Wrong Shaft Drive Install.

[tom kane]

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

 

[powerabout]

every stern drive looks like CDK's photo

 

[DCockey]

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

Image from www. off road .com

Most CV joints do not like continuous operation at 30 degree shaft angle.

 

[TeddyDiver]

Again, that's not a CV joint in the picture..

 

[tom kane]

wrong shaft drive install

Again, that's not a CV joint in the picture..

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.

 

[powerabout]

splitting hairs
is the output Contant Velocity with the input, yes

 

[tom kane]

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.

 

[TeddyDiver]

What would you call the 30 degree device in the picture.

Universal joints..
http://en.wikipedia.org/wiki/CV_joint
BR Teddy

 

[viking north]

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

 

[tom kane]

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.

 

[viking north]

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 Tnx. Geo.

 

[CDK]

If you want to go further make your steerable or trimable shaft drive fully rubber mounted.

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.

 

[tom kane]

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.