How much Push or Pull do you need ?

Discussion in 'Propulsion' started by Canada Bob, Dec 22, 2011.

  1. Mr Efficiency
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    Mr Efficiency Senior Member

    Does this mean you won't be buying the Patented Plunger Powered Push-Paddle canoe :confused:
     
  2. Canada Bob
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    Canada Bob Junior Member

    Thanks for the above Mr E, appreciated...

    The thing is, I think I have developed a way to push a boat in such a way that there would be little if any pulsating effect, the main reason for that being the frequency of the action. As mentioned previously this is no more than a concept at this point, one that may become little more than a pile of sawdust at the end of the day, but experience has taught me that if you have an idea the worst thing to do is not to follow up on it, and one of the best things to do seek the opinion of others to see if you have a foundation to be working from.

    As for the "push plate" that's not what I envisage, it's simply the "graphic" of the principle. What I was asking was, would a push plate propel a boat, if it would then the method I have in mind of applying that "push" would also work. It was the principle {of pushing a boat} that I was attempting to describe, not how I would apply the push.

    Your time and consideration to this little project of mine is respected and valued in good account.
     
  3. Canada Bob
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    Canada Bob Junior Member

    LOL, aye, well, humour is appreciated ;)

    I will attempt to say more, and to explain why I can't "disclose" all.
     
  4. Canada Bob
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    Canada Bob Junior Member

    I regret that my posts caused you frustration Tom, that wasn't my intent.
    As for exchanging PM's Tom the offer is appreciated, but due to the season etc I haven't had much time to get into exchanging PM's, add to that {with all due respect} at this point I'd prefer and welcome open debate & input.

    The questions aren't meant to be evasive, nor to be obscure, I was simply looking for some input as to what would the "reaction" be if a boat was pushed by a force applied to the water astern of it.

    The example of the "push plate" was intended to graphically describe the principle of the perceived propulsion, not the method that I would actually use to apply the force.

    I wasn't intending to be coy, nor to present questions that couldn't be answered, the problem that I have {other than if this concept would work} is that, if it does work then I would be applying for a Patent for it, but...

    Having worked with Patent Agents since 1978 I am well aware that if I were to describe {in detail} the invention {in a public domain, such as this forum} that would disqualify any attempt to patent the concept, so {having been taught to be cautious} I'm stuck with that restriction, yet...

    Having said that, I am allowed to consider {in public with others} the basic principles, in this case that being, as originally outlined "how much force would be needed to propel a canoe".

    Once I get a ball park on the force that would be required, I would then know if my "engine/propulsion unit" would be able to produce it. After that it's down to the size and shape that this force would take, to best optimize propulsion.

    Hence my questions about the size/shape of a "push plate" and the force that would be needed to start moving the boat {initially at a slow rate}.

    So, back to the initial questions {I'm sure that the answers aren't illusive}...

    Without getting into complex calculations about hull shapes etc, what {approximate} force would I need to apply to a 1000 lb boat {say a basic canoe style} to eventually get it up to 5 knots.

    I don't need anything more than a Ball Park figure, it's simply to see if the force might fall within the ability of the little "engine" that I have in mind.

    The concept of mine is based on two simple principles...

    1: You can't compress water.

    2: For every action there's a reaction, as we have already seen in here ;)

    Once again, I appreciate the feedback, no one is more "frustrated" than I am that I'm not able to reveal the concept in greater detail within a group that would be well able to help me evaluate the potential for this little project.

    Back to that "eureka" moment, I guess that it's reasonable to consider that propellers will become obsolete at some point in time, the question is, what will replace them, and if we are to "think outside the box" what would you imagine could replace them ?

    Canada Bob.
     
  5. Submarine Tom

    Submarine Tom Previous Member

    Thanks for that Bob.

    Propellers are pretty darn good all considered.

    I think (outside the box) that what makes propellers obsolete wont even resemble a propulsion unit. It wont be a sail, or a kite but perhaps something more along the lines of phase change, matter altering, what we might think of now as "magic".

    The merits of the propeller are far reaching and hugely refined. Although most are commercial trade offs, high efficiencies can be had if designed to the exact application. Some approach 90%. Paddle wheels are even pretty decent and may be worth a look if they have enough similarities to your design. If so, check out the herring-bone style of angled entry which reduces slap.

    I know you like to work in theory with formulas and I am more of a hands on kinda guy so I would suggest you take a thrust rated electric motor with a fresh battery (perhaps from your car) and measure your speed through the water in that 1000 pound canoe. I'm going to guess 3 or 4 knots with a 40 pound thrust. If it's still lake water, you could use a GPS, just turn around 180 degrees and do a second run in the opposite direction and average them. FYI my 8000 pound houseboat (25' X 10') moved at 5.0 knots with an 8 Hp 4-stroke outboard (gas) on the back in still airs. How much thrust is that? I have no idea nor have I ever measured the drag at that speed.

    -Tom

    Just Googled up a 1Hp equalling about 22 pounds thrust so my houseboat drag is roughly 175 pounds at 5 knots FWIW...
     
  6. truecougarblue
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    truecougarblue Junior Member

    Probably too much info, hopefully put the thread to bed?

    Edited, apparently not very helpful, sorry.
     
    Last edited: Dec 28, 2011
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  7. DCockey
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    DCockey Senior Member

    Content deleted because content of post I was replying to was deleted.
     
    Last edited: Dec 28, 2011
  8. truecougarblue
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    truecougarblue Junior Member

    Edited, forgive the harsh answer.
     
    Last edited: Dec 28, 2011
  9. DCockey
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    DCockey Senior Member

    Content deleted because content of post I was replying to was deleted.
     
    Last edited: Dec 28, 2011
  10. Mr Efficiency
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    Mr Efficiency Senior Member

    Canada Bob is engaged in an exercise akin to re-inventing the wheel here, I think he just has to go ahead and get it in operation, then decide if it beats the propellor "wheel", which may mean he doesn't die wondering, if nothing else.
     
  11. Canada Bob
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    Canada Bob Junior Member

    Hmmm, looks like I unintentionally started a grass fire in here, I have no appetite to stir controversy, conflict, disrespect or sarcasm at all, others may have appetite for that, I don't, but maybe I innocently primed their pumps.

    Maybe it's appropriate for me to give some indication that I have come up with things before that others thought were a waste of time and energy, and "as above" most of them wanted nothing to do with, until they proved to practical and useful inventions, I guess it's down to a frame of mind, some folks take the easy route and say "it can't be done" others say "why not" and then put their mind to it.

    Maybe a bit of background might indicate that I didn't start this thread off to wind folks up, but rather to gain a bit of insight, other than my own, "two heads" and all that.

    As a lad {an apprentice engineer with De Havilland Aircraft} in the UK one of the first projects I worked on was the design of an arrestor net that would {hopefully} catch aircraft that hadn't been held by the arrestor wires on aircraft carriers, it was an interesting project one that placed me at an early age with folks well able to "think outside of the box", I learned a lot from them.

    Years later I took up golf, but before joining a golf club I decided that it might be a good idea to practice {with my borrowed clubs} in the back garden. It didn't take me long to figure out that I spent more time walking after and looking for the golf balls than I did hitting them, so I bought a sheet of 3/4" mesh fishing net 12ft wide x 8ft tall, this worked well in that I spent less time wandering about retrieving the golf balls.

    The problem was, I wanted to see how accurate my shot was, so as I swung I took my eye off the ball {that don't help} just to see whereabouts the ball hit the net, my game {for what it was then} went worse.

    This left me "wondering" how could I keep my eye on the ball, but still see where the ball had hit the net, to see if I was hitting all over the place, or, if I was consistent to see if I was hitting to the left or the right etc.

    It aint easy trying to catch a ball traveling at almost 300ft/sec rattled into a net stood just 10ft to 15ft away from you, but the quest/challenge wasn't discarded, there had to be a way to do it. Thankfully recalling how we had 10 or more years earlier tried to capture aircraft on the deck of a ship by using a sort of pocketed net I came up with a practice net that was still 12ft x 8ft but consisted of a series of pockets rather than just a flat panel of netting, each pocket was 6" x 6" square, so there'd be 384 individual "pockets" each around 8" deep.

    The idea was that as the ball hit the net it would extend the pocket, and the net itself would absorb the energy of the ball, soon after gravity would take over than the ball would drop down inside a pocket, and be held there until you took it out, you could hit as many balls as you liked into the net, it would catch them all, and hold them all until you took them out.

    This "Catcher Net" caught on real well when folks saw what it did, and how practice became fun using the net. I finished up applying for a Patent in some 26 countries in 1978 I think it was, and shortly after a company took over production {paid me a royalty} and the thing sold around 2,000 nets a month all those years ago.

    It wasn't just used for golf practice either {it was used by Lee Trevino though}, it was also used by Arthur Ashe to practice serving Ace's at the Doral Club in Florida. also used to hockey practice {ice, street and field hockey}, also by the Tokyo Giants for Baseball {pitching} practice, and by Lancashire County Cricket for bowling practice, you could even use it for soccer practice, it would catch and hold any ball sent its way, at speed of well over 100 mph.

    The link below will take you to that original Patent Application.

    http://www.sumobrain.com/patents/wipo/Ball-game-practice-device/WO1980000663.html

    Since then I have learned a lot about Patents, and how to avoid the Patent Agents becoming the main beneficiaries of your inventiveness, but as much as anything experience really has taught me to be cautious, you have to be real careful of what you disclose prior to applying for a Patent, otherwise you loose the IP Rights {Intellectual Property Rights} that become yours immediately you have that "Eureka" moment.

    The odd things is, birds of a feather do tend to flock together {I guess this Forum is proof of that}, and over the years I have come into contact with other inventors, who oddly enough seem to be eccentric enough to invent one thing after another, the inventions aren't always commercially viable, but for the main part they are useful or at least fun {and an exercise for the mind}.

    The eccentricity is that they rarely constrict themselves to a particular field of interest, more often being inventions completely unrelated to one another.

    Since I came up with the Catcher Net {a long time ago now} I have patented a couple of other inventions, this one was a way to burn sawdust pellets in a regular fireplace or regular wood stove rather than needing a dedicated pellet burning stove, if you're interested that on the link below...

    http://www.patents.com/us-5941234.html

    More recently I came up with a cosmetic product that provides a very different way to shave...

    http://www.google.com/patents/about/7354573_Shaving_after_shave_and_skin_con.html?id=LTyoAAAAEBAJ

    A derivative became a Tattoo Aftercare cream {are we diverse enough yet} ?

    http://www.afterinked.com/locations/locations.asp

    http://www.facebook.com/AfterInked?v=feed

    The above cream is now the #1 Tattoo Aftercare product, worldwide.

    Back to this new method of propelling a boat that I have in mind, I hope that after taking into account the inventiveness outlined above it may become evident that my original post in here wasn't a wind up, nor was it any more fanciful than any of the other things that I have come up with. Nor was it to insult anyone's intellect in here, quite the opposite, it was in respect of the intellect and experience in here that I asked folks for their thoughts and feedback.

    What is it that whets the appetite of some folks for belligerence and/or sarcasm ? Maybe it's the only thing they are able to contribute.
     
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  12. Canada Bob
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    Canada Bob Junior Member

    I hope that helps and I genuinely hope you've had a stroke, of genius.
    Thanks.

    That is a rare thing these days.
    Aint it just ;)
     
  13. Canada Bob
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    Canada Bob Junior Member

    Could have responded better...
     
    Last edited: Dec 28, 2011
  14. Canada Bob
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    Canada Bob Junior Member


    pistnbroke how apt is that !!!
     

  15. Canada Bob
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    Canada Bob Junior Member

    Thanks for that Bob.
    Not a problem Tom, seems it's easier to get on the wrong side of folks than to get on the right side of them...

    Propellers are pretty darn good all considered.

    But like anything else they really aren't "here to stay" they will become obsolete.

    I think (outside the box) that what makes propellers obsolete wont even resemble a propulsion unit.
    Agreed...

    It wont be a sail, or a kite but perhaps something more along the lines of phase change, matter altering, what we might think of now as "magic".
    Then again, it may be something we have now but we haven't seen how it could be applied to this task. That's why we often see new inventions and then {amazed at their simplicity} ask why we didn't think of that !

    The merits of the propeller are far reaching and hugely refined. Although most are commercial trade offs, high efficiencies can be had if designed to the exact application. Some approach 90%. Paddle wheels are even pretty decent and may be worth a look if they have enough similarities to your design. If so, check out the herring-bone style of angled entry which reduces slap.
    Understood & appreciated...

    I know you like to work in theory with formulas and I am more of a hands on kinda guy so I would suggest you take a thrust rated electric motor with a fresh battery (perhaps from your car) and measure your speed through the water in that 1000 pound canoe. I'm going to guess 3 or 4 knots with a 40 pound thrust. If it's still lake water, you could use a GPS, just turn around 180 degrees and do a second run in the opposite direction and average them. FYI my 8000 pound houseboat (25' X 10') moved at 5.0 knots with an 8 Hp 4-stroke outboard (gas) on the back in still airs. How much thrust is that? I have no idea nor have I ever measured the drag at that speed.

    I guess that {if you are interested enough Tom} we could exchange a simple NDA then on the understanding of "Confidentiality" I could raise the veil so to speak.
     
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