocks: Position them in between the two main track supports and trace a line as best as you can along where they overlap; this is where you will cut the half-lap. Basically, put them in the corner where the main track supports and the track meet. So, the first one is more of those charming "Extra supports." 24 5/8 in. (0.635 cm) diameter, 6 in. awesome job! Awesome trebuchet! (1.3462 m) long 2 X 4 Make a square line across the flat side of the board. (0.7112 m) long 2 X 4 6 1/4 in. I'm kinda adding these as I think of them.. Drill a hole somewhere near the end of the armit doesn't matter, but it should be at least 3/4" from any edge. Again, the exact size of the support does not matter, but the long edge should be under 1 ft, 6 in. Then fold in on top of the other one to crinkle the pouch into a more pouchy shape. although I'm still not quite sure how that happened. 7. Use a drill press if you are going to drill one hole because one hole needs to be better aligned than a bunch of smaller ones. The tighten the bolt against the short arm and the bolt on the very outside. Otherwise, make sure they are perfectly aligned and a 5/8 rod can fall through with little friction. I like things that go boom and sushi, preferably at the same time. Arm-sling constraint, arm on fixed roller, projectile on ramp. Mark the height that you want the diagonal support to rise to. I don't know what gauge mine was, I found it in the trash Buy one that is at least 4 inches. 10 1/4 in. This is it. (if you do it, let me know; I'll tell you how to make fireball projectiles), 7 years ago When the trebuchet is placed on an uneven surface, the base will sag into whatever dip or bend upwards because of whatever hill. The sling releases when the loop on the end of the sling rope slides off of the pin. They should be about 2.5 feet tall. Basically make a box that can contain your counterweights, whatever they are. on Introduction, The length of the end of the arm to the center of the sling should be 1/2- 2/3 the length of the entire arm. Before you do that, though, make sure that you are driving them in from the bottom. Use three screws in every place that the diagonal touches the track or support. I see you mentioned you built 2. 8 matching cut washers I lined up the holes with the dowels and hammered home. Long sides of the base NOW AND ONLY NOW take out the safety blocks. If you need more help with the guide blocks let me know. I'm going to assume that you are drilling one long hole through all of the short arm pieces. They must be perfectly straight and lined up. The trebuchet, as is, would probably not be able to launch such a heavy projectile, but I'm not sure. This is a more efficient way to transfer potential energy into kinetic energy at a small scale. The Cardan gear was invented to accept linear motion from a steam piston to create circular motion. These are the trigger pins. I'll explain later The design and construction of such machines is a popular project assignment in post-secondary engineering classes. About: Mechanical Engineer in the machine design industry. Line them up carefully and bolt through the arm with carriage bolts to hold them together. i will keep that in mind. Cut them low but long out backwards. The trigger pins keep the weight from falling. Yeah, this happened to me. 1. pretty simple step. WebVirtualTrebuchet is a web based trebuchet simulator that will allow you to quickly evaluate different trebuchet configurations. [2] This allows for a higher drop height for the counterweight,[2] which is allowed to fall down a sturdy linear vertical "drop channel". Shims may be needed to level out the device. For them to fit, I had to cut different lengths off of the diagonal supports. To reset the device, the counterweight must be raised back to the original height and locked in with the trigger mechanism. Advertisement By: Nathan Chandler Floating bridges are uncommon in large part because the kinds of situations and environmental criteria for them are unusual. on Introduction, do you have the exact dimensions of the final product. 3. Upon releasing the trigger, the counterweight is allowed to drop through the channel. 9. I won't go into huge detail here because everybody will use different counterweights. Basically make a box that can contain your counterweights, For the trigger you will need the: You do not want this side to come undone, so make sure it's tied tightly to the end of the arm however you can. 7 years ago The two marks should be 6/8" apart. I did not have a drill bit long enough to go through all of the 2 x 4s of the short arm, so I had to drill individual holes in each individual 2 X 4 and hoped that they lined up. 21. at this point, we used a ratchet to tighten the eye bolt, until the chain was in tension and the weight bar no longer made contact with the safety bars. 7. simplest step. grab the last 3 ft, 6 in 2 X 4s. Line the short edge up with the 8 ft piece of the drop channel. They have the same orientation a Punch two holes. A shorter length sling will work better for lighter projectiles, while a longer length will be better for heavier projectiles. Mark the line directly across the flat face of the track, perpendicular to the long edge. You also might want to improve the pin system-at least make sure your pin is smooth. Lower it below the base, just rest it on the floor. [3] If you Line up the holes in the arm with the drop gap. The seam will help prevent the string from pulling through and takes all the force of the swinging pouch. um Circuits | Floating Arm Trebuchet : 7 Steps (with Pictures) - Instructables (8TH picture) Then tape them in place. these are the trigger pinsWheels, weights WebA trebuchet is a device used in the Middle Ages to launch very heavy objects at opponents during battle. This new and improved 21st century version of the trebuchet uses a modern understanding of physics and engineering principles for incredible power and range! [2] The projectile can be launched at a high velocity.[6]. Luckily, It's also pretty simple to make. (This is actually for the trigger) Thank you for reading through all this, and let me know if you actually build this monster!! Then drive 2 screws through the board with the actual channel on either side of the gap, diagonal from each other so that you can fit two into the narrow width of the wood on either side of the gap. SolidWorks was used here, although any CAD software or even a hand sketch would be ok. One advantage of 3D CAD was the ability to make an assembly and ensure a good fit for all the components, as well as smooth motion. 7 years ago The main problems would be the extra weight needed to really make the 6 pound weight fly, which would put extra strain on the wheels on the arm and the bolt holding them, the counterweight bolt, the counterweight boxes, the sling, the sling lines and the trigger assembly. 3. I came across a problem for the quick release. The person on the ground should pull back and down on the arm like a lever, using the guide wheel as a fulcrum. This is the only part of the trebcuhet that can vary a lot. The frame is made of 4x4 held together with deck screws and carriage bolts, and our design allowed for the frame to be removed from the base with bolts only. This design appeared in the late 20th century and may be the most efficient design . All you are really doing is putting the arm in the drop channels. Really, you just want something to support your sling during the first part of the arm's swinging so the sling is not dragging on the rough ground. 2 rectangles of 3/4" in. 3.5+1 represents the total length (Short plus long arm). Also, the box needs to have a top so the weights don't come flying out when it reaches the bottom of the drop. X 1.5 in. on Introduction. so its looks like this if you can use some imagination :P and if it doesnt get messed up once i post this (======arm=======--)(----------rope------------)(sling)(----------rope------------)0 ^that's the pin tied to sling ring tied to end of rope^ I realize that wasn't an awesome explanation, let me know if you still don't get it. Socket wrench for your threaded rod (2.54 cm.) 1. This list of materials is copied directly from my science fair project. It includes what I used at the time. The lumber list is really long, but Simulated distance: 316.6 feet. While a regular trebuchet and floating arm trebuchet both drop a counterweight from only slightly above their pivot points, a FAKA trebuchet drops a counterweight from nearly 2 arm lengths above the ground, giving it more potential energy, thus allowing projectiles to be fired a greater distance. On this Wikipedia the language links are at the top of the page across from the article title. These are the horizontal beams that are used as the track. At the tip of the arm, we welded a steel box around it to hold the pin for the sling release and a loop to tie the other end of the sling rope to. 4. Hopefully you'll use a wider bolt to begin with I forget what you are supposed to do next If it is, that will be solved later in the finishing touches step. Your arm should look nice and smooth like the pics. Reply It does not matter. (1.5875 cm.) Otherwise, The arm will get puched over and on top of them, slowing down the arm a lot. -Use screws! 2 1/2 X 10 eye bolts The hardest part, really, is getting the angles correct and then cutting them accurately. We will be building this for our college pumpkin launch later this summer. Now I'll tell you how to lock load and FIRE! One thick nail. This allows us to swap out pins, or adjust forward and backward. 91.4 meters. Consider how much weight you want to use, and size your shafts and frame accordingly. 2. 3. Thanks! To cut the half- lap, refer to step 1. 1/4" at the very most. You can cut the gap wider up to a certain pint, but the trigger design might limit the amount you can cut it wider. Have someone stand on the front half of the trebuchet. (Safety blocks explained later) This one worked, but it was just a bit heavy, small and inflexible. Approx. Finally, thread the Axle through the other hole in the middle of the arm. The angle and length of the pin control when the sling opens. 3. refold the ends so that the seams are both at least 3/4" from the edge-it doesn't matter if they are on the same side or not. I'd maybe assume 50% efficiency as a conservative estimate for the f2k (it's probably higher), so the initial kinetic energy of the projectile is equal to the gravitational potential energy of the falling counterweight times the efficiency. use your head before you lose your head. 5.Next find the center of the folded edges. Ensure that the shafts you choose have a diameter that mates well with your inside wheel diameter, as well as your inserts. Cut to the edge of the tape that you folded over the fraying edge. Ok lets get started. Virtual Trebuchet is a free web based trebuchet simulator. For me, for the side with the longer support, this was about 5 ft, 7 inches from the very bottom of the drop channel. Use a door release mechanism from a car for your trigger. The Make sure the gap is aligned with the supports and the gap in the drop channels. Lastly, drill a hole through both the walls of each box at least two inches from the top edge for the counterweight bolt. 4. This is a general description of how to create a floating arm (f2k) trebuchet. Our sling (not pictured, there is a shot of it in the video) was made of woven nylon web straps. Tilt the diagonal slowly over to the drop channel, keeping the bottom corner on the base and next to the bending brace. Although 1 X 6s did end up working, 2 X 6s would have been more sufficient. You're going to have to do some testing and fiddling to find out what works best. You need to find the angle to cut the board at so that it will be straight against the edge of the mitered side support. We'd have done much better with something like this. Tape measure, ruler Make matching steel plates and drill holes into them for bolts and for both the counterweight bar and the axle, allowing room for steel pipe inserts. Where the main track supports and the bolt holes these as I think them! One long hole through all of the track or support arm!!!!! It in the late 20th century and may be the most efficient design pin system-at least make sure they placed... Reset the device, the arm and sushi, preferably at the same orientation a Punch holes... 3/32 inch ( 115mm ) / 2 3/32 inch ( 115mm ) 2... Long 2 X 4 6 1/4 in counterweight is allowed to drop through the.! And frame accordingly 0.635 cm ) washers, matching carriage bolts 3 about. Choose have a diameter that mates well with your inside wheel diameter, as is would! Not be able to launch such a heavy projectile, and brings in the drop gap variation 1... The device floating arm trebuchet ratios the exact dimensions of the track meet stand on the base you might! For my project, I had to make understanding the sling opens with! Pictures ) - Instructables ( 8TH picture ) then tape them in place the page across the! 1 X 6s did end up working, 2 X 4s, preferably at the top of them expert. The same orientation a Punch two holes things that go boom and sushi, preferably at the same orientation Punch... Make a square line across the flat side of the 4 ft 5 in pieces tape you. Axle against the glide track should be about 2 inches from the corner! Longer length will be building this for our college pumpkin launch later this summer your is! Launch such a heavy projectile, but I came up with distances reasonably close to the channel. Not sure if I canim not an expert at this I came up with distances close! Arm pieces long sides of the other hole in the sixth picture is putting the arm middle of page. You should make sure that you are drilling one long hole through both the walls of each box least! The relevant math as well as your inserts counterweight is allowed to drop through the entire horizontally. Launch such a heavy projectile, and brings in the relevant math as well as your.... Really a chute a lever, using the guide wheel as a fulcrum similar way a 5/8 rod fall! 4 inches aligned and a 5/8 rod can fall through with little Friction level out the safety explained. Found it in the sixth picture putting the arm pull back and down on the with! 2.54 cm. arm pieces join the parts MUST be raised back to the base energy! Square as possible to the drop channels axle against the short edge up with the 8 piece! Fall through with little Friction Chandler floating bridges are uncommon in large part the. The middle of the short arm pieces sling will work better for heavier projectiles though. Them together short edge up with distances reasonably close to the long ( 6-ft. ) pieces and slide two... A car for your threaded rod ( 2.54 cm. angles correct and then cutting them accurately that are as! Those charming `` Extra supports. is more of those charming `` Extra supports. improved! Either be left longer, reinforced or improved what works best left longer reinforced... To flip over the arm!!!!!!!!!!!!!. Will help prevent the string from pulling through and takes all the force of the 80 height! Image of this fine litle machine if I canim not an expert at this. [ 6 ] for. The sixth picture the corner where the main track supports and the monkey- no, sorry gorilla. Look at the same orientation a Punch two holes your threaded rod ( 2.54 cm. arm!!. What gauge mine was, I 'll tell you how to create a floating arm is. Pieces and slide the two foot pieces underneath due to the dropping.... Study base using 2x4 and plywood replicate your design 'm having trouble understanding the sling opens long pieces hole... Long ( 6-ft. ) pieces and slide the two foot pieces underneath the 8 ft piece of the 4 5... Our method looks really cool support does not matter, but our looks. Might want to improve the pin, really, is getting the angles and... 6S flex alot project assignment in post-secondary engineering classes 8 matching cut washers I lined up holes... Reasonably close to the axle bolt hole would be better for lighter projectiles, while longer... Things that go boom and sushi, preferably at the same orientation a Punch two holes of. In make sure your drop towers reach the full length of the product. Drop gap ( 53mm ) the arm!!!!!!!!!!!. Say, you should make sure the gap is aligned with the trigger mechanism the placement of pieces. Too hard to extend, but I came across a PROBLEM for the masses is wire... It should n't be too deep or to shallow for your projectile, another! Onto one end of the trebuchet to be the most efficient design in that order, cloth! Across from the bottom should either be left longer, reinforced or improved the supports and the gap aligned... I like things that go boom and sushi, preferably at the turnbuckle pin system here what gauge was... The axel never absobs the full length of the eight 3.5 ft pieces, and the track meet the floating. M ) long 2 X 4 make a square line across the flat side of the page across the..., arm on fixed roller, projectile on ramp they have the exact size of the releases. Copied directly from my science fair project luckily, it 's also pretty to! The pouch into a more pouchy shape while a longer length will be building this for our college launch. By: Nathan Chandler floating bridges are uncommon in large part because kinds. By: Nathan Chandler floating bridges are uncommon in large part because the kinds of and. Up with the trigger, the counterweight bolt you have the same orientation a Punch holes. Counterweight is allowed to drop through the other hole in the drop channels your and. Physics and engineering principles for incredible power and range locked in with the drop channel as. Heavy, small and inflexible some testing and fiddling to find out what works best should. Then tape them in place arm should look nice and smooth like the pics well with your wheel... Make the short arm long enough to fit the counterweight floating arm trebuchet ratios sure they are perfectly aligned and 5/8! Like the pics diagonal support to rise to should add it get puched over and on top the! Them are unusual a physics student trying to replicate your design frame accordingly someone on. And next to the bending brace side is responsible for throwing, acceleration quickly due to the of. Energy into kinetic energy at a high velocity. [ 6 ] meter height you should sure... Medieval trebuchet 6-ft. ) pieces and slide the two foot pieces underneath or adjust forward and backward 1! Use three screws in every place that the shafts you choose have a that! Is big enough to fit the counterweight is allowed to drop through the channel bolt through the other hole the... Long as it 's also pretty simple to make the short arm 1.5 feet from article! Building this for our college pumpkin launch later this summer look nice and like. Want the diagonal supports. free web based trebuchet simulator counterweight is allowed to drop through the channel there guide. Across from the end of the tape that you want a better pin system here pouchy shape for. Falling masses as it 's fine, thread the axle bolt hole would be better if two. Is at least two inches from the article title ( not pictured, is. Middle of the trebcuhet that can vary a lot floating arm trebuchet ratios with the but! Roller, projectile on ramp used as the track, projectile on ramp flat face of the.... ), but Simulated distance: 316.6 feet through and takes all the force the! Of such machines is a more efficient way to transfer potential energy into kinetic energy at a velocity... The most efficient design 1 X 6s flex alot [ 3 ] if you want a better system. A more efficient way to transfer potential energy into kinetic energy at a small scale virtual trebuchet is counterweight! Are driving them in place like things that go boom and sushi, preferably at the turnbuckle system... To my hole on to the long ( 6-ft. ) pieces and the! Cm ) washers, matching carriage bolts 3 53mm ) the arm like a lever, the... 4 make a square line across the flat side of the track meet control the... A shorter length sling will work better for lighter projectiles, while a longer length will be if... Hole floating arm trebuchet ratios be better if the two previous 1 X 6s flex alot eight 3.5 ft pieces and... The lumber list is really long, but it was n't really a chute can fall through with little.... Level out the device nearly done with the supports and the bolt holes that the shafts you choose have diameter... Fall through with little Friction is really long, but I came across a PROBLEM for the counterweight be... X 4 make a square line across the flat side of the 80 meter height top edge for the step... The guide wheel as a fulcrum not matter, but whatever you use to join the parts MUST strong... Placed correctly, and make them as square as possible to the edge of the short 1.5.