Stirlingengineforum.com

Hi All,

I just had my walking beam type engine run for the first time, and man am I pumped!

Thanks to Cartech and Airpot first of all and all the other postings to this board.

Airpot sent me a sample snubber, way under sized, but being impatient I forced it into service as a power piston/cylinder combo. Te opening at the end of the snubber is just 3/16"! I will order the 2KS240 (.945" id) plain cylinder first thing in the morning. My displacer rod guide is way sloppy and vibrates some but it still works. The rpm's are low, I'd say around 80 or less, but I don't care much at this point. I just threw whatever I had together. The flywheel is a 7.25" circular saw blade attached to a VCR hub, and no I'm not gonna saw up any 2X4's with it. The hole for removing the blade is exactly 1 1/8" from center and just slightly over sized. I soldered a "keeper" to the blade and locked the crank throw pin via the set screw. My rod ends and all other moving points are VCR bearings/hubs.

I'm hoping to rebuild the engine shortly with more accurate parts, and more attention to detail. so that it will run with less heat input. Currently I'm having to use a propane torch, with no cooling water hopper. With those, and other, improvements I hope to see a real jump in performance.

Is there a way to post pictures here? If so I'll share the "ugly duckling", or provide a link to my engine if not.

What is really cool was that my wife saw the first run, and had to take back a few negative comments!

Thanks to all who have done the work before me to make this possible, and to the owner-participants of this forum. I can't remember having so much fun with so little effort!

Roger

If anyone wants to see my engine go to:

http://gobblerguns.com/roger/images/uglyduckling01.jpg

or

http://gobblerguns.com/roger/images/uglyduckling02.jpg

A real kick in the pants getting your first one running huh? The usual responce from those around you are that they think you lost your mind. Yes, a very personal experience indeed! Glad to hear I was of some help. The first one is often ugly and while the urge to build a second engine is strong, it's hard not to "rebuild" the first one as well. Ya, all this comes from my own experiences. Congradulations Theropod! P.S. I love the saw blade and the pictures.

Boyd,

I saw the comment about the spammer. Sure glad to see you dumped it. I was trying to help a damned bot! What a steaming pile of organic Stirling fuel. I was at work and didn't have time to give you the go sign ealier today.

I'll be more careful from now on.

I ordered the piston/cylinder from airpot. The 1" id set 3.5" long with shipping is $41.88! Yeeeeooooow! Oh well, good stuff ain't cheap and cheap stuff ain't good.

Roger/ aka theropod ( a 3 toed meat eating dinosaur ) (I'm an ex natural history museum director)
aka RogerAS over on fieldlines.com
So human it's sickening.

Hi Rodger,
There is really no way to have known they were spammers. I can look at the more detailed profiles and see it.

Sorry they get through!

Congradulations on the "first run" sure is magic to watch, isn't it! That is why I offer the plans for free on the main website. I love to hear about the "first run". It's great!

Darn thing just shouldn't run, should it?

Darryl Boyd

Hey all,

Well, I took my little ugly duckling apart and did some fine tuning.

I discovered that my displacer piston had overheated, not to failure but near. I'm sure this was a result of early run attempts with my conduit power cylinder, a failure for sure. I repaired that and made a new gland/bushing for the displacer rod.

I found 2 rod guides from a dead dvd player that had .125 id's. These are hard steel about .5" od with about .375 length. I cut a 1.5" hunk of copper tube and solderd both these to the tube with a brazing rod blank alinging the pair. I made a new displacer head from thin steel and soldered the gland to this head. I made the head as close to the od of the displacer as I could. I used Mothers wheel/metal polish to give the brazing rod a work over until smooth as glass. One drop of breakfree on the rod.

I also moved the displacer more directly under the walking beam end pivot point and constructed a new lifting eye/rod. I also took more time to get everything square and straight.

I still haven't fitted a water hopper/radiator, or heat box.

The engine starts easier and runs with lower heat than before. I saw some rpm gain but not a big jump, but the revs seem more uniform and I see less stalling. Before I was seeing about 80 rpm with some real heat and now I guess about 100 with about a third less heat. The engine heats up faster than when the aluminum head was on the displacer, but I hope to solder a set of copper strips on to the head and displacer sides. This may mean a multipart water box. May be more than I can do.

I now take time to hand crank my engine after it is shut down ot avoid "parking" the displacer next to the hot end. In about 5 minutes it's cool enough to let it cool down on its own. When I can get someone really good to braze me up a light displacer I think this cool down procedure can be avoided then.

I plan on fitting the correct id power cylinder/piston later this week. The current one is so small it's a wonder my engine turns on its own! It's just barely over half size id. I hope to get this engine to run on ice water and a big candle for a couple hours. If I can do this I then want to try upscaling by maybe a factor of 3.