Tag Archives: granite

The Bridge – the next chapter

Other than setting the bridge into the landscape and adding a bit of weedy flora, the road bridge is more or less done.

A Southern Region horsebox and 12T MOGO disappear under the bridge heading towards the MOD sidings...
A Southern Region horsebox and 12T MOGO disappear under the bridge heading towards the MOD sidings…

Here are the things I’ve learned:

  • Rendering stonework is not the hard part
  • Roads and lanes are very difficult. To start with, they’re not even black…
  • Pigment powder is very, very dense, no matter how little you think you’re using…
I'm going to have to think about that road surface...
I’m going to have to think about that road surface… Yes, the inside wall is whitewashed and there’s a wooden rubbing strip

So, I think it’s time to look at track… Let’s get something running!

Building Bridges

Where was I? Oh yes. I spent days, yes, days, applying stonework to my MDF bridge armature using my DAS clay technique.

In the end it looks great. A bit of a caricature of vernacular stonework if I’m honest, but as the scale gets smaller a bit of emphasis helps.

Okay. I know the arch is asymmetrical. But there’s a story behind it. At least, there will be…

A few weeks ago I was in Home Depot and I noticed in the shaky can section they had a textured “granite” spray, so this was a chance to try it out. After masking out the roadway and whitewashed walls and wooden rubbing strip I spent a happy moment in the garage carefully priming the structure. This paint goes on really thick, so take your time with several thin coats letting it dry in between

In the event it was pretty cold there, so the paint had a problem “drying” in the garage, so in the end I brought it indoors, where Mrs Hill and I spent a heady night with the bridge perched above a heating vent.

Once again, the texture was possibly a bit much, but as I started to render the surface back it started to look pretty good. I also started to pick out individual blocks in various shades of grey. Just a fine brush and a palette of black and warm white with the occasional bit of pink. Yes. Granite has pink in it. I also treated a couple of areas with a mossy green colour under ledges and in corners although these aren’t evident in the images, but will pull out when I apply the final matt varnish coat… I hope.

Initially I used dropper bottles to drip various mixtures of grey/cream to represent mortar between the stones. Moisten with “wet-water” first. If you dilute your mixtures correctly, at first the courses look pretty garish, but as the paint dries it cuts back. If I found any particular spot was looking a bit too much I used a torn edge of paper towel to soak up the excess. Once dry use a stiff dry-brush to cut it back further if required

You’ll notice that above the tracks I’ve tried to imply soot and grime from the steam and exhaust of the engines. Also, on the right I’ve started to suggest the cornerstones have been painted white for safety reasons. There will be a platform continuing under the bridge. I’m also going to place a light in there for effect – and the convenience of people waiting for a train.

Tailgating? What’s that?

And this is where I’m at. A bit of a local traffic jam on the bridge where the new NHS midwife is on her way to a prenatal home visit. Obviously, she’s new to Dartmoor from the Big City or she wouldn’t have a Morris Minor convertible. Just wait for the first real downpour or blizzard… Meanwhile the RAC guy is on the rounds, fixing the “Do Not Feed The Ponies” signs and rescuing damsels in distress.

So now the bridge awaits the application of  weathering powders and a bit of plant life sprouting from appropriate places before blending into the landscape.

The road surface – actually one of the most difficult modelling challenges – is also awaiting treatment a la Kathy Millatt, while the wooden rubbing strip is going to be aged using another fine product, MicroMark Age-It-Easy.

Moorscaping…

Prospect along the tracks from Boltorr Road platform
Prospect along the tracks from Boltorr Road platform
Just a progress report. Building your own world, even a tiny corner of it, is hard work!

It has always been a part of my brief to get as much elevation as I reasonably could and I have to say it’s working out.

Actually rather too well in that the Boltor Brook seems to have carved itself a fairly impressive gorge through the millennia so I’m having to rewrite the narrative a little. But there are gorges elsewhere on Dartmoor, so it’s not improbable. Besides it’s my universe, so…

The Boltor Brook has become a mighty gorge
The Boltor Brook has become a mighty gorge

Structural work on the dam’s basin is done and sealed for landscaping and water effects.

The iron rail bridge has been set in ready for track laying with a little final adjustment to the abutments to fix a couple of issues. It’s safely stored away while landscape effects go in.

Some plaster slip has escaped onto the masonry but this is easily brushed off for the most part and will be weathered, vegetised, etc when it all comes together, at some vague point in the future, or maybe in the past. You know what private universes are like.

From the dam overlook to Wynderidg trig point
From the dam overlook to Wynderidg trig point

Now the bulk of the terrain from the basin to the Boltorr road overbridge has to be set in.
Butelph's Cross (11C) and Wynderidg trig point loom above the tunnel
Butelph’s Cross (11C) and Wynderidg trig point loom above the tunnel

I’ve plotted the track of the access road to the dam with a turning point and overlook for intrepid walkers. The path progresses northish towards the road with a shortcut for sightseers from the platform.

I really have to start detailed thinking about the road overbridge and construction. This element acts as a scenic break too and has to incorporate a bus stop and normal access to the platform. This was built way before any modern disabilities’ acts, so it’s likely to be just steps down.

The permanent way and the dam access track head northish toward the Boltor road
The permanent way and the dam access track head northish toward the Boltorr road

Life is great when I rule the world. First day of spring, soon.

Boltorr Road Halt - original track plan - evolution applies
Boltorr Road Halt – original track plan. Workin’ towards – evolution applies

Time to get the mortar in – last mention, honest…

Spent a couple of days rendering the main part of the dam.

It’s actually ended up looking a shade or two paler than the bridge abutments which I was on the point of remedying until I did comparison between the two structures.

I used a different method of producing the granite blocks on the dam, inscribing the joints and blocks. This produced a surface which has slightly smaller blocks and less relief.

Now placing the two elements in position, the dam seems to be further away. The treatment has induced some false, but effective perception of depth which I am very pleased with.

Further weathering will take place when the model is in situ
Further weathering will take place when the model is in situ

I’ve also brushed a suggestion of moss and algae onto the appropriate sections of the wall. It’s subtle and effective, although not evident in the image.

I have also learned that it’s hard to mess up rendering and weathering structures. It’s almost impossible to overdo it. Stuff that looks a bit much in wet paint usually tones back as it dries, and besides, if you think it really is a bit much it’s easy to cut it back with a couple of dry brushes.

There are now a couple of iron fittings and a grating which remain to be rustified. I might also fit a couple of retaining ties on the slightly dodgier bits of the wall.

So I’m now able to set the structure into the landscape and concentrate on laying track across the bridge.

Roll on…

Time to get the mortar in

Having got so far, either by applying or engraving a million granite blocks to the the dam and rail bridge abutments, I’m now attempting to get a suggestion of the mortar in between the blocks to increase the perception and depth of a huge granite wall.

Well, I spent a bit of time on this today, but to no avail, except the surface has dulled down nicely. By far the best relief has been effected by stippling quite a dark grey over the block, letting it dry a bit then dabbing a mix of paler grey and white over, letting that almost dry, then stippling again to blend the shades.

None of that helped render the mortar boundaries. So I’m going to have to think about that again. I did try shaving some black and white pastels onto the surface, then dry brushing the particles in. This has been more effective in the image than in reality. You can see some of the white pastel particles on one side of the wall before they were brushed in.

Further treatment of the wall has taken off the sheen
Further treatment of the wall has taken off the sheen

I’m thinking that the only way will be, setting one surface plane at a time perfectly horizontal and applying a mortar coloured wash and letting it dry before moving onto the next wall surface.

We’ll see…

The Mason’s Arms

Since Dartmoor is largely made of granite it largely follows that most structures on the moors utilise this hard and heavy stone.

Curiously, a by product of the aging of granite is china clay. At school we referred to it as rotten granite. The southwest remains one of the most important producers of china clay in the world and its transport to more industrial areas is still largely done by rail.

Rolling the clay to about 1mm thick
Rolling the clay to about 1mm thick

Anyway, significant permanent structures on the Boltorr branch will be built of granite, or at least, I hope they’ll look like they are.

I’ve tried a couple of techniques. I rejected using embossed plastic card because it looks rather too sterile and certainly too flat. But, so far I think I’ve achieved the best results with air curing clay over foam board.

Broken chips and "biscuits".. Fingers do an excellent job of breaking up into scale size blocks
Broken chips and “biscuits”. Fingers do an excellent job of breaking up into scale size blocks

The dam was made by gluing a thin veneer of DAS clay over the board structure, then embossing stones onto the surface. This worked fairly well, but the results do not match the technique I have settled on. That is to make dressed stone looking chips of clay and sticking them on individually.

This sounds tedious, and to a degree it is a bit more labour intensive than just embossing the stones, but it’s far more satisfying and gives a more realistic 3D surface texture. It also make it easier to place reasonable looking corner blocks, cornices and other embellishments.

The building blocks are made by rolling DAS clay to a thickness of about 1mm. I do this by using a crumpled sheet of non-stick aluminium sheet – as used in cooking – a couple of coffee stirrers or similar and a clay roller.

DAS clay, cured biscuits and rough blocks, corner blocks ready for use
DAS clay, cured biscuits and rough blocks, corner blocks ready for use

Looking upstream with the new, more adequate retaining walls. Partially treated, but I'll wait until the whole structure is in place before final rendering and weathering
Looking upstream with the new, more adequate retaining walls. Partially treated, but I’ll wait until the whole structure is in place before final rendering and weathering

The clay “biscuits” take up to 48 hours to completely cure and dry. Then I just break them up as randomly as I can aiming for blocks with sides around 4mm to 6mm long. This represents 12-18 inches to scale. Some end up a little larger, some smaller. It doesn’t matter. Any that seem too big I just break in half.

Corner blocks are made by cutting strips from the biscuit and snipping off appropriate blocks squarely with a pair of side snips.

Since these structures are purely functional a bit of variation adds to the charm, so I measure very little. It just has to look right.

Next: How to build a granite dam…