pivotal drive subsurface or surface all in one

[JPT]

Looking for information on Cam.A Propulsion pivotal drive or something similar that would be easy to manufacture and low cost.Possible to power with twenty horsepower honda or equivelent. Needs to be trimmable for shallow rivers. any information would be appreciated .

[tom kane]

Cam.a.Propulsion the first Practical Trimmable Shaft Drive for powerboats.
Inventor Tom Kane. Conceived 1950`s.Patented New Zealand 1973.The logical way to easily install a shaft drive in a powerboat keeping in mind that a fixed drive will be more easily damaged and be inconvenient to trailer and launch your boat.

Go to www.shareaproject.com search Pivotal Drive or search Boatdesign web site.

[JPT]

Hi Tom and thankyou for your reply. I really like like this idea of yours. I am new to inboard designs like this but would like to build something similar for my plywood boat. Do you run a surface piercing prop? If so, compared to other surface drives is the distance from transom to prop a concern.

[tom kane]

Surface propulsion is best for very fast boating taking as much advantage from reduced drag as possible and all you want running in the water is just the prop and shaft and rear strut.
If you look at fast race boats the prop is relatively close to the transom as are many other surface propulsion drives.
The position of the prop depends most on size and design of the prop.
There are many ways to build a trimmable shaft drive but a trimable drive using the same components as a conventional fixed shaft drive should be easy for any engineer (or non engineer) and if so designed you could use it for surface or sub-surface propulsion.