Aluminium boat out of one piece - self casted, one big mold...

Discussion in 'Boat Design' started by congoriver, Jun 23, 2010.

  1. Deadeye
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    Deadeye Bender of Nails

    Yup, that's why I agree that the boat isn't appropriate for what the OP wants to do. However, since we are talking about a starting point from which to build, it's best to start with the known values.
    These are boats they can build and already have the materials at hand, it's a suggestion about how to maximize the utility of what's already there to move forward right now.

    As the locals get more produce downstream with less spoilage, their prosperity will increase far more than if an external entity parachutes a solution into them. Eventually, they can buy all the steel barges they want, but for now it's about relieving the pressure of importing foods while local foods go to waste for lack of transport. That will free up more of the economy to do things like....train boatbuilders.

    It's far more effective to help people help themselves than it is to simply help them....

    I started my post with a question, my question stands.
    I'm curious to know why it hasn't worked - I'm assuming it's been tried.

    Okume and mahogany come to mind right away, what's wrong with them ?
  2. Pierre R
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    Pierre R Senior Member

    No one has asked Congo the first question that I would seek the answer to. When you have a situation where people are not destitute and you have a very poor infrastructure, you have a government problem. Sometimes those governments are not real keen on you solving a problem their problems without a way benefit them directly.

    I would answer the question of the openness of the government to really give the green light to the whole charade. Until that is a given, the project is doomed to failure.

    We cannot even clean up an oil spill in the USA without significant government intrusion and blunders. I can only imagine the problems in the Congo if the problem exists in this day and age.
  3. hoytedow
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    hoytedow Carbon Based Life Form

    Good point, Pierre.
  4. mental_boy
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    mental_boy Junior Member

    Wow, so at $300 for a 4mm sheet, steel in the congo is 4 times the price of steel here in California. Of course, to get steel here for 55 cents a pound you need to buy 10,000 lbs or so.

    Anyway, I'm curious to see if we can nail down these design requirements more.

    1.For the Lisala to Kinshasa route, could you estimate just the time spent traveling on the water for both directions? Then we can get the exact route length:

    And then we can estimate the average current and the speed of the boat.

    2. What would be an appropriate amount of cargo to carry and an appropriate number of passengers? 25 tons? 50 tons? Ratio of cargo to passengers?

    3. Types of fuel available and costs.

    4. While we're at it, commonly available engine types, say 50- 100hp+ (just a guess).

  5. pedalingbiped
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    pedalingbiped Junior Member

  6. Pierre R
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    Pierre R Senior Member

    Pontoon boats made out of 55 gallon drums or culverts just don't carry enough weight. You would need about 280 or so 55 gallon drums for a 40 ton load. That is about 800 feet of pontoon.

    I suspect that only a very efficient monohull is likely to deliver the economy of operation needed in small load of under a hundred tons. In all reality I don't see how you can beat $70 per ton with a small diesel powered boat.
  7. Pierre R
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    Pierre R Senior Member

    I did some rough numbers to try to beat the $70 per ton fee. First let's assume that $70 per ton is for a metric ton.

    If we built a boat 70' long (21.3 m), 16' (4.9 m) wide and 10' (3.0 m) and powered it with a single 175 hp diesel we could probably carry 80 metric tons, people cargo, whatever.

    Such a boat could be powered at 6.5 knots burning about 6 gph. Now assume the current averages a knot and three quarters. The trip is 700 nm each way. A round trip would be 232 hours. The fuel would be 1400 gallons. Now assume $4.50 per gallon as a guess. The fuel bill would be $6,300, pay the crew for a month, three persons, say $ 3,000, add on maintenance of $ 1,200 and uninsured I come to $10,500 round trip. Now divide by 160 tons or two 80 tons loads and you come to around $66 per ton if nothing bad goes wrong and I am half way correct on my guesses. This includes no profit or capital costs of course.

    The float'n Village People don't look like ripoffs at this point.
  8. jonr
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    jonr Senior Member

    You should be able to run somewhat slower and could certainly pay the crew less.
  9. Pierre R
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    Pierre R Senior Member

    How much slower with a current? My calculations are at an S/L of 0.8. With 175hp the boat could never reach hull speed. The two lackies I calcuated at $13 per day. The captain at $2,200 a month. How much less?
  10. troy2000
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    troy2000 Senior Member

    That is some people's answer to everything: cut wages.;)
  11. hoytedow
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    hoytedow Carbon Based Life Form

    Better low wages than no wages.
  12. eric le marin
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    eric le marin naval architect

    Your figures are for USA, you forgot that :
    " Then you have to add administration costs, which are around 2000FC per bag (say US$2), so that's another US$20 per ton"

    And the wages are funny too.

    For the steel,the price in Kinshasa depends of the age of your grandmother. Use the price in the US.
  13. liki
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    liki Senior Member

    Just a thought ... Perhaps you could learn from the container-business. You could manufacture many small & cheap, perhaps stackable, dead-simble bathtub-alike barges from GRP, roto-plastic, or other suitable mass production material.

    The locals could order & rent empty barges up-stream, eventually loaded with local goods and have them towed in large rafts.
  14. kerosene
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    kerosene Senior Member

    Suggestions of advanced manufacturing methods echo of no understanding of a not so well doing 3rd world country. Simple thing as getting a barrel of resin might be hellish job with tons of red tape and silly "administrative" fees.

    It really seems that the 2 options are steel and wood. Both are easy to fix with rather basic tools.

    I think wood is likely to be much better option. Getting a portable sawmill is 1st step. In rural philippines a lot of the boards are done "freehanding" with a chainsaw. While its impressive how straight the guys can cut with the saw - a simple sawmil platform that has a chainsaw bolted on can make the cutting way more accurate and much faster too. I was involved in setting one these up in country side in Philippines. Such setup is quite cheap - but will probably not last too long if operated by fools.

    Still as said you need to define the needs and specs 1st. People are not asking how wide the river is to know if its 5km or 30 km, they want to know if there are narrow passages that limit the width.
    Is the current really 10km/h? that would mean over 5 knots needed just to stay static - seems really high. If the floating villages can make it upstream then 10km/h seems impossible.

    From your numbers passengers pay much better than the crops so the people capacity is quite important. Also I would imagine that when there are paying people they will be taken on board even if the boat if "full". Some spare room for safety is needed.

    Where can you get fuel? If here and there maybe you don't want one boat going all the way. but 3 smaller boats doing split distance.

    The basic brief has to be defined better before you can make educated guesses on the designs.

    No ill spirits meant but, it seems like you missed often the point the way you answered to the earlier list of questions. Maybe you need to find the correct person to run the venture very 1st.
    You need a good leader for any kind of project to get anywhere. Someone who has a lot of practical experience and good eye on picking the key people.

  15. congoriver
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    congoriver Junior Member

    I think I'm the correct person. But we'll see.

    I think I might be a good project leader. Perhaps that's why I have a very high success ratio, and perhaps that's why I have attracted several million dollars in funding from some of the world's leading development organisations.

    You don't do that if your projects fail.

    Have you ever done a project? Because when you start advising people who've proven their worth, you must have some credibility to do so.
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