Introduced: 2024
ScaleTrains.com's "Rivet Counter" SD40T-2 models are available either DCC-Ready or with a factory-installed ESU sound decoder. Each model has its own unique paint and detailing package (based on the prototype in question). These are amazing looking models with performance to match. In fact, these may well be STC's best running models to date.
Internally, these models are quite similar to STC's SD40-2 release (also 2024). The chassis consists of a metal base with a metal bracket screwed to the top (holding the motor and drivetrain in place). The motor is an open-sided 5-poler with skew-winding. Each motorshaft is equipped with a flywheel (although they are somewhat ineffective, as these locos start and stop on a dime without the aid of a decoder). Plastic driveshafts seat inside of the flywheels and connect to notched cups on the truck towers. Short metal shafts connect the cups to the brass worm gears mounted inside the truck towers.
The main PC board is screwed to the top bracket and receives current from the trucks by way of four wires. Separately wired boards fore and aft of the main PC board provide bright white LED lighting for the forward numberboards, headlight, rear numberboards, gyralight(s) and backup light. The headlight and backup light are directional whereas the numberboard lighting is constant (always on). Additional wires run from the main PC board to the motor and (for DCC-Sound models) to a speaker mounted inside the fuel tank. The decoder interface on the DCC-Ready main board is "E24".
All six axles are geared and all gearing (apart from the worms) is plastic. The wheels are blackened and low-profile (no problems on Atlas Code-55 track). There are no traction tires. STC's MTL-style automatic couplers are mounted to the chassis. The plastic fuel tank is screwed to the bottom of the chassis. Holes in the fuel tank are provided for the speaker. For the DCC Sound models, the speaker is seated inside of a pocket in the chassis.
All 12 wheels provide pickup by way of axle-end wipers (the axle ends seat inside of holes in said wipers). Wires soldered to the axle wipers transfer current to the main PC board. As pictured, the trucks are a rather complex assembly and removing them would likely be a rather daunting proposition. An extension on the top of the plastic truck tower assembly holds the trucks inside the chassis, so I guess you would basically have to completely disassemble the truck towers and disconnect the driveshafts in order to get the trucks off.
Shell detailing is beyond amazing, including see-through fans and side vents -
These are superb runners - smooth, whisper quiet, excellent slow-speed creep and a realistic top-end speed. Mine ran well right out of the box, so pre-emptive wheels cleaning doesn't appear to be required. Mine can creep through insulated frog turnouts at very slow speeds, so pickup is flawless. Pulling power is decent (if unspectacular), with mine able to handle about 35 assorted 40' freight cars through curves on level track (any more than that and the wheels are slipping). I didn't have any problems with the wheels derailing (even on 9.75" radius curves). The sound isn't bad, although perhaps just a bit thin and tinny sounding to my ear (which is pretty much my opinion of most N scale sound installations these days).
One minor annoyance I have with the ESU decoder is the whole protracted "start up" sequence the locomotive goes through when moving from a dead stop (basically the locomotive sits there making various noises for 4-5 seconds before it starts moving). All very prototypical I'm sure, but not something I really want to have to deal with (particularly when MU'ing an STC loco with some other brand of loco that just wants to go). Changing CV124 from 4 to 16 eliminates this behavior. Also, the default behavior is for sound to be off when you first put the locomotive on the rails (with F8 then turning it on). If you want the reverse of that (sound comes on when you put the loco on the rails and turns off with F8), set CV31=16, CV32=2, and CV419=32.
For the DCC-equipped models, some CV tweaking may be necessary in order to achieve optimum performance. Performing a CV54 "BEMF auto tune" (set CV54 to 0 and then hit F1) should smooth out most performance issues. Another option would be to lower the value of CV56 (default setting is 255) to reduce the amount of BEMF influence over the speed. Yet another option to adjust BEMF would be to increase the value of CV52 from its default setting of 15. Between those three CVs, it should be possible to address any BEMF-related glitches that might arise.
Prototype -
The unique EMD SD40T-2 "Tunnel Motor" was the backbone of the Southern Pacific and Rio Grande fleets during the 1970s and 1980s. They were distinguished by the see-through radiator grilles at the rear of the locomotive.
Features -
- All-new model
- Era: Mid/Late 1980s
- Fully-assembled
- Multiple road numbers
- Operating LED Pyle-National 20585 (Translite) "Gyralites"
- Body mounted knuckle couplers; Micro-Trains compatible
- Coupler box accepts Micro-Trains 1015/1016 couplers without modification
- Detailed cab interior with separate floor, rear wall, seats, and standard AAR control stand
- See-through standard 48” dynamic brake fan housings with fan blades visible inside
- See-through radiator intake compartment
- Etched-metal radiator exhaust grills with radiator shutters visible underneath
- Factory-applied wire grab irons, windshield wipers, trainline hoses with silver gladhands, and more
- Motor with 5-pole skew wound armature
- Dual flywheels
- All-wheel drive
- All-wheel electrical pick-up
- Directional LED headlights
- Printing and lettering legible even under magnification
- Operates on Code 55 and 80 rail
- Packaging safely stores model
- Minimum radius: 9 3/4"
- Recommended radius: 11"
- DCC ready with E24 connector
DCC Features -
- ESU LokSound 5 DCC & Sound decoder with "Full Throttle"
- Single cube-type speaker
- EMD 16 Cylinder 645E3 prime mover
- Operates on both DC and DCC layouts
Shell Removal -
To remove the shell, unscrew and remove the couplers. Once those are out of the way the shell will readily lift up and off.
Grade: A