Introduced: 2004 (revised in 2016 and 2018)
Atlas's Shay is quite an amazing locomotive. Not only do they look great, but they're actually superb runners as well. In fact, the only real problem with them is the fact that Atlas can't seem to make enough of them to meet the demand. Production runs over the years have been few and far between, and during the dry spells, prices have tended to go through the roof on these things.
As noted above, there have been three distinctly different versions of this model. And although the three versions share the same basic design, a lot of the individual parts appear to be completely different between the various versions.
The chassis and shell are all-metal, providing for decent heft. The motor is a closed-sided 5-pole Mashima with dual flywheels. A lengthy brass wormshaft is attached to each flywheel (with the worms then turning the main truck gears). Pickup is provided by wheelback wipers that contact all eight wheels. Tiny, sticky-uppy contacts on the trucks transfer current to small contacts on the bottom of the chassis. These, in turn, are connected to long, skinny contacts atop the chassis (said chassis contacts being separated from the actual metal chassis by small plastic insulator inserts). The top-side chassis contact strips, in turn, route current to the motor. So, no, not a split-frame design. But then again, no wires either. All four axles are geared. And apart from the brass worms, all gearing is plastic. Directional lighting is provided by LEDs wired up on either end of the chassis. The wiring for said LEDs is extremely flimsy and, as a consequence, I have yet to de-shellify one of these things without having one or more wires come unstuck on me (ugh). Couplers are chassis-mounted Micro-Trains. Wheels are blackened and low-profile (no problems on Code-55 rails). There are no traction tires.
All of the cool spinning / up-and-down "Shay Stuff" on the right side is completely separate from the motor and drivetrain. Rather, it's all turned by gears on the right-side wheels. And surprisingly, it's all fairly simple and easily disconnected/reassembled.
DCC-wise, it is important to note that Atlas has correctly designated these locomotives as being "DCC-Capable" (as opposed to "DCC-Ready"). This encyclopedia defines a "DCC-Ready" locomotive as being able to accept a simple drop-in decoder of some kind. "DCC-Capable" (or "DCC-Compatible", or "DCC-Friendly" or whatever else people are calling it) is a more nebulous designation, basically indicating that a locomotive's motor is electrically isolated from its frame and that there is room for a decoder someplace. But whatever the particulars, decoder installation in a "DCC-Capable" locomotive is going to require some sweat. Still, if you're game, it can be done.
Excluding all the "slightly different" parts (chassis, motor, etc), the most noteworthy difference with this version is that the old free-floating LEDs have been given the heave ho (replaced instead by tiny PC boards fitted with bright white LEDs). Also, the couplers were changed from MTL to Accumate. Performance is essentially the same as on the first version, although this newer version does appear to be a bit noisier than the original release (being somewhat "buzzy" sounding). Also, I found the wheel-blackening "stuff" to be a bit excessive on this new release (IE, performance is going to be a bit iffy until you wear the crud off the wheels).
The main difference with this most recent release is its motor. I guess Mashima went out of business, so they switched over to some sort of cheapie Motraxx job (which appears to be a 3-poler rather than a 5-poler). Additionally, the flywheels appear to have changed shape (presumably to accommodate the new motor).
Minor differences aside, all three versions are superb runners overall. Throttle response is smooth at all levels, the motion of all the various moving parts is flawless, pickup is great, and slow speed performance is impressive (although it is noticeably better on the earlier versions with the Mashima motors). Mine can easily handle pulling ten log cars around my layout (and probably a lot more - although, being a Shay, prototypically speaking it probably wouldn't be pulling huge long trains around). No problems derailing, and no problems on sharp (9.75"-radius) curves. And wow, that animated drive shaft with all of its up-and-down gizmoage is way beyond cool. Overall, I'd rate these models right up there with the all-time greats of N scale steam.
Prototype information -
Modeled after the Two-Truck Shay Locomotive that was built in the 1920s, this type of engine was used by many lumber, mining, quarry company railroads, other industrial railroads, a few common carrier short lines and major railroad systems for service in the logging and milling industries.
To remove the shell, unscrew the four tiny screws on the bottom of the chassis (two on either end). And since the shell won't lift over the couplers, you also need to remove one or both of them (said couplers tend to fall apart when free of the shell, so be careful). Oh yeah, and if you have the first version, be prepared to resolder the bulb wires (which are no doubt waiting to come unstuck on you).
Grade: A
Reviewed: 04/05 Model Railroader ("An N scale model of a two-truck Shay, highlighted by a remarkable representation of the Shay's sidemounted drive train that churns furiously as the locomotive moves down the track, has been released by Atlas. As with a real Shay, this model's drive train is an intricate assembly of rotating universal joints and shafts with sleeve couplings the slide in and out as the trucks swivel to follow track curves. An operating Shay mechanism in N scale is a remarkable sight, even if this one is just for show and not for go. (This model uses a conventional internal worm drive and truck-mounted gear towers for propulsion.) The external drive is fascinating, but its parts are extremely small and somewhat delicate... The model's dimensions closely match Shay prototype drawings. The die-cast metal body and chassis add needed heft to this stubby tank engine and have a pleasing level of cast-in detail. Separately applied details include a bell, hand grabs, and steam turbogenerator. Its pulling power is equivalent to 23 cars. At three volts our Shay delivers a silky 5.26 mph and creeps along at just 1.3 mph. However, we also found that the ultra-slow speeds make this tiny engine ever more sensitive to track conditions - the cleaner the better! All 8 RP-25 contour chemically blackened wheels pick up electricity. There's no provision for DCC and hardly any room to fit a decoder. With solid performance and intricate detail, this Atlas Shay is an interesting model of an exceptional steam engine. $199.95")