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Porthleven - Cornish Harbour & China Clay Circa 1990


Rhysb
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8 hours ago, Stoker said:

Looks about right for one of the smaller stores. You may be interested to know the small one at Kernick, on which the scalescenes was based, was originally half the size, it was doubled in I think the mid 60s. There was also a really tiny linhay on the Goonbarrow branch which I think was only about 100 feet or so in length. It was fed by ECC's 1939 vintage Rockhill rotary dryer. Fun fact, during the 1978 coal strikes, Rockhill was prepped to dry peat from Bodmin Moor to fuel Drinnick power plant!

Thanks Stoker.

 

This is about 1040mm long. So about 260ft in real life.

 

Rhys

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16 hours ago, Stubby47 said:

Apologies - tangential posting.

 

@Stoker presumably there were inbound coal wagons / trains to each of the dries, something not often modelled. How much coal would be needed to run an average size plant?

Stu

 

It depended on the size of the dry, but a very simple calculation can be done. 1 short ton of coal will boil 10 tons of water. Clay to be dried was about 20% moisture, so for every 5 tons of wet clay 1 ton of that was water. Most coal fired drys were producing 2.5 tons per hour, so that's 1/20th of a ton of coal, or 100lbs an hour. That's a reasonable rate of shoveling considering the furnace had to be fired by the same men who shovelled dry clay off the pan.

 

So your answer would be somewhere around 30 tons a month.

 

After about 1950 ECC mostly trucked their coal from Par harbour to the dries, putting an end to coal by rail, except in cases of distant dries such as those around Bodmin Moor. They continued to receive coal by rail until they were updated to oil fired mechanical dryers.

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10 hours ago, Stoker said:

 

It depended on the size of the dry, but a very simple calculation can be done. 1 short ton of coal will boil 10 tons of water. Clay to be dried was about 20% moisture, so for every 5 tons of wet clay 1 ton of that was water. Most coal fired drys were producing 2.5 tons per hour, so that's 1/20th of a ton of coal, or 100lbs an hour. That's a reasonable rate of shoveling considering the furnace had to be fired by the same men who shovelled dry clay off the pan.

 

So your answer would be somewhere around 30 tons a month.

 

After about 1950 ECC mostly trucked their coal from Par harbour to the dries, putting an end to coal by rail, except in cases of distant dries such as those around Bodmin Moor. They continued to receive coal by rail until they were updated to oil fired mechanical dryers.

So by the early 1990’s when This layout is based I am guessing on your information that the dry would be oil fired? 

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On 16/06/2020 at 03:51, Rhysb said:

So by the early 1990’s when This layout is based I am guessing on your information that the dry would be oil fired? 


In the early 1990's only two coal fired drys remained; Great Wheal Prosper dry at Carbis Wharf, and another (not rail served) deep in the west near St Just. By that time, manual labour had almost completely been eliminated from the once dreaded "old way". Mechanical stokers fed the furnaces (a circa 30's to 50's innovation), a filter press house replaced the wagon tanks (these came in early 1900s), and the role of men shovelling dry clay off the pan was replaced by a small kubota excavator which rode on one of the two travelling bridges (introduced around the 1980s).

Lord Falmouth's "underdog" clay company Goonvean & Rostowrack owned "Prosper" dry, and leased a single Tiger wagon from the fleet that Tiger had originally allocated entirely to ECC. I believe this ended up being the last white tiger, the last freight out of Carbis, and the only air braked wagon to receive clay dried by coal.

A photo of the mechanical stoker at Great Wheal Prosper dry, Carbis. Coal came in down the chute into a small hopper, which fed into the tube seen below. The tube contained a spiral auger which fed the coal into a "bowl" hearth a bit like a giant tobacco pipe. Air was blown into the furnace via the square duct:

2099062029_carbiscoalstoker.jpg.c75b8dbd1b5b680a417308336efa1b1f.jpg

The photo below shows the filter presses at Carbis. These brought clay slurry pumped at pressure from the tanks into the bank of cast iron plates which were lined with filter cloths. Clay would then build up on the cloth eventually forming a giant 4ft square cake weighing about 200lbs. As you can see from the spatter on the roof, sometimes the cast iron plates would "give up" under pressure, which made a terrible mess.

presses.jpg.a9cdb155a910e44364bdc7f492321ec8.jpg

Here we see the Kubota KH-31 that was used at Prosper on the pan. It has it's own heavily reinforced travelling bridge, which it was able to move itself along on using the arm. This machine was used to break up and distribute fresh filter cakes across the pan, and also to remove dry cakes to the linhay.

737024276_carbiskubota.jpg.38c31d9f938594e481b9ccdc42665181.jpg

Lastly, we have the tram wagons on the other travelling bridge, which were used to carry the filter cakes from the press house to the desired spot on the pan. As you can see they were side-tipping.

tramwagons.jpg.a3b11cd81990e90c2b7b10964d05408c.jpg

Early oil fired mechanical dryers built between 1939 to around the early 50s were all built as an extension onto the original coal fired dry, which itself was usually modified by the internal removal of the redundant "pan"  and installation of conveyor belts to carry dried clay through it. ECC's first "big" modern conveyor fed linhay was built on Par harbour around 1951, and was a second hand derigible hangar from RAF Davidstow. The company installed a pair of large rotary peanut roasters inside, and set them up to dry china clay. After just a couple years the plant at Par proved a success, and so the company shifted from mechanizing old dryers to building entirely new plants. The vast majority of coal fired dryers were shut down during this period as they were replaced by huge new plants capable of orders of magnitude higher output.

Here's a photo of the linhay in question at Par in 1951, former RAF hangar of truss construction, being assembled around the pair of peanut roasters:

87857365_2578293709154950_632632829976510464_n.jpg.4316b3c0ba0f36f90810bb54ea5e7a1b.jpg

A closer photo of the peanut roasters sat on their giant concrete plinth:

88162007_2578293672488287_3721568447356731392_n.jpg.037532ad0681a2a20da5a5e441b98928.jpg

Edited by Stoker
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  • 2 weeks later...
On 17/06/2020 at 12:50, Stoker said:


In the early 1990's only two coal fired drys remained; Great Wheal Prosper dry at Carbis Wharf, and another (not rail served) deep in the west near St Just. 

 

 

 

Just a bit of history on the latter one in your post but the St just site was Lower Bostraze and it reopened in the 1960's and used a oil fired kiln till its closure in 1991 when it was deemed not cost effective.

 

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Just now, Cornish_Rail said:

 

 

Just a bit of history on the latter one in your post but the St just site was Lower Bostraze and it reopened in the 1960's and used a oil fired kiln till its closure in 1991 when it was deemed not cost effective.

 


Yes you're right it was oil fired, I forget about that, so technically not a coal fired kiln although still a traditional pan kiln in every other respect, and you're correct that it closed in 1991. The heat from the oil burner passed through the old furnace and under the pan, which dried the clay in the traditional way without any mechanical assistance (apart from the digger). Quite remarkably, the works was operated by English China Clays, and was the last pan type dryer the company operated. It's quite incredible to think that this dinosaur outlived the technically more modern 1939 built Rockhill rotary, and ww2 built Collins rotary and Drinnick Old Cooperage Buell.

lowerbostraze.jpg.9fc6532155e70b46ddbbd4bc4fa25ef8.jpg

This photo taken in 1992 one year after closure shows Lower Bostraze dry from outside with it's distinctive square brick stack, the settling tanks are also visible. The equipment on the left resembling shelves are triple deck screens, very outdated by the time this photo was taken, but in the 30's through to the 60's these were quite commonly used to classify clay to the desired particle size distribution prior the use of more sophisticated refining plant such as centrifuges, floatation cells, hydrocyclones, and hydroclassifiers. Lower Bostraze was not within pumping distance of a clay refinery, and it's 5000 ton per annum output precluded building one locally, so it had to use this more primitive method to the bitter end. If these were not used, there was no way to separate coarse from fine grade clay, and also some clay would be so fine that it could actually pass through the filter press cloth and be lost in the filtrate. This undersized clay was pumped back to a tank where it would be dosed with a chemical called a flocculant, which encouraged the clay to form into larger particles, and then pumped back through the screens to form a closed circuit.

34246-Lower-Bostraze-lg.jpg.5dbd725c8ca23ad5b644b06fe2d6567e.jpg

This CCHS photo on the interior of Lower Bostraze shows the small digger used to move dried clay from the pan to the linhay. The travelling bridge with wagon can be seen being moved by a worker, and I believe the item on the wagon is a quick-attach implement of some kind.

bostrazefurnace.jpg.fb80b2cf283a442453172ecfdb317b27.jpg

This photo, credit to Jim Casley son of the last manager of the works, shows the oil burners in the furnace.
 

Edited by Stoker
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I have just had a catch up with this interesting layout build. The additional information of the china clay industry being shared is also interesting.

 

I do love the weathering on the CDAs, as a former TOPS clerk (used to receiving wrong wagon numbers) I would think that the number and data panels would be kept clean(er), though I notice you have done this on at least one CDA,

 

cheers

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21 hours ago, Rivercider said:

 as a former TOPS clerk (used to receiving wrong wagon numbers)

:D "Those 24 tipplers that arrived loaded on Tuesday, have just departed back to East Depot"

"What tipplers were those?"

"I dont know the numbers, its those that arrived on Tuesday"

:lol_mini:

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  • 4 months later...

Morning Bill, Morning All,

 

Well a huge amount of progress is something that has not been made! Lockdown and a golfing summer and the realistic notion that it may be some years before I can take Porthleven out on the road has led to it being placed on the back foot a little. I certainly have not stopped but I have been playing a bit with Leighford (my NSE layout) and scratch building some buildings for the harbour at Porthleven.

 

However for all you Cornwall/China Clay lovers I have also been working on/planning something big to be revealed soon... All I will say is think Penhayle bay... just a tad bigger ;-)

 

Anyway onto Porthleven I have over the summer got the linhay to some sort of completion. I needed to get this done to complete the track in this area. Its just details to do now. A bit more weathering to the roof and with the inks on the printed sections discolouring a bit of plasticard cladding is needed!

 

An overall view of the Linhay:

Linhay1.jpg.3e7b7d0abc5a571511b2a8e82b33da90.jpg

 

The track plan into the Linhay and front area is completed

Linhay2.jpg.a01e6b39db6320299312e12e995579f0.jpg

 

Its not the biggest Linhay in terms of real size but its big in model form:

Linhay3.jpg.25a7c6f8a706515edd176bf433477e02.jpg

 

As you can see the card/printed elements have discoloured slightly:

Linhay4.jpg.189a2289570db9fd7e6dce6c0903db0a.jpg

 

Linhay6.jpg.b5264f1e87438674a01461765c17c71f.jpg

 

Finally a bit of scratch building underway... This is going to be my "rendition" of the Ship Inn on the harbour wall:

1420190034_ShipInn1.jpg.15ef8ccb5f3c9a14361ea79310e7b2f3.jpg

 

And the real one for good measure:

505339019_ShipInn4.png.8d0ec220e6b0b3bfe411b063ddc53685.png

 

Hope to see you all soon, stay safe

 

 

 

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  • 6 months later...

Well months later, another lockdown but my word summer has finally arrived! So with summer arriving I decided to head from Somerset down to Cornwall to go to the pub.... well not in reality but in OO world! Plus I needed to build the pub!

 

With Summer here and recent trip to Cornwall for my stag do! My juices were flowing to get Porthleven moving.

 

So onto the pub! As I’m using Porthleven as a inspiration I want to copy/replicate/bodge as many buildings as possible. The first is the iconic Ship Inn at the end of the outer harbour/breakwater.

3336A3E8-4090-4850-8C36-948D95F82A97.jpeg.29f92b7d15f9e78cd446d245067b6205.jpeg

 

F4F1CD50-8523-4114-83CC-9ED641CC8E72.jpeg.26e8e9cf0eabc62008cf7a73e5e8fd57.jpeg

 

07EDB035-C630-4B2E-9DE0-129D2B521B96.jpeg.f21854ae0b19e38fe4169f7d3f4e3173.jpeg

 

DB9F499F-F07B-4E78-8239-C78E9DA9AAA9.jpeg.9c1a636eb0f3b896e79e4f77dca0e0a7.jpeg

 

 

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The pub looks great. 

 

What did you use for the wall render, it is very effective.

 

Just one minor comment, in the close up photo of the end wall, the chimney stonework is very smooth when compared to the walls. It may not be so noticeable at a distance, but something to consider.

 

Hope you find the comments useful.

 

Regards 

 

Nick 

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4 hours ago, Stubby47 said:

Is the pub missing a couple of chimneys ?

Your missing the words... inspired by/copy/replicate/bodge ;)

 

Its always a compromise as while I want to get as close as possible im still using doors/windows etc from kits or parts.

 

Thanks

 

Rhys

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4 hours ago, stivesnick said:

The pub looks great. 

 

What did you use for the wall render, it is very effective.

 

Just one minor comment, in the close up photo of the end wall, the chimney stonework is very smooth when compared to the walls. It may not be so noticeable at a distance, but something to consider.

 

Hope you find the comments useful.

 

Regards 

 

Nick 

Nick,

 

Its Vallejo textured paint. Think its called white stone

 

Thanks

 

Rhys

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Lovely work Rhys, although one suggestion if I may... looking at the prototype and your model, I believe the pub would greatly benefit from the addition of some window sills! 

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  • 3 weeks later...

So this beast was back on the workbench tonight!

00ADD802-729E-4C3C-9EE7-84A5E254EB2D.jpeg.c3db7337086a36bf7860c653ecba1b9d.jpeg

 

Apart from the roofing I used printed sheets to clad the lower part of the building and despite loads of varnish they have over time turned from a grey to a funny pink colour.

 

So time to do it right and clad it with plasticard sheets. Also wanted to add some more details.

 

You can see the difference:

8CD625AD-0A6D-43B6-9DB8-B910E09E30C8.jpeg.cef67cd9be235e2fedd2628a963f44cc.jpeg

 

Plus wanted to add some structure to the building with some I and H beams which I will weather down. Here is the idea:

DA71DE1B-BE9E-4E13-ABBE-9757D0BEBACB.jpeg.989c47a0782259adbe20defaf8d2f93a.jpeg

 

more to follow!

 

Thanks Rhys.

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