false piston: how the hell do I make that?

Hello Instructonauts, I have a bit of a problem. I need to make an object with a piston like action. This wouldn't be such a big deal if I could actually just use a piston but I can't. I need a method for creating a piston movement of a cylinder inside a tube so the device moving the piston cannot be any wider than the piston. I considered pneumatics but that would require supplies I do not have and have never worked with. Does anyone know a way to make this object?

Posted by finfan7 9 years ago


Need piston valved gun experts

I just built a big piston valved spud gun. I can't get it to fire. When I release the pilot valve no air even comes out. The piston is sealing though. I think it might be theres not enough air in it. I charge it using a 1.5 gallon compressor at 100 psi. The chamber is 5 foot of 3 inch tubing. I don't know why no air even comes out of the pilot valve. I know their isn't leaks or none big enough to hear.

Posted by thejrb 10 years ago


what would be a good material to use for the piston

What would be a good material to use for a piston other than pvc rod that's too expensive. I was thinking along the lines of cast epoxy or shapelock. I need a material that's pretty cheap too.

Posted by bob the builder #1 9 years ago


Homebrew hydraulics?

I've been working on a project that, if I manage to build it as designed, would require four actuators or some kind no more than 1" in diameter. Hydraulics seem to be a good fit for this application (I wouldn't need more than 30 PSI, single acting only) since compressed air would be too "spongy." The actuators also need a total travel of about 24." That's where I run into trouble: I can't find hydraulic cylinders that meet the bore and stroke requirements. I have an idea to build my own which I'd like some feedback on before I dive in, or perhaps someone has an alternate suggestion. I have some thin walled, 1" chromed shower rod that makes a perfect outer cylinder (and the chrome finish would look snazzy!). Add in some 1/2" PVC pipe for the inside and I think I'm pretty close. First attempt was to make molded silicone pistons on the PVC. I got some pretty good results but it's not entirely leak-proof, so I lose pressure. My next idea is to use a rolling-sock seal made of 1" lay-flat PVC discharge hose. Bind the hose to the PVC pipe with a good seal, double it up over the pipe and seal the other end before stuffing it into the metal tube. Anyone think this is a lost cause, or have another suggestion?

Posted by Smidge204 9 years ago


Solar steam piston?

Right. Still hung up on this whole solar energy thing I've been looking into steam but it all seems: complicated, dangerous, expensive, and all kinds of freakin hassle. I think this is largely because people working in this field now are just trying to plug solar energy into where the fire would normally go, but in many ways light is a lot more versatile, and this might take a complete rethink. So, after twenty minutes of ill-informed and distracted thought, how about this: Two or more pistons, each with a little bit of water or other fluid. Base is thick glass, both attached to a shaft or gear to generate rotation. Concentrated light (like 6 kW worth, or whatever) is shone in through the base of one piston. The fluid vaporises and the piston expands. When it's fully extended the light beam flips over to the other piston. That one starts expanding while the first one starts contracting. you might have some sort of heat sink which is oly applied during the contraction bit. This would be fairly low speed, but should generate a fair bit of torque and would be really really simple. Someone just stole my patent, didn't they?

Posted by SolarFlower_org 9 years ago


Piston Travel Distance

I'm currently working on a coaxial spud gun with a 1.5 in. chamber and a 1/2 in. barrel. I need to know how much space behind the piston to leave. I was recently informed that the distance should be 1/4-3/8 in. Please tell me if you know anything

Posted by bob the builder #1 9 years ago


Steam engine model made entirely with glass!

Here is a beautiful model of a steam engine made with glass.

Posted by blkhawk 4 years ago


Single Piston Air engine

Hi all, need help/ advice in designing a single piston air engine, It is part of a mechanical engineering course I am currently studying, the only parameters i was given are - Single cylinder with vertically displaced piston with rotation of the input shaft on a horizontal axis - free standing with an operating envelope of 300mm x 300mm x 300mm - accommodate a nominal piston diameter of 20mm - engine capacity of 6.0cc / 6000mm (cubed) Any help would be greatly appreciated Thanks in advance

Posted by DavidO242 8 months ago


Homemade airsoft sniper (need help on Piston)

Hey all :) , first of all , i dono if this is the right place to post this but , meh , tell me if its the wrong section... Guys , i need help on making a Piston with its cylinder . i have no idea what parts i should use , i thought of cans but most of them has a bend at the end... if u dont know what a piston is  , then here you go... and dont tell me to buy an airsoft sniper , they dont sell any here in bahrain -.-...

Posted by ray090 8 years ago


New Vacuum Pump Idea

I have a new idea about a new type of positive displacement vacuum pump.  Its of the piston variety, but instead of a one way valve which doesn't work when the pressure gets low enough, another piston is used to act as a valve switching between the vessel to be evacuated (when the main piston is pulling a vaccum) and the atmosphere (when the piston pushes the air evacuated out). This solves the one way valve problem.  Could this pull a much lower vacuum?  I need a fairly strong vacuum, but I don't want to have to build/buy a turbomolecular pump. Also, i have a metal lathe, that's why i'm going with the piston variety.

Posted by guyfrom7up 8 years ago


Piston jump boots

I dunno if you have ever seen this guys 'rocket boots' (not really rocket powered) but they are sort of neat. They do not get the same results as simple mechanical leaf spring sort of moon boots I see, but the concept is pretty interesting for those of us who are fans of combustibles.  this is a video http://www.youtube.com/watch?v=w7s-tnzPZ3c article http://www.technovelgy.com/ct/Science-Fiction-News-Comments.asp?NewsNum=740 Now my question: How would you improve this sort of unimpressive piston powered boot? I was thinking if one could double or even triple the chamber size of that piston, or use multiples of them, maybe use a more potent combustible than gasoline.

Posted by ThorsMitersaw 7 years ago


Do we need another cannon

So After toying with the Idea of making a large and powerful cannon without making a piston valve I do believe I have an answer to the problems associated with using ball valve (bad for power) and piston ported valves (too much effort) I think I've found a simple way of making this work, only question is, with gas power and pneumatics galore do we need another? It would be in the same sort of category as the behemoth but a simpler build, what does everyone think?

Posted by killerjackalope 10 years ago


Engine Cumbustion & Etc.

I've been knocking around an idea in my head and I was wondering if anyone had an answer to a few problems associated with said idea. One of the problems/road-blocks is how do modern cars run? More specifically, is the gasoline that goes into the pistons for combustion an actual air/gas mixture, or is it air/liquid-gasoline? And is there a way to manually adjust the ratio of air-to-combustible? The reason I ask is because I was hypothesizing whether or not it would be feasible to replace gasoline with a more efficient combustible, and this combustible would greatly depend on what is actually put into a modern petroleum-based car engine's pistons. Thanks for any info!

Posted by kenizl86 3 years ago


Manual air compressor

I had this idea just drop on me a few minutes ago and I was wondering if anyone could give me some feedback on if something like this would be feasible or not. Also if anyone thinks it's a good idea just go ahead and build it because I dont have the tools or space for something like this in any case. The idea is to have some sort of tank with a large internal volume, cut it of at the top and arrange a sort of secured piston with a heavy weight on top, attach it all to a frame so that the piston stays level and secure. The piston with the weight on can then be connected to a multi-stage pulley system to allow one to lift the  heavy weigth, sure it would take a long time but for a manual air compressor it should be feasible Then at the bottom of the tank one would have a high pressure release valve with some sort of standard connector for transfering the compressed air to a sort of pressure tank for use. I never saw anything like this before, although I'm sure someone must have done it at one point or another. So what do you all think? Any input?

Posted by wolty 7 years ago


weedeater repair and stuff

how would you fix a weedeater where it wont suck any gas in it has lost compression and you can actually hear grinding in the cylinder when the piston moves up and down and a screw stripped on the crankcase? and you cant get off the exhaust because it was like welded on.

Posted by BIGHAIRYDUDE 7 years ago


Extending Office Chair?

I want to raise the height of my office chair, about 4" or so, but I don't know how to do it. The piston is already maxed and its still too short. Does anyone have any ideas on how I could accomplish this?

Posted by Tsylord 8 years ago


Tesla turbines as viable generators?

Anyone have any thoughts about Tesla turbines, potentially as something steam based to plug into an alternator? The internet seems to be of the opinion that they're either fantastic or crap. I'm thinking of this as an easier and cheaper option than a steam piston or Stirling system for my solar energy thing.

Posted by SolarFlower_org 9 years ago


Instructable won't appear in search engine?

I posted my instructable last night, and it shows up under the posts for my user name, but it isn't in the Launch It! group display (or any group for that matter) and doesn't show up under keyword searches. Is there some kind of system lag I am not aware of?Colossal Cannon: Building a behemoth piston-valved pneumatic

Posted by DeusXMachina 10 years ago


A Tony Stark(Iron Man) Chest Cooler/Fridge?

Has anyone tried to make one of these coolers that tony stark has?  Or even so, any ideas on how to make one? he opens it up and the drinks and glasses raise up like they are on pistons of some sort. I would love to make something similar to this, if not the exact same. So Suggestions? Ideas?

Posted by valmont325 7 years ago


Kitty Crack, Steampunk Keyboard, Raising Chickens

Kitty Crack Steampunk Keyboard Raising Chickens LEDs for Beginners Frozen Fruit Pop Tetris Bookshelf Gooey Chocolate Cake Make a Fire Piston Commodore 64 Laptop LED Glowing Shoes USB Contest Winners Elderflower Cordial Make a Toy Catamaran Multi-Fuzz Guitar Pedal 6 Vaseline Tricks

Posted by randofo 7 years ago


Shopping Bags to Frisbees

Someone once told me that about the only way to join polyethylene plastic was with heat and pressure. Plastic shopping bags are a recycling problem.  I think they are polyethylene plastic.  Heat and pressure might turn them into Frisbees, or other essential things.  I visualize a vertical, heat-resistant cylinder with a removable  Teflon-coated bottom cap in the shape of a Frisbee -- black to absorb solar heat.  A piston inside with the other half of the Teflon-coated mold could have a weight on it to provide pressure.  Fill the cylinder with shopping bags, with the piston inside, and suspend it over a solar reflector to heat the end cap of the cylinder.   There you have heat and pressure -- and free energy to turn the shopping bags inside into Frisbees, or other objects. Personally, I don't have need for more Frisbees, and don't collect enough bags to keep the equipment busy.  On a community recycling scale, though, it might be a way to get rid of a lot of bags that nobody wants.  Would anybody like to run the experiment? 

Posted by Thinkenstein 7 years ago


Has anyone made a solar heat powered Fluidyne stirling engine air pump?

So, I will start with what I have in mind.  (Might be total rubbish because I don't fully understand).  You have a solar collector box, not more than 1 meter square.  painted black 1 to 2 cm deep,   and probably with glazing over top. The box itself is metal fully closed up and the back is insulated.  From the box through the insulation there are some metal tubes that go to another box at back for the cooling chamber. Tubes are constricted so the air sprays through to the cooling box and it goes into steel wool as it expands. On the reverse stroke, it does not go so much through the steel wool because the nozel constriction is  on that side not the hot side.   Power is taken away from a liquid piston somewhere attached to both chambers  or a diaphragm at the back. (It can be water cooled). I want the strokes to be long and slow. Can it work?   Temp difference will only be around 40 degrees C and the pumped air ( 2 valves  in chamber off of liquid piston) only needs to go to 2 psi. )    I have been in contact with a guy in Germany who made Sterlings that worked with sun heat.    But he didn't use Fluidyne (also called liquid piston stirling) and he did not pump air.          My specs are extremely low, I only need 60 litres per hour of air at 1 or 2 PSI.  It would be very cool to make it from such basic materials.                 Thanks Brian

Posted by gaiatechnician 5 years ago


flame thrower

Ive seen this guy with a knex flame thower, then 2 months later the genius built a lego flame thrower.what do you think? can you build it? if so please post it. sorry i couldn't you the vids, cameras bit went funny mind you nothing melted for fve mins on going pumping. know it uses a piston sorta thing in both. squirting oil, a wick at the ignites it out come fire. something an acnient chinese flame thrower.

Posted by rde 10 years ago


Paper two stroke hydrogen engine

 Ok so I have this crazy idea to make a two stroke engine out of paper that runs on hydrogen and well ive allready built part of it just the piston head and cylider and stuff but if i lined the inside of the cylinder with tin foil would that be enoth to keep the paper from burning? and so ya anyways the engine of i have made allready is very sturdy each peace is 10 sheets of paper or more compressed for over 24 hours  now the compression im not two worried about because its more of the sheer pop of the explosion that will push the piston down well i guess thats how it is anyways but if the gas ignites anyways with oxygen why have compression  for this anyways because the explosion is going to be soooo small anyways that it wont really matter much.  the overall size of the engine is about almost 2" tall by about 1" wide on the widest part the bottom . So um I know by now im classified as "CRAZy" but that asside can i get some opinions and ideas plz. thanks MRN

Posted by mrn 8 years ago


Charging mobile from a steam generator

Hello Guys For my first attempt at building something I'd like to try a simple steam generator using a can, tea light etc set up. Would it be feasible to attach some kind of wheel / piston to a dynamo and to generate a small current enough to charge a mobile phone? Finding the correct search terms, when you're not sure which parts you need is a problem. so if there are some specific part names i could search for, that would be good. P

Posted by pbryd 3 years ago


Custom Wii Gun

I remeber back to the summer I was at an arcade playing Ghost Squad. Now that it is out on the wii, the fun was only half way there. I played with the wii zapper, and as much fun as it was, it just isn't cutting it. My favorite part was the force feedback gun that gave some recoil. I decided to go making my own, but I can't think of something to give enough punch. I plan to make a PVC gun outline and encase the wii remote. I would then rig a trigger on the PVC rifle to pull the fire button on the wii remote. From there, I could connect the wires so at a certain point on the PVC trigger pull, an electrical current would be completed activating the recoil. I started with thinking about takeing out the rumble motors in some old game controlers, but that would only go so far. I really wanted a staight back and forth movement. I started to think about taking a piston similar to an airsoft gun, were the motor cranks a gear that pulls the pistion back. This gear as some teeth shaved clean so that after so far of an extend, the teeth would inentially slip causing the built up spring to push the piston back into the starting position. Before it got too complicated and I started to build it, I wanted to make sure this was possible. Is it possible/practical? What type of feedback should I use, and were can I get it? -John

Posted by anotherkill 10 years ago


pedal powered tractor

I'm no designer but here's an idea I've been stewing on for some time. I've hunted but not found any designs for a pedal powered tractor. The very early tractors were very large;could to lots of work; but they only had 2 or 3 horsepower. They ran so slow you could count the piston strokes. The designs were simple and they were work horses. Our new high horse powered gas tools often cann't do nearly as much. The old machines used heavy flywheels; slow to start but they kept on rolling. With the improvements we've made in bike gearing systems why not make a pedal powered tractor that could do serious work with that same heavy flywheel technology?

Posted by Michael Fletcher 11 years ago


free energy (almost)

Wood powered air compressor 15 to 20 feet high, have not added the valves or pistons or gears but i thought this idea up today and felt like sharing it, last month I posted an idea about using steam pressure to pump water vertically and with the right configuration a header tank might be able to be adapted to work this contraption, using kinetic energy with a spring on the main arm and the weight of water to operate the arm to drive pumps. I dislike seeing fires go to waste and theres only so much damper you can cook. its the first time ive attempted to upload a movie, hope it works otherwise this message is pointless.

Posted by QSDR 5 years ago


Trombone Tree/Shrub Sprayer

We have low water pressure and a hose end sprayer doesn't reach very far.  I have been looking at Trombone Tree Sprayers in gardening magazines and though there must be a cheaper alternative.  Surely something could be made out of PVC and o-rings and some tubing. The sprayer seems to really be some sort of piston pump, kinda like a bicycle pump with a valve that draws water through a hose where the end is placed in a bucket of the liquid you want to spray.  You push the one tube into the other and is sprays about 20-25", kinda the same montion a trombone player uses. Anyone got plans or an idea on how to make this? Thanks in advance Danneauxs

Posted by danneauxs 8 years ago


Can Non-Hybrid Cars Get 100+ MPG Today?

  We're not talking about hybrids here; our topic is cars powered by the basic IC-engine that relies on gasoline and not electric motors. Today's gasoline engines are not designed to combust/burn gasoline efficiently. Even with the advent of using high pressure fuel injection techniques that are computer controlled, we still fall short of the mark. Partly because liquid gasoline can't burn, only gasoline vapors burn, and there lies our problem. The same goes for injecting the high pressure droplets of fine-mist liquid gasoline that enters the engine cylinder using our current nozzle ejector technology, it doesn't all burn at the same time! Engine designers assume that these droplets are instantly vaporized by the engine's hot cylinder walls, and then instantly explode/combust when ignited by the sparkplug. Not true, up to 2/3 of the fuel isn't vaporized and doesn't combust until later on in the cycle. The 1/3 that gets almost-instantly vaporized and burns will do so within the several thousandths of a second (Fig-1) it has before the piston moves down its 1/2-stroke (out of today's 4-stroke cycle) completing the engine power-portion of its cycle. This releases power and tremendous heat which indeed vaporizes the remaining ~2/3 of our fuel from its liquid droplet form, but too late. It essentially does so when the power stroke is almost over or the piston is just about ready to move into its up-stroke (2nd stroke of our four stroke cycle) phase. So, because of poor vapo-timing we have 2/3 of our fuel virtually wasted by exploding at near the bottom of the power stroke. This incorrect explosive timing, which happens to most of our fuel, imparts very little energy into the crankshaft because its effective "moment" (a product of explosive force and radial-component distance from crankshaft center) is insignificant by then. Various attempts at adjusting the combustion timing spark hasn't made a significant difference. Even though ~2/3 of the fuel is now exploding and providing a huge force, its small "influence" arm distance is rapidly diminishing to zero, and any huge downward force times near zero arm-length is still zero. Some clarification here, technically thermal-efficiency is not improved, pretty much all of the gasoline gets combusted today. That means the energy of the fuel is almost totally released, but not effectively used. The problem is the timing it takes to convert fuel-injected gasoline droplets into vapor to combust at the correct engine rotational time and extract that expended energy. If you did the math for any size engine rotating at say 3200 RPM, you would find that a 4-stroke engine can only extract that energy from combustion during one of the four strokes. And the time it takes to make that stroke happen is only about 9.4 thousandths of a second or 9.4 milisecs (msecs). Now picture the piston just below TDC, all its valves closed, under pressure and containing all the fuel and air it needs to combust. At this point our deadly cocktail has about half of the 9.4 or about 5 msecs to complete combust after the timed sparkplug ignites it. The half factor exists because the max portion of our power stroke (moment arm) occurs at the mid-stroke of the piston sliding down and turning the crankshaft. If all of our fuel isn't combusted by then, the moment-arm or distance from the piston-center to the crankshaft quickly reduces to zero. Again, only vapors combust within a healthy 2 msecs (Fig-1), while fuel droplets take a relatively long time (>5 msecs) to vaporize before it can combust. Unfortunately nature is stubborn and vaporizes ~2/3 of our injected fuel droplets only during roughly the second half of the power stroke. So this huge amount of energy gets wasted because even though the forces of combustion are huge, its moment arm is rapidly approaching zero. Infinity times zero is still zero! Engine designers/engineers have been plagued by this phenomenon ever since the creation of the 4-stroke gasoline or Otto cycle engine. We need to improve this intermittent combustion/explosion process by combusting all of our injected fuel at the correct timing sequence. This is accomplished by injecting only vaporous fuel which will produce ~3X the power we now get. Another way to state this is, for the same power that we now get from a gasoline engine, if we burned the fuel correctly, we would only need 1/3 the fuel consumption to get 3X the current MPG.

Posted by RT-101 6 years ago


Gasoline-powered, but no wheels...

I heard about them, but I thought they were a joke.Then I ran across a link.They actually made gasoline-powered pogo-sticks that even grandpa can ride!It's a single-cylinder engine, with the bouncing foot being connected directly to the piston, called the Hop Rod. There are a bunch of adverts and slightly more modern test-drives in a short video on the site.They're... odd.Still, I wondered. Maybe the Hop Rod provided the inspiration for other wheel-less powered transports?Do you remember those Russian boots? 4 metre strides and speeds of 40kph were promised, but that was 8 years ago. According to The New York Times they fell foul of Soviet secrecy and then Russian financial mis-management.They're still around, waiting for some entrepreneur to hop on the band-wagon...

Posted by Kiteman 10 years ago


Coke and Mentos Powered Car

Eepybird, the "Coke and Mentos Guys" used 108 2L bottles of Coke Zero and 648 Mentos to propel a car/bike 221 feet! An explanation of how it works, from their YouTube video: "The Coke Zero & Mentos Rocket Car uses a piston mechanism: a six-foot long rod sits inside a six-foot long tube attached to each bottle of Coke Zero. When the Mentos drop into the soda, the pressure tries to push the rod out of the tube. With 108 rods all pushing at once, that gives us a lot of power. All that power is pushing against a wall braced with 3,600 pounds of cement blocks. So all the force is directed into moving the Coke Zero & Mentos Rocket Car forward. We get one big push for six feet, and then it's all coasting from there."   via msnbc

Posted by Jayefuu 8 years ago


1000mph car to be powered by rubber and hair-dye.

The largest rocket fired in the UK for two decades will be lit soon, in the race to produce a land-vehicle capable of 1000mph. It will burn a mixture of solid propellant (HTPB, or hydroxyl-terminated polybutadiene, a kind of rubber) and liquid oxidiser (high-test peroxide, HTP, a highly concentrated form of hair-bleach) for 20 seconds. The Bloodhound SSC will also be powered by a jet engine from a Typhoon fighter. In the 20 second burn, the rocket will need fed with a tonne of HTP, so the pump is being powered by a Cosworth Formula 1 engine, which will become the only piston-engine running in a car at supersonic speed.  The team are planning to give the engine a major power-boost by feeding the supersonic airstream into the engine without slowing it to the usual operating speeds. The huge engineering challenges are being used to inspire students through the UK's STEM programme.

Posted by Kiteman 7 years ago


How to build a wifi or bluetooth capable button pusher for turning on computer from a distance?

I have been googleing this like crazy and cannot find anything close enough related to what I am trying to do.  I would like to be able to (ideally) use an iphone or ipad to send a wireless signal to a circuit board that then tells a piston (button pushing) mechanism to push the cylindrical on button on my computer.  It doesn't have to be a wireless signal, I could settle for less considering my lack of expertise in the area.  I am however confident in soldering and some scripting, which I thought about using a raspberry pi might work for this, especially for the wireless part of the project, but I would prefer still something with even less overhead.  If anyone has any ideas or direction that would be awesome.

Posted by zcmcc 5 years ago


Revolutionary Pen Idea

This morning I had an idea. Last night I was dissassembling a huge bagful of insulin pumps (my cousin is a diabetic and he uses them, cleans them, and gives them to me to take the guts out of them) and in them I keep the springs, casing, and insulin resevoirs... (I ALWAYS throw those horrid needles away; I don't want to get stuck with one) I had an idea looking at the resevoirs... I wanted an ink pen that could write/draw in ANY color ink with the turn of a dial, adjustment of a slide, etc.. anyway, I have about fifty of these resevoir things (they have little pistons in them) and I was curious if there was a way to reach my goal. Should I use red, blue, yellow ink, or should I use magenta, cyan, and yallow? Do I have to make the inks myself, or could I drain them from printer cartriges? Should I use only primary colors, or secondary colors as well?

Posted by MattGyver92 9 years ago


Movable Solar Panel:- Sizing limits.

Hi folks looking to build a tracking solar panel for North and South directions. I have a few drawings made up but im stuck for the maths side of things as I have a size limit I need to stick to in. I need the panel to move by 15° towards north and towards south. So a 30° movement in total. What I have in mind if an arch where the panel will sit on which can be moved with a single piston placed on the South end of the panel. This is to contract and expand to move 15° up and 15° down. My size limit is the panel must not exceed 200mm or 20cm in real money when at its maximum positions. I have assumed a 2 meter long panel (or array of panels in a frame) So because of this im a bit unsure about how to tackle the maths side of things to work out the arch's profile to meet this criteria. Anyone got any words of wisdom? The 200mm limit is the max UK law allows me to play around with the panels maximum position.

Posted by apmaman 3 years ago


Looking for more info on dish actuator

I received a free actuator from my friends cottage. 11 years ago it use to angle a 8ft dish. It was removed some time ago, and the label is fully off. The bottom says its a saginaw performance pak actuator, aka PPA, and it has a 24" arm. I was trying to find more information on it, and all I can find is that it can be heavy, regular, or light, 600-1,500 pounds dynamic linear. Anyone have one or any ideas? I cant find a model number on the case cuz it faded, but the motor says 7821645 or 1821645. Either way I found a tiny chart listing models but not that one.http://www.galaxy-marketing.com/images/7822260.jpgLooks similar to that one there. I just want to find out how much force it has. Most I done so far to test it works aftter 11 years of rusting on the main shaft (the moving piston is fine) is sit on a box. It manage to push me with no change in motor sound. Any more details? Please ask!

Posted by Killa-X 9 years ago


Do any big makers or instuctablers live near me?

Hey I was wondering if any big makers or instructablers on this site live near me. By big I mean professionsal makers and stuff, the famous instructable members who everyone has seen their ible's and knows about. I recently saw someone's ible' with an enormus air cannon using a piston valve and some of the pics in the ible' looked like they were from around here. but they weren't.             I need someone who knows alot about airguns, valves(homemade or bought), patatoe guns, compressed air ect. That type of thing because my "career"(not a career cause im a minor but you get it) in making air guns has come to a hault when I encountered two big problems that prevented me from making my guns any  bigger or my valves faster so I'm stuck Anyone who has knowledge in that feild or who lives around me please PM me and comment I live in rochester hills michigan

Posted by ostomesto 7 years ago


Murphy style beds mechanism

Hey guys, I need some advice, I want to build a murphy style bed, in short i want the bed to look like so: http://www.resourcefurniture.com/space-savers/queen-space-saving-beds/ito I have build and tested the shelf.leg system, it works pretty well and is weighted out nicely. the concept is going to use pistons to lower the bed for a smoother feel but what my concern is what would be the best way to build the pivot mechanism at low cost but high durability. the bed will have a sofa at the front also but not like the one in the link, my version will be more of a box with cushion and fabrik that i can store items away into. Please use the link below to view a version of my concept for the pivot mechanism: http://img21.imageshack.us/img21/692/pivotsystem.jpg ( i know there are a few misspelt words but it was just a quick mock up for you guys) Any help is welcome - just dont advise me to buy the murphy bed mechanism as its to expensive and i believe i can build the entire bed for the same price :)

Posted by rron.r 6 years ago


Update: Help Needed- Land Mine

This is kind of a spur-of-the-moment thing, but an idea for an airsoft land mine just popped into my head. I already own a land mine, but it is horribly ineffective. It shoots baking soda barely an inch off the ground. People easy claim they did not get hit, and it's hardly realistic. I could use your help building this. I only came up with a design, but not how get it to actually work. The *crudely drawn* design is below; it involves the unwitting victim stepping on a pressure sensitive plate. This plate triggers four air cannons buried in the ground loaded with baking powder and BBs. This hopefully blasts out in a much more realistic and impressive burst, and the victim knows they are dead. Any ideas on how to get it working?Here's another idea: make it spring powered. Saves the hassle of trying to build an air compressor. Place a spring in a pipe, attach it to a locking mechanism that releases when stepped on, place a platform on the spring. It would be kind of like a piston. (See second *crudely drawn* schematic.) It's ALIVE!. I made the switch to spring powered, and the prototype worked! It shoots BBs 28 feet and baking soda about 4 feet. Now I need to improve it and make an Instructable.

Posted by Spl1nt3rC3ll 10 years ago


Knex Safe (TGKTR2 Entry)

Alright! This is my safe. And a safe safe it is too! Me and a few other people noticed the irony of a knex safe, because you could just take it apart. Not so with this one! I made it with stupidly thick and Hard-to-take-apart walls, so as you would really need to work to get it open. The only piece you could break off are the pistons coming out the side, but then you've ruined the mech, and it wont work at all. However, there is a snag. The actual pin that goes into the door could not be finished on time. Everything else is here though, and I hope to get it finished up very soon. Sorry about that! The deadline sneaked up on me... So thats prettymuch it! Hope you like it. I have a video of the mechanism, but its not uploading. I should have one up tomorrow. EDIT: For all you folks bugging me to post (you know who you are...), let me give you the scoop. I am currently building a new safe. It should be stronger than the last, smaller, and cleaner. Please be patient, I will post when I can, bugging me about it wont make the time go any quicker. Thank you.

Posted by I_am_Canadian 9 years ago


Looking for adjustable accordion arm

I recently had a great idea for a completely useless, yet hilarious project for me to work on, but I am stuck on a single piece.The end result is a joke device that uses one of those accordion, spring loaded boxing gloves controlled over USB (the idea came about in a discussion over the universal wish to punch idiots over TCP/IP). To understand what this is, you'll have to think slapstick comedy and saturday morning cartoons (of the Wile E. Coyote variety). It sort of looks like this but replace the lamb with a boxing glove, and when extended looks like this: XXXXXXXX. Imagine the coyote opening a door that he expects the Road Runner to be behind, and out pops a boxing glove on an accordion arm that hits him in the face, making those little roadrunners circle his head.I suppose I could make one out of some material (metal, plastic, wood?) but I don't have much in the way of fabrication facilities in my new apartment. The best outcome would be if I could get such an arm off of an existing device.Sure other things could work (a piston for example), but the look of this project is very important and an accordion arm is a requirement to that end.Any idea on how to go about building/obtaining such a thing? I can't even figure out what to use as search terms.

Posted by opqdan 11 years ago


Launch It! Challenge Results!

Instructables is happy to announce the winners for the Launch It! Challenge. We saw some amazing entries that showed creativity and power. Once again, you showed us that there are people making cool things all around the world. These Instructables should serve as inspiration for others for a long time.Stay safe, everyone.Ratings Prize: FirstThe Instructable with the highest rating will receive a gift certificate for a Instructables Robot t-shirt from the Instructables store, and a custom-engraved Leatherman. Launch It: Patriot Model Rocket by kruser495Ratings Prize: Runners-UpThe 5 Instructables with the next-highest rating will each receive a gift certificate for a Instructables Robot t-shirt from the Instructables store. Golf Ball Gun!!! How To Make One That Can Shoot 400+ yards! by MrCrowley 25MM Pneumatic Sniper Rifle by irwinner Piano-wire Slingshot by chluaid Colossal Cannon: Building a behemoth piston-valved pneumatic by DeusXMachina The EasySling by -insertnamehere-Page Views Prize:The Instructable with the greatest number of pageviews will receive a gift certificate for a Instructables Robot t-shirt from the Instructables store, and a custom-engraved Leatherman. How to Make Fireworks by pudi.dkRandom Prize:We randomly picked one Instructable to receive a gift certificate for a Instructables Robot t-shirt from the Instructables store, and a custom-engraved Leatherman.Watch the video to see the winner: OK, here it is: Pencil Crossbow by marc92

Posted by fungus amungus 10 years ago


My Entry for the Gift Exchange

I have deiced to send Norbert and (one mystery item) to a good home... My skills include: Sewing, creative knot work... cakes and baking What I'd like to make for someone: (Pre-made cuddly squid) miniature Trebuchet... and something else when I put my mind to it (if this is not ok... I will re-edit this post) I'd be willing to make this size gift package for someone (choose all that apply): (S,M,L)... Small/Medium I'd be willing to receive a smaller or larger size gift package from someone than the one I make for someone else: Yes What I like: Anything thats usefull in the out doors... gizmo's and gadgets & things erlating to the Scouts. Knives and axes... What I don't like: nothing to high tech... Certainly not a Knex fan (or how ever you spell it... that plastic stuff that clips together) I absolutely can't have: (due to allergies, pets, etc) Type of thing I'd love to receive:I would LOVE a working fire piston but i think the thrill of just getting something suprising would be ace! Just so long as the item is usefull... :D Would you be willing to ship to an address outside your own country? yeah sure Confirm that are at least 18 years old or, if not, that you have the approval of a parent or guardian: I am well over the age of 18 Any problems let me know... pics added of what i shall be sending (pluss a mystery gift of whomevers choosing)

Posted by Biggsy 8 years ago


Wanting to go out with a bang

Alright, I'm sure you guys get the message, I don't build much lately. I think I might stash away the K'nex soon (I'll still stick around) but I feel bleh that I haven't actually posted anything in forever. I was going to get more images of the UMP-45 but I ended up mutating it into a non functioning modelish gun while I was bored and it'd take work to regut it so hopefully someone figures it out from the two pictures I posted. It's really not that hard. Anyways, to the point. I still have that idea floating in my head from over a year ago that no one has been able to help me with yet. Basically, it's a fully automatic gun that doesn't require a motor, and it'd get decent range. The concept is pretty much to modify an RBG type gun to work with a piston system like the ones in modern firearms. It should have a controllable RoF then. The problem is that I still need a good RBG mech! It's funny how tricky it turned out to be. I need a cog/gear and trigger system that takes little effort to operate. This means that you'll need to somehow minimize the friction between the trigger and whatever is holding the rubber bands. If it's sensitive enough, the rest should be simple. But grr people keep leaving and I need someone who can make such a mech to MAKE IT ALREADY! I've tried so many times myself and failed but I'll give it another shot. It's essential before I can move on to the rest of the design.

Posted by TheDunkis 7 years ago


(newsletter) Cheap Screenprinting, Bike Boombox, Pi Day...

Sign-up for this newsletter: function openSubscribePopUp(src){ var emailValidate = /\w{1,}[@][\w\-]{1,}([.]([\w\-]{1,})){1,3}$/ if(emailValidate.test(src.value) == false){ alert("Please enter correct email"); return; } window.open("/newsletter/newslettersignup?email=" + src.value,"newslettersignup1","status=yes,scrollbars=yes,resizable=yes,width=420,height=250"); } We're now running THREE awesome contests, so get to work on your Instructables! Burning Questions is back with a vengeance. Answer our questions and win the love of thousands, or at least a spiffy new t-shirt! ThinkGeek Hacks Contest is now open for those of you who enjoy modifying the things you buy. Hack or modify anything from ThinkGeek and win a $250 gift certificate!Epilog Challenge is still open for entries. Enter your project with a green twist for a chance to win an Epilog Zing laser cutter or a gift certificate from Ponoko!Klutz Rubber Band-Powered Contest is almost open for your rubber band-powered contraptions! Win cool books from Klutz! Pi Day Guide Screenprint for Less Than $10 Make a Soil Blocker Build a Music Studio in an Apartment Win a laser cutter! Stretch, twist, and power something cool! (almost open) Build a Bike Boom Box Steampunk Clockwork Piston Turn a 300 Watt Lamp into a 20 Watt CFL Reconstructive Surgery for a Suitcase Get a free Expo Pass or save 35% on Conference registrations for Web 2.0 Expo San Francisco! Featured questions from our new Answers section: How do I build an audio amplifier circuit?Is there an affordable way to wireless stream audio from my laptop to my speakers? Oobleck: Gooey Science Experiment Build an Inexpensive Ikea NAS Make an Automatic Plant Light Spraygun 101 Let your geekiness shine! Get your green ready! Master a Perfect Inline Wire Splice Greenhouse From Old Windows Optical Illusion - Mysterious Black Dots Three Part Clock Sign-up for this newsletter: function openSubscribePopUp(src){ var emailValidate = /\w{1,}[@][\w\-]{1,}([.]([\w\-]{1,})){1,3}$/ if(emailValidate.test(src.value) == false){ alert("Please enter correct email"); return; } window.open("/newsletter/newslettersignup?email=" + src.value,"newslettersignup1","status=yes,scrollbars=yes,resizable=yes,width=420,height=250"); }

Posted by fungus amungus 9 years ago


Sandia, Stirling Energy Systems set new world record for solar-to-grid conversion efficiency

31.25 percent efficiency rate topples 1984 recordALBUQUERQUE, N.M. --On a perfect New Mexico winter day -- with the sky almost 10 percent brighter than usual -- Sandia National Laboratories and Stirling Energy Systems (SES) set a new solar-to-grid system conversion efficiency record by achieving a 31.25 percent net efficiency rate. The old 1984 record of 29.4 percent was toppled Jan. 31 on SES's "Serial #3" solar dish Stirling system at Sandia's National Solar Thermal Test Facility.The conversion efficiency is calculated by measuring the net energy delivered to the grid and dividing it by the solar energy hitting the dish mirrors. Auxiliary loads, such as water pumps, computers and tracking motors, are accounted for in the net power measurement."Gaining two whole points of conversion efficiency in this type of system is phenomenal," says Bruce Osborn, SES president and CEO. "This is a significant advancement that takes our dish engine systems well beyond the capacities of any other solar dish collectors and one step closer to commercializing an affordable system."Serial #3 was erected in May 2005 as part of a prototype six-dish model power plant at the Solar Thermal Test Facility that produces up to 150 kilowatts (kW) of grid-ready electrical power during the day. Each dish unit consists of 82 mirrors formed in a dish shape to focus the light to an intense beam.The solar dish generates electricity by focusing the sun's rays onto a receiver, which transmits the heat energy to a Stirling engine. The engine is a sealed system filled with hydrogen. As the gas heats and cools, its pressure rises and falls. The change in pressure drives the pistons inside the engine, producing mechanical power, which in turn drives a generator and makes electricity.More here:http://www.sandia.gov/news/resources/releases/2008/solargrid.html

Posted by ewilhelm 10 years ago


Convert airgun/Paintball gun to be fired by a computer (12v solenoid valve)

Hi!I have a project this summer where I need to convert a paintball marker and a co2 Airpistol to be fired by the use of a solenoid valve powered by 12v.The project goal is high-speed photography, more or less photographing object being hit by a projectile.What i need is a way to fire these guns precisely by the use of my computer and software, and since I already have plenty of 12 solenoid valves that work with this system I thought my easiest way is to adapt these valve to trigger the guns one way or another.I just purchased a Valken V-TAC SW-1http://www.valken.com/Marker-V-TAC-BLACKHAWK which I plan to use as base (for parts) My reason for getting this particular one was that it was on sale for 50% and seems to be fairly popular as it's based on the Tippmann 98 design.I attached an image of the valve I used with my controller and software (Cognisys Stop shot) now I can probably use any 12v solenoid valve (with the same spec ?) as the one I use now so it doesn't need to be these exact valves. As long as they can be operated by turning on-off power with the same powersource i use to control my current solenoid valves.From my understanding, most airguns use a pin valve, which is hit by a trigger mechanism that is then rearmed by the blowback.What would be the best way to modify an airgun for my needs? Replace the pin valve with a suitable solenoid i can control instead? Or go for a design that uses maybe use a piston and 2-way valve to hit that pin?The gun does not need to be mobile or ergonomic, it will be placed in a rig regardless, however keeping the barrel and keep the Picatinny is preferred to be able to mount marking aids etc. and mount the gun to a tripod.Any tips or suggestions are highly appreciated!Thank you!

Posted by PaulL320 2 months ago


Barbie Electric Chair, Chaos Machine, Build a Pizza Oven...

Function clickclear(thisfield, defaulttext) {if (thisfield.value == defaulttext) {thisfield.value = "";}}Sign-up for our newsletter subscribe Sept. 6, 2007 Welcome back! We're seeing a few of the robots coming in from the iRobot Challenge this week as well as a variety of other cool projects. Check them out! How to Weld - MIG Welding A basic guide to the awesome process of using electricity to melt and join pieces of metal together.posted by noahw on Sep 5, 2007 PosterBot: Make a Marker-Writing Robot I always got marked down for posters that weren't "neat" enough. Like any nerd, I figured "If I can't do it, I'll make a robot to do it for me."posted by W_world on Sep 5, 2007 How to make Gingerbread Pumpkin Whoopie Pies Make a treat kids love in under 20 minutes.posted by DMR301 on Sep 5, 2007 Put an iPod Nike+ sensor in any running shoe in one minute for 5 cents Avoid buying specialized Nike+ shoes with this simple hack.posted by fungus amungus on Sep 4, 2007 How to build a Pizza Oven Create a functional piece of art for your backyard and start cooking.posted by t.rohner on Sep 2, 2007 Share your tasty recipe with us! Answer our burning questions! Get a free shirt! Make it fly! Barbie Doll Electric Chair Science Fair Project! This is a science fair project that I did in middle school and completely disgusted the entire female staff of Benton Middle.posted by jessyratfink on Sep 2, 2007 The Chaos Machine (Double Pendulum) Every physics department needs a double pendulum, so here's how to build one. posted by Luke Luck on Aug 31, 2007 Baby Space Invader Hat Let your little one go retro with this gaming-inspired knitting pattern.posted by tracy_the_astonishing on Sep 5, 2007 Golf Ball Gun!!! How To Make One That Can Shoot 400+ yards! Learn about pistons and pneumatics while firing golf balls through plywood.posted by MrCrowley on Sep 2, 2007 ServerBot - for serving food and drinks Create a robot that's helpful, entertaining, whimsical AND simply amazing. posted by JoeCreate on Aug 31, 2007 Now go build something awesome, and I'll see you next week! -Eric )))

Posted by lebowski 10 years ago


Make Fireworks, RFID Pet Feeder, LED Jellyfish Costume...

Sign-up for our newsletter here. Sept. 13, 2007 Welcome back! The iRobot Create Challenge has just finished up with over a dozen cool and we're still seeing some cool Launch It! Challenge entries come in on top of the usual cool projects. Check them out! Halloween LED Jellyfish Costume Using LED rope lights and a plastic washing basin to create a deep sea bioluminescent jellyfish thing.posted by deadinsect on Sep 11, 2007 How to Make a RFID Pet Food Feeder Make sure dogs aren't stealing food with an RFID alarm.posted by mlarsen on Sep 5, 2007 Creative Discontent: Squalk (Squirt Chalk) Non-destructive communication tool for mass public discourse. Erasable graffiti at its finest.posted by pdip_stiffi on Sep 9, 2007 How to Make Monkey Bread The ultimate finger-licking, finger-picking dessert of all time. Soft balls of dough, coated in a cinnamon sugar crust of sweet goodness.posted by trebuchet03 on Sep 9, 2007 Colossal Cannon: Building a Behemoth Piston-Valved Pneumatic Launcher Sometimes you think to yourself, "Hmm...I wonder just how far I can hurl stuff, maybe even into the next county." posted by DeusXMachina on Sep 9, 2007 Contest ends on Sunday! Answer our burning questions! Get a free shirt! See who won the $1,500 top prize! How to Make Fireworks Learn how to make your own aerial shell and wow the neighbors.posted by pudi.dk on Sep 7, 2007 eyeRobot - The Robotic White Cane How to hack an iRobot to guide blind and visually impaired users through cluttered and populated environments.posted by shrimpy on Sep 8, 2007 Piano-wire Slingshot A small but powerful slingshot made using 1mm gauge piano-wire and ordinary rubber bands.posted by chluaid on Sep 9, 2007 Gliding/Floating Laptop Dock A floating laptop dock that moves back and forth, eliminating the need to station the laptop on your lap. posted by Romado12187 on Sep 8, 2007 How To Build A Pit Oven (And Cook A Salmon) Learn to do a little backwoods cooking with a pit oven. posted by Mr. Nova on Sep 11, 2007 Now go build something awesome, and I'll see you next week! -Eric

Posted by lebowski 10 years ago