Interested in tinkering?

Discussion in 'Shop Talk' started by jgbndaudio, Feb 9, 2005.

  1. jgbndaudio

    jgbndaudio Well-Known Member

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    Hello,

    Anyone else in or near orange county, NY?
    I have a lot of mechanical ideas but I do not have all the skills I need to follow through on implementing them. I have the pieces parts and ideas but need a mechanically inclined partner who can at a minimum weld.

    Currently I'm thinking about the following projects:

    A bicycle generator, to help offset my grid electricity use.
    A pretty big solar oven to bake bread to sell at farmers market.
    A mixer that uses a bicycle to mix the dough for above. Don't want to use electricity and want to make large batches.
    A waste oil burner to burn waste vegetable oil to make heat and hot water.

    There's more but that gives you an idea of what I'm talking about.
    Drop me an email if you're interested.
    Scotty
     
  2. desdawg

    desdawg Well-Known Member

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    You should probably go by Orange County Choppers and pick up the stuff they throw around in the yard. You could probably build about anything. :rolleyes: See the Discovery Chanel, American Chopper for details.
     

  3. Highground

    Highground Well-Known Member

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    A bicycle generator, to help offset my grid electricity use.

    This got me to thinking.......
    What about a large fan blade from an industrial fan mounted on the shaft of a heavy duty truck alternator. In a windy location would this generate enough to charge a 12V battery?
    I have seen articles about the bike generator but wonder about using wind.

    Highground
     
  4. Darren

    Darren Still an :censored:

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    Backwoods Home is currently running a serialized article on how to construct a wind driven generator. Part II is in the current month's issue. Forget the truck or car alternators, this is a real healthy/robust design that anyone can build.
     
  5. Dave Halliday

    Dave Halliday Member

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    Washington
    I'm deleting parts of the original question:

    Here are two very good places to start:

    "Could I power my computer or my TV with a bicycle generator?"
    from http://computer.howstuffworks.com/question658.htm
    Please be sure to follow the links from this website as they explain a lot of the ideas.

    The second is a PDF file from Don Lancaster's website (a major pioneer in small computers and music) The file is called Energy Fundamentals
    http://www.tinaja.com/glib/energfun.pdf
    If you are not familiar with PDF files, you will need the free reader from Adobe.

    This one explains the relationships between some of the units of measurement for energy and electricity. He also explains why some of the "talked about" new technologies will remain just being talked about and where we should be focusing our efforts. (not Hydrogen, not Ethanol and especially not Solar Cell unless we are very far from the grid and we really really need electricity.)

    As for the solar oven -- Mother Earth News spun off a group called Journey to Forever and although I do not like where M.E.N. is going these days, the spin off is an excellent archive of good stuff. Here is their article on solar ovens:
    http://journeytoforever.org/sc.html

    The problem here is scaling this technology up to something that will work for you with reproducible temperature and humidity control. My gut reaction is to use a large parabolic array of cheap 12" square mirrors to focus the sun's output onto the outside of the oven (painted black of course). You could use fans recycled from computers (run on 12 volts - bring a car battery to work) to circulate the air inside the oven and use the position of the parabolic array to adjust the temperature.

    Only problem is I don't know if you would get enough heat. We are up near the Canadian border and during the hottest days of summer, we get at best about 900 watts per square meter for about 2-3 hours of the day. The average is more like 200. You would need a huge collecting array to generate enough heat to raise the oven to 300 degrees.

    As for the mixer -- my little Kitchen Aid consumes about 700 watts. It has a bowl size of a few quarts. From the first link (How Stuff Works) we can see that a first-class athlete on a bicycle can sustain about 350 watts for 30 minutes.

    Finally, some really good news:

    The same Mother Earth News spin-off has an excellent design for building an oil burning stove here:
    http://journeytoforever.org/biofuel_library/ethanol_motherearth/me4.html


    I am very sorry to rain on your parade but these numbers are something that people need to have in their heads when planning stuff like this and it's a lot better to spend a few hours learning the concepts and relationships than spending hundreds of hours trying to "guess" why this great idea doesn't work quite yet. The relationships are figured out with simple arithmetic -- no heavy lifting (math) is involved.

    Take care
    Dave
     
  6. jgbndaudio

    jgbndaudio Well-Known Member

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    Location:
    New York

    Hello,

    I want to thank everyone for responding.

    First of all Dave you're not raining on my parade because you don't understand that I already know what is and what is not realistically possible. I've been reading MEN and JTF for a long time! In addition I have already read just about every web page that has anything to do with generating electricity using a bicycle. While you had some good points for a complete novice I've been an audio engineer and electrician for about twenty years and know my way around the electrical side of things pretty well. It's the mechanical I need help with.

    Secondly, I already have a grid tie inverter that takes up to 50 VDC/110 watts and converts it to 120V AC. I have a DC motor that when spun can provide about 40 volts (not peak) I haven't figured the watts yet. I've already tested this setup and it works great. Now I'm looking for someone to help me build a flywheel to even out the stroke and better support for the components. Then I'm looking to use the same bike as a mechanical mixer for making bread dough. I'm not interested in using the electricity the bike creates to power an electric mixer, that would be plain dumb. The loss of power in the conversion to electricity would be significant. Bicycle power is actually best used for mechanical actions such as pumping water or turning a shaft for something such as a food mill. With this idea I need someone who understands gearing a little better than I, and can figure out a way to make a good PTO on the bike itself.

    As far as the solar oven all I know is yesterday in my Sun Oven I managed to get it up to 350 degrees on a mostly sunny day (some clouds). I baked a batch of brownies in about half an hour. Then made curried rice and lentils for dinner after that. For a 30-degree day in Feb in mid-state New York, I’d say that’s doing pretty well. In my opinion the Sun oven is kind of cheap and I'm sure I can build a more efficient design. I have thought I would combine both traditional and parabolic reflector ideas into the unit. I’m talking about something big enough to bake roughly a dozen loaves at a time. I’m planning on building it on a large turntable that may or may not be self-tracking.

    Scotty
     
  7. Dave Halliday

    Dave Halliday Member

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    Location:
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    Hi Scotty!

    Zero problem -- I am new to this forum and did not know where to jump in.

    My chief concern was that Watts is Watts and the human body is only capable of generating about 350 of them on a sustained basis. This is not electrical power generated, this is mechanical power measured by a dynamometer. About one half horsepower.

    As for your DC motor -- how many horsepower is it rated for?
    Have you measured the output voltage with any kind of load (car headlight)?

    For the mechanical aspect, I would use a sheet of plywood braced with 2*4's underneath. Use some steel strap or angle to mount the bicycle -- angle up from the plywood to the bolts that hold the hubs. You could rig additional bracing to support the frame -- this way you could remove the bike with a minimum of fuss and use it for transportation.

    I am assuming that your bike is a multi-speed one and has sprocket gears on both the front crank and the rear wheel. If this is the case, I would run a new bike chain from the rear sprocket back to either your generator or your mixer.

    You want low RPM's at high torque for mixing and high RPM's for generation.
    For mixing, you can have your crank chain on the largest rear sprocket and your take-off chain on the smallest. For generation, reverse.

    You could use Tee-nuts in the plywood to secure the generator and the mixer.


    For the Oven -- I was thinking of a "traditional" bakers oven with a huge thermal mass. A pan of brownies (yummy!) is one thing but to be able to crank out a dozen consistent marketable loaves in one go is another. That is what got me thinking about an oven on a hillside with a large array focused on one wall. Get that puppy up to temp and you are good to go for the rest of the day.

    Instead of the turntable, I would just have a mirror array that tilts to follow the sun. You would need to shift the array to follow the sun's analemma but this would only be needed every couple weeks or so. If you design it right, only tilt is needed.

    Take care and talk with you again.

    Dave