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Please help a wanabe writer

  1. May 29, 2005 #1
    My first book has made it all the way to the publisher's desk, where I'm told it will sit until I have a second. The first was a bit of cliff-hanger. I'm working very hard on the second and hope to have it finished by the end of the summer. Actually, I hope to have it done in two weeks, but it will take all summer for my wife to fix it. (If you can't write, but discover a need to write a book, I suggest you marry an English teacher.)

    The books are sci-fi and the story line is about a section of a maximum-security prison that marooned on an Earth-kike planet stuck in the stone age. My creative prisoners are now building a boat to make contact with the natives. I am thinking about creating a windmill devise to power a propeller. I'm also still trying to design the ship. (it needs to be large enough to carry 100+ on a 2000 mile voyage.) Sail will provide the main propulsion, but I thought about using a windmill for special work like very narrow channels, or to maintain headway in a storm.

    Now for the question, given steel, wood and welding supplies, how would you construct a such a windmill, and more important a propeller? I need to add they have a parking lot full of cars, but almost no fuel.
  2. jcsd
  3. May 29, 2005 #2
    this windmill store power in batteries?? to be used when navigating narrow channels.??
  4. May 29, 2005 #3


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    This is perhaps prosaic of me, but a long-boat propelled by oars&sails (like a Viking ship) would be a lot more efficient.
  5. May 29, 2005 #4
    i agree, windmills would just be too complicated and would have a million variables to go wrong, especially in a storm! Sails, two, three masted, depends what you want, and maybe oars or a man-powered fishtail. (make sure to get the sailing right, as im a sailor, and i dont want to read shabby sailing! *wink*) by the way, it sounds pretty interesting, so whats the name of the book, so i can look out for it?
  6. May 29, 2005 #5
    Let me backtrack a little.

    The current working title is "Cliquing on Time." Based on what the two editors who've recommended it for publication have told me, it will probably be changed should the publisher decide to buy it.

    I read a few more of the answers on other threads, and I'm blown away by the technical competence here. I found this site through google because of a thread of someone trying to use a windmill for a land vehicle. I am trying to limit the sci-fi to how they were accidentally sent a different planet. I'd like everything else to be science, or engineering. I believe that humans are almost endlessly creative, but I'm not. Thus, I've used places like this to find out if something is possible, and to get tiny thumbnails about how to do it. I've gotten help in other places on many odd topics... like how to make a windmill.

    I agree that building a windmill from scratch would be impossible. But, when I was a senior in high school, my parents bought a ranch... Truly "Green Acres," but that's another story. :smile: The only source of water was a windmill and a cistern. I was always impressed with how simple that Aeromoter windmill was. We took it apart once to grease and repack the bearings.

    My creative convicts only need to pull a drive shaft and rear end from one of the cars to have the "motor" part of a windmill. I think they'll be using one of the tall steel light polls for a mast. One of the inmates is a former nuclear power plant welder, and he has plenty of supplies. They also have steel from the roofs, metal buildings and security doors. What they don't have is any sort of press, or high temp furnace. Part of the reason to build the ship is to get coal so they can work metals beyond welding.

    They can have plans (via their computers and text books) for any sort of design they need to build, but they don't necessarily understand what they are looking at.

    One of the things I don't know --- hence they don't know is just how much energy would be provided by a the type of vanes they could produce. I don't know how much would be lost in transmission and how efficient a propeller they could produce. I had originally thought of having them build a Knarr (Viking merchant ship) but a yachting form suggested I consider something with an outrigger for safety. (I had hoped to use a canting keel for extra speed but it looks like that would be beyond them technically.) I'm trying to understand advice about design and ballast and the strength of wood versus ripping up a whole building to make the hull out of steel.

    The problem is that all I know about propeller design and windmill vane design is that small difference create large changes in efficiency.

    Bottom line, given the welder's skill, could he make an efficient windmill vane and a good propeller. If he did so, would it produce enough power to make a difference. I.E. given a 20 knot wind how fast would a 120' Viking long boat be able to head directly into the wind? If that doesn't work, I guess I'll just have to figure another way to keep them from being blown on to the rocky coast.

    I do thank you for your advice, I do understand just how off the wall this sort of question is.
  7. May 29, 2005 #6
    Are you sure this is fiction ??
    kidding.. sort of... :bugeye:
    for the propeller/s you could bend the radiator fan blades of some of the older cars..
    how detailed do you have to get.??
  8. May 29, 2005 #7
    Hmmm, have you thought of a catamaran type boat..
    ps i was typing when you posted ..which is unusual for this site..
  9. May 29, 2005 #8
    since it was fiction i did'nt think it had to actually work .. so skip the car radiator idea..ok , he has a welder , so they could bend and weld sheet steel together building up the hub with layers till it looked like a real prop..
    question are these prisoners willing to work for their freedom , if so how about hooking each one up to a station where THEY power the ship , ala muscle power..when needed?
  10. May 29, 2005 #9
    Boat ideas

    A lot. That is one reason ships use sails. I would expect that a windmill powering a driveshaft on a boat would not work at all, as opposed to working merely with low efficiency. If it does work at all, it will only be once in a long while when a strong gust comes up -- say, in the 30 mph range. So the boat would run maybe for half a minute every half hour or so, if the characters are lucky.

    Another reason boats use sails is that sailboats can sail almost straight into the wind. If you do that with a windmill-driven boat, you will essentially be manufacturing energy from nothing.

    The characters are going to need a strong impetus for pursuing such a backwards propulsion concept as a windmill-driven boat.

    If you want a water craft that is bizarrely unique, perhaps it could be an amphibious sailboat. Sail up to a beach and keep on sailing, riding on the boat's car-wheels.

    If you have cars and no fabric, perhaps metal sails could be made from the car bodies. Back in the 1980's, Japan produced a sailboat with (motorized, electronically-trimmable) metal sails. If you want to have the characters scavenge fiber material to make sails, the car seats might be good for fabric. Also, cars have carpeting and headliners (fabric on the undersides of car roofs).

    A car's rack-and-pinion steering system might be usable as part of a steering system for a boat. The gearing should be changed, however, to a much more shallow steering ratio (you should make it so the wheel goes around perhaps dozens of times between the locks, as opposed to just a few times -- this makes it easier to steer a heavy vehicle like a boat).

    Another idea would be to skip the windpower idea altogether and have the characters make alcohol or biodiesel to power an engine with. (If they have access to any kind of surplus food-carbohydrates, they can make alcohol -- unless there is no yeast in the air on that planet.) They could also modify their car engines to run on wood-powered steam. And finally there is also a way to run engines directly off of the fumes from gasified wood, but that might be too complicated for your prisoners to figure out.
  11. May 29, 2005 #10
    Great Idea...

    I'm not sure why you said to skip the radiator fan idea in a later post. If nothing else it gives them a template to go from. I'm using plastic fan blades from air fans to generate trickle charges for UPS systems in the unit now, but I thought those would be too small. I'm sure they'd be able to pull a radiator fan to use as a propeller. One doesn't have to get detailed, but I wouldn't want someone who knows something about radiator fans to scoff.

    These men and women have been free for a year... ever since they landed, but they can see their standard of living taking a nose dive soon.
    Last edited: May 29, 2005
  12. May 29, 2005 #11
    I'm not sure I understand...

    I know that someone build some large tankers or cargo ships a few years ago that had windmill assisted power. One's windmill looked like an old fashion kid's toy, the other like the windmills you see on wind farms. The idea on a ship is that the windmill rotates so that it always faces the wind, so the direction of the wind doesn't matter. I know watching our old windmill that even in a mild breeze it could rev up to, what seemed, several hundred RPM. All it powered was a sucker pump but when the wind was up it could fill that whole cistern in no time at all. I just have no idea what the horsepower of the thing was.

    One of the problems I created for myself in the first book is that they are located on a peninsula with a huge tide. Think about something twice as high as the Bay of Fundy. That bay is only a couple of miles wide in several place at low tide. Given a good hull and keel, you can sail close to the wind, but trying to tack on in a narrow bay is murder. Toss in those tides... I had thought about letting them ride the tide out, beach and wait for the next tide, but that's tough too. I figured if a modern

    I hadn't thought about that, I just hate to tear up the cars... I hate the Mad Max view of the thing... still.

    Great idea, I had thought of using an old fahion tiller, but this is much better.

    They've set up a still, a very controversial project since alcohol and drugs are a major reason most folks are in prison. On yeast, I had no idea how hard it is to make yeast. Part of what I'm trying to do is to illustrate just how many common things we take for granted.
    Last edited: May 29, 2005
  13. May 29, 2005 #12
    I don't understand why they would want to use a windmill at all. A sail seems much simpler and more effective.

    The force that moves the ship forward comes from resistance to the air. A sail catches the air and this moves the boat forward. A windmill turns and much of the air passes by it. The purpose of a windmill is to create energy for some other purpose. The prisoners would be much better off sticking that propeller in the water where it would have much more resistance and be more effective. They could create some mechanism to rotate the propeller for forward motion, and turn the propeller like a rudder for steering.

    keels are nice because they help guide a boat. They are streamlined through the water and pushed less sideways by the wind. It is not necessary to have a single hull keel. A double hull is much simpler to construct and more of the boat is out of the water. This kind of boat has to displace less water and is faster and also more stable. Double hulled boats were used by uncivilized tribes for millenia. A boat doesn't even need a keel, but it would be difficult to keep it on course. Hmm, might be prone to overturning in large waves too.

    A 2000mile trip is a long trip. I think water would be their biggest problem. Some method of desalinization might be necessary. The windmill idea might be useful here. IIRC there is a method using a flywheel and a thin stream of water that is evaporated. Check that out before using it. But any windmill used on a ship with a sail is inneficient. They are counter-productive because they are using the same source of energy.
  14. May 29, 2005 #13
    i dissagree..think about it, some wind turbines like www.otherpower.com have 17 foot spans . three or four of these babies on a hundred foot ship might be able to power it in every direction but directly into the wind..
    i am assuming these wind turbines in your story are geared , like a differential of a car, with the driveshaft entry point connected to the turbine , and the driven part connected to a shaft down to another differential driving the propeller?
  15. May 29, 2005 #14
  16. May 29, 2005 #15
    I can do a 17' span

    The problem is what to do with the windmill vanes when the ship is under sail??? I had thought about collapsing them to a single vane and lashing that to the mast. That would take some pretty good engineering and manufacturing, so...

    I'd never thought of using more than one, and then only for special situations. Thanks for the link, but why do you think you couldn't sail directly into the wind? Since the blades rotate 360 degrees, and they always face directly into the wind, I don't see why sailing into the wind would make any difference.
  17. May 29, 2005 #16
    I'm planning on using the differential from a car or two to make it work... True confession, I know those things work, but I just take my car to a mechanic and say, "fix it." A fellow said I could use one to do this so I'm taking his word. He also suggested that I use the rear end of a car to make paddle wheels instead of a propeller. That remains a final option, but paddle wheels are so inefficient
  18. May 29, 2005 #17
  19. May 29, 2005 #18
    I am not sure that would be possible ..
    i dont think any sailing ship ever sails directly into the wind anyway ..you can tac close to it but never directly into it..
  20. May 30, 2005 #19
    Those windmill turbines create electricity, not a whole lot of forward momentum. Although you could possibly use a windmill to create electricity for any number of purposes. An important one might be desalinization. Sails are the way to go. Sails and windmills both used for propulsion are about useless.

    Instead of rowing, having some sort of a pulley system attached to a propellor in the water would be a good way to propel the ship in addition to sails. Doesn't seem to solve any problems and requires a lot more mechanical parts.

    Sailing directly into the wind would not work. The force of the wind is acting in the opposite direction of the ship. If the ship wants to move in that direction then it needs to provide the momentum to do so from another source of energy. Propellors or oars.
    Last edited: May 30, 2005
  21. May 30, 2005 #20
    On a long voyage like this one you might be interested in Hadley cells. Depending on the angle of the planet to the sun certain weather patterns form. I think there are 6 Hadley cells seperated by latitude.
    Here's a picture. http://www.newmediastudio.org/DataD...r/Easterly_Waves/Trade_Winds/Trade_Winds.html

    Some of these regions get more rain than others and have different trade winds. Merchant ships from the Brazils would often go way out of their way to the north to catch the westerlies to head for Europe. A wind is named after the direction it is blowing from.

    The regions between these cells have unusual patterns too. The doldrums are at the equator. The heat causes the air to rise and there is little wind. The direct rays of the sun evaporate a lot of water which cools in the atmosphere. This area has a lot of rain.

    But if you go about 30 degrees latitide north or south then you reach the division of the westerlies and the northeast trade winds. This area is called the horse latitude. It gets very little rain and is the area in the world where many of the deserts in the world are located. It is called the horse latitudes because when sailors ran out of water, the horses would be the first thing that died. I guess sailors would rather save the water for themselves and eat the horses.
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