Has anyone fitted a shilling rudder to there narrowboat

[trev101]

The rudder on my new narrowboat is rubbish so if I have to replace it. Would it be worth going for a shilling type rudder,

has anyone had one fitted if so what difference did it make ?

PS. The boat has hydraulic steering.

[Jen-in-Wellies]

Welcome to the forum.

Calling @IanD!

[trev101]

Hi just trying find information on a shilling rudder

 

[Jen-in-Wellies]

The search box is your friend. It's spelt Schilling.

 

[matty40s]

We are currently restoring to life a 35 year old narrowboat that was abandoned in hard standing in a yard for 10 years.

Once we replaced all the electrics for the engine, starter, alternator, batteries, etc , we managed to get the engine going.

Bringing it into the dock to start stripping the hull down, it was a pleasure to steer, very responsive and simple, including reversing.

Once out of the water, we found the Schilling rudder, and the bulbous front end.

I will take a better picture of rudder in the morning.

 

[MtB]

A half-crown rudder would probably work even better....

 

 

 

[Jon57]

16 minutes ago, MtB said:

A half-crown rudder would probably work even better....

 

 

 

Probably not much change in operation. 

[MtB]

20 minutes ago, Jon57 said:

Probably not much change in operation. 

 

Quid pro quo, then....

 

 

 

[IanD]

14 hours ago, Jen-in-Wellies said:

Welcome to the forum.

Calling @IanD!

 

I've got one on my boat (new-build from Tim Tyler/Finesse) and I'm very happy with it -- it gives light responsive steering and excellent manoeuvrability up to much larger working angles than a flat plate rudder, when pushed right over to 75 degrees or so the prop wash comes out sideways with no forward thrust at all, it behaves more like a stern thruster. Not just my biased opinion, Ricky at Finesse confirmed this compared to otherwise identical boats he's built.

 

In my case there was a second reason for choosing it, which is that it's shorter and sticks out less beyond the stern than a bigger (and less effective) flat-plate rudder -- it's about 200mm shorter front-to back (500mm vs 700mm) and sticks out about 200mm less as a result (only about 200mm past the stern) so I can use a short button fender. This matters on a 60' boat which was designed to go through the short Calder and Hebble locks which are "officially" only 57'6" long, but where you can squeeze a 60' boat through "with care" -- I managed to get through the shortest one without even lifting the fender or having any contact between rudder and bottom gate.

 

I don't know what it would cost to have one made up but IIRC it added about £1000 (inc. VAT) to the cost of mine, considerably more effort to build (multiple plates and a *lot* of welding and grinding) but this is instead of a flat plate rudder so presumably some saving by not building this. Maybe getting a replacement one made would cost more than this?

 

Here's a photo of it, and a drawing in case you want to get one built... 🙂

 

(the small red peg is a stop to prevent it swinging all the way round into the prop when going astern, and the little side steps on the bare hull were later removed because the rudder is a better step for getting out of the water...)

 

Edited March 28 by IanD

[matty40s]

The one one the boat we are working on.

 

[Tracy D'arth]

Is that one of the few Eco hulls built in the '80s to try to reduce bank wash?  I can't remember which hire fleet built them.

 

My rudder is probably worth 5p too.

[dave moore]

Alvechurch experimented with the bulbous bow in the 80s.

[Rob-M]

4 minutes ago, dave moore said:

Alvechurch experimented with the bulbous bow in the 80s.

Beat me to it, I seem to remember they had design input from Edinburgh university.

[trev101]

Hi all 

         I was hoping IanD would reply has it's his drawing I'm going to build from I was just not sure if the length of the rudder was right having looked at other rudders. The 60ft narrowboat is in the making at the moment but the rudder that is on will have to replaced anyway. I've decided to make the rudder out of stainless steel so I will not have to be concerned  about erosion on the thinner  contour profiles, so far the material cost including a one and half meter 40mm stainless bar is about £550 but going on the experience of IanD should be worth it. Thanks for all your comments. 

Edited March 28 by trev101

[magnetman]

I wonder how well these work with the propellor not turning. One of the things I really liked with my 55ft and 72ft narrow Boats were that they both had very good rudder blade size so could easily be steered out of gear/prop not turning. Its really handy to be able to just glide in to the side retaining basic steering ability. 

 

Presumably one can still do this with a Schilling. 

Edited March 28 by magnetman

[matty40s]

53 minutes ago, dave moore said:

Alvechurch experimented with the bulbous bow in the 80s.

It is indeed an Alvechurch, built to an very high spec for a private customer late 80s. 15mm base plate, 8mm sides, BwT, genny etc.

[David Mack]

3 hours ago, matty40s said:

The one one the boat we are working on.

 

Interesting that that doesn't have the fishtail on the trailing edge or the top and bottom horizontal plates that I would expect to see on a Schilling rudder. 

[IanD]

3 hours ago, magnetman said:

I wonder how well these work with the propellor not turning. One of the things I really liked with my 55ft and 72ft narrow Boats were that they both had very good rudder blade size so could easily be steered out of gear/prop not turning. Its really handy to be able to just glide in to the side retaining basic steering ability. 

 

Presumably one can still do this with a Schilling. 

 

You can but it doesn't show the improvement it does with the prop pushing water over it -- Ricky did comment on this, there's not much steerage way with no power on.

 

TBH this is a price I'm willing to pay for better steering with power on -- since I very rarely if ever try to steer a boat with power off (I can "glide" in silence with power on...), I don't really care about this... 😉

 

5 hours ago, matty40s said:

The one one the boat we are working on.

 

 

That's just a low profile aerofoil-type rudder (NACA010?) optimised for higher-speed low-drag hulls with low rudder angles, because this is where most rudder research is targeted. For low speed and high angle applications like a narrowboat you really want a thicker profile with a blunt nose to stop the wake breaking away at large angles; the Schilling fishtail then increases lift and maximum working angle further. There is some increase in rudder drag but this is completely negligible at low speeds and compared to narrowboat hull drag and narrow/shallow water drag.

 

The drawing I started from came from Schilling's later patent and was specifically designed for lower-speed applications where good thrust at high rudder angles is desired -- it's designed to work up to 75 degrees angle, and I can confirm that it does this. It takes a bit of getting use to because it's ingrained into most boaters minds that there's no point pushing a rudder past about 45 degrees because it doesn't really do anything, but once you realise that pushing it over even further works rather well the difference is pretty obvious. I found with it right over you could push the stern directly away from a mooring at right angle to the bank without moving forwards at all, just like a stern thruster (according to Ricky) but a lot simpler and cheaper 😉 

 

Combined with the variable-speed BT I've found I can just move the boat sideways ("crabbing?) with no fore/aft movement, like it's being pushed by an invisible hand... 🙂 

 

1 hour ago, David Mack said:

Interesting that that doesn't have the fishtail on the trailing edge or the top and bottom horizontal plates that I would expect to see on a Schilling rudder. 

It's a standard thin aerofoil rudder, designed for good lift/drag ratio in higher-speed ships.

Edited March 28 by IanD

[magnetman]

I'd not want to lose steering in the event of propulsion failure. Being able to direct the vessel to the side with no power is handy. 

 

 

[IanD]

Just now, magnetman said:

I'd not want to lose steering in the event of propulsion failure. Being able to direct the vessel to the side with no power is handy. 

 

 

You don't *lose* steering, it's just a bit less effective than a big flat plate rudder. The rest of the time (99.99%) it's more effective.

[bizzard]

Emerging from top of a lock gates with lots of debris collected there you need to get speed up in the lock and  coast through in neutral until clear of it using the rudder for some way often, and weed and debris elswhere too especially on rivers with a current running, unless you want a busted prop, dislodged rudder or lots of weed box visits to clear the prop unless you like all that then power through it all.  I'll stick with my large plate rudder.

[IanD]

12 minutes ago, bizzard said:

Emerging from top of a lock gates with lots of debris collected there you need to get speed up in the lock and  coast through in neutral until clear of it using the rudder for some way often, and weed and debris elswhere too especially on rivers with a current running, unless you want a busted prop, dislodged rudder or lots of weed box visits to clear the prop unless you like all that then power through it all.  I'll stick with my large plate rudder.

That's fine, you do that, it's your choice, none of this new-fangled rudder rubbish for @bizzard, hurrah!!! 🙂 
 

(though IIRC the patent's about 60 years old, so it's not exactly "new"-anything...)

 

But please don't assume the Schilling *doesn't* work with no power, it's just a bit less effective than a big flat plate because it's shorter -- I've used it with no power and it steers OK, but you need a bit more rudder angle than a big flat plate. On the other hand it carries on working over to much bigger angles than a flat plate, so I expect it can move the boat just as well, but with a bigger difference in the required rudder movement between power on and off -- so the feel takes a bit of getting used to, like having a rudder that carries on working well past "normal" angles does.

Edited March 28 by IanD

[David Mack]

2 hours ago, bizzard said:

Emerging from top of a lock gates with lots of debris collected there you need to get speed up in the lock and  coast through in neutral until clear of it using the rudder for some way often, and weed and debris elswhere too especially on rivers with a current running, unless you want a busted prop, dislodged rudder or lots of weed box visits to clear the prop unless you like all that then power through it all.  I'll stick with my large plate rudder.

I wonder how the holes in the meccano would affect a @bizzard-built rudder?

🙂

[bizzard]

5 minutes ago, David Mack said:

I wonder how the holes in the meccano would affect a @bizzard-built rudder?

🙂

Block em up with nuts and bolts. ☺️

[blackrose]

6 hours ago, David Mack said:

Interesting that that doesn't have the fishtail on the trailing edge or the top and bottom horizontal plates that I would expect to see on a Schilling rudder. 

 

Yes that's because it's not a Schilling rudder.