DjuiinoStar High Performance Low Temperature Stirling Engine

I am a high-school physics teacher, and bought this to demonstrate how a heat engine can perform work. It was pretty easy to set up if you read the directions, and it seems pretty sturdy (obviously it is still a delicate instrument and care must be taken if you let students or children handle it. The unit is very attractive, and the clear cylinder allows the students to see what is going on with the displacer and work piston. Having a separate work piston definitely helps students see that the displacer is just moving air, not doing the work. When it begins to slow down on a cup of hot water, adding ice to the top helped the students see that it is the temperature differential that matters. Then one of my students asked if it would run backwards if we put ice on the bottom! Put some ice cubes on a towel (both for insulation and to reduce the mess), give a bit of time to establish the temperature difference, then give it a gentle nudge and it runs in the opposite direction from before. Leading from this demonstration, I asked my students if they would like to do a bit of mechanical engineering and build their own Stirling engine, and they excitedly said yes! I've got six teams now working on different designs. It will be interesting to see the results, but this demonstration aid definitely got them "rev'd up! For AP Physics students, this is a great entry into the laws of Thermodynamics. I've paired it up with a "Thirsty Bird" which illustrates a heat engine based on thermal expansion.

I am a 71 year old scientist with multiple graduate degrees in chemistry, biochemistry and pharmaceutical chemistry and this is the best toy I have ever received since my first chemistry set and Erector sets when I was 5 yeas old. The engine is beautifully made - it is as much a piece of art as it is a working demonstration of entropy.

Just place on a mug of hot water and give it a spin and you're up and running! Only minor assembly required.

Got it to run 11 HOURS and 19 MINUTES! When I received it, it had some squeaks so I tried the recommended graphite treatment which helped, but it still ran a bit rough. I then used a very tiny bit of Ballistol using a q-tip and it the ran nice and quiet. I was getting 2 - 3 hours using a large mug of boiling water. Then I tried a 1.7 liter thermos bottle and got the 11+ hour run.The thermos has a 1-5/8 inch opening and smooth plastic at the top, which seals good with the bottom plate of the engine.

Great product. Well packaged. And the best guarantee you can get. Mine works great. Now for some advice. I know it's advertised for a coffee cup (hot bottom), but it can also works with cold bottom warm top. I have one of those freezer gel packs you use for sprains and the like, and I set it on one of those. It was churning along at 150 RPM in no time with just normal room temp on top. Then you can take it off the gel pack, and it keeps going for a while. Even better, as it slows down, you can place two fingers on either side of the wheel on top and the heat from your fingers compared to the still cold bottom will keep it running for several minutes more.