Olala!
I've read all the reports, amazing!
I'm speechless at the moment and it takes something!
Keep up the good work!
😮😮😮😮 Michel-C.

Would love to see some annotated photos, just to see how it shud operate ! Please ??

I made a kitchen rudder for my steam launch back in the 80’s. Still works great. I use two servos, one rod steering right and left and the other for opening and closing the clam sell. The servo for opening and closing the is mounted on a bolting shaft the connect to the two clam shell. The servo pulls the shell together rather the push them close. This way it will not bend the clamshell shafts. Hard to explain but if you want, I can send some photos🤔

Herman, good afternoon, sadly I am not able to use any of my ic engines for sailing due to them being banned almost everywhere in the UK.
But I keep them for my vintage display at various vintage shows.
So, until I win the lottery, when I will buy a lake just to sail my vintage boats, then when I'm gone my grandson will own my collection.
Cheers Colin.

Colin a good morning
You must be an extremely lucky man that you still can enjoy sailing with this engine. All over thé place in Belgium it is FORBIDDEN.

Here is my kitchen rudder system, model built in 1949 now waiting for restoration.
Not only for steering, but also controls the speed and reversing.
Don't have a suitable transmitter for it so don't know if it still works.
Engine is a 1.3cc Mills, which is a good runner after a complete rebuild, now part of my vintage motor display.
Cheers Colin.

Hi all, there is a not disimilar system called a 'Kitchen rudder'. This has 2 semicircular cups or half tubes. They are hinged at the top and bottom and can be steered like a rudder or hinge forward to slow and then reverse the boat direction.

They were used on small GB Naval pinnaces when warships carried them.
One of our club members has made a few of them and they work very well.
Roy

Hi Ed you are making a fundamental mistake! If you are trying to remember something never walk through a doorway. This will wipe your memory. Trust me it happens to me!😎
Roy

Lew, I often require memory “updates” as well but now days I am finding they take a long time and seldom deliver results. I often go out to my workshop to fetch something and by the time I get there I can’t remember what I came to fetch.😂

I believe there are many variations of Kort nozzles. Upon updating my memory I found some unusual ones made of multiple pieces welded together. The most unusual was what looked like two semicircular parts, one on each side of the propeller with small rudders fixed on the output side. The whole contraption had limited side movement for steering.

In contrast, a better performing setup is the z-drive with a propeller that runs in one direction only (for efficiency). To reverse, the dive is rotated 180 degrees.

With the depth of the Mississippi River (U.S.) varying so much most of the towboats are limited to a draft of nine feet What most people don't realize is there are large propellers under the boat, so large that the upper edge almost reaches even with the surface of the water. However, that is contained (concealed) in a large concave area in the under side of the hull. You can see that in the attached drawing is part of a complete set of plans I made with the intent of building the "M/V Arne Christiansen". (Shown with Graupner z-drives.)

Lew
Florida, USA

Hi all different drive systems are always interesting.
There is a full size company link at the end on towboats and Z drives.

Back when we had family holidays we all liked travel on the local canals. My wife also worked for Inland Waterways Ltd and we got a 50% discount but that was later.

Our first outing was in more of a scow design than traditional narrow boat and this had a Morris Minor 800cc engine converted to run on gas. This was a Z drive, the engine stayed still and the prop also moved around like a rudder.

Narrow boats frequently have a removeable tiller arm, like bent scaffolding tube, and the connection to the rudder or Z drive looks like a Z as well. So with the tiller removed you had no purchase on the rudder stock to move it.

Of course you took it in when you locked up for the night. On our gas boat you had to lift up a part of the deck to turn on the gas bottles for the engine just in front of where you steer from.

Our instructions were not to bring out the tiller and put it down and then lift the panel up as the tiller would slide overboard into the canal.

We had 2 boats out, my brother in law on the other. He was very senior in the GPO at the time so never listened to instructions, they were for other people. But we did get on well.
The obvious happened and he marched off to a telephone to get help! Me being a'lets see what we can do' type asked the next boat that came by if they could help and the lady produced the largest magnet I have seen on a rope!

Just one plunge of the magnet captured the tiller, I thanked the lady and we started up caught up with marching brother in law picked him up and got on with the holiday.

All on the boat had a job our son was navigator and had planned the route I was captain and cook! My wife was assistant navigator. I would ask son where we were and he would say. My wife would then say "How do you know"?
At the end of the holiday we broke it to her that all the bridges have numbers on! Our youngest who was about 5 then wanted to also have a job and she became the ship's cat.

Regards
Roy

https://www.thrustmaster.net/wp-content/uploads/2013/12/Z-Drives-for-Inland-Towboats-Brochure-2016-page-compressed.pdf

Hi Lew

You are correct but I was referring to the option where they are mounted below the hull, as per the pictures.
There are two types of Kort Nozzles, accelerating and decelerating. Both, as you pointed out, have an aerofoil cross section, the first the curvature is in the inside to accelerate the water flow and the second it is on the outside. The other fact is that the propellers should be designed for Kort Nozzles. The other point of interest is that there are two main types from a steering aspect, fixed with a conventional rudder and moving with one or more rudders attached to the nozzle.

Ed W...

Re: Voith Schneider. "As draught, they are no deeper than Kort Nozzles or Azimuth Drives."

Not completely true being that many Korts and Z-drives are not mounted completely below the hull. In fact I believe that most Kort nozzles are in line with the propeller shafts. There are many real boats out there with the Z-drives no lower than the keel.

First, lets step back a bit. Kort nozzles are the shroud or "ring" around the propeller to direct more thrust along the axis of the shaft and reduce or eliminate the radial thrust caused by the design of the bare propeller. The Kort nozzle can be used with the propeller on a fixed shaft as well as on a Z-drive.

The "shroud" or frame around the VS drive is used to protect the vertical blades from the bottom. For applications in models it seems that the vertical blades would be more prone to weed clogging due to the open sides. Not all VS drives have this shroud.

Having a model boat with a VS drive certainly would attract attention when out of the water. In the water, boats with Z-drives and those with Kort nozzles and flanking rudders come somewhat close as to visual performance, i.e. "dancing around in a circle".

Lately, I have been making my own propellers and Korts. Note that Korts are not a simple ring like a cut off piece of pipe. They typically have a cross-section that looks more like an aircraft wing profile.

Lew
Florida, USA

Love the boat name! You make a good point with kort nozzles. You can use a very thin ply and soak it in glue and tightly bind it several times around the selected round jig, bottle or whatever. Give it some time to dry out and then file or sand the profile and if rigid enough cut a hole for a rudder stock.

Incidently the towboats on the Mississippi had big kort nozzles and sometimes 5000 HP of power. They used to fit close fitting props but as there were so many logs in the water they would jam up. The solution was to go back to round blade props and the engines just chewed up the logs without jamming up.

Roy

Here is my inspirational take on a budget kort nozzle, cost, $0.00, nothing, nada. Anybody can buy stuff, I take great joy in building things with what I've got on hand. I think many people in the R/C boat world feel the same.

I took a plastic medicine bottle of appropriate size and cut it to create a tapered tube. a gently drilled hole secures a piece of 1/8" brass rod so it easily connects to a rudder servo for steering. Then I made two slits to attach the plastic fins. I figured I it it didn't work out I could just replace it with a regular rudder. It actually works really well, better than I thought. It kinda looks O.K. too

Hi Lew
Vegetation could cause problems but there is normally a partial shroud around the vanes. As draught, they are no deeper than Korts Nozzels or Azimuth Drives. The only thing putting me off is the price. 40 years ago I often went out on the harbour tugs in Cape Town in South Africa and all of them had twin Voith Schneider drives, their ability to maneuver was exceptional.

I've seen some videos of the Voith Schneider drives in rc boats. Pretty cool idea! However, I wonder about how they would run in water that has some vegetation in it. They also require deeper water.
Any feedback from someone that has one?
Lew
Florida ⛱️, USA

I have been looking at Kort Nozzels, Schottel Drives, Azimuth Drives and Voith Schneider drives for a project I am planning. In our world the Azimuth Drives are Schottel Drives mode to look like Azimuth Drives due to the size of the motors. Voith Schneider Drives are a crazy price, so I and still thinking about which way to go and until I can really get back in my workshop thinking is all I can do at the moment.
Roy, Great explanation of the drive types

I like it, very creative and interesting. An entirely new class of vessels. Made to sail on seabed

or

It could be a logging tug. (Just made that up, I actually have no idea). 👍👍👍👍

A new update on this boat.
After some thought decided to make a new boat out of the starter. The pictures you now see are the finale result.
I liked the basic look of the hull but it was out of line. The first start was to brake the transom and reset it in line. Cleaned off the decking and built the sides. The pilot house and superstructure were remade in styrene .
The final result turned out very well.
Rick

Thanks to all for the explanation on Schottel and azimuth drives.
len

"A picture is worth a thousand words."

(I have two Graupner schottles, also known as z-drives for a towboat, but never started.)

Lew
Florida ⛱️, USA

Hi Schottel is as described a shrouded propeller that can rotate its direction like a rudder. The drive for it is in the hull.

Azimuth drive is an underwater pod that also turns like a rudder but the motor is contained in the pod.
On the many large cruise ships that are around they may also have a fixed pod drive at the bow and 2 azimuth drives at the stern. The pods are used prop first in direction.
No rudders are used in both of these type of drives.

One of the benefits for the cruise ships is that the big diesels can be arranged around the hull to distribute the weight and also a diesel can be serviced at sea as it is probably one of four or more supplying the power needs.

The diesels all drive alternators that produce eventually a DC current. This goes to a central control and for the engines it is turned into a variable frequency AC which drives the engines which are very similar to brushless motors. It will also supply standard mains AC at 50 htz.

When a cruise ship is in a hot/warm climate the air conditioning may well be as much or perhaps more than the power needed for the engines.
If you check the performance of a cruise ship you will see that in the main cruising speed is about 18 knots, top speed is about 22 knots. Length of ship comes into play as well.

Do not confuse purpose built cruise ships with North Atlantic Liners. I think QM 2 is the last of these and they can maintain 30+ knots and are strengthened at the bow to stand the rough weather in the Atlantic.

A further point is that the quoted tonnage is not the displacement of the ships it is just the Gross Tonnage measured as 1 tonne per cubic meter of usable (what can be sold) space so e.g. the engine room is not included.
So whatever the latest largest cruise ship is and quoted as say 140,000 tons the displacement is a lot less!
Where-as for Naval aircraft carriers it is a displacement measurement.

Well there you are, feel free to pick me up on any errors!

Hope this answers your question. If you want absolute information then Richard Simpson who writes for Model Boats magazine is your man. I wrote an article on the workings of the Queen Victoria at launch and Richard checked it over for me before publishing.
Roy

A Schottel drive is like a large barrel that has no bottom or lid. The drive screw is located in this barrel. The entire barrel is turned to steer. It's a bit simple to explain but I hope you understand it. I don't know the other drive either.

Pardon my ignorance, but what is a Schottel or an azimuth drive?

Having looked at the Fairplay group of tugs, I rather favour one of them. Schottel or an azimuth drive as there is no provision for stern tube or rudder.

The very regular port holes suggest a kit when compared with the assembly, they have been neatly cut.

I suspect it has been the project of an older person feeling a bit bored and perhaps running out of time.....

On balance I would finish her, all of the dodgy work will be covered up anyway and in bright colours and some extra detail in the bridge area she could be transformed.

You say you have Schottel drives with the boat does that include motors? If powerful that might suggest what was needed for the model.

Good luck with the project.
Roy

Newby
It’s your investment and obviously you saw something worthwhile in the model or you wouldn’t have bought it.

The flat bottom for a tug bothers me though with your experience and some imagination you could create a sole plate, add frames, cover them and come away with a different model than you bought.

Check out some tugs on www.towingline.com

You will find tugs of various sizes and shapes.

Have fun!

My opinion is that is someone's attempt to scratch build a tug using their own idea, not from a kit or plans:
○ The deck's camber is too extreme.
○ The alignment of everything is poor.
○ The rise in the steps is not in scale with the pilot house's door height.
○ Filler on the hull at this stage of construction - not yet.
○ Lack of bulwark.
----- and more.

I would toss it - not worth the time.

However, I am glad you posted this. Great to see everyone's input when responding to unknown model boats. Thanks!

Lew
Florida ⛱️, USA

Added 16 Nov 23: At a closer look on my large screen PC I noticed there are a lot of pencil markings for cutting wood pieces which seems to indicate it was not a kit which usually has printed or laser cut edges. Crooked hatches on the sides, again with pencil lines. Might want to look closer at the alignment of the six port holes on the front of the structure. Notice the centerline? Not my cup of tea. Lew

The bottom is flat and is set up to use Schottel drives that came with the buy.
Rick

Again, with my little knowledge I'd reckon a harbour tug

My opinion is a Harb’r tug, looking at the wheelhouse carefully one can see thin windows that look up, which would give the pilot a clear view when approaching a taller vessel.

The photos here indicate a flat bottom, is that true? What does the stern look like below? Could it take twin korts?

Like these lines...but seems like a kit and not a scratch build from plans.

I would say a fishing boat by the shape of the hull

At first glance I thought it was a Billings Boats tug kit. It has the Smit Nederland lines. But not quite. 😉

This could be a tug from the Fairplay group. Here's a link.



https://www.fairplay-towage.group/de/flotte/

From the little I know, I have to say is a tug.😎

This looks like a deep-sea tugboat

NEWBY 7
to me it looks like a harbour tug