Step 3: The Displacer

Roll the steel wire wool around a bic pen, when it's a little bigger then the can opening, stop rolling the wool and cut it to size. Cut it down to about 2/3rds of the height of the can. Thread the paper clip you formed earlier through the centre of the steel wire wool. Tie on about a foot of fishing line to the hook in the paper clip. Squeeze the displacer into the can. It's a tight fit, but it can be done

I gust watched tow helicopters go by woooooooooow
Trying to figure out why this engine runs is like figuring out why a bumble bee flys, it should not run but it certainly runs quite well. The counter weight in the center seems to resonate and the flywheel is low mass but high inertia. I am not an expert but there are principals at work here that need to be studied. This is a great example of thinking outside the box.
The principle is quite simple. If I may.... There is a displacer inside the can. <br>This displacer moves up to allow the air within the can to make contact with the hot can bottom. This expands the air which drives the diaphragm up due to expansion. The displacer then drops to the bottom of the can which insulates the air from the heat thereby allowing the surfaces not exposed to the heat to cool the air which allows the air within the can to contract. <br> The REALLY cool thing about sterling engines is if you drive the shaft instead of the other way around, it becomes a heat pump! Not bad for 1880's tech!
I did not see the fishing line going to the displacer in the movie so I thought it was resonating somehow. I still think it is a good design and would work with multiple cylinders. Perhaps an affordable and practical vehicle could be built using a stirling engine.
Very cool! We built it today. It took a little more finesse bending wire than I had anticipated. If you don't balance it well enough, it wobbles like crazy on the wire legs even if you're holding the base.<br><br>We added a 15 mm strip of wet paper towel around the top of the can to act as a better heat sink - it helped a lot. <br>Thanks a lot for the great instructable!!
Wooo! First person to build this ? Please share some photo's if you can :)<br><br>The paper towel is a good idea!<br><br>Thanks!
Middle School Science Fair, here I come!!!!<br>Awesome!<br>I had never even heard of a Stirling Engine until this instructable.<br>My kids and I will have a blast (in a good kind of way) with this.
I think it's AWESOME that you are introducing your kids to this! <br> Not only is this device classified as an external combustion engine and is truly a flex fuel technology which can even run on solar or geothermal heat. <br> In fact, any heat difference between the &quot;hot cap&quot; and &quot;cold cap&quot; will make it run. This goes all the way back to 1880's Scotland and I have read that it was devised to take the place of the dangerous steam engines used in coal mining at the time. Not a bad job of design by a monk of all people. <br> Ther is a wealth of history associated with this device. <br> One last thing, it has been said that this device is one of the most thermally efficient engines ever devised. Good luck with the Science Fair!
<p>Think more cylinders could be added?</p>
<p>We have built this 2 or 3 times now and it will not work. Project is due tomorrow. Any suggestions you can give me?</p>
<p>You have done really well here! You have taken what could be potentially a very complicated engine and made it very simple. What an achievement!</p>
can i use a steel wire instead of fish line and tell me how it works??????<br>
<p>I used dental floss - it's stronger than thread</p>
<p>Could somebody suggest an alternative to coat-hanger wire please? Steel coat-hangers are no longer commercially available in the UK.</p><p>I tried using a bicycle spoke but it was too hard to bend into the small part of the crank.</p>
<p>I just used garden wire - it's about &pound;1.25 from Wickes of a &pound;1 from Aldi (when they have it)</p>
<p>I tried and failed on first attempt....:-( I need urgently for school project.........pleeeez help ! ) </p><p>I couldn't get the connectors, so made eye hooks ...I read some where you said it adds to friction.....but mince rolled freely when fully connected up......</p><p>This time I will reduce the length between the two bearing points and see if it works......while trying I want to any other loop holes.......is it possible to test the movement of diaphragm by heating BEFORE connecting the cranks ?( It is very difficult to assemble w/o connectors ! ) It appears a bit stiff to me.....but it does rise almost a cm when pulled up. ....I saw the picture posted earlier where the pulling the fishing line brought the diaphragm up......it doesnt happen in my case.....is it OK ? </p><p>the diaphragm crank throw seems very small for the gas to move it....? As I understand this is what makes the crank rotate....I am using Aluminium PEPSI ( no steel cans where I live ) can I will add wet towel on top if required........lot of work for 5 hours and no result ......really hurts !!! </p>
Hai wit respect <br> I like to know if I can replace the 'fine steel wool' thing here. <br>I am unable to find it.and also can you suggest me a way to find it? please! <br> <br> thankyou
Would ring terminals do I couldn't find spade connectors
great instructable.one question.can i use cotton instead of steel wool?in our county steel wool is not available.so..............
Where and how does the displacer connecting rods go?
Very good concept. Trying to make it reality now.
Yes it is!
fantastic! i want to build one!
Just love it and I certainly must try it
Amazing work my friend!
Awesome work. Thanks for sharing it with the community.
Interesting I must say.Trying to make it now.
You are awesome and creative!
Excellent work!
I really want to do this project. I have all the things but the wire. Would paperclips work as wire? By the way, would a few drops of water make Stirling engines more effective? I know steam is 100 times the volume of water.
I wouldn't have thought paper clips would be long enough, even un-wound. You could try adding another coke can on top for the bearings like my other instructable &quot;make a coke can Stirling egnine&quot; . You can get this kind of wire at garden centres and the like, it's not usually expensive, don't get the really thin 1mm stuff though as that won't work. <br><br>My engines that have had small water leaks all splutter to a quick death, maybe it would work but you need to be quite precise in the amount of water :)
the paperclips worked for the crankshaft, I made a flywheel of cardboard and glued it onto the crankshaft. For some reason I couldn't get the engine to work.. I gave up on it...
Very cool! We built it today.
learn to measure <br>how does 15 cm get that far <br>you made me waste 30cm of wire.
oh im sorry i made the mistake <br>
Use it for the connecting rods.
I started using it for the stand and the loop above the basket &lt;:(
I almost id that too, but my base looks nothing like the picture, but does it work, yes.
I never did get that tin can working, but its cool
I have tried to assemble a Simple Coke Can Engine, but after several attempt, I failed, so please let me know how would you help me if i become a paid member.
Authors on this site are not paid, so being a paid member will make no difference.<br><br>Which steps are you having difficulty with ?
Amazing work have you done.
Thank you.
I found this project very interesting! Trying to make it now.
well i assembled the thing sadly it doesnt work, its my fault so i am going to see if i messed up with the counterbalace, and there maybe a lot of friction.
this is probable a dumb question bot what does the displacer do?

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