Canopus and Sculptor

[Guest]

As for Loddon its got a beta 2203 with a 19x14 prop

 

That's one of the reasons she behaves so well; the water can see the rudder - no hunking disc of bronze alloy in the way, small area prop blades and no daft vertical post either. A lever morse controller with the Beta I guess too - blip blip sorted! Nice

[Tonka]

Surely to get smooth flow to the rudder you need to remove the prop.

 

 

Handling issue sorted

 

 

 

Sell it and go and buy one you can handle before you ruin Canopus with your Modifications

Edited January 1, 2017 by Tonka

[chubby]

Meanwhile up in heaven , the afterlife , or whatever ...having put aside thier earthly differences ...

 

Wernher Von Braun hands Barnes Wallis an ipad with this thread on the screen .

 

" Barnes , Have a look at this load of bollocks " .

[bizzard]

Boats generally steer well going forwards if they steer well going backwards. If when going backwards and you want to straighten up by kicking the arse over with reverse rudder and a burst of forwards throttle and the boat reacts to it reasonably well then usually steering is satisfactory going forwards too. The boat at the beginning of the thread, ''was it Canopus'' where the leading edge of its rudder was miles away from the propeller, I doubt if it could kick the boats arse over very well whilst going astern.

[Dalslandia]

Did someone not got the christmas present they wished for?

[Dalslandia]

All those small trick and tips is used om F1 cars and airplanes, as well as on boats. it does not cost much to do it right from start, but cost some to re-do it afterward when the fabrikator didn't know, or thought he know better.

[ditchcrawler]

 

 

You're right - the flat blade is not so bad for our type of boat, but the prop needs to be close to the rudder, certainly closer than on 'Pus, which means having to remove that vertical post in order to get the prop on and off.

 

Can you not undo the prop and pull the shaft inboard dropping the prop out sideways ?

[bizzard]

How is taking the prop on and off going to get it closer to the rudders leading edge? If you mean by drawing the shaft out more or fitting a longer shaft, you'll probable find that there is then too much exposed shaft sticking out between the tube boss and prop which can if the prop is struck by a solid object put a set in the shaft which means ''bent'' causing unease in the stern tube and a wobbly propeller.

I would leave the prop alone. Knock the bar out and extend the forward balance part of the rudder blade so as to be closer to the prop whilst adding the appropriate amount to the trailing edge of the rudder blade. The added weight will make the tiller a little heavier, but it will respond much better especially going astern.

Edited January 1, 2017 by bizzard

[bizzard]

How is taking the prop on and off going to get it closer to the rudders leading edge? If you mean by drawing the shaft out more or fitting a longer shaft, you'll probable find that there is then too much exposed shaft sticking out between the tube boss and prop which can if the prop is struck by a solid object put a set in the shaft which means ''bent'' causing unease in the stern tube and a wobbly propeller.

I would leave the prop alone. Knock the bar out and extend the forward balance part of the rudder blade so as to be closer to the prop whilst adding the appropriate amount to the trailing edge of the rudder blade. The added weight will make the tiller a little heavier, but it will respond much better especially going astern.

I've had to modify about three boats built by so-called bespoke boat builders in this way, where the rudder stock tube has been fitted far to far aft,. and what a difference, vibrating tiller smoothed out and proper steering response fore and aft. They didn't have that vertical bar though.

Although not particularly deep drafted boats the best steering boats I've steered have been budget boats like Liverpool boats Colcraft, Springer and Harborough marine of any length, especially Harborough marine, which you could steer and maneuver very accurately especially astern.

[MtB]

 

Pride comes before a fall... or an unscheduled excursion up the far bank in my case... I only have time for grinning when stationary!

 

 

It sounds to me as though your steering difficulties are caused by nothing more than going too fast.

 

Slow down and the boat will probably behave beautifully.

[Chertsey]

I've only read the last couple of pages so forgive me if this has been said before, but don't make any modifications until you've given the boat a real chance for you to get used to it - like at least a couple of years. You may need to learn whole new techniques, which you never will if you just start trying to make it into the boat you were previously accustomed to.

 

Also get someone else, who's used to that sort of boat, to have a go and see if they find the same issues.

Edited January 1, 2017 by Chertsey

[Guest]

All mentioned Sarah, thank you. The 26" prop is a variation from the original build and I'll be reverting to a 24" immediately, after that we see what we have. I suspect that'll resolve a number of issues. I'm not expecting her to be a Springer in fancy paint by any means.

 

It sounds to me as though your steering difficulties are caused by nothing more than going too fast. Slow down and the boat will probably behave beautifully.

 

Speeding really isn't an issue in trying to get her to reverse. It wasn't an issue going forwards either, to be fair.

 

Can you not undo the prop and pull the shaft inboard dropping the prop out sideways ?

 

I had assumed that we can't - as I can't move the first shaft out of the way to feed the second shaft back... there's certainly a single UJ about level with the drop-down table in the aft cabin, not sure if there's a complimentary one coming out of the reduction box - I didn't get my nose in there.

[Dalslandia]

 

Here is some simple example of shilling that any blacksmith, should be able to do

 

the more refined classic Schilling and the Icecream cone rudder, one with 20% thick blade that end at 60-80% pf the blade length. and one 25% thick overlayed that goes to 100% length, is said to steer well in reverse.

Edited January 3, 2017 by Dalslandia

[ditchcrawler]

simple schilling 20%.JPGsimple schilling 20%-25%.JPG

 

Here is some simple example of shilling that any blacksmith, should be able to do

 

the more refined classic Schilling and the Icecream cone rudder, one with 20% thick blade that end at 60-80% pf the blade length. and one 25% thick overlayed that goes to 100% length, is said to steer well in reverse.

Didn't Dan make one of these for his boat.

[Dalslandia]

I know Biggles did

[Guest]

I just noted a comment made on a different thread by Dave Moore:

 

"When I first knew Acacia she was fitted with a JP3 (2)? The then owner, Frances Beechey, put the Gardner in after a very near miss with an oncoming boat in a bridge hole....the JP was slower to pick up in an emergency!"

 

Interesting....

[Guest]

I enquired about the correct pivot point for a Schilling rudder, as the forces for this type of rudder are very different to those of flat plate.

 

Our comrade Jan suggested the answer lay between 21.6 and 25.5, based on his own experiences with a Schilling rudder, which he has fitted to his day boat.

 

A kind local friend of mine, a highly knowledgable and qualified naval architect, Slavisa Skipina explained his reasoning fully, and concluded that "to keep you away from the centre of pressure overshoot, is 20-22% (C.P. will usually stay at more than 35% behind the leading edge of the rudder, but can advance to as much as 26-27% at some rudder angles)."

 

I hope that's of assistance for others that may wish to follow this path.

 

Based on the above I'll have a punt on a 22% of chord pivot point, and I'll report back one day if or when I decide to fit one.

 

[alan_fincher]

I just noted a comment made on a different thread by Dave Moore:

 

"When I first knew Acacia she was fitted with a JP3 (2)? The then owner, Frances Beechey, put the Gardner in after a very near miss with an oncoming boat in a bridge hole....the JP was slower to pick up in an emergency!"

 

Interesting....

 

On the other hand there are loaded coal boats towing loaded buttys getting along (and stopping!) very well on JP2 power.

 

If you have seen Towcester & Bideford in the area where Canopus has been, then you would see that Julia and Richard have control of a loaded pair just about as sorted as it is possible to get.

 

The JP2, whilst maybe not extensively originally used in narrow boats, has rightly become just about one of the most favoured engines.

 

If a modern narrow boat copy has a JP2 in, then if everything else is right, it is hard to imagine you could do much better., provided there is room to swing an appropriate prop.

 

I think you are reading too much into things. If I had happened to end up with a JP2 powered boat, I would have considered I couldn't do much better.

 

Anyone who thinks a 4 cylinder Gardner is a better option than a JP2 is, in my view, highly misguided. The one single thing that put me off considering the boat being referred to by Dave was that bonkers Gardner. Had it had a more appropriate engine, I would have pursued it much more keenly when I became aware over 2 years ago that the owner probably wanted to sell it.

[Athy]

 

 

 

If a modern narrow boat copy has a JP2 in, then if everything else is right, it is hard to imagine you could do much better., provided there is room to swing an appropriate prop.

 

I think you are reading too much into things. If I had happened to end up with a JP2 powered boat, I would have considered I couldn't do much better.

 

Anyone who thinks a 4 cylinder Gardner is a better option than a JP2 is, in my view, highly misguided. The one single thing that put me off considering the boat being referred to by Dave was that bonkers Gardner. Had it had a more appropriate engine, I would have pursued it much more keenly when I became aware over 2 years ago that the owner probably wanted to sell it.

This is an unbiased question (although you'll know why I am asking it): do you feel that a JP2 is a better option than a non-bonkers-sized Gardner, such as a 2LW?

[pete harrison]

The JP2, whilst maybe not extensively originally used in narrow boats, has rightly become just about one of the most favoured engines.

Lister JP2's were fitted in quite a few narrow boats during their time in full trade.

 

'British Waterways' modernised a few of their motors with JP2's, and these engines were certainly favoured by 'Barlows' when they were modernising their fleet. Christopher March also fitted a Lister JP2 into HEATHER BELL after acquiring a butty from the Grand Union Canal Carrying Company Ltd. - and their were a few more

[Guest]

Many thanks for that Alan, I appreciate your advice.

 

I've actually chosen the Samofa 2S 108 which seems very similar in characteristics and torque distribution, but with an extended RPM range to achieve 30hp@1500rpm, though I'll most likely limit that to 1300rpm (26.5hp) with the throttle linkage.

 

I reckon the belt driven 110A 24V alternator takes about 4hp, so I'll have 22.5hp (less g/bx & shaft losses) with good torque on hand.

[pete harrison]

This is an unbiased question (although you'll know why I am asking it): do you feel that a JP2 is a better option than a non-bonkers-sized Gardner, such as a 2LW?

I would go for the Gardner 2LW even though they were not used in commercial narrow boats (and I did when I bought NELSON in 1985 for the company I worked for, a boat built in 1980 and used for carrying coal on the River Severn - the 2LW replacing a Kelvin J3 in late 1981 / early 1982)

 

edit - but my first choice would be a 2 cylinder Lister H Series.

Edited January 3, 2017 by pete harrison

[Guest]

You are indeed a man of fine taste Pete, there's one purring here, delightful!

 

[alan_fincher]

This is an unbiased question (although you'll know why I am asking it): do you feel that a JP2 is a better option than a non-bonkers-sized Gardner, such as a 2LW?

 

I would prefer the JP2, because (from my perception!) it was used more frequently than Gardners were, and I would always rather have an engine that has a historical connection, ideally with the boat in question, but at least with working narrow boats generally. I love the big Kelvins for example, as a piece of marvellous engineering, but they just don't feel right to me in an ex working narrow boat.

 

Before Pete points it out, I am aware that at least some Barlow boats acquired Gardners, but I have to admit I don't know what type.

Lister JP2's were fitted in quite a few narrow boats during their time in full trade.

 

'British Waterways' modernised a few of their motors with JP2's, and these engines were certainly favoured by 'Barlows' when they were modernising their fleet. Christopher March also fitted a Lister JP2 into HEATHER BELL after acquiring a butty from the Grand Union Canal Carrying Company Ltd. - and their were a few more

 

It depends, I guess on your definition of extensively, which is the word I used.

 

Do you know what the Gardner(s) was/were that Barlows fitted, please?

edit - but my first choice would be a 2 cylinder Lister H Series.

 

Excellent choice! (But I would say that!).

[pete harrison]

Do you know what the Gardner(s) was/were that Barlows fitted, please?

2L2 - but mostly Lister JP2