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China clay loading?


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I am currently in the process of building a small N scale 80s/90s China Clay layout, what I am trying to find out is how the different types of China Clay are loaded and which vehicles are used? Any pictures, information, links, books etc that can be provided would be excellent!

 

I am currently awaiting for the arrival of "Cornish China Clay Trains in Colour" by Maurice Dart. Hopefully this will yield some additional information!

 

I also had an issue of Model Rail which had a China Clay feature in, sadly I binned it. Does anyone one know which issue it was? I think it was around 2000/1.

 

Many Thanks,

 

Jack

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Try 'An Illustrated History of West Country China Clay Trains' - John Vaughan (OPC, 2nd edn 1999 ISBN 0-86093-543-4).

 

OOP, but still common enough second hand.

 

Cheers for that tip, found one on Amazon used for £5.95 which is now winding its way to me. I find amazon is very good for secondhand and new books, it's surprising some of the obscure and rare books they and their market place sellers stock.

 

Regards,

 

Jack

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China clay in its rawist form is washed out of the granite landscape by high pressure water hoses. The resulting slurry is than allowed to run to lakes/settling tanks where some is loaded as slurry (Shipped in the silver bullets) and then most is dried and loaded as a white powder into a variety of wagons.

 

On local services the old vacuum wooden bodied clay hoods were in use during the early/mid 80's where they were replaced by the CDA's hoppers that are in use today.

CDA's

 

Traffic to Stoke-on-Trent went over to airbraked Tiger Polybulk hoppers during the 1980's (Sorry I don't have any images available in the computer formats available at the moment as i've not got round to scanning them yet)

 

More recently it has been moved to Stoke-on-Trent (Cliffe Vale) by these wagons

Claywagons

6M72 St Balzey-Cliffe Vale

6M72

 

Hope this helps

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China clay in its rawist form is washed out of the granite landscape by high pressure water hoses. The resulting slurry is than allowed to run to lakes/settling tanks where some is loaded as slurry (Shipped in the silver bullets) and then most is dried and loaded as a white powder into a variety of wagons.

 

On local services the old vacuum wooden bodied clay hoods were in use during the early/mid 80's where they were replaced by the CDA's hoppers that are in use today.

CDA's

 

Traffic to Stoke-on-Trent went over to airbraked Tiger Polybulk hoppers during the 1980's (Sorry I don't have any images available in the computer formats available at the moment as i've not got round to scanning them yet)

 

More recently it has been moved to Stoke-on-Trent (Cliffe Vale) by these wagons

Claywagons

6M72 St Balzey-Cliffe Vale

6M72

 

Hope this helps

 

Thanks for the reply!

 

How is the powder stored, is it stored in silos and discharged by hose into the wagons, or do they use a conveyor belt type loader? I have some sheets of corrugated iron that I hoping to build some structures from, I have found photographs of several china clay buildings however it is difficult to ascertain how each one is used and what loading kit is hiding under the roofs.

 

I have also seen what look like the type of concrete pools you'd get at a sewage treatment plant, are these the settling tanks?

 

Regards,

 

Jack

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Hi Jack

 

The dried powder form china clay used to be shovelled by hand into the wagons, nowadays it's done with a mechanical digger. The clay loading "linhays" had open doors from where the loading was done. Take a look at Andrew "ullyug" Ulliot's Wheal Elizabeth building for a nicely modelled version http://www.rmweb.co.uk/community/index.php/topic/3297-wheal-elizabeth/page__hl__wheal%20elizabeth__fromsearch__1

More modern loading plants are now are enclosed to avoid the loads getting wet - looking like any nondescript metal cladding industrial shed.

The settling tanks are as you think, used for separating the water from the material.

Some traffic is/was in the form of slurry ie the undried form - this was simply piped into the wagons. The "Silver Bullet" wagons which Dapol are now producing are the sort of wagon used for this traffic.

Hope this helps.

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It;s been along time since I went to a China clay quarry (about 1983) but they used to load the open wagons and the the tiger wagons with a Shovel Loader (Big front bucketed digger that weighed as it loaded). It can be stored in silos, as its like any powder it can be stored in a number of ways. Best way to view it is like white cement)

 

from what I remember the settling tanks do look like big sewage works and once all the water has run off the semi-slurry (china clay) is then taken to the dries, where they are baked at vast temperatures to produce the white powder.

 

It's 27 years ago that I studied geology and went to various clay pits whilst on field trip, so forgive my vagueness. In fact I'm sure that there was a discussion about the best way to move china clay slurry but can't remember the context of it. I was 17 and there were more important things than listening to talks of china clay.

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Thanks for the replies,

 

So am I aiming to have warehouse which the wagons are to propelled into, inside being a bucket loader and several mounds of clay powder? Or are they the same structure as the one in operation on Wheal Elizabeth, only with a bucket loader inside?

 

Wheal Elizabeth is beautiful layout, I hope to get to a show it see it in the flesh!

 

Regards,

 

Jack

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I suggest joining the China Clay yahoo group. It is pretty quiet so you will not get your inbox flooded but the members are friendly and helpful. Plus there is a wealth of photos on the site from the steam era right up to the present which will come in very handy.

 

Come and join us here. :)

 

http://groups.yahoo.com/group/china_clay_branchlines/

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So am I aiming to have warehouse which the wagons are to propelled into, inside being a bucket loader and several mounds of clay powder? Or are they the same structure as the one in operation on Wheal Elizabeth, only with a bucket loader inside?

That is a tricky question as the dates you are modelling represented a big shift in china clay transportation. The mid-80s saw the final demise of the clay-hoods with their manual loading. At the start of the period you are modelling, some dries had barely changed from the steam age which is why Wheal Elizabeth can run in anything from the 60s to the 80s. By the 90s china clay was a modern bulk transported commodity with the old clay dries relegated to history.

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[quote name='Rods_of_Revolution

 

I also had an issue of Model Rail which had a China Clay feature in, sadly I binned it. Does anyone one know which issue it was? I think it was around 2000/1

November and December 2000 had the china clay articles. November covered up to the 1970s, December the more modern.

Rail Express Modeller No. 5, inside Rail Express No. 100 has a 'Modellers guide to china clay services' which includes suggested track plans for two loading points.

Rob

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Right, I've applied to join the Yahoo Group and also purchased the issues of Model Rail on eBay. Cheers for all the help and information, it's brilliant!

 

I think a more modern China Clay facility is what I'm after, I hope to expand my rolling stock towards the present day. I love the 37s especially in the RFD Grey and weathered accordingly, but I'm sure I'll visit Cornwall in the near future and want to supplement the stocklist with a shed or two (even though I just sold one!) for a 90s/00s era. Though I suppose modelling today would be a 00/10 era?? how time flies!

 

Kindest Regards,

 

Jack

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Merged with existing topic from just a week ago - and easily found on the search facility.

 

Cheers.

 

I like the way someone always says "easily found". I guess it is easy if you know what to search for and where to look. I have searched for "china clay" and am unable to find the merged topic this refers to. Can anyone help?

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Dried China Clay was often but not always handled loose, either by man and shovel or by mechanical grab. Some was bagged and transported in 4-wheel vans. IIRC there were even a few of those stencilled "Bagged China Clay Only" or something similar.

 

A variant on the regular product was "ball clay", very similar (it's still Kaolin) but recovered, as the name suggests, in rounded nodules typically about cricket-ball size. Some open / hood wagons were reserved specifically for this traffic and were accordingly stencilled "Ball Clay Only". That was to ensure the two products did not become accidentally mixed in the trans-shipment process. The large Cornish pits produced most of the dried / powdered china clay and slurry while ball clay mostly came from the pits farther east around Lee Moor and Bovey Tracey. The difference between the two regions and the form of their mineral deposits lies in their geological history being very slightly different.

 

Bachmann have released OO ball clay hoods at times; I seem to recall they are the ones with the yellow stripe around the hood though I'm willing to be corrected on that.

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I like the way someone always says "easily found". I guess it is easy if you know what to search for and where to look. I have searched for "china clay" and am unable to find the merged topic this refers to. Can anyone help?

 

It's merged into this one now as stated by Mod2 so it won't exist as a separate topic.

 

For future reference, I think the search facility is still a bit hit and miss, but the 'advanced' option (link to the right of the search button top right) is more powerful, or try via Google specifying RMWeb.

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The large Cornish pits produced most of the dried / powdered china clay and slurry while ball clay mostly came from the pits farther east around Lee Moor and Bovey Tracey. The difference between the two regions and the form of their mineral deposits lies in their geological history being very slightly different.

Not so. The geology of the Lee Moor area and the kaolinisation is exactly the same as that in Cornwall - Lee Moor produces white kaolin in the same manner as in the Cornish Pits. The geology is different - kaolin is produced from feldspars and is a hydrothermal process - kaolinised granite is soft and water is needed to separate the kaoloin from quartz and mica. This occurred whilst the rock was still hot and waters still flowing during the mineralisation phases. This was occurring between 300 and 270 Ma (million years)

 

The Bovey ball clay is a Tertiary age sedimentary deposit in a complex basin associated with the Sticklepath fault. There are also deposits in the Petrockstowe Basin, adjacent to the same fault line. The maps give this age as 35 - 23Ma. Ball clay is shoveled, not washed out.

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There was a good oo model of Blackpool dries in RM a few years back and indeed it depicted the idea of cdas being loaded by the bucket of a cat type shovel. It had some nice cameos including a little chap with an air tool cranking open a cda cover

 

I can't find my copy but seem to recall it was made by a chap for his grandchildren

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Not so. The geology of the Lee Moor area and the kaolinisation is exactly the same as that in Cornwall - Lee Moor produces white kaolin in the same manner as in the Cornish Pits. The geology is different - kaolin is produced from feldspars and is a hydrothermal process - kaolinised granite is soft and water is needed to separate the kaoloin from quartz and mica. This occurred whilst the rock was still hot and waters still flowing during the mineralisation phases. This was occurring between 300 and 270 Ma (million years)

 

The Bovey ball clay is a Tertiary age sedimentary deposit in a complex basin associated with the Sticklepath fault. There are also deposits in the Petrockstowe Basin, adjacent to the same fault line. The maps give this age as 35 - 23Ma. Ball clay is shoveled, not washed out.

There are further ball-clay deposits in the Torrington area, and also near Wareham- the latter rail-served into the late 1980s. The ceramics industry probably uses far more ball-clay than china-clay- the latter is used mainly in the production of fine china and glazes, whilst ball-clay is used for earthenware.

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There are further ball-clay deposits in the Torrington area,

 

Yes, that's the Petrockstowe Basin deposit.

 

and also near Wareham- the latter rail-served into the late 1980s. The ceramics industry probably uses far more ball-clay than china-clay- the latter is used mainly in the production of fine china and glazes, whilst ball-clay is used for earthenware.

 

The Wareham deposit is geologically much earlier than the Bovey/Petrockstowe, at about 45Ma. the deposition environment has rendered them different chemically with different colours and properties.

 

There's a lot of information about formation and commercial exploitation here - http://www.clayherit...es/deposits.htm

 

References:

Durrance, E.M. and Lamming, D.J.C. (eds) (1982) The Geology of Devon. Exter: University of Exeter.

Edmonds, E.A, et al (1975) British Regional Geology South West England. London: HMSO.

The Ball Clay Heritage Society (2010) Online: http://www.clayherit...es/bchspage.htm [Accessed 6 April 2010]

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