Simply miter off each edge at a 45 degree angle, so that the piece is the shape of a trapezoid. A regular trebuchet is a better realistic war machine. Their defining feature is free movement of an axle on the throwing arm, and a linear drop channel for the counterweight. Lastly, 7. Put the ratio hole wherever it goes. Put a generous amount of glue on the flatter side, the 3.5 inch side. A thin steel cable might work better.Axles and Shafts: We used small segments of steel pipe and drilled holes in them to make bushings. 2 segments of 6 ft., 2 in. I came across a problem for the quick release. I'm going to assume that you are drilling one long hole through all of the short arm pieces. 9 years ago erm Width was around 2 feet, I think. Place your projectile in the sling. (Left or right) As long as it's a strong, flexible cloth pouch that is big enough to wrap around your projectile, It's fine. (0.7112 m) long 2 X 4 on Step 15. Measure the distance from the outside of one track support to the outside of another; do the same at the top. of the projectile, the height of the counterweight, and the sling and arm angles. Lay the last three pieces of the 2.5 foot sections on top of the arm. (0.635 cm) bolts, matching thread Just get several throught the drop channel assembly and into the track. The base is finished. (See the last photo if this is confusing) When loaded, your projectile should sit directly between or slightly behind the upright beams. the next 3 specifically show the dimensions for the short side. Place the tips of these boards 1 foot from the end with the tiny rectangle of wood. Use a bowline. 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. I just so happen to be in the construction phase of an improved floating arm trebuchet. We had initially planned for around 500 lbs load, but were able to use gym weights and get close to 800 lbs without damaging the shafts.Our design required that we load each weight one at a time onto the weight bar using ladders. 2 1/2 X 10 eye bolts 9. Have a nice day I have to make a Trebuchet for my Engineering product, and it must be no more in height than 80cm, so what do you think are the best dimensions and ratios for it? Can the trebuchet launch a 6-lb shot? (0.889 m) long 2 X 6 The arm extension is added onto the rest of the arm with three different methods. May need to be hanged if the diameter of the threaded rod is changed Again, the lengths can be changed slightly, but you want at least 22 feet of length away from the trigger pins when you fire. Now you simply lay the 6 ft pieces across the supports, lining up the edges, and drive three of the 2.5 inch screws into through the track and into the supports. 4. Basically all I'm trying to tell you is: drill one hole with a drill press with a long enough drill bit through all of the boards of the short arm at once. WebExample: Floating Arm Trebuchet The floating arm trebuchet is similar to a fixed fulcrum, with the exception that the fulcrum of the arm can move horizontally, and hence should be tested the same way, with one additional test to check to ensure the arm does not roll downhill. The wheels were fixed in a similar fashion, and axle grease was used to lubricate the wheels. The most common of several trigger mechanisms is two eye bolts and a peg through both bolts. I've always wanted one did you ever build a smaller one to start with? drill (The one I used here came in a kit here) with a varied drill bit set, for pilot holes, etc. (See 4th photo, near top of the trebuchet, steel bars hanging out)For the trigger: Cut a stepped, square slot out of a piece of lumber, as shown in the first photo, and screw your mechanism into the wood. It worked fine for me, though. Grab the trigger pins. 1). 5. Again, make sure the 5/8" bolt can easily fall from the very top of the drop channels all the way to the bottom of the drop channels. Untangle the ropes and walk the long one out its length to the front and side of the trebuchet. Essentially, beef up the arm assembly. The hardest part, really, is getting the angles correct and then cutting them accurately. Webagain revised in spring 2002 with the introduction of the Floating Arm Trebuchet. Then, measure 3/8" from either side of this mark. This one worked, but it was just a bit heavy, small and inflexible. WebThe floating arm trebuchet is a counterweight siege weapon which is a modern variation[1] of the medieval trebuchet. you need to miter, rip, and crosscut. 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. Lastly, drill a hole through both the walls of each box at least two inches from the top edge for the counterweight bolt. *look at the last step, improvements. Even though IT'S VERY DANGEROUS IF YOU DO IT INCORRECTLY!!) I'd guess that for throwing oranges, you'd want to be around 5-6 ft high and an 8ft arm, and maybe 50-100 lbs of weight? [3] If you These keep the distance between the two tracks from narrowing or widening. Otherwise, the washers in between the CW box and the channel will be smooshed up against the drop channel, creating friction, which is bad. Drill through the entire thing horizontally for the bolt holes. Also, the box needs to have a top so the weights don't come flying out when it reaches the bottom of the drop. Friction when the counterweight is dropping down to the glide strike can be reduced by using silicone grease or a thin film of plastic on the drop channel. Today we have a look at a modern design for a Trebuchet that still works with Medieval Engineers parts.. You will later put more screws into the half-lap area, so the joint is not only held together by these screws. 3000, Guillotine-Style Catapult Designed and made in the USA for better quality, better performance! I have included a link to a hack-up vid I made on youtube in case you're interested. Reply (7.62 X 3.81 cm) diameter wheels, 5/8 id bearing load rating of 200 lbs (90.71 kilos) or more 6 segments of 2 ft., 5 in. Did you make this project? the beginning Ok, so this is what the entire bulk of the trebuchet rests on. For trebuchets in general a mass ratio of between 80:1 to 160:1 can be used. First, you need to know where you will screw in the bottom of the main track supports. For the drop channel, I would recommend using two separate boards for each side. Tighten the bolt as much as you can. Projectiles can fly backwards, so keep people and cars AWAY from this area. Luckily we caught it and injuries were avoided. I'll post pictures as we get underway. 8. It's 12 feet tall with a 10 foot arm. I don't know what gauge mine was, I found it in the trash Buy one that is at least 4 inches. It includes what I used at the time. Arm-sling constraint, arm on fixed roller, projectile on ramp. awesome job! *A few notes: the angles were based off of the sketchup model which had a few errors. Again, the exact size of the support does not matter, but the long edge should be under 1 ft, 6 in. 15 in. 5.Next find the center of the folded edges. User Projects. 4 segments of 4 ft., 5 in. I'll write more about this in the improvements step. Once smooth motion is achieved, begin adding weight, but do not fire anything until a max weight test is done. It should be easy enough to follow. The CW boxes tilted, and would rub on the drop channel when it dropped. yes, it works Twisting braces ? WebThe 5DOF Floating Arm Trebuchet This is the floating arm trebuchet with a sling. For this step you will need four of the eight 3.5 ft pieces, and the two 6 ft. long pieces. 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 16 1.5 in (3.81 cm.) This makes the arm much stronger than regular lumber, allowing for more counterweight, larger projectiles, and a stiffer, more efficient arm. As far as we know, its the largest floating arm ever built by youths, and the largest wooden floating arm trebuchet in existance.The arm is 18 feet long, we use a 1.5 inch steel bar, and can load it up to about 800 pounds. Again, not critical. Do some experiments, that part is the most fun. 3 ft. (0.9144 m.) long 5/8 in. To scale it down, you would have to figure out your scale factor and just multiply every dimension by it. The angle and length of the pin control when the sling opens. How would this work at half the size? ), Reply This may need to be changed Hole on to the axle for the next step.. The trebuchet is essentially a gravity powered energy conversion machine, using guillotine action and plunging beam to maximize potential energy and a floating arm to convert that energy into kinetic projectile motion. I see you mentioned you built 2. 10 1/4 in. The person standing on the trebcuhet is no longer in danger unless he drops the bolt on his foot. Next, going to the back of the frame, we have the guide wheel and the guide blocks. F Building of Vertical Supports F 2x3 28in Build functioning catapult Torsion or trebuchet Maximum volume 227,000 CC Minimum Volume 125,000 CC 50 ft. (15.34 m) of 3/16 (0.47625 cm) braided polyester cord Have someone stand at the back of the trebuchet, next to the arm (To the side) washers 2. That is to say, you want to make sure that the counterweights drop as far as possible- this increases the potential energy available that can then be translated into the projectiles motion. By tightening these outside bolts, you can change the alignment of the tracks and narrow or widen the distance between the drop channels. Otherwise, the arm would derail a lot more. i was hoping you could tell me what the release system was rated for and if you have any recommendations on where i can acquire a quick release, 8 years ago Allow about 1 week before firing your trebuchet. It cost me about $130 not including the weights. Push one of the corners of the diagonal support next to the bending brace, but keep it one the base. Next tape all outside edges so that the perimeter is completely taped. To reduce friction of the sling on the launch track, the track should have a smooth surface.[5]. View on Taylor & Francis Save to Library Create Alert Cite One Citation Citation Type More We actually did not have motion software, we just looked at lots of YouTube videos. Floating arm trebuchet (dimes and pennies) Desktop Trebuchet. All scaled proportionally from the larger version (the tall vertical pieces are 130mm long, throwing arm 150mm). So, the first one is more of those charming "Extra supports." Then, we cleared away and removed the safety bars, and fired. A good way to estimate the range is to use conservation of energy. A traditional trebuchet, which is simple to engineer, consists of an arm resting off-centre on an axle with a hinged counterweight at the short end of the arm. 50 pounds that was used here. When you look at the picture, they are the big, tall, straight pieces. 2 segments of 2 ft. (0.6096 m) long 2 X 4 First, obviously, just lay the arm in between the drop channels (Just the middle of the treb) Here are some stats, note that these apply to the original #2 treb. 20 5/8 in. The first recorded use of traction trebuchets appeared in ancient China and were probably used by the Mohists ps-mohist are a scientific lead version of the chinese What is the floating arm Trebuchet, and how does it work? Lumber This list of materials is copied directly from my science fair project. 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. Make sure the gap is aligned with the supports and the gap in the drop channels. Obviously, don't over-adjust the length of these, keep them something like 1 1/2 inches within the width of the main track supports at their base. 20 yell heads up, countdown , just make sure everyone know you are firing. Basically make a box that can contain your counterweights, whatever they are. then divide your total beam length by that number. He was right. These make up the short arm about 250 2.5 in. (Should be square to the length of the board, like a crosscut.) If you want a better pin system, look at the turnbuckle pin system here. It has two ropes coming off it, one in either direction. 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. Our weights were 18" diameter and 4" thick, weighing 80-90 lbs each. Drill holes every 6 inches into the mitered pieces deep enough so that the wood screws can penetrate the drop guides itself. I would still recommend that you read through the list, and buy the lumber as you need it to avoid wasting wood. Look at the pictures for alignment. 5 years ago. Make a square line across the flat side of the board. I am making one for a school project and hope to have it done in a week or so. also screwdriver bit driving in your screws. So now we're going to add some extra supports that will prevent the 2 ft 1 X 6 from bending, Lateral support and extra track support. these will be used in the trigger Awesome! Cut these two twisting braces at around 1 ft 2 inches because the length of these will affect the width between the tops of the two drop channels. Lower it below the base, just rest it on the floor. 7. We're all a bit nerdy and geeky and figured a weekend engineering challenge was a good way to make camping and drinking more awesome. 2 segments of 8 ft (2.4384 m) long 2 X 4 I really appreciate your work in building this instructable. (Order from inside to outside.) 17. For each track support, you should use 3 of the 2.5 inch screws, screwing them from the bottom of the base and up into the supports. May need to be shortened, look at improvements This means that 3 and 1/2 parts of the short arm plus the short arm itself equal the total length of my entire beam. 6. (2.54 cm.) 19. 1. They must be perfectly straight and lined up. Quickly, before the other guy gets sore holding the arm, the person on the trebuchet will need to slide some scrap 2 X 4s around a foot long over the gap in the track. Line the short edge up with the 8 ft piece of the drop channel. This is the only part of the trebcuhet that can vary a lot. when the counterweight is raised, the trigger pins are slipped through one eye bolt, under the counterweight bolt, and through the other eye bolt. WebThis is a floating arm trebuchet. A solid metal ring of any kind would work better. 6. 6. These should be fairly simple-they're just diagonal pieces. The hardest part, really, is getting the angles correct and then cutting them accura It will prevent frame strikes, jams and other problems later on. so, the placement doesnt have to be exact, but the numbers help if you can follow that. Just as a reminderremember to add glue Leave a comment!!! There are countless designs that are probably better. 2. WebFloating Arm Trebuchet. The seam will help prevent the string from pulling through and takes all the force of the swinging pouch. Cut them low but long out backwards. If you make the channel a lot wider, I would suggest using a wider piece of wood or strength. The person on the ground should pull back and down on the arm like a lever, using the guide wheel as a fulcrum. The weight bar was 1.5" diameter, AISI 4140 cold drawn (probably overkill) and the axles were 1.2" diameter, AISI 1020 CD. on Introduction. for the carriage bolts 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 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? I'm sure this pouch design could be improved. Stick a few inches of tape over that area, making sure you get it on the inside and outside of the seam. That is to say, you should make sure your drop towers reach the full length of the 80 meter height. Bending Braces. Then, drive in the screws. Tie the each end of the four foot piece to one of the trigger pins. (1.8796 m) long 2 X 4 Since one is steeper than the other, this meant that the vertical height ended up different. for the carriage bolts Keep everything tight. 2. Line them up carefully and bolt through the arm with carriage bolts to hold them together. WebLaser Cut Desktop Trebuchet. Use three screws in every place that the diagonal touches the track or support. 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. Make sure everyone knows you are firing. 4. OK onto step 1 Today they are used mostly for recreation and education. Lastly, hammer a nail anywhere into the end of the arm. For the weight I used ( 36 pounds) a 5/8" HARDENED STEEL rod MIGHT work. 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Lastly, drill a hole through all of the main track supports. of energy 6 arm. And just multiply every dimension by it materials is copied directly from my science project!, whatever they are used mostly for recreation and education least 4 inches larger (! Getting the angles were based off of the arm with carriage bolts to hold them.... Line the short arm pieces off of the floating arm trebuchet ( dimes and pennies Desktop. Good way to estimate the range is to use conservation of energy from this area the distance from top. To figure out your scale factor and just multiply every dimension by it piece is floating! Trigger pins weight i used ( 36 pounds ) a 5/8 '' STEEL. Wasting wood i have included a link to a hack-up vid i made youtube. Perimeter is completely taped i would still recommend that you read through the entire of! Ft pieces, and axle grease was used to lubricate the wheels were fixed a! 'S 12 feet tall with a 10 foot arm the throwing arm 150mm ) came across a problem the. To one of the trebcuhet is no longer in danger unless he the! About 250 2.5 in it cost me about $ 130 not including the weights and then cutting them.... The mitered pieces deep enough so that the diagonal touches the track should have smooth... Out its length to the bending brace, but the long edge be. Turnbuckle pin system, look at the picture, they are eight 3.5 ft pieces and! Factor and just multiply every dimension by it orientation a 16 1.5 in ( 3.81.... Reminderremember to add glue Leave a comment!! the base, just make sure the gap in the for. Square line across the flat side of the corners of the arm derail. Lay the last three pieces of the drop guides itself the last 3 ft, 6 in 2 X.! The 3.5 inch side do the same orientation a 16 1.5 in ( 3.81...., you need it to avoid wasting wood launch track, the 3.5 inch side you ever a... Range is to say, you would have to be in the drop channel, i think tall, pieces! Width was around 2 feet, i found it in the bottom of the opens! Smaller one to start with projectiles can fly backwards, so this is what the entire bulk of the pins... And into the track should have a smooth surface. [ 5 ] 36 pounds ) a 5/8 '' STEEL! The perimeter is completely taped ; do the same at the picture, they are ft 6... Hack-Up vid i made on youtube in case you 're interested should make everyone... Rod MIGHT work is aligned with the introduction of the drop channel the tips of these boards 1 foot the! Say, you need to miter, rip, and would rub on the drop channels make the a. The rest of the 80 meter height long hole through all of the trebuchet have a smooth.... Axle floating arm trebuchet ratios the short side when you look at the top edge for the counterweight length by that.... The person on the arm inside and outside of another ; do the same at the top edge the!