Bow thruster on a Sisu 22

Discussion in '"Pocket" Downeast Boats (14-24ft)' started by RobBaker, Feb 8, 2020.

  1. sockeye

    sockeye Senior Member

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    What model are you installing?
     
  2. BillD

    BillD Captain

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    not that far yet
    I'll have New England Bow Thruster do the install.
    I think they use Lewar
     
  3. Kenneth

    Kenneth Senior Member

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    Glassing the bottom side of the tube is the real PIA part.
     

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  4. RobBaker

    RobBaker Senior Member

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    You did a nice job mine will have a little more room underneath but understand the challenges. Drilled the pilot holes today and the unit arrived today need to measure the tube and get a hole saw next.
     
  5. Kenneth

    Kenneth Senior Member

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    I think a hole saw will create an oblong or egg shaped hole due to the curve of the bow. I made a jig out of threaded rod to mark mine, then cut it out with a jig saw, i'm sure there a other ways to do it.
     

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  6. Toolate

    Toolate Captain

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    Mine was so close to the point of the hull on the bottom that I put a piece of foam core in there and glassed it all together. Was not able to wrap tube entirely because the clearance was so low but it was totally encapsulated and then I think I laid up like 4 overlapping layers of 1708 tabs all around it plus csm Inside and out then faired it with hull and deck with glass fibers from csm mixed in. If there is core remove it so tube is glassed to hull skin in and out. Fun project once you are past the interior grinding stage.
     
  7. Shor2832

    Shor2832 Senior Member

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    Drawing the proper diameter circle on a piece of paper, with center marked, then transferrng to hull makes it easy too.
     
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  8. RobBaker

    RobBaker Senior Member

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    My plan is to replace the pilot drill bit in the hole saw with a steel rod. The rod being long enough to go thru the hull on both sides. Go thru 90% on one side then pull it out and get the other side. If this works it should do away with the oblong shape hole.
     
  9. Genius

    Genius Captain

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    won't work. the hole saw isn't deep enough.
     
  10. RickC137

    RickC137 Senior Member

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    Rob, post a pic of the plug. Want to see how thick the hull is there.
     
  11. RobBaker

    RobBaker Senior Member

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    Genius good post, got me thinking. The standard hole saw is 1 3/4 deep for going thru a 2*4. They make a deeper one FREUD DHS4500 High Performance Hole Saw which is 2 3/8 inch deep which should help me but not resolve the issue you pointed out. Perhaps I can do most of the cut from the outside and finish up on the inside. Time will tell. My tube is small a little over 4.5 inches so that should also help. I'll have my jig saw handy just in case.
     
  12. Roberto

    Roberto Member

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    Rob, did you go with the Lewmar 110TT thruster?
     
  13. RobBaker

    RobBaker Senior Member

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    Yes I did. The motor was almost 2" shorter then the Side-Power.
     
  14. eglicomet

    eglicomet Member

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    Hey Kenneth, can you post photos? I'm doing a minor refit on my old Dyer project and a thruster is on the dream list of upgrades.
     
  15. Brent

    Brent Member

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    My 22 sisu didn't have enough bow in water for one of them.Id practice docking if I was you
     
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  16. RobBaker

    RobBaker Senior Member

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    Brent I’ve studied this enough to determine that a thruster will work on my boat. Stay tuned to this thread should have a 4.5 inch hole within the next two weeks weather permitting it’s cold out there.
     
  17. Kenneth

    Kenneth Senior Member

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    I've not got past the tube install as of yet.
     

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