bow thruster tubes?

Discussion in 'Metal Boat Building' started by Jackphilps, Nov 7, 2009.

  1. Jackphilps
    Joined: Dec 2008
    Posts: 8
    Likes: 0, Points: 0, Legacy Rep: 10
    Location: International

    Jackphilps Junior Member

    Hello there, fitting bow thruster tubes 200mm dia, just intrested in ideas or the 'correct' way to fit them?
     
  2. Submarine Tom

    Submarine Tom Previous Member

    Athwartship at the bow...
     
  3. Jackphilps
    Joined: Dec 2008
    Posts: 8
    Likes: 0, Points: 0, Legacy Rep: 10
    Location: International

    Jackphilps Junior Member

    oh sorry, bow
     
  4. apex1

    apex1 Guest

    Ahh, ja.

    This may become the most informative thread since the invention of foot powder.

    We just must try hard enough.
     
  5. daiquiri
    Joined: May 2004
    Posts: 5,373
    Likes: 252, Points: 93, Legacy Rep: 3380
    Location: Italy (Garda Lake) and Croatia (Istria)

    daiquiri Engineering and Design

    Check this Vetus manual I've enclosed here. You should find the info you need. You can see some informative pics in this site:
    http://www.cantierelatino.com/installazione_elica_di_prua.html
    The site is in italian, but I think those pics are pretty clear even without translation. ;)
     

    Attached Files:

  6. gonzo
    Joined: Aug 2002
    Posts: 15,410
    Likes: 1,000, Points: 123, Legacy Rep: 2031
    Location: Milwaukee, WI

    gonzo Senior Member

    It depends on the hull design. Is it a displacement or planing hull, etc.
     
  7. jehardiman
    Joined: Aug 2004
    Posts: 3,037
    Likes: 550, Points: 113, Legacy Rep: 2040
    Location: Port Orchard, Washington, USA

    jehardiman Senior Member

    I concur with this. You can easily double or triple the drag penalty of the tube by improper placement as well as give yourself a living nightmare of a structural problem. The best case would be to see if the hull designer/manufacturer had already done the work and has recomendations. 20cm is not a small tube to be putting in one of the most highly loaded areas of a vessels structure. Tabbing and reinforcement will be substantial on a glass boat and weld joint design critical to prevent cracking on a metal one.
     
    Last edited: Nov 9, 2009
  8. Jackphilps
    Joined: Dec 2008
    Posts: 8
    Likes: 0, Points: 0, Legacy Rep: 10
    Location: International

    Jackphilps Junior Member

    tubes

    Its an aluminium boat and it has double bow thrusters. i have dimentions and and the tubes ready, thats not the problem, just looking for advice into the correct way to fit the tubes, to get them installed as accurate as possible. If there is a method or procedure?
     
  9. jehardiman
    Joined: Aug 2004
    Posts: 3,037
    Likes: 550, Points: 113, Legacy Rep: 2040
    Location: Port Orchard, Washington, USA

    jehardiman Senior Member

    What type of boat, bow shape (V, spoon, or other), and speed? My gut feeling is to recommend a shell insert just to resolve weld and strength issues as well as improve thrust output. Depending on speed and slamming, just using a corner weld (C2v.2) for the tube/shell connection is not the best way.
     
  10. gonzo
    Joined: Aug 2002
    Posts: 15,410
    Likes: 1,000, Points: 123, Legacy Rep: 2031
    Location: Milwaukee, WI

    gonzo Senior Member

    Depending on shape and speed, a fairing may be adviseable.
     
  11. Jackphilps
    Joined: Dec 2008
    Posts: 8
    Likes: 0, Points: 0, Legacy Rep: 10
    Location: International

    Jackphilps Junior Member

    What type of boat, bow shape (V, spoon, or other), and speed? My gut feeling is to recommend a shell insert just to resolve weld and strength issues as well as improve thrust output. Depending on speed and slamming, just using a corner weld (C2v.2) for the tube/shell connection is not the best way.??


    v hull, the rest of the information is not needed. Everything else has been designed, shell insert allready in place, as is said i have dimentions, all i want to find out is how to cut the hole's for the tubes accuratly, so they sit level and paralell. Is there a tool i can use, is there a method ? sorry if im confusing people.
     
  12. Jackphilps
    Joined: Dec 2008
    Posts: 8
    Likes: 0, Points: 0, Legacy Rep: 10
    Location: International

    Jackphilps Junior Member

    im looking for advice from a builder
     
  13. apex1

    apex1 Guest

    Jack,

    you would have had advice from a builder, if you would provide the info requested!
    But when the "rest is not needed" to quote you, it will be hard to get what you look for!

    Regards
    Richard
    boatbuilder
     
  14. gonzo
    Joined: Aug 2002
    Posts: 15,410
    Likes: 1,000, Points: 123, Legacy Rep: 2031
    Location: Milwaukee, WI

    gonzo Senior Member

    If you need instruction on how to cut a hole level and parallel, this job is way over your head.
     

  15. Frosty

    Frosty Previous Member

    I saw a tip section in a magazine on how to cut the hole level and parallel.

    It was surprisingly easy and obvious with little tools.

    Every thing is easy if you know how to do it!!

    Fairing is always advisable. Keeping the tube deep enough is important --I seem to remember 1 foot min ( I dont know where I got that from) but some power boats will be able to plane with it out of the water which would certainly give you peace of mind that it wasnt dragging you down.
     
Loading...
Forum posts represent the experience, opinion, and view of individual users. Boat Design Net does not necessarily endorse nor share the view of each individual post.
When making potentially dangerous or financial decisions, always employ and consult appropriate professionals. Your circumstances or experience may be different.