A solenoid engine?

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May 22, 2014
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Hi Guys,

I thought that you might enjoy a chuckle today so I am posting a couple of pictures of my latest project. For some time now I have wanted to build a solenoid engine. I have watch several you tube videos and have always thought "how hard can it be?". While helping a friend clean out his basement (he is moving out of state and downsizing) we found several small solenoids of unknown origin, so I thought "now is the time". Anyway, I built a simple solenoid engine. It is my own design, which probable explains why it doesn't work worth a damn.

As with any project, I began by going to my "stock room", which is a fancy name for the pile of junk in the corner of my shop. After digging through the empty beer cans, candy bar wrappers, and dead mice, I found some odds and ends that I thought might work. Yeah, I know, I need to buy some stock.

The crank case" is a scrap of hex aluminum that I bored for a brass bushing. The crank shaft is a piece of 1/4 inch drill rod. The flywheel came from a broken "reel to reel" tape recorder that someone left on the curb and somehow found its way into my shop. (No, I don't have a clue as to how that happened.)

The "beam" is a sand casting I made a couple of years ago out of scrap aluminum. In fact I think it was mostly made from squashed beer cans I picked up along the road. The machine work on the beam is awful for a couple of reasons. First of all, it is very soft aluminum and hard for me to get a good finish, but mostly it is because I am a lousy machinist. Yeah, I know, I need to practice grinding lathe bits.

I had originally thought that I would need to design a governor to prevent the engine from over speeding and self destructing. Boy was I wrong. The danged thing runs, but just barely. I would rate the power output at 1/4 flea power am not sure it is even that powerful. Of course I really do not know just how powerful a flea is.

I guess I posted this to give you experienced machinists a laugh and to encourage the rest of us beginners. I know that I always enjoyed seeing projects that were even worse than the stuff I built (although they are few indeed). Anyway, it kept me off the streets and out of the bars for many hours and I had fun. It will probably now go on the shelve with the rest of my machining disasters, where it will remain until the kids throw it out when they move me to a nursing home.

Keep smiling guys and keep those chips flying. Thanks for reading.

Sol 4.jpg
Sol 2.jpg
Congratulations Dave. We all need something to aspire to these days.

wa8dof, I like the way you described the story, can see it in my mind, I think that a lot of have the same shop as you described, I have a small one that is A/C and so neat and clean, spend more time cleaning than machining, that is why I go to the big shop most often, I really like the engine, I have not make on because of fear of failure, really dont understand how it make the revolutions, I do understand how a solenide works, when I repairs Mowers if I know the customer really can't afford much expense I will take them apart and repair them, might try one someday, do you have a video of it, how do you time it, thanks, Joe​

Nice. I always wanted to build a radial solenoid engine myself. But I never found the time to go so. I have too many hobbies already and never enough time.
A more substantial flywheel would probably see it running better. The solenoid is like a single acting steam engine so you need some stored energy in the flywheel to bring it back round the second half of the rotation

Also if you make the contact strip so it can slide in and out that will allow some adjustment of the time the solenoid's "power stroke" lasts which should allow you to adjust running speed.

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