Search found 54 matches

by Hopper
Thu Feb 28, 2013 9:01 pm
Forum: Stirling and "Hot Air" Engine Forum
Topic: Sterling(beta) refuses to work at all after 7 builds.. Help!
Replies: 91
Views: 34189

Re: Sterling(beta) refuses to work at all after 7 builds.. H

Yeah the scrap to power crankshaft looks more complex because is has two connecting rods to the diaphragm. He says in there that the crank throw for the displacer should be about 20mm and for the power diaphragm about 5mm. So that gives a stroke of 40mm for the displacer and 10mm for the diaphragm. ...
by Hopper
Thu Feb 28, 2013 7:32 pm
Forum: Stirling and "Hot Air" Engine Forum
Topic: Sterling(beta) refuses to work at all after 7 builds.. Help!
Replies: 91
Views: 34189

Re: Sterling(beta) refuses to work at all after 7 builds.. H

I got to tell you man, that was an awesome answer! Lord knows it seems the sudo "rules of thumb" where nowhere to be found! If this was yahoo answers you would take the cake. Thank you to the bearer of knowlage. Like I said though, don't think you can take those rules of thumb and apply them to tin...
by Hopper
Thu Feb 28, 2013 6:41 pm
Forum: Stirling and "Hot Air" Engine Forum
Topic: Sterling(beta) refuses to work at all after 7 builds.. Help!
Replies: 91
Views: 34189

Re: Sterling(beta) refuses to work at all after 7 builds.. H

There are a few rules of thumb floating around, based on what the original Mr Stirling wrote and what has been found since, BUT many working engine plans do not follow those rules of thumb but were found by trial and error by guys who developed their own plans. The "Tin Can" engines seem to vary fro...
by Hopper
Tue Feb 26, 2013 9:04 pm
Forum: Stirling and "Hot Air" Engine Forum
Topic: stirling engine isnt a heat engine?
Replies: 8
Views: 5004

Re: stirling engine isnt a heat engine?

When you add ice to a Stirling engine you are not adding cold, just extracting heat. This allows more heat to be added from the atmosphere to the hot end. But you are right I think, no other engine can be made to run by taking heat away from it. On the other hand there ain't no free lunch. It takes ...
by Hopper
Mon Feb 25, 2013 2:17 am
Forum: Stirling and "Hot Air" Engine Forum
Topic: Sterling(beta) refuses to work at all after 7 builds.. Help!
Replies: 91
Views: 34189

Re: Sterling(beta) refuses to work at all after 7 builds.. H

What do you think determines the amount of "power" obtainable? Amount of temputure change, displacer size, crank throw measure or what's your best guess? All these things contribute to power, but they must be in the right proportion. Size of the diaphragm plays an important part to. More area = mor...
by Hopper
Mon Feb 25, 2013 12:40 am
Forum: Stirling and "Hot Air" Engine Forum
Topic: Does the Balloon need to travel same distance as displacer?
Replies: 9
Views: 4727

Re: Does the Balloon need to travel same distance as displac

This is a beta can engine. I'm trying to decide if my crank is right. If my displacer lifts 1.5in, should the balloon also lift that much in retrospect? No. That would be stretching the rubber too far. If the Displacer moves 1.5 inches, the rubber diaphragm needs to move about half an inch. So your...
by Hopper
Sun Feb 24, 2013 9:38 pm
Forum: Stirling and "Hot Air" Engine Forum
Topic: Does the Balloon need to travel same distance as displacer?
Replies: 9
Views: 4727

Re: Does the Balloon need to travel same distance as displac

Insainhouserecords wrote:This is a beta can engine. I'm trying to decide if my crank is right. If my displacer lifts 1.5in, should the balloon also lift that much in retrospect?
Probably not.
by Hopper
Fri Feb 22, 2013 7:29 pm
Forum: Stirling and "Hot Air" Engine Forum
Topic: Sterling(beta) refuses to work at all after 7 builds.. Help!
Replies: 91
Views: 34189

Re: Sterling(beta) refuses to work at all after 7 builds.. H

Or you could try a much shorter tin and a balsa wood displacer. Shorter tin = less air space = more pressure on the rubber diaphragm. Disposable latex gloves, the thicker mechanics type are used on some engines. See this one here for the shorter tin version: http://myfordboy.blogspot.com.au/p/myford...
by Hopper
Thu Feb 21, 2013 6:59 pm
Forum: Stirling and "Hot Air" Engine Forum
Topic: Sterling(beta) refuses to work at all after 7 builds.. Help!
Replies: 91
Views: 34189

Re: Sterling(beta) refuses to work at all after 7 builds.. H

With a swift spin on the flywheel with your fingers it rotates nearly 5-6 spins. I'm going to redo the displacer with a tighter fitting one and seal the top can to the bottom can other than that.. It makes no sense to me why physics aren't working. Displacer needs to be a loose fit, not tight. Air ...
by Hopper
Wed Feb 20, 2013 10:21 pm
Forum: Stirling and "Hot Air" Engine Forum
Topic: Sterling(beta) refuses to work at all after 7 builds.. Help!
Replies: 91
Views: 34189

Re: Sterling(beta) refuses to work at all after 7 builds.. H

No your not looking at the pictures correctly. The only real difference is your sides of the top can are cut out. My stand isn't pictured. The top can just holds the crank. The top cans bottom is the bottom cans top. OK, I get it now. IN that case it must be a matter of reducing friction and increa...
by Hopper
Wed Feb 20, 2013 9:51 pm
Forum: Stirling and "Hot Air" Engine Forum
Topic: Sterling(beta) refuses to work at all after 7 builds.. Help!
Replies: 91
Views: 34189

Re: Sterling(beta) refuses to work at all after 7 builds.. H

Here is the single-can engine I was talking about in the last post http://www.youtube.com/watch?v=U8dUL4z1Hwg As you can see, the elbow goes on the top can, flame straight under it. Second can is used only as a stand, not connected to the piston or displacer. Heres some vidoes on how to build them h...
by Hopper
Wed Feb 20, 2013 9:45 pm
Forum: Stirling and "Hot Air" Engine Forum
Topic: Sterling(beta) refuses to work at all after 7 builds.. Help!
Replies: 91
Views: 34189

Re: Sterling(beta) refuses to work at all after 7 builds.. H

No, you don't want the displacer to touch the can at top or bottom. There should be a small airspace space there. Likewise the displacer should not touch the sides of the can, there needs to be a small airspace all around so the air can flow past as the displacer goes up and down. I would question t...
by Hopper
Wed Feb 20, 2013 8:19 pm
Forum: Stirling and "Hot Air" Engine Forum
Topic: Does the Balloon need to travel same distance as displacer?
Replies: 9
Views: 4727

Re: Does the Balloon need to travel same distance as displac

Lol, there was no motor plan. I looked at the other engines being built and started to build from scratch under my own assumptions and common knowlage of physics. This may be your problem. There is more to these engines than meets the eye. Best to start with a tested and proven existing plan, then ...
by Hopper
Wed Feb 20, 2013 8:12 pm
Forum: Stirling and "Hot Air" Engine Forum
Topic: Sterling(beta) refuses to work at all after 7 builds.. Help!
Replies: 91
Views: 34189

Re: Sterling(beta) refuses to work at all after 7 builds.. H

Because the balloon is the energy transferer right? The balloon helps "push" the crank along with the flywheel. It's the only two spots recieving energy. The displacer is in a wire that falls on its own therefor cannot transfer energy upwards. Right? Yes. The displacer's only function in this type ...