Turnout 3A of Hartley Hill is progressing in that the diverging stock rail has been added - said like that the task seems so simple, not so as this post shall show. Just to make things a little more difficult, I have laid the diverging stock rail of turnout 3A and the through stock rail of turnout 4A as a continuous length of rail so as to maintain a smooth curve through the formations. For those who like such things, the track diagram can be found
here .
This photo show the single length of rail which is to represent, on the model, three separate lengths of prototype rail, to cover from the heel of turnout 4A through the toe of turnout 3A to the start of the corresponding check rail. This rail has been curved to shape. blackened, chaired and droppers attached (hence the rail is supported above the work surface to avoid damage to the droppers).
As the rail represents several "lengths" of prototype rail I have made cuts in the rail head to simulate the rail joints of the prototype. The presence of these "joints" has an impact on the chairing - see the keys of the chairs adjacent to the cut in the rail. This joint is near to the heel of the switch and therefore includes some bridge chairs, such chairs are used where the stock and switch / closure rails are so close that there is not enough space between the rails for two plain line chairs. On the right hand side of the photograph can be seen a dropper... added after the rail has been chaired and before blackening (getting things done in the correct order needs planning when laying more than one length of prototype rail using a single piece of 7mm rail).
I use Exactoscale ABS fishplates for joining rails... painted a greasy Chocolate colour whilst attached to the sprue. Each moulding is made of two fishplates, one with bolt heads and one with square nuts. Each pair of fishplates is joined by a bridge piece, that bridge piece has to be removed for use with the simulated rail joints - a split moulding is shown below the sprue.
Araldite secures the separate fishplates to the rail - for some of the pre-1900 track the nuts are on the running face of the rail as that is what can be seen in LNWR photos of the Victorian era, for the post-1900 track the nuts are on the outside of the rail (the non-running face). The rail joint is made using a jeweller's saw blade, something like a 4/0 which gives a gap of around ten thou (a scale 7/16").
Apologies for the scruffy appearance of the track bed, a consequence of the template / foam getting torn when the drill snags the copydex (used for sticking the underlay to the baseboard surface) and of the numerous alterations made to the timbering as the switch design evolved. In this photo the sprung track gauges from the S7 Group Stores are being used to secure the toe of the turnout as the first step in fixing the stock rail. The toe of the switch is one timber to the right of the RH gauge.
The first couple of chairs at the toe of turnout 4A need to be firm before proceeding along the stock rail - this is because trying to lay that rail with (a) a set at the switch toe and (b) gauge widening beyond the switch heel needs accurate positioning of the stock rail along the line of the turnout.. The gauges are left in position for about ten minutes after application of butanone, pressure is applied to the rail tops so as to enusre that the chairs are in contact with the timbers. Tins of baked beans are useful for holding chairs in place as the tin sits nicely on two gauges as shown (other beans are available...).
The next post is going to cover gauge widening through the closure plus the use of plain line chairs to hold the curve of the stock rail.
regards, Graham
One thing I did want to ask is about your gauges. I know the West Mersea chaps found that using gauges that gripped both sides of the rail head caused real problems later as it gripped the head square and then once the gauges were removed the chairs naturally spring the rail heads inwards, canting it slightly. And then only later when checked was the track found to be too narrow. Do the gauges you have stop this and have you come across this yourself ? 
On the DCC layouts the switch rail has been bonded to the stock rail on all turnouts using a nickel-silver plate under each rail at about the switch heel opening. For ultimate S7 godliness we should produce a range of appropriate SS, 2), 3P chairs to do all the work! 
