TRACK INSPECTION

 

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Inspect your T-Rail track before you use it to avoid installing pieces that will cause problems.

 

HARDWARE

 

Make sure the 771-9 rail plates are original or have the edges beveled to fit flat into the web of the rail. 

 

If the bolts are not original 771-10’s, check to see that the heads do not project beyond the rail head.  If original bolts do not seat into the rail web, it is because the bolt holes in the track are not centered.  See BOLT HOLES.  Projecting heads will be hit by tinplate flanges.

 

If the nuts are not original 771-11’s or similar barrel nuts, commercial nut drivers and the Lionel 771-4 wrench will not properly tighten them.  Grind the outside diameter of the nut driver to clear the bottom flange of the rail to allow standard nuts to be used.

 

The best option is to use original hardware.

 

TIES

 

A visual inspection of the cast “spikes” will confirm that none are broken.  Track with damaged or missing ties can be used where appearance is not important, but the remaining ties are possibly brittle and may break in use.

 

Measuring the overall width of the base of a tie will confirm if the tie casting is swelling and is therefore easily broken.  A wooden block with a 0.38 inch slot 0.25 inch deep will slip onto a good tie.  If any tie doesn’t fit the slot, that piece of track is not in excellent condition.

 

BOLT HOLES

 

The proper location of the bolt holes is 0.250 +0.000 -0.010 inches from the end of the rail and centered in the web of the rail.  An easily made gauge to check the location is to mount a pair of rail plates on a known good piece of track that has round holes.  Mate this test track to each end of a piece of track to be sure the bolts pass through the rail and rail plate.  If not, have the hole location corrected using a 0.062 end mill. 

 

In 1935 all track was made without bolt holes, using rail clips on all three rails.  Much of this track was improperly drilled because the taper of the track web caused the drill to wander (toward the end on the right rail: away from the end on the left rail).  t-railtrack.com will precision drill or correct the hole location on these pieces for $5 each.

 

LATE (POST 1937) 731 SWITCH BASES

 

The base of the 731 switch is subject to casting failure caused by contaminated metal.  This condition cannot be corrected.  If the length of the cast base is more than 11.690 inches, salvage the good parts and discard the cast base.  If not, proceed to inspect, test, and correct the base, rails, insulators, and wiring.

 

Remove the motor, common center rail assembly, swivel rail assembly, and neutral rail (Bakelite).

 

The motor mount should be flat within 0.06 inches.  Place a 0.5x0.5 spacer in the recess of one side of the motor mount.  Clamp the base on the spacer on a flat surface.  The opposite recess should be less than 0.56 inches from the flat surface.  If not, warm the base to 150°F to 200°F and slowly pull the far side of the motor mount until it is straight.  Repeat clamping the other side.

 

The base and rails should be level from end to end and side to side.  Support the point end of the base on 0.5 inch stock just outside the two edges of the motor mount.  Clamp the outside rails over the end support onto a flat surface.  The base should be 0.44 to 0.56 inches from the plate at all points.  If not, heat the base and selectively draw high areas down until the base is straight.  Additional spacers may be needed to support low areas.

 

Reinstall the neutral rail.  Verify the pivot point is flush with the cast base.  If not, the swivel rail assembly will not sit flat, causing the point rails to tip as a train passes over them.  This can cause derailments.  The condition is caused by a warped neutral rail.  Either straighten or replace the neutral rail.

 

Check that the point rails have not swollen and bowed outward or arched vertically.  Rest the point rail assembly on a flat surface and check that all four ends of the rails rest on the surface.  If not, the point rail assembly needs to be straightened or replaced. With the neutral rail properly installed, the points should not rock side to side when the curved rail is against the straight outer rail and is pushed downward or when the straight rail is similarly tested. With the common center rail installed, the points should swing into the outer rails without any gap at the tip of the points.

 

Inspect the paper insulators on each end of the short rails.  If any paper piece is broken or missing, it must be replaced to allow the non-derailing feature to work.  Check that the paper insulator between each short rail and the cast base has not been damaged.  Replace if necessary.  Spark test the short rails to an outside rail.  If the circuit is not open, correct the short.

 

Re-solder any loose wires.

 

Finally, assure that the wires to the short rails do not cross the center rail bus bar inside the insulating sleeves.  If the wires cross, the base will be too thick to sit flat on a rigid surface.

 

731 SWITCH MOTORS

 

Inspect the swivel rail pin.  It should have a rounded top and stand 0.25 inches above the moving contact assembly.  A longer, square top pin came from an 022 or 711 switch.  It can short passing under the common center rail.

 

Test the motor while mounted to the base to find if it will throw and lock with 12 volts to the center rail and ground to each of the short rails in turn.  If the motor operates from the controller terminals but not from the non-derailing rails, remove the motor and raise the spring contacts on the contact plate.

 

Repair or replace the motor if it fails either test.

 

© 2007 Donald K Hagar, all rights reserved.