Hurricane balls and tornado ball with air compressor

This is a video of me spinning up hurricane balls with an air compressor. I have gotten them faster (I estimate this run got up to about 10,000rpm) but it is still very cool. The second part of the video is some random thing I made when I was bored. It just spins a marble really fast inside the container. I know it's not very exciting :P haha please comment and rate! hm...the video won't embed so just go here.

Topic by Electroinnovation 8 years ago  |  last reply 8 years ago


instructions for knex ball tower? Answered

Hi, i have all the pieces to the knex big air ball tower, but i don't have the instructions. can anyone tell me where i can download them?

Question by the poodleo 7 years ago  |  last reply 7 years ago


The differnences between an big air ball tower ball and an motorized madness balmachine ball? Answered

I'm thinking of buying more knex balls at knexusergroup. The only balls I have right now are 8 motorized madness ballmachine/ loopin lizard balls. The one's at knexusergroup are the one's from the big air ball tower. So my question is: Are they the same and if not what are the differences? Thanks for reading this. -sathothy

Question by sathothy 6 years ago  |  last reply 6 years ago


Airsoft v.s Paint ball

Many paintballers disrespect airsofters and vice versa. which is better??? (i play both and i enjoy both of them)please post some pros and con for each sport.A.S=airsoft P.B=paint ball Pros and cons for 6mm paintballs:Pros: Can be used in any gun if 6mm, can see if hit. most biodegradable Cons: Sometimes burst in the gun and mess up you're gun fore ever, don't all ways burst. It is like for every paintball that doesn't burst, 10 6mm paintballs don't burst. 3X more expensive than normal BBs airsoftpros: cheeper ammo & guns. reusable ammo. grater gun design freedom. guns available at walmart and most sports stores, AS guns look like real guns -Co2 cost only about 50 cents you can airsoft anywherecons: cheating is easier, more painful, Co2 can only be used once, you can't tell if someone was shot, biodegradable ammo hard to find and only available in .2 & .25 gram bbs (most guns work best with .12g ) paintball pros: more fields then A.S. easy to see when hit, less pain full games end a lot faster allmost all paint balls are biodegradable cons: ammo not reusable more expensive need large c02 tanks you need a huge open space and no dangers of damagni property and often have to pay to use fields airsoft at parks and large aeraswana add to this list just comment (please do so nicely this is ment to help people to decide between the 2)heres a tally of preferences / = 5 tallys |=1tally P.B/|A.S / ||||

Topic by i make shooting things 11 years ago  |  last reply 1 year ago


knex ball tower? Answered

Can you use for the knex big air ball tower lift different balls than frome that set?

Question by Sorunome 8 years ago  |  last reply 8 years ago


Tennis Ball Cannon

Alright, so ive been into making all sorts of cannons whether they are pneumatic or hairspray, and recently I've been wanting to build a pneumatic tennisball cannon. i came across halve a dozen empty fire extinguishers, i am still deciding if i should use one as the chamber. i am using an electronic sprinkler valve and a 2 1/2" barrel i am also getting a 12 volt (dc) car air compressor (125 psi) and i am going to incorporate this somewhere in the cannon, the air compressor is really small so i could make it built in. i really want to make this cannon portable but i am concerned about the weight of it with the fire extinguisher tank, Any Ideas?

Topic by struckbyanarrow 9 years ago  |  last reply 8 years ago


TRigger ideas for a ball valve air cannon

Hey is any one searching for a trigger mechanism for there ball valve operated air cannon well here it is a http://rokclan.com.net.sc then go to my inventions then advanced high powered rifle

Topic by ghostman!! 11 years ago  |  last reply 8 years ago


Piece List - Big Air Ball Tower? Answered

As above

Question by TwistedParadox 9 years ago  |  last reply 9 years ago


Making an air well

I was thinking about another fun project that draws water out of the air with just the sun's energy. I noticed the empty open vinegar bottle I washed and set to dry on my window sill accumulate more moisture every day. It was pooling water in the bottom after a week. The bottle shape is like a ball with a long spout. I read a little about air wells on the web, but they are very large structures. It would be fun to build a small one that would make a few glasses of water a day. Comments?Here's one link Air Wells & Dew Ponds

Topic by robbtoberfest 12 years ago  |  last reply 4 years ago


one way air valves (like on a football,basketball etc)

Looking for valves see photo (ok don't uploader not working) Well a valve that you stick an inflator needle into like on a soccer ball, basket ball etc. Need 12-50 or so. Anyone have a source? I've searched but no luck, it might be I just haven't phrased it right but... TIA Danneauxs

Topic by danneauxs 6 years ago  |  last reply 3 years ago


is there any knex instructables that are ball machines, that use the lift of the big air ball machine?

I bought the big air ball machine, and was wondering if there are any instructables that use the lift from it.

Question by the poodleo 8 years ago  |  last reply 8 years ago


Knex ball machine.

I was wondering if somebody could make a new knex ball machine, with 4 paths, and with 3000 - 5000 pieces. what you can use: any connectors or rods anything from the big ball air tower set any gears any motor what you cant use: orange tubing over 10ft of chains (unless its some kind of other lift) these are other ball machines i made. i broke them because there were not many paths, the ball kept falling off, or that they just werent good enough. project box project immeuble project nano project dos project aggresor (the famous knex big ball factory below)

Topic by ~KGB~ 9 years ago  |  last reply 9 years ago


Why is the ball valve of my potato gun releasing the pressure? Answered

The ball valve of my air cannon releases the pressure once it climbs above 5 psi. Is there any way to fix this? Or am I stuck with a $30 door stop I'd buy a new one but it just started to leak air, it was working, plus it's glued to my U joint, and really don't wanna rebuild it.

Question by monkhm 7 years ago  |  last reply 7 years ago


New KNEX ball Element

I have found out this new element that works at high speeds better. When it turns I recommend you keep a guardrail below. This is better when this is high up in the air because it will get more speed.

Topic by rexdino5 10 years ago  |  last reply 10 years ago


How fast can you spin your Golf Ball?

I played around with some balls placed into the airstream of a little blower. Everything light enough just "danced" in the air like being hold on invisible strings. But not so much the golf ball! You would expect those dimples are good for reducing air friction but do they also offer stability in some cases by making the ball spin? Check this video I recorded while playing - to me it looks like with a proper nozzle there is even more speed possible. https://www.youtube.com/watch?v=014QkXuTL0o How fast can you make it spin?

Topic by Downunder35m 2 years ago  |  last reply 2 years ago


Problem with compressed air, ping pong turret

Hello all, I am in the process of making a ping pong ball turret powered by an air compressor, I’m using a solenoid valve to trigger the air electronically.i have had some exact diameter steel pipe milled out which is 250mm, so the diameter of the balls are 40mm and the diameter of the pipe is roughly 40.5-41mm. And I’ve sealed off one end with a tapped out hole for a nozzle fitting. My compressor goes up to 7 bar -around 100,psi -. Do finally to the topic 0f my question, i have tested the firing of the balls by firing 7 bar through an compressor gun, and to my surprise it didn’t fire across the garage like I expected, instead it made a very high pitched noise and the ball vibrated inside the tube, eventually the ball would rise up the tube and eventually speed up towards the end of the tube but still only launched at most 1 meter. Any help on how to fix this problem would be excellent. As I expect 100psi through an exact diameter tube would fire the ping pong ball very far. Feel free to ask any questions if I haven’t been detailed enough. Cheers

Question by bashmore00 3 months ago


what are the specs to making a fog ball cannon from a rubbish bin, fog machine rubber band and garbage bag? Answered

hey, a while ago in high school out teacher was showing uss tuff to do with the transferance of energy and stuff like that, what he brought into class one day was a rubbish bin, with a hole cut out bottom, and on the lid, there was a rubbish bag(the big black ones) , on top with a rubber band taped to it. basicaly the way it worked was, the band is taped to the bag,m when you pull the band back, you pull back the bag also, which pucks in air into the hole in the bottom of the bin,but at this time the hole is actually the top of the cannon, as thats where the air enters and comes out. now when the air is being sucked into the bin, our teacher also had a hose from a fog machine attached to it, which made the bin suck up air, now when he let the band go when the bin was full of air, a ball of air shot out, and the fog remained inside that air ball so we could see where the ball went, which was around 20 meters, anyway, the fog ball could nock over polystyrene cups from 20 meters. i want to know exactly how to build one of these as i cant really remember how they look like as i have forgotton, i was reminded of these once when i saw one being used on rollercaoster, in the minishow, elliot and the surfing scientist.

Question by oldmanbeefjerky 8 years ago  |  last reply 8 years ago


Pneumatic soda can cannon on Mythbusters?

I just watched a Mythbusters where they made a pneumatic soda can gun.  Go to 5:50 in this video to see their description of it.  Go to 7:00 to see it in action.   http://www.youtube.com/watch?v=ZMYuQ5daXxk&feature;=related My questions are: what is the "fast acting valve" he used?   How do you refill that thing? Anyone seen an instructable for something similar?  I've seen lots of PVC versions, but I like the metal version because it's sexier looking, and potentially higher pressure/power. Thanks!

Topic by guaps 8 years ago


Fozzy13's AiR Experience!

Being an Artist in Residence at Instructables was an amazing experience.  It's difficult to put into words but I'll give it my best shot. Let's start at the beginning!  Because where else would you start?  I'm a college student, but I wasn't when I started to love building things.  A knee injury years ago took me out of wrestling for a summer and I used my ample free time during that time period quickly filled up as I was excited by the idea of breaking water into hydrogen and oxygen.  Over the past five years, I've grown to love making all sorts of things.  Instructables has always been a fantastic community to get ideas for projects and share what I've made.  After being part of the community for so long I wanted a chance to be a bigger part of Instructables and have the opportunity to meet some of the people who I've been following on this website for years!  Hopefully that only sounds mildly creepy.  The Artist in Residence program allowed me to have just that opportunity. I had the honor of being one of the very first Artists to make use of Instructables/Autodesk's brand new facility.  It's incredible.  If you're on a tour, it will be referred to as the greatest workshop and creative space in the world, and after working in it for a month,  that's an easy statement for me to believe.  The metal shop is where I loved spending most of my time as I worked on my main project: a jet engine.  However, I barely scratched the surface of what's possible even when I dabbled in playing around with 3D printing and laser cutting.  I'll post links to the projects I did when I'm done at the bottom of this post! I could go on and on about how exciting it was to learn how to TIG weld, or pull my first 3D printed object out of the printer for cleaning.  That's not what I loved most about being an Artist in Residence.  Don't get me wrong, that's why I was there, and I loved every minute of it!  But what I loved most was just being in the office at Instructables.  It was an amazing feeling to get to interact with lots of different people who all in some way loved to make things.  Being around people who know what Maker Faire is meant a lot to me!  Usually mentioning it only yields confused faces in my city.  It was great getting to talk about different projects people had done or were working on, which made me love "Build Day"s more than anything.  Being at the headquarters of Maker Culture made me feel at home. I've been away from the Pier where Instructables HQ is for a few weeks now.  I miss everyone I got to meet there, and I miss having the resources to make anything I could imagine.  Being and Artist in Residence will always be one of my best memories ever, and I can only hope that at some point I'll end up back at Instructables to see the awesome people I met and build some more cool stuff. Thank you to everyone at Instructables who made my short stay a great experience!  I can't thank you enough. - Projects! https://www.instructables.com/id/How-to-Make-a-Mini-Compressed-Air-Turbine/ https://www.instructables.com/id/3D-Printed-Modular-Ball-and-Socket-Joints/ https://www.instructables.com/id/Make-your-own-Instructables-Robot-Keychain Jet Engine Instructable coming later!

Topic by fozzy13 5 years ago  |  last reply 5 years ago


Uses for Old Basketballs & Soccer balls

I have access to loads of old basketballs and soccer balls that are always floating in the river by my house. (they get washed into the river from people's yards whenever it storms) They're usually fairly worn and dry-rotted from sitting in the sun but most of them still hold air. I was trying to think of some type of outdoors, maybe flowerbed/garden related, craft I could use them for. I'm looking for practical uses or even artistic uses. I've thought about cutting them in half and making hanging planters, but we don't really have any places to put hanging planters in my yard. If you have any ideas or inspiration, please do share. Thanks!

Topic by geekchic 9 years ago  |  last reply 9 years ago


for sale: illustrator sgi paintball gun/marker(just gun)

In perfect condition and  it uses co2, blue, has a fore grip air reduser for better shooting if anybody is interested please leave a comment, selling for around $100 although we can maybe talk the price down a little bit.as of 6/13/10(this is not my gun in the pic but looks exactly like it.

Topic by shdsteel 8 years ago  |  last reply 8 years ago


Nerf Gun Valve? (Air, Need a valve)

Yea. Basically, I'm trying to make a nerf rifle with a better trigger. I've used ball valves in the past, but those let out the air way too slow, and you jerk when you pull that.  So I need some kind of valve that can be pulled, and is airtight. Also, I'm not so good at this whole construction thing, so the easier, and the cheaper the better. Home Depot is probably where I'll be picking up the materials from... so yeah.

Topic by Batryn 8 years ago  |  last reply 8 years ago


pumatic airsoft gun help ? Answered

Ok so heres my situation. About 6 months ago I made my own pneumatic airlift sniper but even though I could get about 80 lbs of pressure stored up before I pulled my trigger my sniper only shot as far as my 300 fps gun. My question is why cuz I had a lot more force in my pneumatic sniper then my other gun and it doesn't seem to matter. My sniper was made of a metal nipple about 9 inches long and 2 inches in diameter. I then put a cap on one end and a reducing coupler on the other. I drilled a hole in the cap and inserted a valve that allowed me to attach the chamber to a bike pump. On the end with the reducer I then added a ball valve that worked as my trigger. After the ball valve was another reducing coupler that brought the size down from an inch to 1/2 an inch. Into this coupler I screwed a break line about 50 cm long(sorry about the unit change I don't remeber its length in inches) and it fit the bb very nicely. I also added a little contraption I made from paper clips that allowed the gun to be tired downward without the bb falling out. However I don't believe this was the problem as I fired the gun when their was just a wire across the back of my breakline ,to keep the bb from falling into the gun ,and the distance seemed the same. I made sure every connection before the ball valve was sealed well except that the gun did leak at a rate of 20 lbs for minute because of a bad connection with the valve that connected with the bike pump. If you need more info just say so in the comments but I don't have the gun with me right now so all i have to go off of is my memory. Thanks for your help I really appreciate it. : )

Question by inconceivable1 2 years ago  |  last reply 2 years ago


What is a valve that can be opened and closed quickly and easily?

I want to make my own water gun (a la supersoaker), the only pitfall I have is I can't find an appropriate valve. A sprinkler valve requires electricity, a modded one will only close when all pressure is released, a ball valve would move to slowly, or be to stiff for a simple trigger mechanism... and I did have another example, but can't remember it. Essentially I want a valve with a semi-automatic action that can release large volumes of propellant. Thanks in advance.

Question by AdmiralNiik 8 years ago  |  last reply 8 years ago


Pneumatic Toilet Paper/Spud Air Cannon-

This is a project I'm wiling on with my little brother. I'm building a cannon out of PVC. I want it to be able to shoot four times without adding air again. So my idea was to make four chambers to store the air. Each chamber would have an individual ball valve. Then another ball valve where the chambers stem into the main body and barrel of the cannon. From the three inch PVC Im going to drop back down to 2"-2.5"  PVC for a more forced compression, then the barrel will be 4". I understand that PSI is a pressure measurement, however I'd assume that my PSI's wouldn't be able to exceed the lowest grade of PVC I build with? That would only make since.  The problem I'm having is, I'm not sure if any stores such as home depot or lowes has couplets that could couple 4" and 3" as well as 3" to 2". I also need to know what kind of pressure would I need to get to launch toilet paper into about a 10-15 foot height? Or would this just be a trial and error experiment?  Thanks for all help. It's much appreciated!

Topic by B52280 7 years ago


How to make a balanced spool valve? For a PVC airgun, need quick release valves.

I'm trying to make a 50 caliber airgun, but this time with a better valve. My previous one had a ball valve, and it's sticky, hard to aim, and just troublesome. I did a bit of research on airgun valves, and it seems as though the balanced spool valve is a good one to try. However, all the searches seem to be focused on the discussion, not the making of the valve. I'm going to be using PVC, hopefully 3/4"+ for the air chamber. Anyone know how, or know a better valve? Thanks! 

Question by Batryn 7 years ago  |  last reply 6 years ago


Small Electronic Valve?

So I was wondering if there was anyway I could make or buy an electronic air valve. What I need is something simmilar to a sprinkler valve only smaller and with smaller holes on each side so I could attach a relatively small air hose to it (~1/4" outer diameter). I plan on using this to replace the ball valve on my homemade nerf gun. Any help is appreciated :)

Question by Electroinnovation 7 years ago  |  last reply 7 years ago


Finding the altitude of a ball using weight and time airborne

I was shooting my tennis ball cannon today, and i was wondering if there was a way to find out the altitude of the ball using the time it was airborne and the weight of the ball. I have no idea how to approach this, i dont know of any math formulas that we've learned so far that can compute this. I think it would have to factor in drag, gravity, the weight of the ball, and how long it was in the air. I just dont know how to do it. If anyone with a better understanding of physics and mathematics can help me out, or point me in the right direction, it would really help me out! thanks!

Topic by John Smith 9 years ago


How to determine the psi in a tank when it joins with a larger tank that's empty?

Ok, so I'm going to try to make this. However I want to make it so I can detach the big pvc reservoir and put on a new one for more than one shot. However, this is probably going to lower the psi when the air moves into the smaller reservoir.  One more question: my plan is to make the air tank just screw onto the gun. Will this still be airtight? Do I need a quick release valve instead of threaded pvc? My plan is to make the larger reservoir but put a ball valve on the end where it connects to the rest of the gun. This is so I can screw it on and turn the valve.

Question by General Eggs 7 years ago


Pressure Washer? Answered

I would assume it can't be, but it would be really lucky if a pressure washer could fill an air tank to the pressure the washer is rated for.  So can a pressure washer that says 5000 psi really fill a tank to 5000 psi with the right fittings.  It probably won't be breathable or paint ball worthy but is it plausible.

Question by jj.inc 8 years ago  |  last reply 8 years ago


Safe, efficient, breech-loading pneumatic tennis ball launcher?

I was interested in building a tennis ball cannon, and have seen breech-loading ones in videos.  Does anyone know of free plans for one?  I was also wondering if there is a disadvantage to ABS other than the slight cost difference.  I'm looking for safety and an efficent barrel-to-tank ratio.  How would one make a resettable pressure release in the case of some sort of accidental over pressure?

Question by nlaluzerne 6 years ago


How to positively charge something? Answered

I was sitting here in the middle of a thunder storm and I had a thought, usually the clouds are negatively charged during a lightning strike, so, if you used a large cannon to blast a positive iron ball into the air, you may be able to get lightning to strike it, then collect it to see what the lightning did. So, you would you charge a cannon ball? 

Question by jj.inc 6 years ago  |  last reply 6 years ago


Rocket Launcher

I need ideas for the firing system for a rocket launcher. I have some pictures of what i have built. But i do not have a firing system for it yet. Any ideas would be appreciated. This is a knex rocket launcher that used the Air Ball Tower tubes.

Topic by TeacherOfTheWays 12 years ago  |  last reply 11 years ago


solar powered cooler

Using these ideas as a starting point:http://en.wikipedia.org/wiki/Icy_Ballhttp://en.wikipedia.org/wiki/Einstein_refrigeratorhttp://en.wikipedia.org/wiki/Gas-absorption_refrigerator"Another variant uses air, water, and a salt solution. Warm air is passed through a sprayed solution of salt water. The spray absorbs humidity from the air. The air is then passed through an evaporative cooler. Humidity is removed from the cooled air with another spray of salt solution. The salt solution is regenerated by heating it under low pressure, causing water to evaporate. The water evaporated from the salt solution is recondensed, and rerouted back to the evaporative cooler."Directions on how to make an icy ball. URL works occasionally.http://crosleyautoclub.com/IcyBall/HomeBuilt/HallPlans/IB_Directions.htmlhttp://blog.modernmechanix.com/2007/07/19/refrigerator-uses-solar-energy/Is a non-flammable, non-toxic, and low pressure version possible?

Topic by beforethought 10 years ago  |  last reply 2 years ago


how many psi can a 5 gallon plastic bucket (found in home depot) can take?

So im doing this for a chemistry project. My plan: to create a cannon with buckets and tubes with ping pong ball. I use dry ice and water to compress gas in the bucket and release the air through the valve. i realized that when i puff air into it and conceal it, (3 to 4 times) the bucket starts to deform.

Question by punch2dface 4 years ago  |  last reply 4 years ago


How To Inflate Plastic Bottles- into balloons- With Heat and Air Pressure?

1).  I would like to use PET drinking water bottles  and polyethylene plastic bottles ( taco Sauce, mustard, plastic juice bottles)- for insulation in an  attic? Choice 1). using a heat source like a heat gun and my air compressor can I inflate old PET plastic water bottles - into balloons to act as insulation spheres ?   Each week  I would spend time turning the plastic bottles into thin-walled spheres that would fill up the attic with light-weight spheres- maybe the size of a soccer ball?  . 2). If Not  choice 1). lets learn how to process plastic bags and packaging into a shredded stringy material to do the attic insulation job. The source of bottles is endless and I hate recycling these to the city and then purchasing expensive fiberglass batt insulation at $40 per roll.  Any DIY wizards try this stuff?  I could literally mega-insulate the attic. If treating the material with Sodium tetra-borate  borax -to get a fire resistance that is doable too. They make clothes, blankets, molded items and padding routinely from old bottles: Why can't I? I would build a shredder or modify a branch shredder machine to do this and make it my recycling hobby over the long term.

Question by KM6 3 years ago  |  last reply 3 years ago


Winter weapons of snowy destruction

It's winter and snow is everywhere (well where I live there is) People are sledding and making snow angels. And of course my favorite part- Snowball fights. Snow in ball form whizzing thru the air towards people. Me loving to build stuff and loving to improve it to, I wanted to make something that could throw snowballs better than any person. I have an idea for a couple launchers and cannons but I want to see other people's ideas. So post anything, a launcher, a cannon, a catapult, a chucker. Anything that can accompany someone in a snowball fight. So people POST.

Topic by ostomesto 8 years ago  |  last reply 8 years ago


Converting gravitational potential energy into air pressure to launch a projectile?

Hello my name is Aaron! I am a high school senior from northeastern Kentucky designing a pneumatic system of sorts for a science competition and need some help. I will be building a device that converts gravitational potential energy, from a falling mass, into air pressure (or possibly the movement of air depending on the design) to launch a projectile a specific distance (max distance needed is 8.25 m). What I am thinking about doing is using one double action pneumatic cylinder (DAPC) as a bellow in which a falling mass (max 3.500 kg at a max 90 cm) would strike its piston shaft, creating positive pressure within the system. With that positive pressure another DAPC’s piston would simultaneously strike our projectile sending it airborne in theory. Below there is an illustration of my idea, sorry about the poor quality. So what I need help determining is would this design work before I start buying parts? If so what approximate sizes should the two cylinders be and should they be different sizes to maximize the force exerted on the projectile? If you have any other ideas concerning the design or any questions about the project PLEASE feel free to share!!! Below are some of the design rules that pertain to this project along with some notes in italics about them. Thank you very much for your time in advance! ------------------------------------------------------------------------------------------------------------ Description:    -Prior to competition, teams will design, construct, and calibrate a single device capable of launching projectiles into a target and collect data regarding device parameters and performance. Design Constraints:    -The launching force must be entirely supplied by the gravitational potential energy from a falling mass less than or equal to 3.500 kg. Any device part whose potential energy decreases and provides launch energy is considered part of the mass. The mass may consist of multiple discrete parts, which together count as the total mass.    -During each launch, the gravitational potential energy must be converted to air pressure or air movement, which is then used to launch the projectile, either directly (e.g., pop gun style, etc.) or indirectly (e.g., using a pneumatic cylinder to swing an arm, etc.) All device air chambers must start at ambient air pressure and must automatically return to ambient air pressure.    -The launching device (would look similar to this with the adjustable angle to accommodate different ranges), including the projectile and all components, must fit within a 75.0 cm x 75.0 cm x 1.00 m box in ready-to-launch configuration, in any orientation chosen by the team. Weights used to stabilize the device must be within the box.    -The triggering device (would look something like this except elevated with a mass suspended ready to be released) in not considered part of the device and must not contribute energy to the launch. It must extend out of the launch area, allow for the competitors to remain at least 1.00 m away from the launch area, and does not need to return to the launch area after launch. The triggering device must not pose a danger to anyone due to flying parts or excessive movement outside the launch area.    -Teams must provide unmodified tennis, racquet, ping pong, and/or plastic practice golf balls to be used as projectiles. Teams may change projectiles for each launch.    -The launching device must be designed and operated in such a way to not damage or alter the floor.    -Electrical components are not allowed as part of the device or triggering device. The Competition:    -Two targets, designated by small marks on tape on the floor or panels lying on the floor, must be placed in front of and centered on an imaginary line parallel to the launch direction that bisects the launch are. Supervisors are encouraged to place sand, cat litter, or similar substance in the area around the targets to help indicate landing spots.    -The targets must be placed in front of the launch area at distances between 2.00 m and 8.00 m (in intervals of 10 cm). A distance of at least 2.00 m must separate the targets. Target distances must not be announced until after impound is over and must be the same for all teams. Room ceiling height should be considered when setting the distances.

Question by ahoback 4 years ago  |  last reply 4 years ago


Mortars ideas

Heres a spot we can put up ideas about mortars. look for "tennis ball mortar" for the base idea and then you can modify off of it. i been thinkin mabey mortar that can shoot like a shotgun, (air soft pellets or bbs) or a huge cannon that can shoot footballs lol. ill think on it and post somthing. good luck with ur ideas and have some fun. ...mabey pvc pipe for the barrel or somthing...

Topic by XI3 11 years ago  |  last reply 11 years ago


knex sniper

Um i have the knex big air ball tower and the thriller or something like that rollercoaster. im gonna make a gun cause i already have one pistol but i wanna know what gun can i make using those parts and how powerful. id like it to be a sniper but most of the snipers i dont think i have pieces for. dont worry about difficulty i can build anything (not to brag)

Question by blaster876 10 years ago  |  last reply 6 years ago


homeade paintball gun

Hey everybody please give me tips or designs to help me make the homeade paintball gun using PVC or other inexpensive peices!!PPPPPLLLLLLLLLLLLEEEEEEEEEEEEEAAAAAAAAAAAASSSSSSSSSSSSSEEEEEEEEEEEEEHHHHHEEEEEEEEEEEEEEEEELLLLLLLLLLLLLLLLLLPPPPPPPPPPPPP!!!!!!!!!!!'how do you like my muzzleloader paint ball berret max range 400 yd easly. the whit one is a 5 shot paintball shotgun or rilfe ( you fill it up with air then close extra valves (5 shot muzzleloader) ) .

Topic by receiver545 11 years ago  |  last reply 8 years ago


Bubble Machine, Sleek iPad Stand, Laser Cut Wedding Dress

Bubble Machine Two-Ingredient Ice Cream Laser Cut Wedding Dress Secret Minesweeper Pillows Simple Workbench Sleek iPad Stand Special Effects Makeup USB Game Pad Alcohol Stoves DIY Boom Box Desktop Skee Ball Make Viking Era Paint Altoids Stereo Mixer RFID Car Immobiliser Solar Hot Air Collector

Topic by randofo 8 years ago


I am new to paintball and I can rent any paintball gun for free on my birthday. Which one should I get? Answered

 I have never played paintball and I love to snipe in video games :) but IDK if I have good accuracy in real life.  This would conserve bullets.  I also have a choice of a full-auto.  This would waste bullets and I hate "Spraying and Praying", but accuracy wouldn't matter.  I am confused!

Question by garrett10 9 years ago  |  last reply 8 years ago


Knex gun

Um i have the knex big air ball tower and the thriller or something like that rollercoaster. Also some parts left over from the starburst spinner set. im gonna make a gun cause i already have one pistol but i wanna know what gun can i make using those parts and how powerful. id like it to be a sniper but most of the snipers i dont think i have pieces for. dont worry about difficulty i can build anything (not to brag)

Question by blaster876 10 years ago  |  last reply 8 years ago


High Presure Test for glass, looking for some help

I am new to this web site and I do like what I have read so far. I am an test engineer and I am trying to come up with a way to get 15 psi in a glass bottle with it being 98% full with water. also this is to test the cap so the cap wust not be tampered with. the way I am doing it now is to drill a 1/2" hole into the body of the glass bottle and use a rubber stopper with an air line in the center of it and apply the correct amount of presure. but when I drill the half inch whole in the glass, the glass will brak about half the time or will crack and split under presure. I thought of drilling a smaller hole and using a air needle like one would use for soccer balls or basket ballls. Does any one have any suggestions. Test professor

Topic by test professor 11 years ago  |  last reply 11 years ago


Bike pump problem?

I was using my bike pump today to fill a pneumatic launcher, and finally I just got fed up with the leaking around the pump base. On every stroke, the first 3/4 of air would be leaked out of the base, and it would only compress the remaining 1/4 of air remaining, and that would only compress if you pushed down very hard, and quickly, otherwise it all leaked out. And no matter what pressure the launcher was pressureized to, the pump handle/piston would slide down slowly, getting pushed down under it's own weight, meaning that there was almost no resistance to it. I think the leak is occuring where the tube meets the pump base, and you can feel air rush out with your legs as you pump. I'm pretty sure there is a one way valve in the gauge portion of the pump, which connects to the base with a hose,  and the filling hose is coming out of it, which is allowing me to compress at least a little air before the rest leaks out. I disassembled  the pump, starting with the base. Turns out, the leak was from an oring on the tube which was not tightened down enough by a screw on ring around the base of the tube. Put it back together, and voila, pushing my finger against the schrader valve connector and pushing down on the pump handle created pressure against my finger and no leaking. As soon as I hooked it up to my launcher, i realized something was up, I could pump down once, but the pump handle just got pushed upwards as soon as i let go. This is what I can't figure out how to fix. It seems the one way valve in the gauge portion is locked in the open position. Anybody know how to fix this? EDIT: Okay I took pictures of the pieces. I now cannot figure out if the valve is in the base, or the gauge portion, so i have included pics of both. Hopefully someone can help me figure this out. EDIT 2: Turns out the valve is in the base, and the ball just fell out when i first disassembled it, i have now found the ball and it is working fine.

Question by LiquidLightning 7 years ago  |  last reply 7 years ago


A good deep vacuum pump? Answered

I'm looking for a vacuum pump for use with projects like the fusor included in make magazine, a laser tube, or a plasma ball.  It doesn't need to move huge amounts of air, but nothing below 1.5 lpm.  It also needs to have an ultimate vacuum of at most 25 microns.  I have been unable to locate any pumps which meet these standards, all of them have ultimate vacuums of around 100 to 75 microns or are completely unlisted.  Do any of you have some experience with these and some advice.  I don't need something for pumping out heating/cooling units daily, just a very deep vacuum a couple times a month.

Question by jj.inc 5 years ago  |  last reply 8 months ago


Possible improved t-shirt cannon design. Will it work? Answered

I had an idea for a t-shirt cannon design using combustion instead of compressed air but desided against it when i found that it would most likely burn the shirt. I have since then changed the designs to one where I think I solved the problem but I would like some feedback before I start buying materials. The basic change in design is that is uses this piece: http://www.homedepot.com/h_d1/N-5yc1v/R-100348177/h_d2/ProductDisplay?langId=-1&storeId;=10051&catalogId;=10053 [Starting at the top valve and going clockwise, name the openings 1, 2, and 3.] The blast would be through 2. The shirt would come out 1. That way (hopefully), the majority of the heat would go through a shortish piece connected to 3 while the compressed air goes everywhere including out 1 launching the shirt. Another heat helping idea was using a sort of heat sink by putting a piece of free floating (unattached to walls of pipe) metal pipe inside the PVC to absorb some of the heat. Don't know how effective that would be, though. Finally there's always using a fire retardant material as a buffer between the shirt and the gas attached to a tether so it won't fly away. Speaking of which, is the reason the shirt gets burned because of actual fire or just getting so hot it spontaneously combusts? Also some general improvements assuming the previous ones work: 1) To avoid the problems of using a Taser (like cost and safety), I was going to use kipkay's idea from another video of using the igniter from a BBQ lighter 2) To limit power (assuming a short burst of fuel was still too much), I was going to put a ball valve on 3 that I could open a bit to let some air pass out that way 3) For all spud guns in general, Instead of having a screw on piece to let fuel in which takes more time to use, I thought of using another ball valve to just open and spray the fuel in. Please give me any feedback, comments, or questions you have, including those of the "You're incredibly stupid. This will not work at all/kill everyone" variety. Be nice. I realize I asked a lot of questions. I'm excited.

Question by cowmanpoke 7 years ago  |  last reply 7 years ago


I have a Toyota conquest 1.6, 16 valve, 2002 model. My car is loosing compression. Please help?

I have a Toyota conquest 1.6, 16 valve, 2002 model. I have changed the fuel filter, changed the oil, bougi cords, ball joints, brake pads and the spark plugs. Last year October i put in a new clutch plate, pressure plate and trust bearings plus a new head gasket. The fuel filter and air filter is clean. My car is losing compression. One mechanic says my clutch plate is gone, one mechanic says the flywheel has either shifted or needs to be skimmed and the other mechanic says its my rings and bearings. What is the problem and how can it be fixed?

Question by ArupaA 2 years ago  |  last reply 2 years ago


Making it more powerful?

Hi,  I have brought a sphero 2.0 which for those who don't know it a robotic ball about the size of a baseball. I decided to try and make a car for it out of knex although I will only be able to make it go backwards and forwards. I built a frame thing with a small wheel in the middle of it and sphero sits on top. The axle that the wheel is on has a gear which then connects to the drive wheel axles on the back using another gear. This works fine when in the air but when on the ground it's too heavy for sphero to power it. I've tried putting bigger gears on the front and vice versa, i've also tried using a pulley but it just isn't budging at all.  Say if I was using the standard knex motors how would I go about making it produce more power? 

Topic by mikesaa309 5 years ago  |  last reply 5 years ago