Wednesday, 4 September 2013

Track Laying

Curved Track
Curved rail is prepared in advance as per the straight rail except it is curved to radius to fit its location. Preparing curved track work is not very different than building straight track work and does not require any special skills. The real difference is that the rail's needs to be curved. To ensure that the rail is properly pre-bent into shape consider purchasing a Fast Tracks Rail Roller.

The Fast Track Rail Roller tool will not only make it easy to create smooth consistent curves, but will also ensure that the rail is properly pre-bent so that it will retain its shape over time. For curves use  track gauges to ensure smooth curved track work and is especially important at joints between individual sleeper bases.

Failure to properly pre-bend the rail for curved track work will result in failure over time! 

Track Laying General.
After preparing the road base and ensuring it is 100% flat the time has come to install the track work. What will be outlined here is the basic technique applied to that task. 

The golden rule is bad track work CANNOT be fixed...!

Curved Rail ready for Installation
The base as shown was fixed using acrylic sealant to the layout road base following the drawn center line and once the primer is dried the rail is inserted onto the tie plates in 840 mm length [ 40 feet x 3]. Each piece of rail is prepared for metal rail joiners at both ends and the plastic 6 bolt rail joiners are applied at  40 scale feet as described in the  the Turnout article.

Drilling Tie Plates for Spikes
The choice of the Peco Track Pins is described in the article on Turnouts which worked with no real issues so when problems occurred when spiking the rail it was a shock and required a rethink. The problem lied with the laser cut ply bases that the sleepers are attached to combined with the weakness of the pins. The pins fold up trying to be pushed through the ply base. 

Initially 0.020' [0.5 mm] drill was used but the pins just slipped into holes with little apparent holding power. The real issue was the short life and cost so another way had to be found. The answer was found in spring wire 0.020'' [0.5 mm] which was filed into a simple D bit by grinding 5 degree taper then form a point at the end. Using a small battery drill and chuck the wire drill cleanly through the sugar pine sleeper and ply base. In most cases the pins press in with a slight pressure were the pins fold up re-drill till success is achieved. These drills will bend to unbelievable angles without breaking and a length of piano wire will supply as many as any project would need. Another advantage is that the hole created appears to close up after the pin is inserted and develops excellent holding power.


Another problem was found with the foam base - it dose not resist pressure well but it was found that a scale ruler spreads the load enough to overcome this problem. To make this task easier adhesive was not applied at at the edges of the sleeper base.

Electrical Connection

Each rail is connected to the bus with 0.5 mm multi-core wire soldered to a brass tabs which in turn is soldered to the base of the rail . Even though the rail joiners are brass castings you do not depend on them to transmit DCC signal that the job of the wire.

Spiking Rail

When spiking it is critical that when the spike is inserted that it follow the path of the drilled hole. The shape point is necessary to successfully insert the pin but it will generate its own path and will fold the pin. 

In practice it has been found that the head of the pin should be bent from the normal axis to obtain a tighter fit. This is best done by drilling the hole at 5 degrees to the vertical. The pin is inserted until the spike pliers strikes the rail flange - using the pliers bend the head into the vertical and complete the insertion of the spike to the flange base

The Final Result

At this point the track is ready for weathering and ballasting which will be covered in separate articles.

Is there a downside its the speed but a looking at the finished product you are reminded it is all worth while - I think...!

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