Wrong Shaft Drive Install.

Discussion in 'Inboards' started by tom kane, Mar 11, 2013.

  1. tom kane
    Joined: Nov 2003
    Posts: 1,767
    Likes: 48, Points: 58, Legacy Rep: 389
    Location: Hamilton.New Zealand.

    tom kane Senior Member

    Wrong Shaft Drive Install

    How about a 30 degree shaft angle joint.Build a steerable,trim able shaft drive.

    Image from www. off road .com
     

    Attached Files:

    Last edited: Mar 24, 2013
  2. powerabout
    Joined: Nov 2007
    Posts: 2,913
    Likes: 63, Points: 48, Legacy Rep: 719
    Location: Melbourne/Singapore/Italy

    powerabout Senior Member

    every stern drive looks like CDK's photo
     
  3. DCockey
    Joined: Oct 2009
    Posts: 4,928
    Likes: 455, Points: 83, Legacy Rep: 1485
    Location: Midcoast Maine

    DCockey Senior Member

    Most CV joints do not like continuous operation at 30 degree shaft angle.
     
  4. TeddyDiver
    Joined: Dec 2007
    Posts: 2,580
    Likes: 123, Points: 73, Legacy Rep: 1650
    Location: Finland/Norway

    TeddyDiver Gollywobbler

    Again, that's not a CV joint in the picture..
     
  5. tom kane
    Joined: Nov 2003
    Posts: 1,767
    Likes: 48, Points: 58, Legacy Rep: 389
    Location: Hamilton.New Zealand.

    tom kane Senior Member

    wrong shaft drive install

    What would you call the 30 degree device in the picture from www.offroad.com.? They call it a Conway CVX-30 constant velocity joint. Who is afraid of high angles.
     
    Last edited: Mar 26, 2013
  6. powerabout
    Joined: Nov 2007
    Posts: 2,913
    Likes: 63, Points: 48, Legacy Rep: 719
    Location: Melbourne/Singapore/Italy

    powerabout Senior Member

    splitting hairs
    is the output Contant Velocity with the input, yes
     
  7. tom kane
    Joined: Nov 2003
    Posts: 1,767
    Likes: 48, Points: 58, Legacy Rep: 389
    Location: Hamilton.New Zealand.

    tom kane Senior Member

    Wrong Shaft drive Install

    An easy way to check power requirements of a C/V or Twin U/V joint and other components for a shaft drive is to hook them up to an electric motor with an Ampmeter to show what current is being used
    You can see the power changes as you move the drive through the different angles and you can see the difference between a dry gear box and a wet box.
    Post image latter.
    In practice where this electric motor is flat motor in boat would be at 10 degrees.With 10 degrees combined in the C/V... Marine twin U/V joints and sliding spline giving shaft angle of 20 degrees or less if required.
     

    Attached Files:

    Last edited: Mar 27, 2013
  8. TeddyDiver
    Joined: Dec 2007
    Posts: 2,580
    Likes: 123, Points: 73, Legacy Rep: 1650
    Location: Finland/Norway

    TeddyDiver Gollywobbler

  9. viking north
    Joined: Dec 2010
    Posts: 1,867
    Likes: 90, Points: 48, Legacy Rep: 1146
    Location: Newfoundland & Nova Scotia

    viking north VINLAND

    When space allowed and the customer had the cash my choice has always been an Aqua Drive coupling. I was seriously considering laying out the $1500 or so bucks again for my own build but the alternatives being posted here has seriously caught my attention.
    In the old days a typical fishing boat sporting the old "make & Break" required as perfect an in line set up as mortal man could achieve. The engine was bolted solid to the beds (no rubber mounts of any kind. The crank flange was bolted directly to the shaft flange. Using a feeler gage,one rotated the engine by hand while shimming between the engine and it's beds for equidistant spacing between and 360deg. around the two flanges. This was no easy feat as you also had to support the shaft at the midpoint of it's gravitational sag. Once perfection was achieved ya bolted the two solidly face to face. Possibly this was the basis of the in line tradition :D
     
    1 person likes this.
  10. tom kane
    Joined: Nov 2003
    Posts: 1,767
    Likes: 48, Points: 58, Legacy Rep: 389
    Location: Hamilton.New Zealand.

    tom kane Senior Member

    Marine twin U/V`s with a sliding spline and back to back U/V`s (more compact) can do all the necessary dampening with soft mounts and not suffer the problems inherent in some of the expensive drives being offered. Mechanical joints do not suffer from rubber hardening and position memory developed in rubber dampening which bring back vibration.

    The ideal set up is soft rubber engine mounts, soft rubber thrust bearing, soft rubber stern tube,soft rubber rear prop shaft mount which is easily achieved. If you want to go further make your steerable or trimable shaft drive fully rubber mounted.

    Drives like you mention need off set too for longer life and are not trouble free.
     
  11. viking north
    Joined: Dec 2010
    Posts: 1,867
    Likes: 90, Points: 48, Legacy Rep: 1146
    Location: Newfoundland & Nova Scotia

    viking north VINLAND

    The off set and a bit of maintenance I can handle -- but I'm too old to produce another number one son to sell for the purchase price :D Tnx. Geo.
     
  12. CDK
    Joined: Aug 2007
    Posts: 3,324
    Likes: 148, Points: 63, Legacy Rep: 1819
    Location: Adriatic sea

    CDK retired engineer

    For an articulate shaft the CV joint must be at least partly outside the hull, just like an Arneson drive. Because nobody wants bellows in such an awkward place and a reliable one has not yet been invented, the whole construction must be stainless, tungsten, titanium or whatever is even more expensive and hard to machine. The same goes for steering, trim cylinders, hydraulic hoses and fittings.

    A very expensive, ridiculous alternative for a conventional rudder.
     

  13. tom kane
    Joined: Nov 2003
    Posts: 1,767
    Likes: 48, Points: 58, Legacy Rep: 389
    Location: Hamilton.New Zealand.

    tom kane Senior Member

    Wrong shaft Drive Install

    I prefer a trimable shaft drive for the many reasons you must be able to think of. Swinging a steerable drive does not give quick response in many sea conditions. There are so many ways of building this type of drive you can easily design your own with all of you innovative ideas and certainly find fail safe seals a plenty these days and better than what already exists and not expensive.

    Google stainless steel bellows seals gives some idea what seals are available of highest quality but not used in the marine environment.
     

    Attached Files:

    Last edited: Mar 30, 2013
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.