THE ALMOND BLOSSOM RAILWAY

Un Pequeño Ferrocarrile de Vía Estrecha - A Tiny Estate Railway Of A Very Narrow Gauge
TRACK CONSTRUCTION
 
 
I am using Cromar White 27mm high steel rail which has been galvanised. I ordered the rail in 2m lengths as I decided that 4m was too long for me to manage single handed. Also the extra joint gives ample expansion gaps bearing in mind the high temperatures that can be achieved during July & August. Thanks to the internet, I found a little firm in Farnborough that specialises the thermometers, of every kind. They have one that is magnetic and measures the surface temperature. As you can see the day I took this photo the rail temperature was 46degC. The highest I have recorded is 55decC.  
After much deliberation and costing exercises I decided to use the PNP plastic narrow gauge sleeper over a BPI recycled polythene one. Partly due to a 25% increase in the price of the latter, but also because the PNP ones are completely preformed, requiring no drilling or cutting. After several years in the sun I am happy that the sample supplied, although now lighter in colour, still retains its original strength. After hitting with a sledge hammer I found no damage!
A set of rollers and a ‘Jim Crow’ was custom made by Roger Greatrex and I am really pleased with these as they make track & turnout construction a joy. I find that steel rail as supplied is vary rarely entirely straight and the rolls are ideal for straightening as well as taking out any vertical bowing.
 
During the Summer of 2007, straight and curved templates were fabricated to facilite track assembly. The photo shows a curved template  being assembled. Thanks to Peter Ladbrooke from Cambridges MES for the mathematical calculations and assistance with  construction.
The cutting of curved rail is crucial if the fishplates are to remain opposite each other. Some people prefer staggered joints. I don't. We now have tables giving the shortening dimension required for the inner rail for 6 and 9 metre radius curves. These tables are only correct for Cromar White 27mm high steel rail at a gauge of 187.18mm. I am once again indepted to Peter Ladbrooke who provided me with the formula in order to calculate these tables. The tables also take into account the expansion & compression occuring to the outer and inner parts of the rail that occurs when rolling.
 
Off cuts of steel angle make excellent instruments for checking the gauge. I have three types the green ones are standard gauge at 184.5mm for straight, the red ones at 187.5mm for curves and the white ones at 186mm for transition from straight to curve sections of track.
 
A rail drilling jig is essential whether using alloy or steel rail. This one with hardened guide bushes was made for me by RE Atkins Engineering. The rail stop pin can be moved to allow drilling from the outside of either rail. 
Depending on the ambient temperature I normally leave a 1.5mm or 2mm expension gap. 
 

 POINT CONSTRUCTION

 
 
 
After constructing several 9m radius, track panels I built my first turnout. Cromar White supplied 4 sets of pre-fabricated steel templates for both the blade section and the crossing section complete with crossing. They also supplied the point blades and stock rails machined accordingly, so apart from minor fitment, rail curving and assembly, quite straightforward assembly really! I did not need to draw out a template on the bench as the Cromar White supplied base components were fabricated to my desired radius of 30ft. This made the positioning of rails easy
During May 2008 a second point was constructed. This one is a great improvement over my first one. I spent more time on the fit of the point blades and stock rail, taking off small amounts using a fine abrasive disc on the angle grinder.
As you can see, I am using BPI 50mm sq recycled polythene for the point construction as PNP do not supply anything suitable. The BPI section comes in nominal 3m lengths and is easy to cut with a hand wood saw.
With a bit of filing for fitment, the rails fit snugly into sockets on the crossing template.
If you are interested in track & point design construction, you must look out for a second hand copy of 'British Railway Track' published by The Permanent Way Institution. My copy is dated 1971 and was £3.50 when new!
I also located a supplier of square stainless steel washers when I was in the UK last year. These are preferable to using round washers.