Sunnytech Mini Hot Air Stirling Engine Motor Model Educational Toy Kits Electricity HA001

This thing is amazing! First off, it came packaged in 3 boxes. A fairly large box with air packets for cushioning, then there was a smaller box with yet a third smaller box within it! I did notice all Oriental (Chinese per chance?) writing on all of the boxes, but the very small engine was found intact. I was a little concerned by the negative reviews I've read, but I am very pleased with the quality control on this item. There was also a slip of paper written in English with simple instructions inside the box. All the screws were in place, all the rods, linkages were intact, everything was tight and looked ready to go....... and (being a 62 yr. old kid) I simply had to fire it up immediately! I poured a little alcohol in the alcohol lamp, threaded the wick, placed it in position and lit it up. Within half a minute (the directions say 20 secs.) I gave the flywheel a spin and it took off like a champ. If you leave the flame in direct contact with the motor, it keeps gaining RPM until it could vibrate off of the table. I merely moved the lamp away a wee bit and it slowed down to a manageable speed. I, too had a problem with the magnet falling off of the alcohol lamp, so I put a drop of Gorilla glue on it and set the lamp on top and it is quite solid there this morning. I had some trouble with the wick working down inside of the lamp due to vibration. As the wick is made of several strands of string, I thought I could tie a simple knot in it to hold it in place. If I failed, I figured I could replace the string. This simple knot seems to work pretty good as the wick now stays in position better. It did shorten the wick somewhat, but it still seems to work pretty good. I can always replace it with a longer wick. I couldn't help myself, but I ran two full tanks of alcohol through the lamp just watching this thing run. It seems impossible that it could operate, yet it does! Back to the review...... It came with a small foam wrap that had two glass bulbs and two O-rings in it, When I first opened the third box, a very small nut fell onto the table. I couldn't find where one was missing on the engine, so I simply double-nutted it on one of the screws to keep it from getting lost. I assumed that it is also a spare part? Tighten with care as this is a very small nut/screw. The base measures 1-7/8" by 4" and the engine stands about 2" tall overall. It appears to be built pretty good for a toy, the fit and finish being very good on the machined parts. It has only one flywheel (the catalogue description claims "twin flywheels". The base is either stainless or nickel plated steel. The Stamped parts are well made of fairly thick steel (again, these too look stainless) with a brass 1/4" elbow for an engine housing! It looks to have glass cylinders with a metal piston on the hot (top) side and a plastic piston/cylinder on the cold side of the engine. The connecting rods have ingenious linkages to the crankshaft with keepers to hold them in place. The unit came fully assembled, all nuts/screws were tight, and the unit is pleasing to the eye. It seems that Sunny Tech got their quality control straightened out. To me, this is an amazing work of science at a very affordable price. I highly recommend it to anyone with a mechanical aptitude. -------> I'll be quiet now. ;-)

Well built and came with a variety of parts to build little contraptions for the engine

it's about 4Lx2Wx2.5H inches. Well well packed in 3 boxes inside each other with ample foam padding and bubble pack. Although effort was made with a rubber band to prevent the hot cylinder linkage from disconnecting from the flywheel during shipment it did. the printed instructions indicate this as a problem and provide directions for correction. I HIGHLY RECOMMEND that you watch all the available videos (YouTube) before operation. i'm giving this a 4 only because mine only came with 1 alcohol bottle and it's advertised with 2. it did come with the 2 spare hot cylinder glass tubes and o-rings as advertised. in addition, unadvertised, it came with a little plastic fan assembly kit (just to give it some work to do) and a long plastic eye dropper like tube for filling the small alcohol bottle. the wick for the alcohol bottle appears to be nothing more than a piece of cut kite string. i am going to replace mine with an old cotton shoe lace. NOW, on to the good stuff. this is a gorgeous miniature working model!. after reconnecting the disconnected linkage as mentioned above i gave the flywheel a slow 360 turn clockwise observing that all the moving parts moved freely with no apparent binding. then a quick spin of the flywheel to see that it would complete one revolution on its own momentum,it did. then i filled the little alcohol bottle using the provided eye dropper like tube. the alcohol bottle come with a small metal lid with a hole in the middle to insert the wick through. you do NOT need much of the wick exposed on the top for a nice small hot flame. use NOTHING LESS than 91% isopropyl alcohol that you can get at drug store. i intend to use 95% denatured alcohol, that you can get at any paint store, but haven't tried it yet. by now your wick should be thoroughly wet. turn the flywheel manually until the hot piston is all the way back in the cylinder exposing the most empty glass area. this will allow for the maximum volume of air in the cylinder to be heated. carefully light the wick and place the alcohol bottle on the metallic base (the bottle has a small magnet on the bottom to hold it in place) positioning the flame just short of the end of the cylinder tube centered underneath. the instructions say to give it 20 seconds to warm up. i found this insufficient on my model. give it at least 45 to 60 seconds to warm up and then give the flywheel a solid spin clockwise. VAVOOM! i feel fortunate that mine must be very well balanced because it didn't walk across the desk top at all, as many folks have reported. anyway this little thing really whirs away! ALL & ALL i would give this 5 STARS for design, craftsmanship, quality, aesthetics and functionality. if you're a big boy looking for a new toy, go for it! ps: ordered Amazon Prime and arrived in 2 days!

Built far more solid than it appears. We added some washers to reduce vibration which sped up the engine. Great toy, my husband plays with it constantly and his friends and family love playing with it too regardless of age.

Took a month to arrive, but is good quality, and would recommend to others.

bien recu , merci!