Tuesday, 31 January 2012

The office block - part 1

In the far corner of the shop ground floor is the administration area. A very small space comprising office, with a large safe desk and wall shelves full of wonderful old leather-bound ledgers and suppliers' illustrated catalogues dating from the turn of the century.

In one corner of the office was the cashier's enclosed kiosk where the financial transaction was completed.

The entire structure was originally formed of many panes of glass held on position by very fine pine glazing-bars.

At some point (a few decades ago) the whole structure was re-organised to eliminate the cashier's kiosk, give direct access to the rear or the counter, and re-shape the perimeter form. It then became clad with pegboard to offer extra display surfaces.

In preparing for the making this particular component, I researched and experimented a fair bit on ways to represent the glass. I became clear?!? that any attempt at glazing on such a complicated model would become very demanding indeed.

One issue is that real regular glass is way too thick (I needed 0.3mm thick). Clear plastic sheet is available at that thickness, but is very difficult to keep in pristine condition with so many processes involved. It is also rather susceptible to "blooming" in the presence of Cyanoacrylate adhesive (my preferred approach for  joining very small components).

All this coupled with the fact that certain views through the model will mean peering through up to four layers of plastic (plus protective case), I decided to not represent glazing at all - other than the wooden frames and the complex glazing bars.

So, in starting the building process, I began with the lower panels of pine planking being represented with 0.8mm Birch ply. Very fine sections of Obeche is being employed in the fabrication of the framework and glazing bars.

Thursday, 26 January 2012

Flight of fancy

 Helena G Anderson, the project photographer and I spend a couple of days boxing up all the remaining retail stock, display fittings and then set about removing the pegboard panels. The result was a series of interior views of the shop that had not been seen for decades. It started to become clear just how open-plan the original shop must have been.

Helena take the opportunity of photographing newly-exposed views of the vast shelving structure. Note the lovely period lamp post across the road - still going strong.
At last, a single view that takes in the complete shelf/drawer storage installation

Another major feature of the shop is the original Victorian staircase. Until about a week ago, the staircase we almost completely clad in pegboard with products covering almost every part of the structure.

Modelling the staircase begins with with a solid block of lightweight foam. The profile layout is glued to the surface as a guide to cutting to shape.

Extended guidelines allow the bandsaw to be accurately set up for each cut.

0.8mm thick birch plywood in the form of tiny planks is used to clad the riser and the sides of the staircase, whilst the treads are fabricated in 1.5mm thick obeche. This allows a certain amount of sanding to emulate long-term wear and tear.

By staining and then sanding the leading edge of the treads, a real sense of wear can be achieved.

Now the basic carcase has taken shape, it is time to start putting the spindles and handrails together. Rather than re-invent the wheel - yet again, I am happy to employ some commercially available components in order to speed things up a bit. I was careful to design the model at 1:24 scale, or in doll house parlance - 1/2 scale. In this way, I will be able to employ some of the readily available tiny accessories that would be way too time-consuming to make from scratch.

Even though I bought the spindles and newel posts ready-made, a portion of them required extending in length, due to the design of this particular Victorian staircase, there are 2 spindles on each tread, so in each case, the rear one is longer than the front one.

The rather tall newel post on the half landing was easily extended with a nice piece of Lime wood and a couple of careful butt joints, but after failing to make an effective butt joint to extend the 2mm diameter spindles, I used very fine brass tubing to slip over the modified spindle end. Wood stain will obviously not work on brass, so I will resort to acrylic paint to colour these components.

Having solved the main issues on the first flight, the second flight came together surprisingly swiftly.

The handrails were fabricated from three fine strips of Lime wood, assembled to form a U-shaped groove. When turned upside down the groove provided a location channel to keep all the spindles in alignment. The top surface was then sanded to give a pleasing curved profile.

Staircase assembly completed, awaiting staining/painting. The temporary foam support will remain in place until the major assembly process begins.

Wednesday, 25 January 2012

The writing on the wall -part 1

Almost every square inch of the original shop interior is clad in stained and varnished pine, that's every wall and all ceiling areas.

Widespread use of interior timber cladding seen in the shop 1st floor sales area

It would be very straightforward to just mark out a bunch of parallel lines or grooves on sheets of wood, but this would visually fall rather short of a convincing, quality effect.

I have employed 0.8mm thick birch plywood as my stock material and cut it into 100's of "planks" 5mm wide. But first, I applied two tones of spirit-based wood stain (Antique pine & Yellow pine). I learned this the hard way. In my tests, I cut the wood into strips, and then stained them, and of course it was VERY time-consuming.

By cutting the material into individual planks, the various grain patterns and variations in the staining effects were broken up randomly - just like the real thing.

Even with wood as thin as this, the Proxxon was a bit slow and gave rise to slightly non-parallel planks. After much experimentation, I tried the big mother - my bandsaw.

By pinning 4 layers at a time onto 9mm plywood offcut material, the very course blade (4 tpi) gave a surprisingly clean finish. With the huge power of this machine, coupled with the wide blade, the planks were totally parallel when finished and required the minimum of bur removal afterwards.

All the solid brick walls on this model are 9mm thick and have been produced from a specialised foam that is new to me, Rohacell from Emkay Plastics Limited. It was selected after much deliberation because it take a nice impression when hand-embossing all the bricks on the exterior surfaces. More about that in a later blog.

Wall apertures such a windows and doors have been built up, rather than cut out from blank sheets material. This can be more accurate in terms of placement, and also ensures that the exposed edges can easily be made straight and square when that is a requirement. It is al too easy to allow a knife to wiggle off-square when attempting to hand-cut an aperture in sheet material.

The wood cladding for the interior is individually glued in position with cyanoacrylate adhesive, starting from a straight edge and butting each plank up close to the next. Care must be taken to avoid a gradual deviation from squareness. Repeated parallel guide lines are a good guide to keeping things square.

This is the rear wall of the shop, showing the ground floor and the first floor
walls having been clad all in one operation. Note the office window to the left 
of the picture. A few years ago this window was boarded up after a
break-in. This window was operational in 1920 - the date setting of this model.

Wednesday, 18 January 2012

Shelf life - part 2

Now the shelves start to be fixed in place. The spacing and squareness is determined by placing a series of temporary spacers cut from balsa wood. Care must be taken to avoid excess adhesive rendering the spacers permanently fixed. There is a noticeable variation in the shelf widths to be found on the original cabinet, with no more than two sets of each length - just to keep it lively.

Some basic wood stain colour has been applied to the raw material to simplify the later finishing process.

Then suddenly, a few hours later, the last shelf partition is being positioned.

Nearly 200 drawer compartments are represented by individual chips of 0.8mm thick beech plywood.
Prior to fixing in position with a tiny spot of cyanoacrylate adhesive, the drawer fronts were stained in two different shades of wood stain. This was to represent the two species of wood found on the original, re-located wall cabinets. It is thought that the entire stock of Adams shelves and cupboards originally came from a chemist shop in Ely.

The elaborate "egg & dart" moulding of the cornice is approximated
in this model by threading tiny glass beads onto a guitar string.
When threading was complete, and shaped to fit the cabinet, the assembly a glued into a mounting channel, then painted with Liquitex acrylic paints to match the "mahogany' stained pine of the cabinet.

To add a little life to the unit, I decided to fabricate couple of complete drawers and matching apertures. This will allow me to place perhaps on drawer partially open and the second could be placed on the counter for the purpose of weighing out the contents during a sale.

Thursday, 12 January 2012

Shelf life - part 1

One of the most complex elements in the whole model is the ground floor shelf & drawer unit which virtually fills the entire rear wall of the shop. This fine Victorian structure is thought to have originally come from a chemist shop in Ely.

The cabinet is an assembly of cabinets forming a composite unit of 188 drawers, 77 shelves and 39 lower compartments. From the appearance of different timber species, it is clear that various recycled items were brought together to result in the complete structure.

An overview of the shelf & drawer system. This view has not been seen
in decades. With the shop now ceased trading, we were in a position to
move all the pegboard product racks that were obscuring this original,
Victorian presentation.

View of the some of the drawers and lower compartments.

Intricate carved framing detail. The coving features a
variation of  the traditional "egg & dart" design.

The modelling of the shelf system begins with the lower framework and compartments being formed. I am using a combination of 1.5mm thick obeche sheet material for the main frames and rear wall planking, plus 0.8mm thick plywood for the thinner shelves and vertical dividers.

Cynaoacrylate (superglue) is used throughout to speed up the drying of hundreds of joint necessary to complete this task.

Construction of the cabinets begin, working on one of the scaled drawings
prepared during extensive surveys conducted in Autumn 2011

0.8mm thick birch plywood compartments glued in position.
The challenge here was to use the tiniest possible amount of  
cyanoacrylate adhesive to avoid gluing it to to the metal squaring block.
1.5mm thick Obeche cut into varying width planks which were butt
joined together to form the rear panel for the entire cabinet.
Rear panel planking in position and central drawer areas are blocked in
ready for the individual drawer fronts to be added

Saturday, 7 January 2012

The model begins

So Christmas is now just a memory, with the new years' day still to come, I can't stay away from the workshop.

In order to get a feel for how the interior of the shop will be exposed for viewing, I decided to take a chainsaw to the rough maquette. This led to a pretty rough-looking outcome, but it was pretty helpful in determining where the cutaways should be to render good views of the essential internal details.

Roughly cut apertures to help to get a feel for the cutaway interior views.

I am spoilt for choice as to where to start, but I have decided to go straight in and start on the shop portion of the model, from the ground up.

I put a lot of thought into what to use as my base material for the floor. The plinths (especially the large shop and forge component) are starting to get a little heavy - and that's before the rather large acrylic cover is accounted for. It was always going to be a two-person lift, but it's now going to be a two strong-person lift. With this in mind, I need the actual model components to be as light a possible, whilst remaining strong and stable. I ruled out card type options because of possible humidity/distortion effect, and after considering thin MDF, I settled on 6mm thick balsa sheets laminated to give the overall floor area I required. The balsa planks were laid out crossways to the direction of the floor board so as to even out any effects of distortion.

At this stage, as there are no walls to stiffen the panel up. I laid a reinforcing brace along the back wall, this will eventually be built upon to form the core of the rear wall cupboard and shelf complex.

The actual interior floor space of the shop is elevated above the exterior "porch-like area", which is in turn elevated above the pavement level. This was achieved by cutting away that area from the 6mm thick balsa and replacing it with some 3mm Foamex plastic. With careful cutting of the shapes, a simple butt-joint proved plenty strong enough without the need for any reinforcement requirements.

I chose 1.5mm thick obeche as the material for fabricating the floor boards. This material is one of the few things I have managed to slice up on the rather under-powered Proxxon mini circular saw. However, when the saw is not protesting with an ear-piercing screech, it does make a very smooth finish.

The position of all support beams were marked out on the substrate to ensure that every plank joint and fixing nail fell in the right place.

I had imagined that I would actually pierce the planks with fine wires to give the impression of nail, and experiments showed that short lengths of guitar string (a plain G) would give a very good result. I then realised that I need over 1800 nails - life just isn't long enough for that.  In the end, I decided to use the finest dressmaking needle I could find and fit it into a pin vice. This made a very handy tool with which to emboss holes to represent the sunken nail heads.

The underfloor heating grilles are indicated by insetting small tiles
of embossed aluminium, recycled from the cladding from an old
briefcase, left in the garden to rot for over 4 years.

Shop ground floor timbers nearing completion. This shot shows the two 
columns of underfloor heating grilles and the staining and antiqueing
colur sequence.