Sunnytech Hot Air Stirling Engine Motor Model Imagination Development Educational Toy Electricity Generator Colorful LED SC (SC02M)

This is a very impressive machine, with superb craftsmanship and flawless mechanical operation. It is a very attractive display item that I plan to keep on my desk at work, with a supply of fuel and a lighter handy to demonstrate to curious passers-by. My fellow engineer coworkers have also been very impressed with it. It runs surprisingly fast, and is not overly loud, but does make some noise. I am so impressed with its good qualities that I did not deduct a star for the failings of the instructions that came with it. I'll never understand why Chinese companies do not take the simple extra step to have someone who has English as a first language proof-read and clarify the almost universally poor English translations that ship with their products. The instructions that come with this are quite typical of that problem. For example: "Heating 20 seconds, and then began to gently turn the flywheel, (follow the starting direction shown in the figure) until the flywheel can since Dynamic operation so far." Yes, most will be able to figure out what that means, but why not state it in proper English? I'll note that the instructions cover both a Stirling engine and a steam engine. Paper is cheap, why not have separate instructions for each model? And the instructions for the Stirling engine include a figure of a different type of engine than this, leaving me wondering initially if I received the wrong instructions. The model comes with several loose parts, some of which are spare parts, like and extra of each glass cylinder and generator drive belt, which is nice But there is no list of parts with a description, including those needed for operation. Again, it was easy enough to figure out, despite no instructions. But should either of the cylinders need replacing, there are no instructions for how to do this. There is an LED light that also came loose. This is a very cool, color-changing LED that demonstrates that the engine converts heat into usable electricity. Why it is not assembled to the model as delivered, nor even mentioned anywhere in the instructions is a mystery to me. It may also be a mystery to anyone who is not mechanically (or electrically) inclined that you have to spread the LED wires apart and bend the ends so they can fit into the holes in the terminals on the outside of the generator. The alcohol lamp had 3 parts, the glass bottle, wick, and lid. The lid is not threaded and just sits on top of the bottle, so be careful not to knock the bottle over while lit, or you'll have a little Molotov cocktail on your hands. When feeding the wick through the hole in the lid, some instruction as to how far the wick should extend would have been nice. I found that about 1/16" is sufficient, and more extension to give a larger flame did not seem to make the engine run any faster. So far, I've transported it back and forth to work a couple times and put a piece of plastic wrap over the wick and wound a rubber band around the bottle neck to seal it. A bottle with a seal-able lid would be a nice improvement. But I suppose the alcohol is cheap enough that you could just dump out any unused fuel if moving it. As is, all the alcohol in the bottle will evaporate rather quickly with the wick exposed to the air. (Here's a tip for filling the bottle from a can of alcohol without spilling more than goes in the bottle: dip a straw down into the can of alcohol, seal the top of the straw with a finger, then put the straw into the bottle and release your finger. Repeat until bottle is full.) Despite the above nits, I think this is a very cool "toy", especially being a mechanical engineer with a deeper understanding of how it works, and am very happy I bought it. But I don't think you need to be an engineer to enjoy this. I thought the price was a little steep, but feel better about the price after seeing the high quality design, workmanship, and materials used. Oh, since I plan to keep it on display at work, I am concerned about dust collecting and possibly gumming up the linkages and power cylinder that is open to air, so I bought a mini-football helmet display case that it perfectly fits in...see the picture. The case is a "Ballqube Mini Football/Helmet Display Box".

This is a delightful little engine. I'm amazed by the precision of the craftsmanship and the reliability at this price point. It comes fully assembled, works flawlessly every time, and is very fun to watch and tinker with. If I could improve anything about it, it would be: 1. A heavier base, or some sort of counterbalance: The engine does vibrate at high speed and will occasionally try to walk off my desk. The base, and the engine itself are already quite heavy, so I think the right solution would be some sort of counterbalance to eliminate the vibration. But simpler solution might be to add some balast. 2. Power connectors for the little generator: I've enjoyed powering small items with the generator. LEDs, a little heating coil, some motors, etc. It would be nice if this came with terminals and a switch for connecting various items. Clearly this is something you can add on your own, but it would be a nice addition. Overall it's been wonderful fun. I think the electrical power output tops out somewhere in the 2 watt range, which is enough to do some nice demonstrations. And it looks beautiful sitting on a desk or shelf when not in use. Overall I'd highly recommend it to someone looking for a fun, easy Sterling engine.

Overall impression: I was very impressed with the overall quality and "fit and finish" of this model. There is very little I can find to complain about in this regard. Despite some of the minor negatives I'll discuss in a moment, my overall impression is very positive and I would not hesitate to recommend this model to anyone who has an interest in these things. The asking price is a bit on the high side, but given the niche market this appeals to, along with the high quality and solid construction of the unit makes me think that I got a fair deal for my money. Some details: I found all of the manufacturer's claims in the product description to be accurate. It comes equipped with everything shown in the pictures. Packaging was quite adequate for any form of shipment. The main engine was securely wrapped in bubble-wrap, and the spare parts were separately foam-wrapped. Everything was placed in a small medium-weight cardboard box, which was then in turn shipped in a larger Amazon heavy cardboard box with extra protective packing. One of the features of this product that I appreciated the most was the heavy, solid, brushed-metal base that the engine is mounted on. At least 2/3 of the total ~1Kg weight of this engine is in the base. Unfortunately, even this heavy base is not enough to prevent the engine from "walking" across a smooth flat surface when it's running, even with the (included) rubber "feet" on the base. Unloaded, this engine flywheel runs around 1800 RPM when powered with alcohol fuel. The mfr. recommends 95% ethanol, but I did not have any on hand so I used 91% isopropyl alcohol, which works just fine. I would not recommend using anything with a <90% alcohol content (such as common 70% "rubbing alcohol"). The tricolor flashing LED supplied (which you hook up to the attached generator) looks cool when the engine is running, but given its dynamic nature, it places a constantly varying load on the generator, which can result in the engine speeding up or slowing down as the LED runs through its display pattern. The generator outputs a bit over 6V unloaded (6.2V is what I measured). I've not yet had a chance to test/measure the generator output operating under a constant-current load (the included LED is definitely NOT a constant current load). Some (minor) negatives - things that could be improved. Note that I did not regard any these issues serious enough to detract from my overall high rating. The provided fuel bottle and cap/wick arrangement is something of a safety hazard. The cap does not screw on or sit on the bottle mouth securely, which means that if the bottle is tipped or jarred hard enough during operation, fuel (alcohol) could escape from it. The fuel bottle does not fit securely in the indentation for it on the engine base, so it is free to rattle around as the engine operates. Having said this, the fueling arrangement is 'safe enough' if it is supervised during operation. Adding a simple (heat resistant) silicone rubber O-ring around the metal wick cap so it would sit in the bottle mouth with a liquid-tight seal would make this a lot safer. A smaller diameter holder (on the engine base) for the fuel bottle, with more sharply beveled sides, should be used so the fuel bottle has less freedom to move around during operation. The operating instructions that come with the engine are poorly written, badly translated, and do not provide any significant detail on engine construction or maintenance (e.g. how to replace a broken cylinder, or remove it for cleaning). I did not find any instructions or contact info for ordering replacement/repair parts. A more detailed manual, showing a "blow up" diagram of all the engine's parts, along with care and maintenance instructions, which has been properly proofed and translated would have been appreciated, esp. since this is the sort of "toy" that someone who is mechanically-minded (and thus have an appreciation for design details) is going to have an interest in. I would have also appreciated some electrical specs on the attached generator - not the whole datasheet, just some basic details such as rated output voltage and current when used with this powerplant. I found one _very_ minor "fit and finish" flaw after a close examination of the entire engine - the pilot hole in the flywheel, where the setscrew that secures the flywheel to the drive shaft is inserted, was drilled a bit unevenly - it is not perfectly circular on my model. However, this very minor flaw does not adversely affect the operation of the engine or appear to have any notable effect on the flywheel balance.

The engine came well packaged and full assembled. All I had to do was some minor setup, put alchohal in the vial, wick it up to the top, light it... wait a few seconds... then flick the wheel and off it went. Moving like a sewing machine motor, fast and smooth. Good fun for the curious among us, and a nice conversation piece if you have like minded friend and associates.

This is a very well made item. I am very happy with the detail, material, finish and overall look. It worked as expected right out of the box. The engine revved up and lit up the led fine. The next time I used it the rpms did not seem as high and when I tried the led the rpms dropped so low that the engine stopped and the led never even started to glow. After checking all connections, fuel (denatured alcohol), I tried again with no luck. It seems that the generator is not operating under the load of the led. Do you have any solution for this? As per directions in the box I sent an e-mail to Sunny and have not heard back from him.

I am fascinated with Stirling engines and bought one of the low-temp coffee cup ones that I enjoyed for a little while before wanting more. I saw a couple of others but figured I'd get this one due to aesthetics and it was very well-rated. Build Quality I did not expect it to be as well-built as it is. It is very hefty and looks and feels expensive. The amount of compression felt as I turned the flywheel told me I was in for a treat in terms of power compared to the coffee cup one. It is fully assembled other than stringing the wick into the fuel chamber and mounting the LED. The wick can be a little fiddly but no issue once done as long as you don't pull on it. The LED (a spare is provided) is super simple to install...just put the ends through the provided terminals of the little generator, bend and you're done. Up and Running I initially started with 70% isopropyl alcohol but that sucks so I got some 90% and got up and running. It takes about 30 seconds before you can get it to spinning on it's own but once it gets going, it is quite powerful for it's size and fuel source, The LED light is quite bright once it gets going and flashes and changes color to give the unit a bit of extra flare but I ended up removing it for something more useful and interesting to me (see Modifications). I've not let mine run much more than 5 minutes but I can usually run it three times before I need to add more alcohol so I would guess 15 minutes on a tank. Modifications While the LED is okay, I wanted to measure the performance so I removed the LED and bought a small 2-wire voltmeter, cut the wires just short enough that they would support the weight of the voltmeter while remaining adjustable and soldered the ends to the generator terminals to give it rigidity and have a nice presentation. Display does not come on until 2.7-2.8v but it only takes a few seconds for it to get to that once it is running on its own. Typically my motor will generate 4.5-4.8v on a run but every now and then when the conditions are right I get over 5v with my current record being 5.35 volts. Love it. Concerns It has run flawlessly so far but I do fear that if it does break down, it may not be easy to repair as there are only a few spare parts included. Only other issue is that on many surfaces (glass and sealed stone seem best) it will start to move once it really gets to going and potentially could walk off the table if you walk away. This was a splurge of a purchase at the price I paid but I am loving it.

I love this model, I use it to show multiple mechanical processes to my friends and nerd out when they come over. It is also very entertaining, and is capable of running multiple electronic devices and comparing different voltage signals. I do have one grape with the rubbing alcohol wick; whether it’s some issue with capillary action or the quality of the wicked itself, after a few uses, I have a very hard time reloading the sucker and keeping it at a decent distance from the piston bulb. Other than getting around this issue with an alternative solution to burn rubbing alcohol, this model is the best one I’ve seen!

First of all, this Sterling engine arrived in a very short time (about a week) after it was ordered, which was a pleasant surprise. It was well packed and arrived in perfect condition. My eyes lit up, when I unpacked it, I would call this engine, a work of art. It took me about ten days (of some difficulty to find time, to locate the 99% alcohol) fuel that is recommended for this engine. To save a lot of people, alot of time, Home Depot stock this fuel, for under $6,00 that will last me for years. I was so impressed with te looks and quality of this macine, that even before locating the fuel, I ordered the 4 cylinder engine. I used an eyedropper to fuel it and it started right up and runs perfectly. I did have a problem with the generator not functioning, however Amazon gave this problem their immediate attention. I have cmplete confidence in ordering anything from Amazon, a company I trust. I'm certain I'll be as satisfied with the 4 cylinder Stering engine, as I am with this (SC02M) model. It's my desire to order the entire series of these minature Sterling engines, for display in my livingroom, as conversation pieces that I can run, when requested to do so. Irv Gendel

Good delivery

As always it arrived fast, but the box was quite damaged/partially crushed...😮😯 But the contents were so well packaged/protected that there was no damage !😁👍 The Stirling engine is very well made and sturdy, (only very light lubrication with sewing machine oil on the crank bearings and main shaft was done before operating) it has a sort of art deco industrial/medical design and is very cool to look at !😏☺ It works very well ! The only thing is that the hot / expansion glass cylinder that sits above the flame can get blackened after a while and makes it hard to see the piston inside of it... (the cleaner the fuel [ 91% Isopropyl Alcohol is excellent ] and flame is, it will not soot up) Lights up the led nicely! Nice to have the spare parts too! I might try to light up both leds at once to see how much it will affect the performance... It would be awesome to have better and more detailed instructions on operation/maintaning and lubrication of the engine though! 😯😒 All considered it is an excellent gadget and a very cool to watch and a fun learning device !!! Highly recommended !👍👌😀

動いた

The item came packaged very well, and included spare parts, which is very appreciated. It arrived sooner than expected. The engine is so fabulous. I love everything about it. As a previous reviewer mentioned, it is extremely well made and beautiful.

Very sturdy device. Lots of fun to see in action.