Once the frame is completed and you have made the necessary cuts on the layout support sheet, it is time to install the track. Although you may have pieced the track sections together earlier to determine locations of buildings, cuts, tunnels, and other structures, it is now time to make things permanent. Should you wish, cork roadbed can be installed first to support the track. IBL Products of West Bend, Wisconsin, makes such a roadbed with strips of cork and turnout pieces that can be used to support the track. I am not a particular advocate of roadbeds, but they do help suppress the noise and vibration of passing trains which can reverberate through the wood frame of the layout. Should you opt for roadbed, it will be necessary to mark the track locations on the layout so that the cork can be installed first.
I prefer to use Märklin spikes (8999) to mount the track, although Noch did make track screws at one time. You could glue the track down, but then removal for repair or modification would be quite difficult. Even though the track pieces lock together, spiking is necessary for long-term reliability.
Spiking Z Gauge track is not the same as spiking real track. A ten pound sledge hammer and vigorous pounding may work with real track, but Z scale track calls for a small hammer, tweezers, and a nail set. (A nail set is a cylindrical piece of steel which can function as an extension of the nail.)
Start off by assembling the track pieces in their appropriate order. When piecing the track together, make sure that both rails fit properly into the rail joiner of the other piece of track. Because of their small size, it is easy to join pieces of track together, yet end up with the rail of one piece resting atop, instead of in, the rail joiner. Run your finger over the tops of the rails to detect such a misplacement. As you go along, keep checking the alignment of the track pieces. This becomes even more important when you do the actual spiking.
As an aside, I have found that even the smallest oval of track will appear larger if it is slightly skewed in its relationship to the side of the layout surface. Since the train is not running parallel to the edge of the layout, the viewer's eye is not drawn to the layout edge. By avoiding this connection, the viewer looks at the train rather than the layout as a whole. It is surprising how effective this can be.
Once the pieces fit together, spiking can begin. Initially, drive the spikes in about halfway. (If you are using the catenary system you will need to install it as you spike your track.) Spiking halfway will allow you to make corrections without damaging the track. It is not unusual to find that by the time you have returned to the starting point, a serious misalignment has developed. If this is the case, you then can go backwards, removing the spikes and slowly averaging out the misalignment. This averaging out process also may involve gentle bending of the track. Although you can use a straightedge or ruler to make sure that straight segments are truly tangent, you will find that this process can be done equally well by eye. The straight and curved segments should flow together smoothly, without kinks.
When you are satisfied with the position of the track (and catenary), finish driving the spikes. Be careful not to drive the spikes down so hard that the track becomes distorted. Since the head of your small hammer is probably wider than the space between the rails, the nail set can now be used as an extension to drive the spikes home. If you are using plywood for the track support, you may find the spikes tend to bend as they are driven in. This happens because the inner layers of the plywood are sometimes much harder than the outer surface of the plywood. A light touch, along with patience, should get you through. If you are using a soft material such as Homasote® or foam core board for the track support, you may be able to use a pair of needle nose pliers to drive the spikes.
If the impossible happens and you discover a track problem after you have driven the spikes all the way home, do not give up hope. The spikes can be removed by gently working a straight-bladed screwdriver under the head of the spike. Using the rail as a fulcrum, lever the spike upward. Once enough of the spike has been exposed, you can grasp it with a pair of pliers and finish pulling it out.
After you have attached the track, drill holes through the support sheet and then thread the turnout control wires to the underside of the layout. Take care to keep the drill bit clear of the wires in order to avoid damaging them. At terminal sections, signals, and crossing gates, again drill holes to feed the wire through the layout surface.