Making rock cliff cuttings from plasterboard.

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While renovating my garage I used a substantial amount of plasterboard which I had initially intended to chuck, but was advised strongly against doing at the time by my father in law who cited various DIY projects where it could be used.  Time passed and it still sits there or did until about a month ago.  I have been doing a fair amount scenery building with plaster and it dawned on me that the same brick/rock effect would obviously be available from plaster on plaster board as it would on plaster.  I have a fair amount of rock cuttings to do and thought that as many of them would be cuttings as opposed to cliffs that I could use the plasterboard to make these.  These plasterboard cuttings can only authentically be used to replicate dynamite blasted rock strata as natural rock strata is never vertical or as clean cut as these would appear when finished.  However as these cuttings are fairly common in real life railways there is plenty of scope for using up a fair amount of the plasterboard cluttering my garage.  Naturally eroded rock cliffs tend to weather along fault lines determined by the crystalline structure of the rock and tend to be more three dimensional.  When cuttings are blasted normally long parallel lines are drilled into the rock which are then filled with explosive charges.  These are then detonated simultaneously and the remaining surface is relatively even.


Example of a cutting.  Unfortunately good railway ones were a bit harder to find on the net.


This one was a railway one but is disused and now over grown.

The plasterboard modelling process is pretty straightforward.  I would recommend doing this outside and over a bin if you can.  You may wish to use a mask and goggles as this is very messy.


The section of plasterboard cut to size.


Insert stanley knife or screwdriver between the card covers into the plasterboard.  


Prise away the plaster on one side.


Continue to remove all of the paper from one side of the plasterboard leaving the other to maintain structural integrity.  I initially used a screwdriver but this is incredibly slow and found a Stanley knife far quicker.  By wedging the knife in the side and twisting a shattered rock effect can be gained while removing the paper.  Once all the paper is removed from one side you can use a screwdriver to add more effects to make it look more like shattered rock.



Once the paper is removed, a series of coloured washes can then be applied to resemble the rock of your choice.  For the first coat I used a matt enamel type paint diluted with turps to seal the plaster. The colour to choose depends on what type of rock you are after, white for chalk, grey for Oolitic Limestone, beige for Portland Limestone, red for Central Scottish sandstone. You really don’t want any dust getting onto the tracks or into the inner workings of your locos.  For subsequent coats you can weather the rock face or add other colouring to resemble the type of rock you are trying to represent, e.g. spots of pinks or whites for granites.


This is the sheet when placed in position on a slope.  If you are using water based stains for the secondary coats it is best to do this on a warm day or in a heated room as you want the plaster to dry quickly and not absorb the water.  I tend to use several layers of washes to build up the weathered look.  I have a large container of stain wash which I apply every time I am out there to build up the layers.




Under construction.  I used Siliflor pasture for grass as it gives a good Swiss Alp sort of look.




Some of the grass tufts from International Models too are good as weeds on the cliff face.


BTW, the panel at the back of the tunnel isn't flush as it has to be removable so that I can adjust the electrical wiring for the S-88s when I change the length of the loco on the shuttle lines.


Almost done.  I will continue to apply washes over time to get a better weathered look.  The cows seem ok with it though!

Plasterboard would also be ideal for making brick walls too however once you have removed the surface paper lining you will have to level the surface again by sanding it flat.  It may be easier to apply plaster to the surface you intend to look like wall than to do this however it does offer one major advantage; it is difficult to line and etch the plastered surface while it is attached to a structure on your layout.  It is comparatively easy to work with a sheet of a foot or so of plasterboard and to etch lines into it with a modelling knife and steel rule.  There is also the ability to “point” the brickwork which is best done on a flat surface.

 Here's some pictures from another one that I am working on.  This one is a bit bigger.



This one is quite large and although the panels come from the same sheet of plasterboard they have to be cut in order to get them to go round the curve of the cutting.  They are resealed with plaster to conceal the joins.





This one has cast plaster rock at the end intended to replcate real naturally eroded rock melding into blasted rock modelled using plasterboard.  I also use some cork bark for the bit above the tunnel mouth.  It is easier to fix in position than plaster and comes in handy in awkward positions like this.  More weathering is still to occur and will be going on for some time to come.  I also need morelichen as I have run out with all that I have used so far.  I have ordered a few Heki pine tree kits as I need a phenomenal amount of these to replicate the Alpine scenery. These will go on top of the slopes and up and down them.  Still have loads to do with the lower slopes. :wacko:



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Neil, now that is looking sharp! Very informative thank you. I will be referring back to this in about a year. :(  :(  :(

Wayne

My Layout "The South Shore Line":
http://yourmodelrailway.net/view_topic.php?id=509&forum_id=21
This video/animation was made in Adobe Flash Player, which is no longer supported or available for download.
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Some very good looking rock there, Neil, and much less messy than applying wet plaster. A good use of scrap material.

 Mike
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i like this idea and , i have a idea, which when i can i shall have a go and incorperte some of what you have told us on here and let you know  :D
Phill
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Excellent Neil - just what I wanted !!

In reading your opening remarks about rock strata, I wondered if plasterboard could be used for exactly that laid flat ?  You could maybe glue pieces of it one on top of the other "end on" if you get what I mean.  This might give you the often seen sloping stratas of exposed bedrock.

I've got some odd bits of board lying about and might give it a try for myself - it might appear on the much awaited "project" thread !!  :roll:  :roll:

Petermac

'Petermac
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Petermac said

Excellent Neil - just what I wanted !!

In reading your opening remarks about rock strata, I wondered if plasterboard could be used for exactly that laid flat ?  You could maybe glue pieces of it one on top of the other "end on" if you get what I mean.  This might give you the often seen sloping stratas of exposed bedrock.

I've got some odd bits of board lying about and might give it a try for myself - it might appear on the much awaited "project" thread !!  :roll:  :roll:

Petermac

Yes, that certainly is possible.  It would also be possible to do stone walls or bridge sides if you had the patience to inscribe the correct markings on to the side.  Brick would be more tricky as it has to be very even. As stone is more rough cut you have a decent margin for error.


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Hi Neil.  I am a bit late with this thread, and the photos have disappeared. But, it sounds like it would fit in with my â€œ Inglenook Junction “, which is/ was supposed to be portable, and it was originally lightweight. Obviously the more one adds the heavier it becomes. I am trying to add a rock face to my scenic break without adding too much weight.
My question is what can I do to keep that weight down?   Best wishes Kevin 

Staying on the thread Kevin.
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This is an old thread Kevin!
I’d highly recommend extruded polystyrene and some sculptamold. I got the extruded polystyrene free from a guy who had built an extension as its chargeable to take it to the recycle centre!

It’s very light and easy to cut and glue off cuts in place to shape it how ever needed!


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And then the sculptamold is a little like cottage cheese once you add some water  it gives you about 20 minutes to apply. I usually make it in small batches as it’s easy to join with the last bit
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Hi Chris. Thank you for your reply. I guessed that it was old by the fact that the photos had been deleted. I have been out shopping today, the first time since being discharged from hospital, a British Red Cross worker accompanied me otherwise I would not have been able. My legs were leaden? by the time I got home. As soon as I am able I will be on the lookout for likely materials. Best wishes Kevin 

Staying on the thread Kevin.
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Hi Chris. Thank you again. It looks like you are an experienced user. Best wishes Kevin 

Staying on the thread Kevin.
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Not experienced! Still using train and error. 
One good thing about the foam is you can completely mess it up and still stick it together and make it work! Haha
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