Building a Curved Crossing on a Traction Layout
(A simple way that works)
by George Huckaby
April 15, 2004
The Southern California Traction Club started using their car storage and display modules in 2003 after thefts of brass equipment occurred at an east coast traction show. These display modules are located within the rectangular display so the public can see the cars but not have access to them. Upon using the display, it was found that the entry track to the yard worked very well and should be matched by a similar outbound track.
The original inbound track was created using an Atlas Code 83 #542 turnout mated to a section of #532 18" radius curved track. The crossing had been "grafted" into the section of curved track and was done while the module was under construction. This time the crossing would have to be fabricated off module and then "grafted" into existing trackage. Although this method would not probably be used by a Master Model Railroader, the use of curved and straight snap track with the rails already held firmly in the straight or curved position aids in keeping the correct track gauge, throughout this process.
Since this track will be used on a traction layout with operable overhead wire, insulating the two rails is not a factor, simplifying the entire construction and installation process.
This is not the only way to build a curved crossing, just a method that we have used twice, found that it works and yielded track that did not turn out to be derailment-prone in either case.
2. INITIAL PREPARATION STEPS
We will be using the same Clover House 266 printed circuit ties that we have used for the ORR Street Trackage in another lesson. These printed circuit ties are .056" in thickness while the Atlas plastic ties are .078". So a strip of Evergreen StripStyrene #8210 .022" X .112 will be affixed under each printed circuit tie. This crossing is to be fabricated "off-module" so a piece of plywood, on which to fabricate the crossing, was needed. A nearby construction project yielded a brand new section of 15" by 23" 1/2" plywood and the project was underway.
1. Since the module tracks are on two-inch centers, mark two parallel lines on the plywood, two inches apart and then draw an 18" radius curve tangent to the outer line.
2. Take the #542 turnout and attach the section of #532 curved track to the diverging route and lay out the track along the lines and using T-pins (called wing pins in some circles) fasten the track along the lines to ensure a correct fit.
3. While the track is in place, scribe a line along the edge of the ties to mark the tie edges on both the straight and curved tracks. These lines will be used to measure the correct length for ties under the crossing itself. This will also mask the difference between the plastic ties and the printed circuit ties.
4. Solder the rail joiners between the turnout and the piece of curved snap track while the two pieces of track are "pinned" in place.
5. Remove the pins and before moving the trackage, note how many ties need to be removed. Turn the track upside down and carefully remove the plastic ties along the curved track section where the crossing will intersect the curved track and then reattach to the plywood using the same pin points. Shown below is the project at this step.
3. INSTALLING THE CURVED PORTION OF THE CROSSING
a. Carefully begin to cut the printed circuit ties to fit between those tie lines that you scribed earlier. They will all be different sizes so each must be measured carefully. After the tie is and cut for the particular location in the crossing, use a sanding stick or sandpaper and rough the bottom side of the tie. Using ACC (We recommend the use of the CA4000 Light Cyanoacrylate Adhesive Delivery System. This ACC comes in a syringe type dispenser and we end up using the entire amount before discarding the tube. This systems is available from Dental Ventures of America, Corona, CA 800-228-6696), affix a piece of #126 StripStyrene to the bottom of the tie and using a small amount of rubber cement or Hob-E-Tac on the styrene, place the tie in place. Keep repeating this step until all ties are in place as shown in the next photo.
b. Once the ties are completed and are fixed in position, solder the inner rail to the ties from the outside only. We do not want solder on the inside of the rail as the guardrails will be placed there and we do no want these rails any higher than the running rails. This operation is being shown below.
c. Use a track gauge when soldering the outer rail, again from the outside only. There will be a flange guard rail adjacent to this rail also. Do not perform these soldering steps too quickly. Allow time for heat to dissipate between each tie soldering step or heat will expand the ties and when they subsequently cool, the track will be slightly narrow in gauge. Note the track gauge in the photo below.
d. The photo below shows a test car over the new trackage.
4. INSTALLING THE STRAIGHT PORTION OF THE CROSSING
The next steps involve installing the straight track portion of the crossing. This involves placing the track in the correct position to ensure a straight crossing in line with the rest of the straight track, installing the track to the curved track, installing the curved flange guardrails and fitting the remaining running rails and straight flange guard rails.
a. Position some straight sections along the scriber line from the ends of the printed circuit ties. Ensure that the tracks are along the same line and that when the rails are extended through the crossing the track will be perfectly straight. Measurement and eyes help here a lot. Carefully check the next two photographs:
b. This is the step where four lengths of rail are prepared to fit between the curved portion of the crossing and the straight tracks. Extreme amounts of filing will be required to get a good fit at the curved track. Take care and be patient. Start with a length of rail 1/4" longer than required. File, measure and check with the 'good old' eye test prior to installing. This is NOT the time to be in a hurry. Be patient and file and fit carefully. Install a rail joiner on the fixed straight track and when the final fit is made, the rail can be temporarily spiked to the plywood and when the position is correct, solder the rails to the ties from the outside. Two of the four rails to be fit have been installed in the next photo:
Do the same thing with the remaining two rails except add one important step. Use a track gauge as shown below to insure the correct track gauge with the already installed rail. This is important to avoid painful derailments later when the crossing is installed.
c. The next item will be to install the flange guard rails through the crossing. The general rule in fabricating crossed crossings in to complete the curved rails first and then fit the straight pieces in. Since these rails will be fit web-to-web to the running rails, this is the reasons why we recommended soldering the running rails from the outside. This will help ensure that these flange guard rails are not higher than the running rails. To give a natural look to this flange guard rail in a traction environment, the flange guard rail will extend all the way to the frog guard rails in the turnout. So prior to installing the flange guard rail, we clipped the flared portions from the plastic guard rails and will but our new flange guard rail up to it. The flange guard rail will extend from these plastic rails through the crossing to just past the end of the printed circuits ties.
1) Carefully trim the flared ends from the frog guard rails and carefully measure the length of rail needed.
2) Place the rail adjacent to the inner rail of the curve from the frog guard rail to the desired end. When the correct length is made, flare the end of the guard rail and install at first by temporarily spiking in place to the plywood base. Note both notes below and when the flange guard rail is determined to be the correct position, solder in place.
Note: If the rail joiner between the turnout and the curved snap track prevents the rail from being placed close to the running rail, use a Dremel tool and grind some of the web from the guard rail in the area of the rail joiner.
Note: Where the flange guard rail is over plastic ties, the molded spikes may also prevent the guard rail web from being close enough to the running rail. Use a soldering iron and heat the guard rail slightly and push the guard rail toward the running rail. Then using a 68 drill, drill holes in the ties for later spiking to the base after the turnout and crossing combination is installed in the final location.
Using the same methodology, installed the opposite running rail flange guard rail. The crossing now looks as shown below:
d. There are only four more pieces of rail to be installed to complete this crossing, two running rails and two flange guard rails for the straight track crossing. These cuts and files must be exact and fit snugly between the flange guard rails already Installed. Be very patient. Start with a longer piece of rail than necessary and file down to fit. The flange guard rails should be carefully soldered together at the joint and filed to make them prototypically correct.
e. Make one last check of all the soldered joints between the rails and the ties to ensure that all the joints are secure.
f. Check track gauge on both the straight and curved portions of the crossing and correct and discrepancies by heating joints and carefully moving the rails.
g. Prior to removing the crossing and turnout combination from the plywood is to paint the printed circuit ties using Floquil Rail Brown 110070 or Floquil Railroad Tie Brown 110014 and the results are shown below:
5. INSTALLATION ON THE MODULE
a. The combination crossing turnout combination is shown in the just after installation on SCTC module 969. More ties will be installed along with ballast and the installation will be complete.
6. FOR MORE INFORMATION
If you have any questions on this article, please do not hesitate to contact Trolleyville. If you desire to model street railways, review other lessons in the Trolleyville Schoolhouse and visit the EAST Penn Traction Club web site at www.eastpenn.org. You can email us at firstname.lastname@example.org with any questions. When asking questions about proposed track plans, please provide all data, especially a scale drawing of the proposed plan, so that we can answer your questions as accurately as possible.
Happy Trolley Modeling!