Middle northwich bottom construction

[Chris Pink]

I have to dock a middle Northwich butty to do some plating on the bottom. I am trying to get some reference for the construction so we can plan the steel beforehand.

 

So I am after photos or true drawings of the bottom of the boat. I am particularly interested in the following;

 

The construction underneath is a shallow V with rounded chines and a v-shaped keel forging. there are riveted straps that join the chine to the keel which, if my memory serves, mirror the knees inside. But I need to confirm the size and spacing of these straps as it is my intention to make plates welded to the straps, chine and keel.

 

The original plates are behind these straps so would be cut out afterwards.

[AMModels]

I believe Laurence Hogg has copies of the plans available to buy from his ebay shop, someone will probably be along who can confirm that.

 

If you are able to I would love to know which butty you will be working on for my records.

[IanM]

Laurence has some pictures in this topic which might help...

 

http://www.canalworld.net/forums/index.php?showtopic=34935

[stagedamager]

I think it may be Triagulum / Kestrel???

[alan_fincher]

The construction underneath is a shallow V with rounded chines and a v-shaped keel forging. there are riveted straps that join the chine to the keel which, if my memory serves, mirror the knees inside. But I need to confirm the size and spacing of these straps as it is my intention to make plates welded to the straps, chine and keel.

Perhaps I'm simply not understanding, but from what I know of Sickle, and from pictures of Tycho and particularly those of Tucana on her side, I'm not following the descriptions of either the "v-shaped keel forging" bit, or those "straps".

 

The boats seem to me to have little more at the mid point of the base than a slight folding of the steel. I thought there was never a proper keel or keelson, and that's why they originally had a wooden beam, supported by L-shaped riveted brackets, to support the shuts. (And clearly removed in several of those used for non carrying purposes).

 

Apologies if I have totally failed to understand the original post, but, as a Middle Northwich owner, I'm confused, and would like to understand!

[Laurence Hogg]

Perhaps I'm simply not understanding, but from what I know of Sickle, and from pictures of Tycho and particularly those of Tucana on her side, I'm not following the descriptions of either the "v-shaped keel forging" bit, or those "straps".

 

The boats seem to me to have little more at the mid point of the base than a slight folding of the steel. I thought there was never a proper keel or keelson, and that's why they originally had a wooden beam, supported by L-shaped riveted brackets, to support the shuts. (And clearly removed in several of those used for non carrying purposes).

 

Apologies if I have totally failed to understand the original post, but, as a Middle Northwich owner, I'm confused, and would like to understand!

 

No you are right Alan, Tucana has lost her "keelson" too with just the remains of the mounts, The butt straps are forged into a vee along with the plate I believe its around 5 degrees. The chines are probably rolled steel. The only existing drawing that I know of for the "E" type boat shows more or less the cross section, but in reality there are slight variations to be found. Not the best boat to be re bottoming by a long way.

[Derek R.]

. . any use?

 

 

 

Edited October 30, 2012 by Derek R.

[Speedwheel]

[alan_fincher]

A couple from Matt Parrott from Sickle's restoration......

 

 

[Chris Pink]

Perhaps I'm simply not understanding, but from what I know of Sickle, and from pictures of Tycho and particularly those of Tucana on her side, I'm not following the descriptions of either the "v-shaped keel forging" bit, or those "straps".

 

The boats seem to me to have little more at the mid point of the base than a slight folding of the steel. I thought there was never a proper keel or keelson, and that's why they originally had a wooden beam, supported by L-shaped riveted brackets, to support the shuts. (And clearly removed in several of those used for non carrying purposes).

 

Apologies if I have totally failed to understand the original post, but, as a Middle Northwich owner, I'm confused, and would like to understand!

 

Excellent pictures, thanks to everybody.

 

in the GU section drawing, kindly sent by Mr Hogg, a "keel doubling plate 6" x 1/4" coppered steel is shown" - my memory, which should be better than it is and why o why didn't i take pictures when i had the chance - ah yes I remember it was because I was upside down in wet mud with black gloop dripping in my hair - anyway, my memory is that that piece is present on the boat i need to work on. Derek's pictures (Tucana?) show no rivets in the middle so an internal exploration may show more.

 

What I could do with now if anyone has access to the bottoms is the distance from chine piece to chine piece including the 'V' in the main run of the boat, ie what size sheet is needed to bridge the whole (if there is no doubling plate) and the distance between butt straps along the length of the bottoms

 

There is no internal steel keelson and the wooden one is very much shutt support.

 

I am not sure about the spacing of the butt straps shown in Derek's photo but my memory (that thing again) is that the overplating that has been done already used those straps.

 

 

incidentally does anyone know the rationale behind the different classes of GU boats? why a middle class? and what were the Star class boats intended for?

 

 

..

Edited October 31, 2012 by Chris Pink

[mykaskin]

incidentally does anyone know the rationale behind the different classes of GU boats? why a middle class? and what were the Star class boats intended for?

 

I can only assume that the stars were lacking in some way, just the like the Royalty's before them. At a guess, they wanted to more easily carry coal which takes up a fair amount of room to load a boat fully and why slack boards were used on smaller boats, and that they were worried about the boats getting stuck. I don't know though.

 

Royalties probably didn't carry enough on a particular draft due to having to cart loads of extra weight around in dry side, and the swim is a bit short which isn't great for stopping, they are also a little on the deep side, but I wouldn't expect the last two to be such a problem in those days.

 

Mike

Edited October 31, 2012 by mykaskin

[alan_fincher]

incidentally does anyone know the rationale behind the different classes of GU boats? why a middle class? and what were the Star class boats intended for?

I suppose even the "Small" "Stars" represented a general increase in depth of hull-side over much of what went before, and I don't think were anything other than an attempt to come up with something slightly more modern, but still just a general carrying boat. They still tend to show considerably more freeboard loaded than say a FMC boat, don't they, (although the "Spice Boys" do seem to like to push their luck with Archimedes and Ara!!).

 

The Town's do seem to some degree to base their existence on an idea that the modernisation program on the GU in the 1930s was going to result in being able to operate efficiently on greater draughts, and hence (obviously) to get economies of scale by carrying bigger loads.

 

The reality seems to be that whilst there is some record of large tonnages being carried, (63 tons of wheat, possibly to Wellingborough, seems to stick in my mind, but that's a guess!), in reality the Towns were seldom loaded with much more than the Stars.

 

An odd trade off seems to be that on a full load of something that didn't need covering, you perhaps didn't need to sheet the "big" boats, because they still had a lot of side showing. Look at pictures of the Blue Line fleet on the Jam 'Ole traffic. The wooden motors, and the wooden butties that remained in use usually had full side cloths up when loaded - replacement "Town" motors like Renfrew don't even show side cloths fitted, let alone used.

 

The 8 Middle Northwich pairs do seem a bit of an oddity. Some sources say they were designed to also be suitable to work at river estuaries, but quite why their different design should have made them suitable for that is unclear to me, and I'm not sure I'm convinced. I'd almost prefer to think they though "let's try a slightly different design on these, to evaluate whether it makes them any better or worse than a traditional flat bottomed boat".

[josiejo]

the wakehams taurus is at bulls bridge you could ask them 07774166497 as its empty waiting to be loaded jo

[Derek R.]

Excellent pictures, thanks to everybody.

 

in the GU section drawing, kindly sent by Mr Hogg, a "keel doubling plate 6" x 1/4" coppered steel is shown" - my memory, which should be better than it is and why o why didn't i take pictures when i had the chance - ah yes I remember it was because I was upside down in wet mud with black gloop dripping in my hair - anyway, my memory is that that piece is present on the boat i need to work on. Derek's pictures (Tucana?) show no rivets in the middle so an internal exploration may show more.

 

What I could do with now if anyone has access to the bottoms is the distance from chine piece to chine piece including the 'V' in the main run of the boat, ie what size sheet is needed to bridge the whole (if there is no doubling plate) and the distance between butt straps along the length of the bottoms

 

There is no internal steel keelson and the wooden one is very much shutt support.

 

I am not sure about the spacing of the butt straps shown in Derek's photo but my memory (that thing again) is that the overplating that has been done already used those straps.

 

 

incidentally does anyone know the rationale behind the different classes of GU boats? why a middle class? and what were the Star class boats intended for?

 

 

My shots are of TYCHO, as are Speedwheel's after the bottom had been overplated from beneath. The red oxide is on the original bottoms, and the short longitudinal pieces had angles on them (cut off at some point) to locate a timber to support shutts, not a kelson as such.

 

From memory when on dock ten years ago, there was no visible 'extra' steelwork under the bottoms.

 

I had thought maybe the overplated butt straps athwartships might be the 'join' when shortened in 1942, but of course it does not extend up the hull sides.

 

Edited to add:

 

Looking back at the TUCANA thread, the whole bottom is shown with the boat on its side. Nothing other than butt straps athwart beneath.

Edited October 31, 2012 by Derek R.

[David Mack]

The Town's do seem to some degree to base their existence on an idea that the modernisation program on the GU in the 1930s was going to result in being able to operate efficiently on greater draughts, and hence (obviously) to get economies of scale by carrying bigger loads.

 

I'm sure I've read somewhere that the Towns were intended to go out on the Thames to load at docks other than Limehouse, and so were given greater freeboard.

[alan_fincher]

I'm sure I've read somewhere that the Towns were intended to go out on the Thames to load at docks other than Limehouse, and so were given greater freeboard.

Yes,

 

I have seen that too.

 

How that differs from "estuarial" use sometimes attributed to the "Middle" "Stars", I'm not sure, though!

[Laurence Hogg]

 

The 8 Middle Northwich pairs do seem a bit of an oddity. Some sources say they were designed to also be suitable to work at river estuaries, but quite why their different design should have made them suitable for that is unclear to me, and I'm not sure I'm convinced. I'd almost prefer to think they though "let's try a slightly different design on these, to evaluate whether it makes them any better or worse than a traditional flat bottomed boat".

The reason for the vee bottom on the eight pairs was relativly simple. A loaded flat bottom boat will "stick" in the mud if a tidal river dries out, even with ropes passed under the boat it proved difficult sometimes to get the boat floating as water rose. The rounded chines of the GU boats assisted this process and allowed the hull to free more easily, the vee bottom was supposed to help too. This was all down in a document I read at Stoke Bruerne 30 odd years ago and I can only presume was either a specification or minutes of a meeting re the building of the fleet. One can assume this still may exist in the E Port "black hole".

 

The other feature which the pairs had was the raised coming at the engine room doors, this again was seen on the Royalty boats, it was designed to limit the possibility of a passing wave getting in the engine room.

Edited October 31, 2012 by Laurence Hogg

[Chris Pink]

This was all down in a document I read at Stoke Bruerne 30 odd years ago and I can only presume was either a specification or minutes of a meeting re the building of the fleet. One can assume this still may exist in the E Port "black hole".

 

 

 

That would make for very interesting reading.

[Speedwheel]

(although the "Spice Boys" do seem to like to push their luck with Archimedes and Ara!!).

 

Which one of the 'Spice Boys' are you Mikey? I'm thinking 'Scary'.

[alan_fincher]

Which one of the 'Spice Boys' are you Mikey? I'm thinking 'Scary'.

Well which one of the Girls was "Victoria" !?!

 

Actually, I think Mike may be the not previously well known "Speedy Spice".

[Tuscan]

Well which one of the Girls was "Victoria" !?!

 

Actually, I think Mike may be the not previously well known "Speedy Spice".

 

 

AKA the Vicar.............

[Speedwheel]

Well which one of the Girls was "Victoria" !?!

 

Of course! I didn't think of that. Posh ..... on second thoughts .... maybe not.

[mykaskin]

Of course! I didn't think of that. Posh ..... on second thoughts .... maybe not.

 

Well, you don't get posher than royalty, so to speak...

 

Mike

[Hairy-Neil]

I suppose even the "Small" "Stars" represented a general increase in depth of hull-side over much of what went before, and I don't think were anything other than an attempt to come up with something slightly more modern, but still just a general carrying boat. They still tend to show considerably more freeboard loaded than say a FMC boat, don't they, (although the "Spice Boys" do seem to like to push their luck with Archimedes and Ara!!).

 

 

 

I recall reading a news item in Waterways World, perhaps 20 years ago, that Andy Boucher had loaded 27 tons of road planings on 'Cassiopia'. It was for a short haul run to Warwickshire Fly's, Stockton yard, though when I mentioned this tonnage to the 'Spice Boys' at the recent Alvecote rally they completely pooh-poohed the idea. I remember the photos at the time showed it to have far less freeboard than I've ever seen on Archimedes/Ara.

[mykaskin]

shows a star with only a day cabin and a HR2 (I think) moving 23 tons, another 5 inches (about 1 ton = 1 inch) would have had it sunk or on the bottom!

 

Add - if Cassiopeia had wooden bottoms, thats another 2 ton for the same draft I understand.

 

Mike

Edited November 2, 2012 by mykaskin