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

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

  1. Chris Ostlind

    Chris Ostlind Previous Member

    Actually, no, Richard... I prefer to not contradict. It's just that you seem to like to make broad sweeping generalizations for everything you grace with your presence and a good number of them turn out to be untrue.

    You claimed he said that it can't be done and nowhere in his letter does he say that it can't be done. He simply states that it would take some fairly large bits of equipment and that it's difficult.

    I have seen fairly large bits of equipment in the jungle with people who have extraordinary knowledge operating same. I documented a build of a huge dam in the most remote part of South America and if you don't think that a 5 story apartment building sized turbine and generator are huge enough for you, perhaps some looking around on the Internet would help? If the need is great enough, then it's pretty simple to get big hunks of gear into a jungle.

    Help us out here, Richard and keep your large statements on point and accurate. Real simple stuff.
     
  2. apex1

    apex1 Guest

    If your ability to read would be as big as your mouth Chris, you would have been able to translate this statement right:

    That means in simple words it is impossible. period...

    If your understanding of metal properties would be as big as your mouth Chris, you would know that cast Al from scrap CANNOT be used as a boat hull.

    Which again means impossible. period...

    Go on with your rather insane way to hijack threads, by chasing other members you donĀ“t like. Doug Lord, Ad Hoc, me, for example.

    But stay out of such a thread, where the reason is to assist someone to bring aid to those who cannot help themselves!

    Nobody is interested in your senseless story of turbines in the jungle, and nobody can gain anything from it.

    Get your medication....

    no regards
    Richard
     
  3. SamSam
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    SamSam Senior Member

  4. mental_boy
    Joined: Jun 2010
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    mental_boy Junior Member

    Wow.

    Ok, moving on. I'm going to second steel as a good 3rd world boat building material.

    It's dirt cheap (55 cents a pound in plate form from a supplier here), It can be worked with inexpensive tools and it's easy to repair. Also, if the boat is large enough there is no weight penalty vs other materials.

    Take this Dudley Dix cargo boat for example:

    http://www.dixdesign.com/cargo50.htm
    I don't think it's appropriate for the congo, but it's a good example of what can be done with flat plate steel. I believe the boat has roughly 18,000lbs of steel in the hull, so at 55 cents a pound that's about $10k in steel plate for a 50ft an ocean going vessel.

    The trick is to design a hull that can carry a huge load but has very little drag and is appropriate for the waters there. Not a barge. You'd need to tell us what kind of loads you would like to carry, what kind of speeds would be appropriate, and what kind of water the boat would encounter. Is it all narrow protected rivers? Are there currents?

    Since marine engines are expensive you could just re-purpose a tractor or car or motorcycle engine and run a straight drive shaft. Probably bronze bushings for bearings and the shaft could come above the waterline to skip the need for seals. Prop could be hand made of steel scraps from the hull.
    You could also just hang the engine and prop shaft right off the back like they do in thailand:

    http://images.travelpod.com/users/marzan/thailand_2007.1174578840.p3220374.jpg
    http://www.team-bhp.com/forum/attac...d-smiles-perfect-spot-vacation-1_img_0822.jpg

    Also, since the wood is free, I don't see what is so bad about construction from wood. Boats have been built for millennia without the use of modern paints, sealents, epoxies, etc. And 10K can buy a lot of paints sealants and expoxies. You'd need a sawmill to cut the wood and it would need to be dried properly, which may not be possible depending on the material....
     
  5. apex1

    apex1 Guest

    Sam Sam,

    thanks for enlightening the auditorium!
     
  6. SamSam
    Joined: Feb 2005
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    SamSam Senior Member

    Yeah yeah. I'll delete it so ya'll can sit in the dark again and listen to the story. As the guy says, he's not a boat builder, he's a "social scientist", so good luck on anything useful happening. It seems we had the same problem about 200 years ago.

    [​IMG]
     
    1 person likes this.
  7. apex1

    apex1 Guest

    I guess you got me wrong!

    I meant thank you for the information about the thread opener!

    Most, if not all of us will have got the impression they could help some people to a better life, assisting the "congoriver" member.

    In the light of your post that gets another colour. Maybe the right one!

    Regards
    Richard
     
  8. Squidly-Diddly
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    Squidly-Diddly Senior Member

    continous Rail-Road rails are fused with some mixture of

    Steel and heat producing chemicals(thermite?).

    Never seen it, but I hear they clamp a mold over the rails to be joined, pour in a dry mix, ignite it, and a minute or so later they remove the mold and a minute after that the train roars over the track. (No idea of how the get the steel to form smooth joining surface on the top of the rails, but I'm sure there is trick, maybe something melts the steel granules THEN forces the steel up with overflow vents elsewhere).

    Maybe such a concept could be used to overcome the "heat it all up at the same time" casting problem.
     
  9. SamSam
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    SamSam Senior Member

    All this has been suggested before.

    Use wood

    Use car and truck parts

    Sternwheel drive

    [​IMG]
     
  10. SamSam
    Joined: Feb 2005
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    Location: Coastal Georgia

    SamSam Senior Member

    I sort of regret all the editing I did now. It's sometimes fun to rant and it was kind of a pretty looking one. ;)

    I don't know if he's serious or not. We'll see.
     
  11. apex1

    apex1 Guest

    You still can edit again....:D


    Maybe,

    but that is not the problem.
    A cast AL hull, will not stand the conditions, thats the main prob. And produced from scrap metal on top of that, would make it corrode faster than it can brake.

    Regards
    Richard
     
  12. mental_boy
    Joined: Jun 2010
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    mental_boy Junior Member

    Here's some information from the Bay of Bengal Programme. Part of their goal was to develop planked boats to replace dugout canoes. Planked construction makes for more serviceable boats and more efficient use of materials.

    The boat described here isn't exactly good for cargo, but it seems there is good information on materials selection for the frame, planking, fasteners and caulking. No exotic materials needed.

    Seems you could make yourself most useful by getting a grant to adapt this construction technique to an efficient cargo boat suited to the Congo. The boat would make best use of material available locally. You'd still need to import caulk for the planks, paint and galvanized fasteners. You could also take a some classes elsewhere in woodworking and traditional boat building to make yourself more effective.

    To maximize the utility of the boats you can tap talent in this forum for appropriate hull designs.

    Once you become proficient at constructing the boats, you can set up a workshop that teaches local people to use these construction techniques and build suitable designs.

    http://www.fao.org/DOCREP/FIELD/006/AD529E/AD529E00.HTM

    http://www.onefish.org/cds_upload/1049895976281_wp0077.pdf
     
  13. SamSam
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    SamSam Senior Member

    Here's the boat the Datsun engine is on. 8 x 30' with 1' draft gives somewhere around 14,000 lbs (7 tons) displacement. The guy said he got about 6 miles to the gallon (gasoline). Build it without the cabin, fill it up and away you go.

    The automatic transmission seemed to be real handy. Three speeds forward would give variances between speed and power, plus neutral and reverse. He said he didn't use the throttle much when docking, he'd just downshift.




    [​IMG]
     
  14. hoytedow
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    hoytedow Carbon Based Life Form

    I also agree on the use of wood. In the early days of America, the folks upriver would create large river barges out of wood and float their produce downstream to the cities. There they would sell all the produce, dis-mantle the barge and sell it for the lumber. Then they would walk or ride horses home and do it again. That was free enterprise early 1800's style and I think it might be beneficial for you.
     

  15. apex1

    apex1 Guest

    ...at least...if not for the native people as well...:rolleyes:
     
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