Jump to content

Hotchkiss Cones - 'For every craft of every draft'


davidwheeler

Featured Posts

I wonder if these might be good for electric boats on canals with no depth. 

A rebirth so to speak. The patent will have run out so one could get the Shenzen SwanTongYi marine propulsion company to make them. 

Link to comment
Share on other sites

It is a thought but the Cones were designed one hundred years ago. Hydraulic propulsion was nothing new - the Admiralty experimented with this in 1866, but early centrifugal pumps were inefficient, the size of the water jet was large and changing direction was difficult - something of a disadvantage for a destroyer. Thornycrofts built hydraulic machinery for a steam lifeboat in 1888, the idea being to avoid racing engines in heavy seas and the danger of fouling wreckage by a screw propeller. Hotchkiss had some very modest success with the Surf lifeboats and their Dutch equivalent. But reports of the Cones in use were not favourable at all. The advantage of avoiding fouling when launching and beaching was outweighed by the lack of thrust. This had been demonstrated in 1883 when two small but identical torpedo boats were set an experiment: one was fitted with a screw, the other with a hydraulic system. The screw vessel achieved 17.3 knots, the hydraulic, 12.6 knots. A similar test during WW1: 9.58 knots with a screw, 8.9 with the water jet. 

Hotchkiss tried to overcome this disparity of propulsive efficiency. He wasn't the only one. Who can forget the Rees Roturbo Pump? Or the Gill Jet Propeller? What seems to have defeated these efforts in the 1920s was the invention of the screw in tunnel, which provided good protection but higher efficiency.

So, perhaps not the best start-up project, if you are thinking of a Cone rebirth. 

But is there, somewhere, a Cone propelled boat still afloat? I have been looking for years

 

Link to comment
Share on other sites

I remember seeing a very elegant wooden launch in a shed near the Thames some yars ago which had an unusual propulsion system. I think it might have been the Cones running off something like a Vedette engine. Not a big boat. 

It was a restoration job and I don't know if it ever got finished. Wooden gentleman's launch. Lovely thing but a lot of work to restore. 

It may have been something else but I do recall not understanding the setup at the time. This was about 20 yars ago. 

 

Link to comment
Share on other sites

Yes there was and possibly still is a slipper-type wooden launch on the Thames fitted with Cones. I have photos of it among my files. As you say, a very elegant boat.

Heavy infestation of weeds could be a problem. Most cone systems had grills protecting the inlet/outlet rectangle cut into the hull bottom. But clearing was simple - go into reverse and there was usually enough impulsion to throw the weed off. In our experience the more serious problem was a stick or piece of metal drawn or pushed  through the grills when aground. The paddles were of relatively soft metal and they bent easily. But with experience that could be dealt with quite quickly.  Far easier than trying to clear a prop bound tight by fence wire with accompanying post, such as we experienced later on the Birmingham canals. In a later boat.

Most largish stones would be stopped by the grills, but one small crabber working off a Devon beach known for its small pebbles had to be careful when coming ashore because the Cone impellers would suck up pebbles which rattled round the inside, to the consternation of anyone within hearing. The owner of that boat changed to conventional propeller. It got too noisy. And time consuming to clear.

Link to comment
Share on other sites

Well, since this subject seems to have attracted some interest, it may help better understand the principal of the Cone if I set out verbatim what Mr Hotchkiss wrote about it in his 'General Description - The Hotchkiss Cone Propeller - the Only Internal Propeller Which Has Stood the Test of Time. Can be applied to ship propulsion using electrical transmission making ships unsinkable. THE INVULNERABLE PROPELLER INDEPENDENT OF DRAUGHT.'

Here goes:

" The impeller, rotating in the conical casing projects water sternwards through the cutting near the larger end of the cone where the centrifugal force is greatest. The re-action from this continuous discharge takes effect on the cone - the impeller sustaining merely a 'torque'. The re-action is the thrust, and this is reversible to about 75-80% when the direction of thrust is reversed. To maintain the flow, water is sucked into the smaller end of the cutting through the open-ended grids. The water flows in roughly at a tangent to the direction of rotation clearing the grids of any weeds collected upon them. These move towards the open ends and are fed into the cone, from whence they are immediately projected from the discharge stream. The flow may be likened to the passage of a rope around the winding drum of a chain ferry, excepting that acceleration takes place owing to the water following a spiral course and passing from smaller to larger orbits of rotation, thus gaining velocity to the point of discharge, and so producing the thrust. The initial momentum of the water relative to the moving hull is not wasted, but forms a part of the final discharge velocity. The theory of propulsion is the same as that of the paddle and the screw in that Weight x Velocity/ g represents the thrust."

So there we are. I trust that this clears up any queries about Cone operation.

  • Greenie 1
Link to comment
Share on other sites

So to clarify, the opening in the hull extends the full length of the cone, but the impeller is fitted only in the large end.

If fitted to a wooden narrow boat bottom which is some 3" thick, how is the opening shaped so that the edge of the bottom planking doesn't obstruct the water flow?

Link to comment
Share on other sites

Cones were designed to fit the individual hull profile for which it or they were required. Most of the vessels fitted with cones were designed by Donald Hotchkiss.

It would, I think, have been easy to weld a flange around the cone, effectively lowering the paddles so that on rotation the outer edge of the paddle was just flush with the outer edge of the bottom plank, to get maximum exposure without risk of damage when taking the ground. Certainly I remember lying underneath a Surf lifeboat and noting that the outer edge of the paddles would have only just have been within the hull shape. That was not a flat bottom, and the shape of the cone was adapted to it. 

Whether a 3" recess would have materially affected the performance I just don't know. As I have tried to explain, the conversion of narrowboat butties to Cone propulsion came very late in the day.  I have found no evidence at all, over the years, of Donald Hotchkiss being involved in any post WW11 canal boat installation. He was quite an effective publicist and I would have expected him to have promoted their use in narrowboat butties, had he been aware of the opportunities. I don't know who started installing them.  I know more about how he, an individual working entirely on his own, managed to get contracts in Poland, South America and the Far East, and elsewhere, than how his invention came to be installed in our own boat.

Link to comment
Share on other sites

9 minutes ago, davidwheeler said:

Cones were designed to fit the individual hull profile for which it or they were required. Most of the vessels fitted with cones were designed by Donald Hotchkiss.

It would, I think, have been easy to weld a flange around the cone, effectively lowering the paddles so that on rotation the outer edge of the paddle was just flush with the outer edge of the bottom plank, to get maximum exposure without risk of damage when taking the ground. Certainly I remember lying underneath a Surf lifeboat and noting that the outer edge of the paddles would have only just have been within the hull shape. That was not a flat bottom, and the shape of the cone was adapted to it. 

Whether a 3" recess would have materially affected the performance I just don't know. As I have tried to explain, the conversion of narrowboat butties to Cone propulsion came very late in the day.  I have found no evidence at all, over the years, of Donald Hotchkiss being involved in any post WW11 canal boat installation. He was quite an effective publicist and I would have expected him to have promoted their use in narrowboat butties, had he been aware of the opportunities. I don't know who started installing them.  I know more about how he, an individual working entirely on his own, managed to get contracts in Poland, South America and the Far East, and elsewhere, than how his invention came to be installed in our own boat.

Years ago I was told that in at least one instance the cones fitted in a narrow boat were second hand, salvaged from a lifeboat. While that might have made for a cheap conversion to a motorised boat, it probably wasn't the best arrangement for efficient propulsion.

Link to comment
Share on other sites

5 minutes ago, davidwheeler said:

But is anyone still using the system?

 

I'd suggest waking up that thread on the ships forum I posted earlier might well yield some results.

 

There  are some seriously knowledgeable peeps on there. For example there is a long thread on there about the cruise liner "Dominion Monarch" (scrapped in 1963) from which one of my engines was supposedly obtained from one of her lifeboats. Every bit as esoteric as Hotchkiss cones, I'd have thought.

Link to comment
Share on other sites

I know that a pair of cones are fitted in the NB Chance II, I am not sure just what has happened to this historic craft, I think two lad had bought it and had it lifted out onto the bank somewhere on the welsh cut.
The cones are actually massive and were mounted where the cross bed should be with the engine in front of that. I attach two very poor images.  We went to see just how much work was required to look after her in August 2011.  The answer - a total rebuild, someone else bought her and they lived on her in Chester for about 5 years then these two lads acquired her, I believe. There is a chance (no pun intended) that they survive.



DSC01505.thumb.JPG.f79ab35616559492bc1f5de10e8d5d50.JPGDSC01506.thumb.JPG.5c92b5414b33cc05bb36f69aafc0cad6.JPG

  • Greenie 1
Link to comment
Share on other sites

Brilliant. Thank you for that. Just what I need. 

We came across Chance 11 on the Shropshire Union, just by the junction. It looked dreadful. Roofing felt and tarpaulins laid along the top, plates along the sides and rot. The hull was hogged. It was a sad sight. There were some handwritten notices in one of the windows but condensation had blurred them. One printed notice, giving the known history and ending " now fitted with a (blanked out) engine and Hotchkiss cones, rather than a propeller, as a means of propulsion." It was 1st September 2015.

n.b Spey, now, is that the Clayton tar boat? I remember them on the Shropshire Union in the 1950s. We met a pair in a narrow stretch near High Bridge. I was steering a Canal Pleasure Craft boat. To get out of their way, I hit something hard in the bank and drove a hole in the side of the boat. It was only a small hole and Holt Abbot the CPL owner was very nice about it. I was twelve at the time. But I haven't forgotten it. The last time we saw Spey was in 1999 on the Macclesfield just after we had taken delivery of our new boat. Oh well.

 

Link to comment
Share on other sites

Well thank you to everyone who has responded to this request for information. It all  helps.

Now, if you don't mind, I will indulge in some boatnostalgia and tell you about boating in the 1950s and early 1960s. Anyway, our style of boating.

My father was by way of inclination and experience a sailing man. With three young children he decided that holidays needed to be provided for and sailing would be too expensive. So in 1955 we had a week on 'Stourvale', one of Canal Pleasure Craft's fleet, and the following year, two weeks on 'Bredon Hill'. When I bashed the hole in the hull on meeting a pair of Clayton boats. As well as other adventures. But we got to Llangollen. Canals were the answer. We lived in Devon. The nearest canal with access to others was the Stroudwater. 100 miles away. It just happened that in late 1956 there was a boat for sale there, with its own mooring. This was 'Somerset', a Lees & Atkins butty built for FMC in 1930 and passed over to DIWE in 1949 and sold shortly after that. Between 1949 and 1956 she was converted. The boatman's cabin was left as built, then an area of deck and then the coachhouse.  In its day quite comfortably fitted out with saloon/ galley, three double cabins with bunks from a RN depot, washbasin in each with running water, electric light, and forward a lavatory with a Simpson Lawrence flushing toilet. Then the bows. It all looked pretty good. The engine, a Morris Marine Navigator, beautifully painted blue with lots of brass piping. And the Cones forward of it. Perfect. My father bought her on the spot. We did not have a survey. We did not to a test run, because it was too windy.

The idea was to cruise into the Midland canal network during the holidays, and come back to Saul and the Stroudwater for the winter. Right from the start, things did not go to plan. 

Our experience on the Gloucester & Berkeley soon demonstrated that the boat was underpowered. And vulnerable. The Ship Canal was not the place for such boats as ours. Albeit everyone we came into contact with was helpful, be it gate keepers, barge and tug crews, or Gloucester dock staff. When we got stuck, somehow the message got passed along the Canal, and barges slowed where they could, and the smaller ones offered a tow. On one occasion, with the engine broken down again, we hoisted a small sail on the coachhouse roof and managed to gain sufficient way to straighten the boat in the face of a Regent tankbarge. 'Regent Linnet', it was. They towed us back at high speed, our flat bottom planing along the surface. We were lucky to survive that. We were probably a nuisance. But nobody said anything.

But where our vulnerability really hit home was on the River Severn above Gloucester. 

One morning in April 1957 we locked out of Gloucester Dock, onto the Severn. We were told to wait for a tanker. We tied up above the lock and waited for the tide to slacken. After a while with no change of stream, we followed two grain barges up the East Channel, very slow against a strong flow. At the mouth of the West Channel, in high wind we met the full flood tide and stormed upstream at 10 knots or so surrounded by great tree trunks and other violent debris. Above the tide, we hit the stream again and slogged on for hour after hour, making precious little headway. At last we reached Tewksbury after rising up the most enormous lock we had ever seen, entered the River Avon and paused for breath. The boat was not suited to the River Severn. We had been lucky.

That is enough for now. I will continue tomorrow unless a moderator tells me to stop.

  • Greenie 4
Link to comment
Share on other sites

35 minutes ago, davidwheeler said:

...

That is enough for now. I will continue tomorrow unless a moderator tells me to stop.

Well, at least it has context abut boaty things, which is more than can be said for many long running posts  on this so-called "boaty" forum. :boat:

 

Howard

Link to comment
Share on other sites

2 minutes ago, howardang said:

Well, at least it has context abut boaty things, which is more than can be said for many long running posts  on this so-called "boaty" forum. :boat:

 

Howard

 

 

Seconded. The thread is fine. 

 

In fact if any mod objected to it (which I'm sure they won't), the membership would object to the mod's objection! 

 

 

  • Greenie 1
Link to comment
Share on other sites

Okay nobody has objected so far, and it is raining, so I will go on....

The next day, Good Friday, when trying to start we found that a key had sheered on the shaft. A local boatyard drilled a hole and inserted a pin. So all is now well.

Off we went. Just south of Strensham, another fuel blockage. After an hour of blowing and sucking, we start again, aiming for Pershore. There is a nasty scrunching noise from the engine room - the pin inserted that morning had sheared. We are stuck again. A passing launch gave us a tow to Eckington Bridge. An engineer, holidaying on 'Grey Eagle' of Bathhursts, stopped and thought it could be fixed with the right bits. He had them in his workshop but that was in Dagenham. At 7.30 p.m. on Good Friday evening a man from Bredon came out and rammed in lots of keys and wrapped them in with tape. For nothing. He refused point blank, saying it had made his day for him.  On Easter Saturday, we set off again, escorted by the engineer on his holidays. This kind gentleman waited patiently while we extricated ourselves from the bank at Swans Neck and out of the way of a group of fishermen whose sport was held up by us shoving away with boathooks in muddy water, against  the wind pressing our 70 feet firmly back in front of them. As if to warn us that we were not doing very well at all. Above Nafford Lock there was already play in the shaft. So we stopped, and 'Grey Eagle' went on its way. A decent bloke. They all were, we found.

So in addition to problems with the Cones, we had problems with the engine. And other bits. If all this had happened on the Severn....

But we get back to Tewkesbury, and leave the boat in the hands of a local marine engineer to fix the problem with the shaft. He hints that the engine could be replaced by a diesel which would be more reliable. My father decided that that was a good idea. So out came the lovely Morris Navigator and in went a new BMC Commander diesel. Heavier. Noisier. But reliable. But costly.

Tomorrow, subject to objections, we will go on up to Worcester and onto the narrow canals. But in fact, we do not.

  • Greenie 1
Link to comment
Share on other sites

An adventure indeed! And many thanks for sharing David. There cannot be many who were boating for 'pleasure' in the early sixties able to recall such details. I have met one or two folk who would have bought SOMERSET at the drop of a hat. How we learn from experience!

Link to comment
Share on other sites

On 23/04/2023 at 08:00, davidwheeler said:

n.b Spey, now, is that the Clayton tar boat? I remember them on the Shropshire Union in the 1950s. We met a pair in a narrow stretch near High Bridge. I was steering a Canal Pleasure Craft boat. To get out of their way, I hit something hard in the bank and drove a hole in the side of the boat. It was only a small hole and Holt Abbot the CPL owner was very nice about it. I was twelve at the time. But I haven't forgotten it. The last time we saw Spey was in 1999 on the Macclesfield just after we had taken delivery of our new boat. Oh well.

 

Would have loved to have seen them trading but missed them, THe first family holiday to do the BCN was not till 1967.
NB Spey is basically a new boat since then, starting in 2010 we rebuilt the whole front end, and since then we have rebuilt the whole of the back end, finishing of earlier this year by putting in a new Counter block and set of uxter boards. Job not finished as the cabin has now started to leak, and we last rebuilt that over 20 years go.
 

Link to comment
Share on other sites

12 hours ago, Ian Mac said:

Would have loved to have seen them trading but missed them, THe first family holiday to do the BCN was not till 1967.
NB Spey is basically a new boat since then, starting in 2010 we rebuilt the whole front end, and since then we have rebuilt the whole of the back end, finishing of earlier this year by putting in a new Counter block and set of uxter boards. Job not finished as the cabin has now started to leak, and we last rebuilt that over 20 years go.
 

 

Like Trigger's broom then... 🙂

Link to comment
Share on other sites

On 23/04/2023 at 11:24, howardang said:

Well, at least it has context abut boaty things, which is more than can be said for many long running posts  on this so-called "boaty" forum. :boat:

 

Howard

 

On 23/04/2023 at 11:28, MtB said:

 

 

Seconded. The thread is fine. 

 

In fact if any mod objected to it (which I'm sure they won't), the membership would object to the mod's objection! 

 

 

 this thread is interesting, polite and non-controversial - we can't be having that! :D 

 

If all threads were like this we'd be out of a job... :o 

 

Seriously, it's a fascinating subject, keep it going - although I won't be fitting cones in Juno anytime soon

  • Haha 1
Link to comment
Share on other sites

  • 2 weeks later...

Create an account or sign in to comment

You need to be a member in order to leave a comment

Create an account

Sign up for a new account in our community. It's easy!

Register a new account

Sign in

Already have an account? Sign in here.

Sign In Now
  • Recently Browsing   0 members

    • No registered users viewing this page.
×
×
  • Create New...

Important Information

We have placed cookies on your device to help make this website better. You can adjust your cookie settings, otherwise we'll assume you're okay to continue.