19. CORK AND CHEESE CLOTH

Much of the spline roadbed is now installed on the ATSGRR. After the spline is in place the next step is to sand the top smooth. No matter how careful the track crew tries to be there is always one or two strands of the spline that insists on being a bit higher than the rest. A belt sander does the trick to smooth the top as seen in the photograph to the right.

Once the top is relatively smooth the next step is to install cork for

the ballast and to provide a smooth service for the track. The cork is secured to the spline with white or carpenters glue and help in place while the glue drives by a few staples from a staple gun. Driving spikes into the spline is a bit difficult but with the cork in place this is an easy task. For turnouts it is more convenient and provides a smoother surface for the turnout to use sheet cork that matches the ballest cork in height to cut pieces that underlie the turnouts.

The scenery for the railroad will be constructed on a web of cardboard stringers covered with cheese cloth. A later post will detail this process as it proceeds. But for now rather than attach the cheese cloth to the roadbed after the fact it is easier to lay a piece of cheese cloth on top of the spline and then lay the cork ballast strip on top of the cheese cloth. This way when the cardboard stringers are in place to form the mountains and valleys this cheese cloth forms a very smooth transition from the roadbed the the scenery. This prevents separation of the scenery from the roadbed which has occured in the past.

Once the cork in in place the track can be spiked in place on the cork ballest.

18 STAGING TRACK

As soon as work resumed on the railroad the road gang went to work on laying track. As indicated in they previous diagrams the staging yard consists of a double ended yard with a ladder on either end. The longest track is more than 10 feet long, far longer than any train that will be able to make the 3% grade to climb the helix. The shortest track is about 3 feet long. The operation of the yard is to enter from the helix at the far end in the picture, proceed along the through track closest to the front of the yard (the left hand track in the picture) and then around the return loop at the end of the yard entering the ladder (shown in the picture) and being stored on one of the other six tracks in the yard ready for the next trip across the railroad. Since both ends of the railroad enter the helix this is true for both westbound and eastbound trains.

Details: If you have a causual interst in Model Railroads you may want to skip the following details which are primarily for those interested in construction techniques, materials used, etc.

Track: As indicated in an earlier post the track bed is homosote. The track is code 100 Atlas Flex track. This track is easy to use and is secured by means of a nail in about every 10th tie. The turnouts are a variety of brands rescued from the previous ATSG Railroad. They were salvaged when the railroad was disassembled. As a result the major construction task was to clean up the ends of the rails, repair sections which had come loose from their ties, and replace missing track. All the turnouts are #6 to facilitate the largest locomotive on the railroad (a Bachman Mountain 2-8-4).

An earlier railroad demonstrated the desirability of having a rerail section near the end of each yard track so that in the event of an accidental derailment cars are put back on the rail before leaving the yard end and entering the helix.

To ensure good electrical contact each of the joints between sections of rail are attached with a rail joiner and then soldered in place.

The control system on the railroad is Rail Lynx (more about this system in a later post). This is an infrared system similar to Command Control except that the control is a beam from the throttle transmitter rather than through the rails. The rails have a constant 12 volt current. This makes it necessary to gap the rails to prevent short circuits. These gaps occur just beyond the frog on each of the 13 turnouts in the yard. To make these gaps smooth the gap is filled with a small piece of styrene and then held in place with super glue. The filler is then filed to the shape of the rail. This prevents the rails from accidentally reestablishing contact if the rails expand (when the room gets too warm) or slip causing the gap to close.

The power is provided by a 15-20 amp regulated DC power supply (the brand of the power supply is Samlex but any regulated power supply works). This power supply has a 120 volt input and a 13.5 DC volt output.

The railroad is protected by circuit breakers which automatically disconnect when there is a short and reconnect as soon as the short is removed. The railroad has four separate circuits, each with their own circuit breaker, so that a short in one area does not cause the whole railroad to come to a standstill. The railroad has one circuit for staging including the helix, one circuit for the Ascape yard where short circuits are more likely to occur, one circuit for the main line, and a fourth circuit for all the industrial sidings where shorts are also more likely to occur especially during switching moves. The circuit breakers were purchased from Rail Lynx.

Wiring with this system is very simple. A pair of 14 gauge buss wires follow the track. 18 gauge leads are soldered to the track about every 3 to 5 feet and connected to the buss wires with tap connectors. Each turnout is also connected to the buss wire. Having wired an earlier railroad using block control I can assure you that this type of wiring is very simple in comparison. Obviously the track is always hot and the control comes from the receiver in each locomotive (more on Rail Lynx later). For those who are interested, the Rail Lynx control system was reviewed in the July 2009 issue of Model Railroader magazine.

The return loop at the end of the yard requires that the polarity of the track be reversed when a train is in the loop. Our plan is to control this reverse polarity automatically with a Circuitron Auto Polarity Reverser (AR-1CC). At this writing it has not yet arrived. A later post will report on its operation.

Turnouts in the staging yard are controlled by Tortoise switch machines. Many thanks to Doug Whetstone and Craig Harding for laying on their backs all afternoon installing these machines. A railroad of this size would not possible without the help of many hands. These machines are wired for route control, that is, setting a rotary switch to a track number lines up all the turnouts for this track. The system used was described in the May 2009 issue of Model Railroader magazine (talk about good timing for an article). The first set of turnouts have all been wired and they work as expected, each turnout slowly moving to the correct setting when the rotary switch is moved to the track number.

The control panel for staging is under construction and will consist of a rotary switch for the ladder at each end of the staging yard. It will also contain a closed circuit TV to show the far end of the yard to the operator to facilitate operation when the scenery is in place above the yard. It will also control a signal at either end of the railroad so that the staging operator can indicate to operators whether or not they are clear to enter the helix to enter staging. More about this control panel in a later post.

17 TIME OUT

Not much progress on the railroad during April and the first part of May. The president of the ATSG Railroad spend much of this time entertaining some cardiologists at Dixie Regional Medical Center. Unfortunately the procedures required some restrictions of activity and crawling around under a railroad was one of these restrictions. We are happy to report that the recovery is almost complete and the most recent visit to the physicians said no restrictions. However the chairman of the board still has a few restrictions being somewhat more conservative than the doctors.

So we are back and ready to move forward as seen in the next couple of posts.

16 STAGING

Before proceeding with the roadbed at Ascape, it was thought the better part of wisdom to complete the staging yard underneath. Once again previous experience and the many scars on top of my head from installing staging under a complete railroad suggested that it is easier to reach through the open benchwork than to reach into a 10 inch shelf to install roadbed and track. By the way my wife bought me a hard had for working under the railroad. When I remember to wear it I don't get so many scars form whacking my head.

Staging is an important concept in model railroading. The best thing to do is think of a Model Railroad as a stage where action takes place for the viewing public. On a stage there is a back stage area where actors prepare to enter the stage and perform their role. A model railroad is similar. There is a staging area where trains are prepared to enter the visible part of the railroad to perform their role, moving across the railroad while delivering rolling stock to various industries, picking up or delivering passengers, etc. For the AT&SG this staging area is under the town of Ascape on the left side of the railroad. The staging area is about 10 inches below the ruling grade of the railroad. Trains enter the railroad by entering a helix at the left side of the staging yard or the bottom of the diagram shown here. (See the post on the helix for more details).

On the ATSG Railroad the staging yard serves both ends of the railroad via the helix. The trains enter at one level of the helix, travel across the railroad and return at another level of the helix to return to the staging area.

The operation of staging is as follows: trains enter at the left (bottom of the diagram) and travel though the ladder track to the short track on the near side (right side of the diagram). They then proceed around the reverse loop and enter an assigned yard track via the ladder at the right side (top of the diagram) where they await their next assignment.

Staging also allows a staging operator to use the reverse loop as a yard lead to switch the staging yard to rearrange trains for their next assignment or trains can merely wait for their next turn configured as they were when they entered staging. Trains leaving the staging yard can travel either direction across the railroad depending at which level they leave the helix.

The staging yard is suspended from the benchwork above as shown in the photos. The base is 3/8 plywood covered with homasote as a base for the track. The homasote we used is in 3 inch strips so these strips are staggered to accommodate the ladder tracks rather than covering all of the staging area.

The reverse loop at the end of the yard is constructed via spline roadbed as previously described. The spline in this case is suspended by supports from the benchwork above. One could never construct a railroad of this size without the help of friends. Craig Harding and Doug Whetstone deserve an award for duty exceeding all expectations as they labored several hours before they successfully got the suspended spline roadbed installed under the benchwork.

The other engineering challenge was to match the height of the roadbed to the homasote. The homasote is 1/2 inch thick, the cork on top of the spline is 3/16 inch so the spline had to be adjusted to come just above the height of the plywood base of staging to match the homasote.

At this posting the staging area is complete, the homasote in place, the cork installed on the reverse loop and in most of the helix and we are ready to begin laying track.

15 SPLINE ROADBED

The Roadbed is the support under the track. The management chose to use spline for the roadbed for several reasons. First, it is much easier to bend the spine around curves than it is to cut plywood to the proper curvature. Second, spine tends to form a natural curve that provides natural transition curves.

A transition curve is one that gradually decreases the radius of the curve rather than a sudden change from straight to a curve of a given radius. This makes for much more pleasing curves that replicate curves on the prototype (real railroad) much more closely. However, the curves on a model railroad have a much smaller radius than the equivalent curve on the prototype because of the limited space.

So what is a spline? First we cut 1/4 inch Masonite into 1 inch strips. The first strip is placed on the joists or on risers to follow the plan for the track of the main line. This strip is held in place by screws placed temporarily on either side on each joist or riser.

After the first strip is in place the main line of the railroad is defined. The next step is to glue additional strips of Masonite to this guide strip. We mostly use hot glue to glue these splines together. The spline for this HO railroad required 8 splines to be glued together to form the roadbed that is 2 inches wide.

This process goes pretty fast but it does take a lot of strips and even more hot glue. If you have worked with hot glue you know that you have to work fast. We found that it is easier with a track crew (2 people), one to apply the glue and the other to immediately position and hold the spline in place. It is important to keep the top edges of the splines as level as possible during this gluing process.

The track crew found that when there is a turnout that the roadbed must accommodate this by allowing a spline to branch from the main spline. The crew found that gluing a small triangle to the first spline at the place of the turnout facilitated keeping the angle of the branching roadbed correct. The triangles were cut to accommodate the angle of the turnout. Most of the turnouts from the mainline on the Ascape Tennsion and Sulphur Gulch are #6 turnouts meaning that the branch line diverges 1 unit for every 6 unites of length. Again much more abrupt than the prototype but more practical for a model.

Where there are parallel tracks such as for a passing siding the crew found that it was more efficient to place a 1x2 between the splines as long as the parallel tracks were straight.

Once the splines have been glued it is critical that the top of the roadbed is level. We don't want the trains to lean from side to side as they proceed along the track. A very small difference in height on one side of the roadbed can made a noticeabledifference at the top of a railroad car as it moves over the track. It is inevitable that one or more splines slips up a fraction of an inch as it is glued in place. To level the roadbed the track crew found that a small belt sander was the tool of choice. The top of the roadbed is sanded until it is smooth and also to be sure that it is level.

With the spline roadbed in place it will be time to move to large flat areas where spline roadbed is not practical. This includes the staging area, the yard at Ascape, Park City, and Coalville. We are still working on the spline but come back soon for a description of the next phase.

14 THE TRESTLE AT SULPHUR GULCH

14 The Trestle at Sulphur Gulch

At last we get to see something that looks like a railroad rather than just lumber.

With the helix in place we needed to determine the location of the trestle at Sulphur Gulch. This trestle was constructed for the first version of the ATSG Railroad. It is based on a trestle that actually existed on the Southern Pacific Railroad many years ago. It is unique in that the trestle is on a grade (3%) and a curve. This was a challenge for the construction of the trestle. The trestle was constructed a number of years ago but perhaps a few details of its construction are of interest here.

The lumber was sawed from a single 1x4 piece of clear pine wood. Using a radial arm saw the 1x4 was first sliced into 1/4 inch strips. Using a miniture table saw these strips were then sawed into scale lumber of the various sizes needed for the trestle. Once the lumber was sawed the construction began.

The bents were constructed first by laying out the upright supports over the blueprint and held in place by double stick tape. The cross pieces were then glued in place for each bent. The glue was allowed to dry overnight and then the bent was turned over and the other side glued. This process was repeated for several weeks until all the bents had been constructed. A curve of plywood was then sawed to match the curve of the track where the trestle would be placed. This curve of plywood was then elevated to match the grade of the track. The track support on the top of the trestle were then placed on this curve under the location of the track and held in place with double stick tape. The bents were then glued to the track supports and held in a vertical position using a level. Then the cross pieces between the bents were glued in place. With the major construction completed the details were added such as ladders, a walkway, railings, etc.

This trestle has been stored for several years and has suffered some minor damage mostly to handrails and a few cross pieces but no structural damage.

Back to the present. It is necessary to have the trestle located before laying out the roadbed so that it is in the exact location necessary. The benchwork for the trestle is then build to accommodate its location. The operation has trains coming from staging into the helix and after a few turns exiting the helix onto the trestle. When the scenery is in place there will be a tunnel entrance just beyond the end of the trestle. The other end of the trestle leads to a track that has been blasted out of the side of a very steep cliff. This mountain and cliff will hide the helix when the scenery is in place.

So our challenge was to position the trestle to make sure it is lined up perfectly with the helix and then to build benchwork toaccommodate the roadbed leading to the other end of the trestle. Thisadditional benchwork was build around the benchwork that holds the helix as shown in the photos.

Once the benchwork was in place then the spline roadbed was lined up with the end of the trestle and supported on tall risers that will be hidden in the cliff that will go from above eye level (over 6 feet) to just above the floor. The track will then appear to have been blasted out of the cliff and then onto the trestle. You may not see this wonderful scenery in your mind's eye yet but check back in the near future and this scenery will appear.

If you have been following the progress on this reconstruction you may have noted that the location of Sulphur Gulch has moved from the peninsula in the middle of the room to in front of the helix. The chairperson of the board was very concerned that with narrow aisles for operators that a trestle on the back curve of the peninsula was sure to get damaged by giants in the land. Isn't it amazing that we can move a geological feature such as Sulphur Gulch to accommodate better viewing of this key feature of the AT&SG Railroad? Of course we will have to rewrite the history of the railroad to justify this move ... revisionsist history! The new location is much better, it provides a wonderful scene as visitors enter the railroad room and puts the key feature from which the railroad gets its name right up front. It is wise to listen to the chairperson of the board!

13 BENCHWORK

With the helix in place it was time to expand the benchwork. For those who may be new to model railroading the benchwork is the table that holds the model railroad. However in this case the management want flexibility for scenery. This means that we will use an open table consisting of support beams and open joists to which we will fasten the track and the scenery. With an open grid the scenery can extend below as well as above the top of the table. With a flat table top the scenery can only extend above the scenery.

The side of the benchwork against the wall is supported by TGI beams. These are beams that are usually used for floor joists. The advantage is that they are strong and can have a long span without supporting legs. We placed the TGI beams around the walls supported every 8 to 12 feet by a 2x4 leg that extends up past the TGI beam and thus supports the backdrop framework. (See post #7).

The front of our benchwork (table) is formed with an "L" beam. This is constructed of two 1x3s forming an L shape. The advantage is that the vertical board provides support and the horizontal board of the Lprovides a surface to which the joists can be screwed. The L beam is supported every 8 to 10 feet by a 2x2 leg. The L beam and legs were placed parallel to the TGI beams and vary in distance from the beams depending on the width of the railroad along the three walls.

Since the railroad room is a finished room with a hardwood floor which we covered with a non-glue vinyl floor covering (See post #4 ) it is very level, unlike some basement or garage floors. Therefore it was unnecessary to place levers on the bottom of the legs. To protect the floor there is a felt pad glued to the bottom of each leg.

The top of the benchwork consists of joists fastened to the TGI beam on one end and to the L beam. The joists overlap the L beam by several inches to enable the L beam and legs to be back from the edge of the layout. If the legs are at the edge of the layout there is a tendency to trip on the legs when running trains.

With the benchwork in place it is time to begin to lay the roadbed, the support for the railroad track.