Generator plans?

Discussion in 'Plans' started by Rudy, Mar 20, 2018.

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  1. Mar 20, 2018 #1

    Rudy

    Rudy

    Rudy

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    I have been searching for plans to build an old style generator that will go together with my old style engines like the Stuart 10V and soon the Farm Boy. Preferably without permanent magnets so the drag will be less when just coasting.
    No luck so far.
    Anyone seen anything like it ?

    Rudy
     
  2. Mar 21, 2018 #2

    Rustkolector

    Rustkolector

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    Rudy,
    For small dynamo's the PM Research dynamo kit is ideally sized for the Stuart 10 engines. It is permanent magnet design which causes some cogging, but the rotor magnetic attracting and repulsing action known as cogging cancels out. It does not add any drag to the engine without electrical load present. Also, old Stuart model generators are around, but rare and pricey. Another alternative is to view Tubalcain's Youtube video's of building a model dynamo and be creative. [ame]https://www.youtube.com/watch?v=Zk-nJ6QpTAw[/ame]

    Otherwise you can find DC motors suitable for generator use and disguise them with a vintage looking housing. It is a trial and error approach, and you will usually end up with a PM motor.

    With the Jerry Howell Farm Boy engine, the full-power pulses of a hit & miss design would cause considerable irregular voltage fluctuations when driving a dynamo. Back in the day, very few H&M engines were used for electric lighting for this reason. The addition of a switch mode voltage converter would be required to smooth out the voltage fluctuations.

    Larger scale slow speed alternators or rectified dynamo's are somewhat easier to create, however these would be 4" to 6" diameter and larger than scale for your engine choices. They would definitely be PM and have some cogging, but as I said before, no unloaded drag.
    Jeff
     
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  3. Mar 21, 2018 #3

    Rudy

    Rudy

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    Thanks Jeff. I plan to put on a DC/DC converter to give me some "useful" voltage, so the output level is not an issue. The generator kit from Stuart (and PM maybe) looks pretty ok, but has permanent magnets. I imagine a vintage motor with just windings, no magnets, could be a place to start.
    Rudy
     
  4. Mar 21, 2018 #4

    ShopShoe

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    Historical Diversion for those interested, don't read if you don't care.

    "Back in the Day," when Hit and Miss engines were being used on farms and other remote locations for many tasks, "Electric Plants" consisted of banks of batteries that could be charged by a small gas engine generator or even a windmill. 32-volt (and other) systems were popular in the central U.S. The irregular power from a small engine and generator would not be consistent enough for reliable use, so the engine charged the batteries, which were used for mostly lighting. I have seen other appliances sold for these systems, but they were not that popular and it is rare to find surviving vacuum cleaners, etc. today. My Father used to remember watching 16mm films at church dinners at his remote rural church powered by such a system and he remembers it flickering, slowing down, speeding up, and generally being hard to watch. That would have been in the early 1930s.

    I have occasionally seen the glass cases from those old batteries from time to time and most people do not know what they are.

    It would be an interesting project to model such a system: How would one make miniature plug fuses in miniature ceramic fuse boxes?

    Pardon the diversion,

    --ShopShoe
     
  5. Mar 21, 2018 #5

    Rudy

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    ShopShoe, I think your point is very relevant. After all I'm searching for a vintage looking and feeling solution, so a flickering light bulb would be just fine. I think I will go searching for pictures of vintage power plants and try to make a model resembling something made at that time. Maybe ad a homemade accumulator in a glass tank.
    Rudy
     
  6. Mar 21, 2018 #6

    deverett

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    What sort of size accumulator jar would you be looking at, Rudy? Leclanche cells were (I think) square and if so, something like an HP sauce bottle cut down might be suitable. If not the right size, at least it will give you some food for thought.

    Dave
    The Emerald Isle
     
  7. Mar 21, 2018 #7

    Rudy

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    Dave, yes, I'm thinking like three small square sauce or food oil bottles cut to suitable depth. Will look very Edison like. I will study those Leclanche cells, thanks.
    Rudy
     
  8. Mar 21, 2018 #8

    TonyM

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    How about converting a brushless motor. Or for more authenticity a brushed motor.
     
  9. Mar 21, 2018 #9

    Rudy

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    Tony, a conversion is absolutely the safest route to a working generator, for sure. I'm after something that looks authentic, so covering up a motor can be difficult. Thinking of maybe using the stator windings from a motor of some kind. The rotor will be visible and probably not all that difficult to make.
    I will definitely search for a donor motor that could do the job.
    Looking to achieve something like those in the pics.
    Rudy

    old generator 1.jpg

    old generator 2.jpg

    old generator 3.jpg
     
  10. Mar 22, 2018 #10

    Rustkolector

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    Rudy,
    The alternators you show above are somewhat later era AC alternators than I thought you were looking to model. I have built this type of model alternator using a ceiling fan motor stator and a PM rotor. I know you don't want to use magnets, but there is no other way to feasibly excite a model alternator without using magnets. Otherwise you must have a wound rotor, working slip rings, a separate power supply, and a voltage sensing regulator to control the excitation current and voltage output at the stator leads. Too complex for a working scale model. The 6" dia. alternator in the photo below is an AC alternator capable of a 300-700 RPM operating range. Mine is rated at 100 watts at 600 RPM driven by a 4 cylinder gas engine. .

    The second photo is of a 4" dia. PM alternator made to simulate a DC dynamo. The stator is a rewound 3 phase battery charging alternator stator. It is rated at 36 watts @ 500 RPM and regulated at 12vdc output. It will produce more wattage, but the rating is proper for the engine that drives it.

    The biggest problem I found building direct driven model generators was the difficulty finding small diameter short stack stators with enough poles to get adequate voltage and amperage at a reasonable RPM.
    Jeff

    B-M-alternator-1.jpg

    FB&E-gen-set6.jpg
     
  11. Mar 22, 2018 #11

    Rudy

    Rudy

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    Jeff, actually I was about to ask you about your generator that I saw in your price winning build. Very good-looking machines. Both the plant and the generators. Your approach probably has a much higher chance of success than without permanent magnets. I like both designs. The reason I’m thinking in the direction of the ones in the pics is just the looks. Beautiful machines I can watch for ever. At this stage I’m gathering information, inspiration and I’m learning.
    How/where did you get the housing for your “dynamo”?
    Rudy
     
  12. Mar 22, 2018 #12

    ShopShoe

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  13. Mar 22, 2018 #13

    ShopShoe

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    More information on a generator/battery system:

    After re-reading your earlier response to my post yesterday, I looked this up:

    http://www.delcolight.com/20.html

    I have seen one of these systems preserved. The one I saw had a bank of fuses on the wall near the batteries.

    --ShopShoe
     
  14. Mar 22, 2018 #14

    Rustkolector

    Rustkolector

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    Rudy,
    Regarding the generator housings, you first start with a stator and winding. That is the most important part. Once I had selected the stator and winding, the housing was then fabricated around it. In the case of the dynamo I used slices of heavy wall aluminum tubing screwed together with some epoxy filler and a few cosmetic additions. In the case of later era AC alternator, the housing is more simple. I sandwiched the stator between two pieces of milled flat stock. The rest is cosmetic.
    Jeff

    B&E-generator-1.jpg

    B-M-generator-4.jpg
     
  15. Mar 23, 2018 #15

    Rudy

    Rudy

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    Thanks Jeff. I like your ideas. And the link to DelcoLight from ShopShoe. So sweet. The more I dig into this the more I want to make a model electric plant with all those vintage charming elements.
    Talking about vintage elements. the picture is actually taken out of my office window today. The water tube is wooden and is probably more than 100 years old. And in the building at the end, yes, a very old electric plant, stil active. I have seen it 30 years ago, but now I'm going to ask for a tour with a whole new perspective.
    The buildings used to be an old paper factory, but now hollowed out and converted to a hyper modern office environment.

    2018-03-23 10.01.26.jpg
     

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