Search found 66 matches

by SScandizzo
Sat Feb 03, 2007 12:52 pm
Forum: Stirling and "Hot Air" Engine Forum
Topic: heater fan
Replies: 1
Views: 3335

Hi Jhead, http://www.jerry-howell.com has some beautiful plans and kits available. I have never personally built any of them, but I think that they are some of the nicest looking Stirling engines available at the scale you are considering. You may need to have access to a lathe in order to build the...
by SScandizzo
Thu Feb 01, 2007 12:22 am
Forum: Stirling and "Hot Air" Engine Forum
Topic: why do most models have of displacer type piston?
Replies: 2
Views: 4941

Hi Ozzu, Great question! There are probably a number of correct answers as to why most practical versions of Stirling engines have only a "cold side" piston. I'll try to address a few. First, pistons must be in very close contact with their cylinder walls. This creates friction. Friction is bad beca...
by SScandizzo
Tue Jan 30, 2007 10:38 am
Forum: Stirling and "Hot Air" Engine Forum
Topic: It will not run.
Replies: 9
Views: 8424

TJ, If possible, place a counter balance on the fan so that the displacer stops at a random position every time you free-spin it. This will help balance the engine and prevent it from stalling at low speeds (such as start-up). Also, with low heat and the system closed, try spinning the fan. Does it ...
by SScandizzo
Mon Jan 29, 2007 11:34 am
Forum: Stirling and "Hot Air" Engine Forum
Topic: It will not run.
Replies: 9
Views: 8424

Here's the direct link to see the picture: http://www.stirlingengine.com/file-storage/download/DSCN2150.JPG?version_id=355 Wow, that's a big boy! Ok, so you mentioned that you do have compression and that the engine turns freely when the plug is removed. I'm still willing to bet that there is an air...
by SScandizzo
Fri Jan 26, 2007 11:09 am
Forum: Stirling and "Hot Air" Engine Forum
Topic: Power producing low delta T state of the art?
Replies: 11
Views: 9829

Hi Pete, I'd research both NASA and Phillips work to see how you stack up. Half a watt is quite an accomplishment at the scale you describe. I'm not sure if you meet the definition of a low delta T engine at 30C, though. I'll have to defer to someone else, but I believe at difference of less than 10...
by SScandizzo
Mon Jan 22, 2007 10:21 am
Forum: Stirling and "Hot Air" Engine Forum
Topic: It will not run.
Replies: 9
Views: 8424

Hi TJ, First thing I would do is take a look at the thread "little machine shop walking beam engine" because its about another engine that isn't (as yet) running. There are quite a few tips there to try. The only thing I will repost here is DO NOT over heat the engine. If it is not running with the ...
by SScandizzo
Wed Jan 17, 2007 11:03 am
Forum: Stirling and "Hot Air" Engine Forum
Topic: Flywheel
Replies: 12
Views: 10449

Brilliant! Thanks Cartech.

-Stefan
by SScandizzo
Wed Jan 10, 2007 6:35 pm
Forum: Stirling and "Hot Air" Engine Forum
Topic: little machine shop walking beam engine
Replies: 7
Views: 6558

Hi Larry,

The pictures came through just fine. I can't see anything obvious from the images, so I'm going to have to depend on your descriptions of how the engine "feels". Check the items I mentioned before and let us know what you observe.

-Stefan
by SScandizzo
Sat Jan 06, 2007 4:05 pm
Forum: Stirling and "Hot Air" Engine Forum
Topic: little machine shop walking beam engine
Replies: 7
Views: 6558

Hi Larry, Without any heat applied, if you flick the flywheel either direction, it should spin about a quarter turn or so and then bounce back to its resting position. If the flywheel simply spins without rebounding, there is a reasonable chance that the system is not air tight. Try disconnecting th...
by SScandizzo
Fri Dec 29, 2006 2:25 pm
Forum: Stirling and "Hot Air" Engine Forum
Topic: cylinder ratios
Replies: 14
Views: 33873

Hi Donnie, I haven't tried it myself, though like you I have found several sources that mention it. Perhaps you could design your engine with a replaceable displacer so that you could try different configurations? It's a bit more work to make the cylinder openable, but I have found it a great deal e...
by SScandizzo
Sat Dec 23, 2006 3:00 pm
Forum: Stirling and "Hot Air" Engine Forum
Topic: Home Built Stirling for Remote Power Generation
Replies: 42
Views: 38906

Ah, yes... we're back to the half-buried drum idea. (Still love it!) The only big concern I would have with an outdoor LTD engine is that friction must be maintained at an absolute minimum for these guys to work properly. Keep in mind that low-temp differentials also have very low output for their p...
by SScandizzo
Tue Dec 12, 2006 4:00 pm
Forum: Stirling and "Hot Air" Engine Forum
Topic: cylinder ratios
Replies: 14
Views: 33873

Hi Gary, The proportions I used in my equations came from Roy Darlington's book: Stirling and Hot Air Engines and James Rizzo's Stirling Engine Manual . Their explanation is that the one-third two-third ratio was derived experimentally by Stirling. I believe that it assumes air as the medium. I stan...
by SScandizzo
Mon Dec 11, 2006 11:35 am
Forum: Stirling and "Hot Air" Engine Forum
Topic: Strobe to Measure RPM
Replies: 6
Views: 6802

Good catch, Ben! I thought this at first as well. Turns out that at 60Hz a fluorescent light flashes 120 times. I'm not sure of the electrical explanation, just that that's the way it actually works. Regardless, I built an electronic revolution counter using a tiny magnet as the trigger and a hall s...
by SScandizzo
Fri Dec 08, 2006 5:18 pm
Forum: Stirling and "Hot Air" Engine Forum
Topic: Strobe to Measure RPM
Replies: 6
Views: 6802

Actually, Donnie, there is a VERY easy way to measure RPM. http://www.sherline.com/rpmgage.pdf Basically, its a paper wheel with black and white divisions on it that takes advantage of the fact that fluorescent lights flicker at 60Hz. The page is pretty self-explanatory, and I can tell you from my o...
by SScandizzo
Fri Nov 24, 2006 8:08 pm
Forum: Stirling and "Hot Air" Engine Forum
Topic: Flywheel
Replies: 12
Views: 10449

Hi Donnie, The answer is that it depends on your engine. More specifically, what its power output is and its intended use. Most "hobby" sized engines are going to have a flywheel under 6 inches in diameter and less than a pound in mass. BUT, this varies significantly from case to case. One thing I c...