Thursday, September 24, 2020

How I constructed the Boneworks building

 After modifying the track layout at Bulkeley Station (see How I changed the track layout at Bulkeley), I now had a new siding at the back of the station which needed a lineside industrial building as a backdrop. I considered possible candidates such as a brickworks or builders' yard, but eventually opted for a boneworks. There used to be a boneworks near to where my hypothetical railway is located and I quite like the idea of having a slightly something out of the ordinary on my railway. The actual buildings of my local boneworks were not particularly inspiring, ......

 ..... and so searched for something which looked more interesting. Eventually, I discovered the Etruria Bone and Flint Mill building which was (and still is) located in Stoke on Trent.

This is a much more attractive building and so I measured the intended site and drew up sketch plans for my model version. I had to reduce the length slightly by removing one set of windows and reducing the gap between them, but I think I have retained the spirit of the original in my model.

 The dimensions for the real building were determined by counting bricks and making an assumption about the size of the bricks used (9" x 4.5" x 3" (inc. mortar)).

I then purchased three A2 pieces of of 5mm thick PVC foamboard (Foamex) from Simply Plastics. The walls were then marked out on the foamboard.

The brickwork was also marked out on the board. The style of brickwork is quite interesting - three courses of sideways facing bricks (stretchers) followed by a row of end-facing bricks (headers). I've since discovered that is called "garden wall bond".

To keep thinks simple, my bricks are 12mm x 6mm x 4mm which is near enough to a standard brick size in the UK. The horizontal mortar courses were scribed with the flat blade of a screwdriver and then....

..... the vertical courses were indented by placing the blade of 4mm wide screwdriver into the horizontal course at an angle ........

... and then bringing it round to the vertical position while applying pressure.

This process was repeated until the entire wall had been embossed.

I prefer to mark all the bricks in pencil before scribing and embossing as it is very easy to make a mistake. While marking out the bricks in pencil first helps to reduce the likelihood of a mistake, a lapse of concentration can result in a mortar course being embossed in the wrong place (usually diagonally across a row of bricks!). This can be remedied by filling with Squadron White Putty and, when dry, re-scribing.

 Once all the bricks were scribed, the walls and windows were cut out with a craft knife.

The fancy brickwork was then scribed, such as the arches over the window openings.

The front wall of the engine house was tackled next. The curved sections at the top of the wall were drawn by eye on a card template which was then drawn round and flipped over to ensure the two sides were identical.

The side walls were then measured, scribed and cut out. Their depth was determined by the size of the available site.

Talking of which, as a break from scribing, the site for the boneworks was prepared.

Firstly, the foliage was cleared .....

..... and a shallow trench dug approximately six inches deep.

A two inch layer of rubble was laid and tamped down.

Plywood shuttering was placed around the outside of the trench with a piece of 2"x1" timber screwed to the breeze blocks at the edge of the siding to provide a profile for the front edge.

 Mortar courses for stonework had been marked on this piece of timber and the courses then traced over with lines of glue from a hot glue gun.

A 3:1 mix of sand and cement (with a small amount of red and brown cement dye added) was then trowelled into the trench .........

...... and smoothed off with a piece of timber.

A spirit level was used to ensure the cement was level - though a slight rake was included from back to front to encourage drainage of rainwater.

The concrete as left for a day to set and then the shuttering was removed and the upper surface of the platform scribed to represent the platform edging blocks.

 The concrete slab was then left another couple of days to fully harden.

The walls were then glued together with thick superglue and test-fitted into the site.

Card templates were then made for the roof sections. The card allowed for some tweaking to ensure the roof sections were exactly right before cutting into more expensive materials.

The roof sections were then marked and cut out. I would have used 3mm foamboard, but did not have enough available and so used 5mm foamboard.

After gluing the roof sections in place, the building was once more test-fitted to see what it would look like when in situ.

Fortunately, it looked OK and so I progressed to the next stage - tiling the roofs.

20mm wide strips of 1mm thick plasticard were cut out and marked at 10mm intervals. A line, 8mm from one edge was drawn across the top of the strip.

Nicks were cut into the strips at 10mm intervals up to the 8mm line. I have found that scissors are the best way of making the nicks. I cut each division twice, with roughly a 1mm gap between the cuts. Although this exaggerates the gap between each slate, I have found that, although single cuts would be more representative of the slate roofers' skills, in model form, they become clogged with paint and hence the divisions between the slates disappear.

Horizontal lines at 12mm intervals were then drawn on the roofs. I have previously tried putting the strips on the roofs without these guide lines and discovered to my cost how quickly the rows of tiles became skewed.

Starting at the bottom edge, the first row of tiles was glued to the roof using thick superglue.

Subsequent rows were then glued on, overlapping the previous row. I found that two lines of thick superglue were needed to stick down subsequent rows.

The back of the strip was sprayed with superglue activator to help the strip stick quickly to the roof. The strips have a tendency to curve once they have been snipped with the scissors and so I have found it's useful to be able to straighten the strip as it is applied and have it grabbed almost instantly by the glue.

The process was repeated until the entire roof was tiled. From time to time, 'slipped' slates were cut from the strip and glued separately into the rows.

As the roofs of the boneworks are hipped, once one section of roof had be tiled and the glue had fully set, the excess pieces of tile strips were cut off using a razor saw.

The tile strips on the second section of each hipped roof were trimmed to size before they were glued.
Once the tiling was complete, four types of ridge tiles were drawn using TinkerCAD  

 ....... and then printed out on my 3D printer. I needed two different pitches of ridge tile and two different styles - one with a lip and one without.
I have made these ridge tiles available on Thingiverse if anyone else wants to use them -

The tiles were then glued to the ridges using thick superglue.

The sills for the windows were then cut from 1.5mm plasticard .......

..... and glued beneath each window opening.

8mm wide of  Plastruct I section ........

...... were then glued into place above the lower window openings as lintels.

The mortar courses were then filed into each window opening and around the corners of each all using a triangular needle file.

The whole structure was then given a couple of coats of Halfords grey primer which was left to harden off for a couple of days.

The walls were then dry-brushed with a blue-grey mix of acrylic paint, using a wide flat brush. The paint was applied very lightly in a diagonal direction to try and avoid depositing any in the mortar courses.

Inevitably, no matter how carefully the paint was applied, some ended up in the mortar courses.

This was remedied by waiting until the brick colour had dried, and then applying light grey in the polluted mortar courses ........

..... and immediately wiping off any excess with a dampened finger or thumb-tip.

The roofs were firstly given a wash of very dark grey acrylic ......

.... which was then wiped off immediately so the colour was deposited into the cracks and crevices.


Once this had dried, the slates were given a very light dry-brushed coat of pale blue-grey.

 Meanwhile, the window frames were drawn in TinkerCAD (see How I drew window frames for 3D printing using TinkerCAD)

...... and then printed out.

They were then painted with acrylics .....

...... and, once dry, flipped over and UHU clear glue applied with a cocktail stick.

A suitably sized piece of clear acrylic sheet ..........

...... was then carefully dropped on to the frame and pressed down to help the glue stick. I have tried various methods to glue glazing to window frames and, while not perfect, I find that UHU (or clear Bostik) does a pretty good job.

The frames were then glued into the window openings with more UHU glue.

Barge boards and soffits (from 8mm wide x 1.5mm thick plasticard) were then glued into the eaves.....

...... and a door cut out and scribed using 3mm thick foamboard.

The building was then ready for final detailing and finishing ..........

...... following yet another location photoshoot.

 The ridge tiles were 'cemented' on to the roofs with grey Milliput.


This was carefully trowelled into place with one of those tools used by dentists for applying fillings. I find that dipping it into water occasionally helps to give a smooth finish.

 I also tried sausages of white BluTak, rolled and squidged into place. I found the BlueTak was a lot easier to control, but I will evaluate it in a couple of years' time to see if it is as effective as Milliput.


Once it had dried, I tidied up around it by re-painting the ridge tiles or slates with the appropriate shades of grey acrylics.

Gutters and downspouts were drawn with TinkerCAD .....

...... printed out ......


..... smoothed down and given a coat of grey primer ......

... followed by a couple of coats of green acrylics to match the window frames and barge boards. The gutters were then glued into place on the barge boards .......

 ...... and the downspouts glued to the walls.

I am not entirely certain about the efficacy of 3D printed guttering. It is quite flimsy and so could be susceptible to damage when the building is being stored or deployed. Previously, I have used brass channel and copper tubing to represent gutters which are, of course, a lot more robust. The 3D printed parts need a fair amount of tidying before they can be painted which, to my mind, equates to the amount of time needed to construct the guttering from metal. I will be monitoring and evaluating the outcome and will let you know......


The beam engine (see How I constructed a beam engine from a kit of 3D printed parts) was then mounted on a false floor so that it would sit snugly inside the engine house.

 [Awaiting photo]

I haven't detailed the rest of the interior but felt the beam engine needed to be modelled as the window to the engine house is quite large. However, as you can see, it is not as visible as I had hoped and so my next plan is to add some LED lighting to the engine house. I am also considering adding sound effects to the building using a small MP3 player. However, I need to visit the bone mill in Stoke when the beam engine is fired (which I believe happens on the first weekend of every month) so that I can get some truly authentic sounds.