BUILDING A GARDEN RAILWAY - PART 8

Laying the Track

Now that you have finalised the overall layout design and constructed the roadbed for your railway it's time to actually lay some track. After all the hard preparatory work some might say that the fun really begins.

Assuming that all the steps to this point have been methodically carried out to a satisfactory standard the process should not prove unduly challenging.

Whilst the procedures for laying track are more or less the same whether you elect to use sectional track or build your own you will still find wide variations in the methods used with each solution having its strong advocates.

One of the most contentious issues (amongst many) is the question of how to minimise voltage drop the further you go from the electrical feeds to your layout. Some will recommend that you have several electrical wire feeds to different parts of the layout. I am certainly no electrical expert but if you think about it the voltage drop on a long length of thin wire must surely be greater than on a thick brass rail section even allowing for the conductivity of copper. I remain unconvinced but you can try this if you like.

The greatest potential 'loss' of power is at the end of each rail section where it is joined with an adjacent rail. Loose joiners can often be a cause of voltage drop and should be as tight as possible and packed with a conductive grease to give good conductivity.

As previously mentioned some proprietary track (notably that supplied by Aristo-craft and USA Trains) rely on a 'belt and braces' solution of using special joiners incorporating tiny hexagonal screws to tighten things up. This can prove quite effective and far less unsightly than large terminal clamps (more later).

There is an equally strong faction who favour eliminating the joiner altogether and soldering every joint in order to create a strong mechanical joint and thereby eliminate electrical problems. Those who argue against this approach claim that this leaves no room for expansion of the rail in hot weather and will cause the track to buckle even where it is not permanently anchored in position and allowed to float in the ballast. You will need to read up on the pros and cons involved and decide for yourself.  

A simpler way to achieve much the same result is to solder a short piece of wire across each rail joint to 'bond' them together. These can always be removed at a later date if necessary.

There are almost certainly other solutions to the controversy but to avoid boring you on the subject I urge you to consult the wealth of published material on the issue.

You can fix the track in position by pinning to wooden cross-bearers laid in the roadbed but brass track is heavy enough to be allowed to 'float' in the ballast just like the real thing. If you are using a wood track bed it is customary to cover the top in mineralised roofing felt both to protect the timber and represent ballast. This can be quite effective and is relatively cheap.

The appearance of most track can look better and last longer if it is ballasted. Ballast is useful in providing adequate drainage and help to ensure that the surrounding soil does not encroach on the line itself (although in practice you will need to get used to constant maintenance in this respect if you wish to keep the soil and garden wilderness at bay). It is also sufficiently flexible to allow track to expand in hot weather and contract in cold temperatures.

Warning:  Ballast that becomes contaminated by soil is the perfect eco-system for weeds so regular maintenance is a must.

Code 332 brass track has sufficient mass to behave just like the real thing and will "float" naturally in well laid ballast particles.

The ballast itself can come in many different forms and there are local variations and types depending on where you happen to live.

The general rule I found is:

·           Size: 0.25" ( 6.35 mm) or less

·           Appearance: a mixture of crushed rock or shingle and dust   with sharp rough edges that will knit or lock together. Rounded rock particles will have excessive movement and are unlikely to bind together.

Crushed rock, granite chips or small shingle are good but pea gravel or chicken grit are probably best avoided.

Two methods of laying ballast appear to be preferred:

METHOD 1 : After having lined you trench fill with a layer of fairly course ballast (a depth of one inch or two should be sufficient).Then lay the track in position and gently "wriggle" or agitate the track section (not too violently) into place so that it is held reasonably firm by the ballast. Then apply a final layer of scale ballast between the sleepers and sides forming rounded edges. Tamper down with the square end of a small block of wood ensuring that the ballast is fairly level with the top face of the sleepers (which should be immersed in the ballast but not covered) and not obstructing the rail.

METHOD 2 : Lay the track directly on a shallow layer of ballast. Then gently brush additional ballast between the sleepers (ties) and each side of the sleeper - a chunky paint-brush is ideal for the purpose - again making sure that the top surface of each sleeper is left uncovered. You may need to tamper down the final lay of ballast between the sleepers with a suitably sized wooden block.

Special care needs to be taken at points to make sure that trains will have smooth passage. It is essential to ensure that no ballast is allowed to obstruct the running rails or the movement of point blades which must be free to move.

In both methods you may need to even out the under laying ballast level and remove some where there is excess to fill shallow depressions where there is insufficient coverage.

Check the track both width-ways and longitudinally with a spirit level to ensure it is to the required grade.

When is all finally tampered down and checked for stability some enthusiasts opt to 'wet down' the ballast with either water or a spray containing diluted water-proof PVA adhesive (that dries clear) with a drop of washing-up liquid to aid absorption. Certainly in dry weather this dampening of the track can help the dust in the ballast to solidify and strengthen the bond between top ballast and roadbed foundations.

Just as there are many ways of constructing the track foundations there are various methods of laying the track itself and every variation has it's advocates. There is no right or wrong way.

Self-Build Track is quite a different kettle of fish and you would be advised to read up how to go about it from the experts. Suffice it to say that this approach can be very satisfying and give excellent results but be prepared to devote many man-hours (or 'person-hours' in the politically correct days) to the pursuit of excellence.

When constructing your own flexible track from components always use a proper adjustable rail-bender for good results. The best machines for this  task (particularly the Swiss precision type) can be quite expensive but is you rely on other hand-bending techniques the resultant 'kinks' and wasted rail can prove just as costly.

One tip I've read about is to wrap a rubber band around the rail ends when 'feeding' rail through the ties to keep the latter from slipping off while you handle the track. It will also be easier to slide in the rail if you spray the plastic web chairs with WD40 or similar graphite based lubrication beforehand.