World`s First Trimable Shaft Drive.

[tom kane]

That was a quick reply cyclops,But a Merc i/o can not do what a long tail boat or pivotal drive can do or go where want to go.I do not think you could build a i/o for your self.Surface drive sub surface drive is your choice too.Super cavitating props can be used,reliability speed, self maintenance,no relying on service shops,no special expensive parts,make your own props.If your are realy rich you can have a super fantastic model built to order.

[tom kane]

Another pivoting drive shaft with foils fitted to hull.A UK patent.

[tom kane]

A recent patent application.http://www.uspto.gov/web/patents/wee...908350-2005062

[cyclops]

I like a "Tai long tail" much more than any other. 4 moving parts after the transmission. 2 bearings, propshaft and a propellor. What spare parts?

[tom kane]

A pivotal drive can have one prop,one prop shaft,one torque tube, two water lube bearings,one thrust bearing,two cv`s or u/v`s and spline.And you can make it as sophisticated as you want.A stearable and trimable model is not any more complicated,with 20 degrees of trim and 40 degrees of steering.and you can build it yourself.Like you I prefer every thing simple and efficient.

[silverback]

Tom, How about the 'Shorter Drive' of 1800? Edward Shorter was a mechanic who lived in St. Giles-in-the-fields, Middlesex, England. It is reported that Shorter made the device and applied for a patent. I do not know if a patent was issued. The propeller shaft was mounted externally to the hull and had a universal joint so that the propeller could be raised out of the water when the ship was under sail. The float on the end was used to keep the prop from sinking. Moveable stay braces were used for steering.
Reviewing: 1800-- common propulsion was sail and wood outdrive units. This unit probably looked good to ship crews.

[tom kane]

Thanks silverback,I have not seen that set up before it`s similar to the old steam packet drives,except they disconnected the drive for sailing.It is a long time since the Shorter Drive in the 1800`s to the modern s/p drives of today.There does not seem to be many early attemps to make a trimmable drive,even though it is quite simple.Some of the early ones were not very practical for modern speeds as they had U/V`s running in the water and some had motors that swung up and down on the shaft.When I patented the Pivotal Drive there were just two challeges (to which I had to explain my claim differences). from a World search that`s why I am interested in these drives.

[yipster]

long time ago i lived on the river amstel here on a boat as pictured.

that boat was from early 1900 and had a "side drive" of witch i cant find any pics quikly.
it had the old 1 cilinder in the bow, upwards joints went over the deck to the long shaft and screw on the starboard sidedeck.
with a small crane the shaft with prop went down. how deep was "trimmable".
do recall seeing these contraptions used quit often on old inland fraighters.
not what your after here and dont think it was patented but had maybe

World`s First Trimable Shaft Drive.

Does anybody know of any early patents for a trimable shaft drive earlier than 1973.Not including early packet steamers that dis-connected their propeller for sailing.A half hour opperation.

interesting subject!

[tom kane]

Thank`s for interesting info yipster.There were many early drives similar to what you explain and pictures and info I find hard to find.Early drives were Z drives.The motor was on the deck and a shaftwent along the deck,90 degree angle down to prop gear box,90 degree angle through the gearbox.Steam engines was used early on.A trimmable shaft drive straight from motor to prop must be more practical.

[yipster]

a second search gave no pics on the side / Z drive but found tekst mentioning the system worked well in the thirty's.
more than one old skipper reported lower speed and raised fuel comsumption after having newer normal props and engines installed. allthough not horizontal the old side prop worked well in undisturbed water and due to the wheel effect needed a spacer between ship and prop. no stopping or reversing on such a prop or the shaft would take off from the ship.

[yipster]

about that undisturbed water here a rough i've been thinking of for a while, in case its tooo rough and nobody understands:
its a bulb bow slow surface cr prop in need of some bull bars

[tom kane]

Looks logical to me.These days you can have an electronic warning device to protect props.Lift them instantly out of the way or stop them turning or drop down a protective cage.I would prefer you model to an IPS.Very likely coud be modified for small craft.Perhaps two wave piercing hulls either side could Keep the dolphins away.