Stoker

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.

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!

Looking at what you've got there, I think you could get more "frontage" if you built your kiln angled around the curve, and used the turnout to form a coal stub instead.

Forgive the rather crude drawing, but this should roughly demonstrate what I mean:

7 hours ago, TrevorP1 said:

Thanks for the info on the China Clay wagons folks. All welcome. About the only thing I know for certain at the moment is that the ‘hood’ tarpaulins are far too late. I’m aware there were detail differences but not exactly what these were.

The Parkside wagon represents the 1913 GWR wagon dia O13. It seems the last examples were withdrawn in the late 1950s as they were replaced in batches by the new BR wagons. Some sources I've read say that they were all vacuum fitted by 1939, but I have photos from later with no evidence of vacuum hoses. Entirely possible that some remained unfitted to the bitter end or that the information is simply inaccurate, unfortunately I've got no reference material to verify. 

The main detail differences between the old GWR vs newer BR are angled vs straight bufferbeam ends, spoke instead of disc wheels, different axleboxes, and I believe subtly different brake gear although don't quote me on that as I'm far from being an expert. The hybar style tented sheets were added to this latter set of BR wagons in 1974 as a refresh in lieu of total replacement, and supposedly done to make the sheets easier to handle. So the ratio kit can make either the flat sheeted type introduced mid to late 50s or the hooded type '74-'87, while the Parkside kit would cap out at 1959.

40 minutes ago, St Enodoc said:

Stick with the Parksides Trevor. The Ratio ones, like the Bachmann RTR, have the roller-bearing axleboxes that are really too late for your (our) period.

The downside with the Parkside wagons are that they're simply too early, including the axleboxes which are a different type (albeit subtly) to the later ones. The ratio kit is the most accurate apart from the axleboxes, which are fairly easily removed using a sharp knife, and can then be replaced using Dart Castings RCH axlebox, a bargain at £4.20 for a pack of 12. https://www.dartcastings.co.uk/mjt/2241A.php

Dart also make a 12 pack of BR SKF roller bearings, which in addition to a wee strip of corrugated styrene at each end, is useful for converting RTR BR 5 plank opens to clayliners. https://www.dartcastings.co.uk/mjt/2256A.php

The Hewas Inn has always been a hidden gem in the area known for it's good food. Many clay area locals use it as the go-to "fancy restaurant".

Seeing the photos of your developing layout has given me the serious itch to draft some suggestions for fictional clay works. That back left corner in particular has good potential.

Many thanks to all who replied, this mystery has now been solved thanks to Ray Hill, who worked for the Goonvean and Rostowrack China Clay Co Ltd for most of his working life. This photo shows Ray at the helm of a Lansing Bagnall forklift within the linhay of the Trelavour dryer in 1971.

On 11/02/2020 at 13:54, TrevorP1 said:

I searched through my library and found the book with the Peter Gray colour photo featuring the bus and two panniers - Steam in Cornwall.  It is dated 13 July 1961 which was a Thursday. I've come to accept Peter's dates as accurate, especially so in this case as throughout the book there are a number of photos in the same area taken within a few days of this.

I took another look at the photo and realised that the linhay under construction is actually the Buell dryer linhay, and the rotary linhay appears complete. I had initially confused it with the construction of the rotary and it's linhays, which date to 1956. The Buell installation at Blackpool was of a pattern also constructed at Rocks, Drinnick, and Marsh Mills, all in the early 60s, which corresponds to Peter's date.

Here's a photo from 1962, the following year. Taken from Blackpool refinery on Burngullow common, looking down toward Blackpool. The rotary building is the one with steam rising on the left, containing 4 rotary units. The Buell building is the one with the steam rising on the right, containing 2 Buell units. The long row of linhays consisted of 13 bays and an attritor mill, with a total capacity of 20,800 tonnes. As you can see the silos have yet to be constructed:



This photo is the one I was thinking of, taken in 1956 during the construction of the rotary:



Blackpool was quite a complex. At it's height it was producing almost a third of the industry output, with the other two big producers being Rocks and Par.

Here's a look inside the rotary building, looking at No.3 and No.4 rotaries. No.1 and 2 were behind the cameraman. These big drums were about 7 feet in diameter and roughly 50 feet in length. The upside down "U" shaped things hanging on the frame over the conveyor belts at the bottom of the photo are horseshoe permanent magnets to catch stray metal. The filter press decks are on the left and right, these filtered the liquid slurry into a solid cake which could be dried. Each rotary unit had an output of approx 10 tons per hour, for a combined peak output of 40tph, enough to fill the entire linhay in 21 days.

I don't know if having a year would help at this point, Trevor, but the photo with the bus at Burngullow shows Blackpool dryers under construction, which occurred in 1956.

Just now, St Enodoc said:

I remember that Crinnis (Carlyon Bay) was exactly like that. Not much fun to walk on in bare feet.

Pentewan, Par, and Crinnis beaches all have a considerable amount of mining and streaming waste on them. Partly clay waste, partly mining. And yes it is rather sharp. The river that emerges from the cave in the cliff at Crinnis/Carlyon Bay is the same river that flows through Sandy Hill, and was used as a discharge by the mines of that area, and then later the clay industry. A lesser known fact of the mid Cornwall mining area, is that before Pentewan, Par, and Charlestown were used for clay export, they shipped tin and copper concentrate, and the local rivers ran red. Much of the early silting problems had little to do with the fledgling clay industry and more to do with the huge metal mines of the area, such as Polgooth, Great Crinnis, and Fowey Consols.

Just now, LBRJ said:

I believe it was the building of Par Harbour, or specifically the breakwater there, that dramatically increased the silting up of the estuary.

It is still pretty marshy around Par station now and there are several drainage streams - one of which comes out at the station car park and another is culverted  and runs along the boundary between St Bz yard and the adjacent St Blazey Road.

 

Par station is on Eastcliffe Road, which gives an idea of where the original coast line was, and it flowed around the bottom of the hill Kilhallon sits on upwards St Blazey Bridge (where the level crossing is on the Newquay line).

One would assume the Bridge was the first crossing point of the Par river, on  the "new" road of Tywardreath Highway.

 

The silting of Par came about 100 years before Treffry's harbour. The village itself was originally confined to what we now consider West Par, and grew up around Par Consols mine. After the construction of the harbour it spread out on to the flats of what was being called Par Green, which then was just fields, the earliest development being a single row of south facing cottages on the north side of the road, one of which later becoming The Welcome Home Inn. Par station stood isolated to the north, and originally served mainly the much larger community of Tywardreath to which it was closer. 

You are correct that Blazey Bridge on the road to Tywardreath Highway was the original crossing point. This is an extremely old road, medieval or older. The small settlement of Pontsmill was once a fairly busy 16th century port, capable of receiving 80 ton vessels as late as 1720, by which time the river had been reduced from two navigable forks to one by streaming and mining activity in the valley.

Quote

the 'white river' which flowed into the sea near Par

I remember in my youth when they were still white! There were a couple, but "THE" white river, aka the River Vinnick, flowed down from Gover and Trenance, through St Austell valley and out to Pentewan. The other originated from the great underground canal of Great Carclaze/Baal china clay works, down through Sandy Hill, emerging onto the beach of Carlyon Bay, which is partly why there's a beach there.

Did you know the entire village of Par sits on the silt from tin streaming waste which used to flow down the Luxulyan valley? That's why it's so flat. At one point it was a wide bay estuary which was navigable as far as Pontsmill.

Sorry, I'm going off topic with Cornish pub quiz trivia.

Trevor I'm looking at your photos and thinking that garage/MOT station or whatever it is looks a bit close to that embankment to my eyes. Just a suggestion, but if it were me I'd move it forward a touch so that you can have an earth bank rather than one of those awful retaining walls that too many modellers resort to (in my humble opinion).

On 28/12/2019 at 14:13, pb_devon said:

 

Hmmn, I’ve been to lunch in a pub with him, and left in a right state!!

Was he buying you pints of strong cider, by any chance? That's how he always got me hammered. Always thought he was going to the bar to get himself one, then he'd come back with two and put one on my beermat... felt rude to just leave it. Next thing you know you're on your way to the toilets, run your hand through your hair and realise you can no longer feel your scalp!!

Just now, Stubby47 said:

Thanks Stoker, but I have to say I don't want a china clay layout as such, hence my interest in the track plan north of the bridge.

I've added a fictitious 3rd siding,  to make up the inglenook,  but the higher, Drubbers siding could be used as the 3rd one, it would just stretch the layout somewhat.

To gain enough height for the bridge would need a steep incline out and also a falling line to the lower exit, but I think it would all fit in 8ft.

 

In Maurice Dart's West Cornwall Mineral Lines book, image 44 shows the last clay wagon leaving Drinnick Mill dries behind a Class 37.

I presume the loops between the photo location and the bridge were used to run around the wagon, which was then pushed under the bridge to let the loco lead up the incline towards the main.

Can anyone confirm or deny this assumption?

Operations at Nanpean Wharf were always awkward. There was a loop just south of where the line down to the Wharf diverged from the branch. This loop was used for Dubbers and West Of England sidings, and could provide a run around for the wharf, but trains were limited in length by the wharf forming a considerable chunk of the headshunt. If wagons were present at the wharf when a train had to run down to the lower lines, those wagons would have to be removed to the branch before the train could proceed. This was further compounded by the loop at some point being truncated into a siding removing it's functionality, meaning that the lower level sidings were only accessible as a propelled reversal from the wharf. Trains leaving the lower level sidings would have to run the locomotive around the wagons and propel the train up to the wharf in order for the locomotive to be on the correct end of the train if it was travelling back toward Burngullow. More often than not though, train movements at Drinnick were scheduled to take place as part of other workings up the branch, meaning the train could be propelled back up the incline toward the branch to rejoin part of a longer train as it worked toward Treviscoe or Parkandillack.

Just now, Rhysb said:

Thanks for the feedback guys. I wanted to lay the slaters sheet on boards as close to the real thing to try and create proper definition and be as real as possible.  
 

On the photo you can really see the individual sheets of cladding:

 

I know this building, it's Treviscoe rotary. The large structure in front is the linhay, the smaller structure with the almost white roof in behind it is the dryer. Notice how although the panel gaps are visible on the structure in the foreground, they are invisible on the newer roof in the background. The photo is a low resolution zoom of a drone image, but I strongly suspect the reason the panel lines are so visible is due to moss growing in the gaps. The same thing happened to Parkandillack New Buell:



You can see how on some parts of the roof the panel lines are nearly invisible, while in other areas they're highlighted by moss and weather staining.

Tom Johnson has proven very well that the effect can be created entirely with weathering on his HO scale Logansport and Indiana Northern layout.



This building is a completely unmodified Walthers Cornerstone kit (I know because I own the same kit) and the only physical panel lines it has are the horizontal. The illusion of individual panels and vertical laps was created by Tom's process of weathering each panel individually before going on to the next, and highlighting the joints with a carefully applied pinwash.

If you're interested I have a track plan for a layout based on the low level lines. It's slightly condensed to retain the linhay on the right and rail overbridge on the left as scenic breaks without taking up too much space, and having the added operational interest of the power plant coal chute. Designed to fit on an 8ft x 2ft plywood, using Peco EM gauge Bullhead as a good standard for realistic curves and turnout lengths. I also have a "close enough" mockup of the building in sketchup.

Just now, LBRJ said:

That is the way I would ( and have occasionally) laid model corrugated sheets; and I have laid/mended more than a few of the real thing over the years.

To my eyes, the overlap on side by side sheets is barely visible at full size*, but something like half an inch maybe at the top/bottom over lap.

 

*on some older, mossy roofs one has to look quite carefully for the join, just to make sure you are attacking the right sheet to start with - I know this well  

Agreed, it really isn't visible at distance. Far more noticeable is colour variation of sheets and gaps, where differing materials and weather occlusion create natural highlights.

The method for corrugated roofing that I've used with great success is to cover the entire roof in styrene sheet to provide a gluing surface, then cut the corrugated sheet into strips of the desired size and glue them onto the styrene sheet. Then above each strip lay a thin strip of styrene to bolster the bottom end of the next strip so as to create a visible lap.
 

This example is a HO scale grain elevator and feed mill complex that I've had on the back burner for a while:



Although I've never tried it, I believe it would be quite possible to use this method to create the lap between individual sheets. I've never bothered, choosing instead to create the effect using weathering.

7 hours ago, TrevorP1 said:

The Burngullow West kiln certainly looks interesting - to think of the number of times I've driven past that and didn't know exactly what was there, although the chimney is quite familiar of course. When I began thinking about my slight change of direction I bought a copy of Maurice Dart's book 'West Cornwall Mineral Railways' and spotted the photo of the Carrancarrow Kiln at Trenance just east of Burngullow. Measured from the National Library of Scotland website Carrancarrow is 250'. One of the Bradford Barton books has a photo by Brian Butt of the Cornish Riviera passing this spot.

 

At an appropriate point I'll play around with some card mock-ups to see how things look. I'm hoping that I'll be able to suggest that there is more beyond the building(s) that will actually be on the layout. 

There's always the option of doing half relief.

If you like when the time comes to figure out this aspect I could mock up a couple of 3D models for your consideration. I'd just need a basic idea of the trackplan and the available footprint for structures.

Also probably worth mentioning that I have modelled several prototype and fictional linhays, drys, and other related structures in Google Sketchup Make 2017, which is an easy to use 3D software available for free download online. If you are interested in these models for research purposes, I can email the model files upon request.

Just now, TrevorP1 said:

Thank you for those @Stoker . The ply for the new baseboard tops arrived yesterday so I've been able to make a start today. Funnily enough I was trying to imagine the linhay whilst I was working. 

 

I was more thinking along the lines of an old style kiln but nothing is settled yet - far from it! One thing that is settled is that I want to do it properly. I'm aware of the information you have kindly put up and have spent some time studying it. I will most likely wait until least the late summer after I've made  another visit to Wheal Martyn. 

 

Good luck with changes in your life by the way. All that space - inside and out!

The old coal fired pan kilns have the major disadvantage of being long, averaging around 250' to 300'. I only ever encountered one rail served prototype of "layout size" at Burngullow West, which may be of particular interest given it's location. It's actually still extant in remarkably good condition complete with piles of clay, despite about 50 years of abandonment. It shared the rather grand square chimney with the neighbouring kiln. I conducted a survey of the building before I left the UK and have attached scale drawings.

Also attached and possibly of interest, is Burngullow West's bag store, a standalone building which apparently received clay via blondin from the dry opposite. This structure is visible on the right hand side in most photos taken from the bridge next to Burngullow station, looking toward the St Dennis branch where it diverges from the mainline.

Rhys, somewhat off topic, but I can't help but notice your company is using the wrong type of Kaolin. Kaopolite SF is an abrasive grade normally used in the manufacture of toothpaste and polish, and is manufactured in Sandersville, Georgia, USA (read: higher shipping costs). Correct me if I'm wrong but I suspect your company is attempting to use the product as an opacifier. The product you probably want is Imerys Opacilite, which is manufactured in Cornwall, and will produce far superior results. Likely worth bringing it to the attention of your bosses as I suspect they're probably just buying this stuff from a distributor/supplier without realizing.

On 26/01/2020 at 11:38, TrevorP1 said:

As far as the clay dries go they obviously cannot be as large as even a small 'real' dry  but they will be large enough to make a nice set piece I think. The letters are nothing to do with the railway as such just part of my baseboard cutting list.

You say that, but 700mm scales out to 175', there were several bulk store type linhays (fed by conveyor belt) from your chosen period that were around that size or smaller.



(Above) Kernick Buell bulk store, built 1951, fed by the first oil fired Buell type dryer built by the industry, it's square concrete stack visible in the background: 100' x 80' with a 13' awning covering 3' deep loading edge and 10' over track, later extended with an additional 80' x 60' section. Loading edge height 7ft above railhead.



(Above) Rockhill bulk store and baghouse, built 1939 and the first of it's kind to be built in Cornwall, the taller structure on the right, fed by conveyor bridge from the small rotary drying plant in the buildings behind the old linhay on the left. Served by the Goonbarrow branch and the last source of traffic from there in 1978. 100' x 60' with a 13' awning covering 3' deep loading edge and 10' over track. Loading edge height 4ft above railhead (vans).



(Above) Drinnick No.5 bulk store, built 1951, fed by the rotary dryer housed in the building on the right. 175' x 95' with a 13' awning covering 3' deep loading edge and 10' over track. Loading edge 6ft6in above railhead.

Will be watching this with interest, for obvious reasons. Par is probably my favourite station, period. Many, many fond memories of that spot and St Blazey, evenings well rounded off with a stop in one of the many local pubs.

2 hours ago, pb_devon said:

And do I spot Maurice in the group?!

Yep that's Maurice. I think we wound up taking him to the William Cookworthy pub after this for some lunch.