help needed

[ganuganu89]

Hello everyone here is a stirling engine made by me using deospray bottle and coke can. Used CD as flywheel and balloon as power piston, steel wool as displacer and fishing thread to hold the displacer. Take a look at the pictures.

I dont know why my engine doesnt run, oiled everywhere, sealed the engine using araldite, crank shaft was straight and timing is 90degrees, before testing the engine using candle initially i turned the flywheel it moved nearly 1.5turns(smoothly) and stopped. To my knowledge i made everything as it should but failed.

Can anyone please help me.

http://www.newgrounds.com/dump/item/d5f ... 8b91349fed
http://imageshack.us/photo/my-images/13 ... 12753.jpg/

[Ian S C]

Found your problem, if you put the conrod for the diaphram on the same crank as the displacer you will be OK, because if you have the diaphram at right angles to the displacer as you have, you only need one crank. Your crankshaft is designed for the two con rods running parallel. You could modify the motor so that the rod from the diaphram points up, parallel to the displacer rod, and use both cranks. Good luck Ian S C

[ganuganu89]

Found your problem, if you put the conrod for the diaphram on the same crank as the displacer you will be OK, because if you have the diaphram at right angles to the displacer as you have, you only need one crank. Your crankshaft is designed for the two con rods running parallel. You could modify the motor so that the rod from the diaphram points up, parallel to the displacer rod, and use both cranks. Good luck Ian S C

Thank you for reply, i will modify it soon and post it here. One question: why if i place power piston right angle to displacer, engine will not run? can you please explain the concept.

[Ian S C]

If you put the diaphram at right angles, and the second crank at 90* you make the phase of the motor 180*, 90* +90*. making a motor with the piston and displacer at 90* makes for an engine with the simplest crankshaft with only one pin. Hope this helps, Ian S C

[ganuganu89]

Here is the modification i have made for the engine. i will finish the construction by tomorrow need to buy terminal blocks tomo, after that a test run.

http://imageshack.us/photo/my-images/85 ... 12762.jpg/
http://imageshack.us/photo/my-images/80 ... 12763.jpg/

[Ante]

ganuganu

Can of axe deo-spray is tick aluminium can.
That types of can conduct heat very fast, besides it is relatively low, that means that temperature difference between top and botom is low.
My advice is if you measure (feel) high temperature on the top of can after short time of heating try to find steel can and replace it.

Some deospray cans are steel. You can recognize them by "FE" letters in sign for recycling

Salute!

[Junkie]

The position of the diaphragm is not important, so long as the crank shaft maintains the 90* difference.
This engine was built from around my ASAP plans I believe, if so the two most common problems people have had
are that the wire wool displacer is rubbing against the sides of the can preventing it from moving properly.
The other is that the hole around where the nylon wire exits is too large, allowing too much air to escape.
It should be a close fit.

Is there any reason you used two different size cans ? It's much easier to get and keep the engine airtight
if the two cans are the same size. If the cans are free from defects, there should be no sealant required.

Hope that helps.

[ganuganu89]

The position of the diaphragm is not important, so long as the crank shaft maintains the 90* difference.
This engine was built from around my ASAP plans I believe, if so the two most common problems people have had
are that the wire wool displacer is rubbing against the sides of the can preventing it from moving properly.
The other is that the hole around where the nylon wire exits is too large, allowing too much air to escape.
It should be a close fit.

Is there any reason you used two different size cans ? It's much easier to get and keep the engine airtight
if the two cans are the same size. If the cans are free from defects, there should be no sealant required.

Hope that helps.

Yes i referred to your engine's design, i dont have two similar sized cans thats why i used different diameter cans. I have posted the video in youtube please check this link. Here i didnt connect the displacer to the crank shaft instead i manually moved it to show whether my engine is working good or not. Please reply.

http://youtu.be/Ic-98iopJhs

[Ian S C]

You are lucky living in a place thats not littered by drink cans, I could go out now (it's a bit dark), and without trying too hard, pick up 20 or 30 cans from beside the streets, my town has about 2000 people in it, at least they are not as bad as the broken bottles we get (I ride a bike, glass/ tires don't go together). Ian S C

[ganuganu89]

hello everyone after a long time i made a new design but it got some leaks repaired it(pasted m-seal) at the point of leak. But the seal produces small amount of friction so i moved the displacer manually and to my surprise, the engine worked. Here is the link, soon i will post the video of the engine working by itself. This trial gave me some encouragement.

http://www.youtube.com/watch?v=IoluHLOa280

[ganuganu89]

I got it working manually, so i decided to make another one which works by itself but the problem here like previous design there is a leak at the hole where the fishing line comes out from the displacer cylinder. How can i seal it completely please help me.

[Ian S C]

The fishing line to connect the displacer obviously works, but I have my doubts about gravity beingentitely the answer to keeping the line taught, I think you would get more out of a bit of stiff wire, may be not much thicker than the fishing line. I think you would be able tohave a hole that fits closer than with the string. Ian S C

[Ian S C]

Amritachbe, your best bet would be to get some books, maybe from your library, or buy from a bookshop or on line, read them and understand the workings of the Stirling Engine, some of the books will have plans for building motors, some simple, going on to quite complex motors. After building a published design or two you will then be able to start thinking about designing your own, and if you have a problem just ask here and someone will do their best to help you. Mind you, I did it the other way round, I bought a lathe, and a vertical mill, then built a Stirling Engine, then got books on how to do it, although I had information I had got from "Model Engineer" magazine, it worked quite well, and I'v built a further 16 motors. Ian S C

[ganuganu89]

I made another stirling engine iam getting the same result can ANYONE PLEASE HELP ME HERE iam getting mad over this
It only works if i move the displacer myself, engine lacks in moving the displacer for itself. What is the reason for this? Anyone!!!!!

[Ian S C]

The next thing I would do is, get rid of the nylon connecting the displacer to the crankshaft. Replace it with wire, it needs to be ridgid. Make sure its straight, and smooth, a bit of coat hanger wire or similar, say 1.5/ 2 mm dia. Ian S C