Accucraft's live steam K-27
A review

by Marc Horovitz
(2-19-03)

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Specifications
Builder Accucraft Trains (China)
Gauge 45mm (gauge 1)
Scale 1:20.3 (15mm = 1'-0")
Boiler Copper, silver soldered, twin flue, gas fired
Fittings Safety valve, filler plug, throttle, pressure gauge, water glass, blowdown valve
Fuel Butane
Blow-off pressure 70 psi
Cylinders Two fixed, double acting, D-valve
Reversing gear Walschaerts, controlled by lever in cab
Lubricator Displacement, with drain
Other features Fully sprung chassis; working drain cocks,
Dimensions 36" long (engine and tender); 5-3/4" wide; 7-7/8" tall
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1:20.3 scale, gauge 1, live-steam K-27
Accucraft Trains
31112 San Clement Street
Hayward CA 94544
Price: $3,999.99
Web site: www.accucraft.com

Pros: Highly detailed scale model; excellent fidelity to prototype; easy to operate; will run up to an hour unattended; can be radio controlled; will pull prototypical-length train; large boiler; large fuel tank; will self start, even when cold; correct scale-to-gauge ratio

Cons: Lubricator cap a little awkward; drawbar is too long for prototypical coupling; blowdown taken from top of water glass instead of bottom; access to valves (for setting or adjustment) difficult; toy-like safety valve; no pumps provided; front coupler a little high

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In 1902, the Denver & Rio Grande Western Railroad ordered fifteen K-27 locomotives, which were delivered in 1903. These were numbered 450 through 464. The “K” designation was the Rio Grande’s code for a Mikado, or 2-8-2. The “27” referred to the locomotive’s tractive effort, in this case 27,000 pounds. Two of these locomotives are still running today, one in Michigan on the Huckleberry Railroad, and one on the famous Cumbres & Toltec line in Northern New Mexico/Southern Colorado.

Our review sample is a model of Nº 461. As narrow-gauge locomotives go, the prototypes are exceedingly large engines. The model, consequently, is also quite large, so make sure you have enough clearance and large enough radii (8'-10' should do) on your railroad to handle them. Accucraft’s offering is well made entirely of metal. All side rods and valve-gear parts are nicely proportioned. The boiler is made of silver-soldered copper and operates at around 70 pounds per square inch pressure. The locomotive burns butane gas, which is housed in a tank in the tender under a dummy, lift-out coal load. There are two flues in the large boiler, each of which contains a standard “poker”-type burner. Twin, removable gas jets are attached to the end of a single, flexible line from the gas tank.

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Boiler fittings include a water glass, pressure gauge, and needle-valve-type throttle in the cab, and single safety valve housed in the steam dome. The safety valve, while functional, is of a type commonly used on toy engines. On a model of this caliber, I would expect to see a standard pop-type safety. There is a reversing lever on the right side of the cab and a displacement lubricator on the left.

Locomotive and tender are coupled via a drawbar. This has two holes in it for variable spacing of the engine and tender, depending on your minimum radius. However, even the closest spacing is too far apart and the apron between loco and tender cannot engage the tender deck, so just hangs behind the loco. I’d like to see a drawbar with more holes, including one that will allow prototypical coupling between loco and tender.

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An interesting feature rarely found on locomotives of this size is working drain cocks on the cylinders. In the “open” position, drain cocks allow condensate to escape the cylinders when they are cold and also assist in heating the cylinders. There is a small lever at the front end of each cylinder that is used to manually open and close the cocks.
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Operation of this locomotive is fairly straightforward. All moving parts must first be oiled with a lightweight machine oil. The boiler is filled with distilled water through a filler plug atop the boiler in the cab. It takes a large amount of water—around 600 ml—to bring the level up near the top of the glass. Water in the lubricator from the last run can be drained by removing the cap (which is a little difficult because of the lubricator’s proximity to the cab wall) and opening the drain valve beneath the cab on the left side. The drain is then closed, the lubricator tank filled with steam oil, and the cap replaced. The butane tank in the tender is then filled. It is also large and takes a lot of gas. You’ll probably need a special adapter for this, not supplied.

I did all of this prep work on the bench, then placed the engine on the rails. To light the fire, I opened the smokebox door (which just snaps shut), struck a match, and opened the gas valve in the tender a little. The fire lit right away in both flues, flashing back to burn above the pokers with a slight “pop”. I found, through experience, that it is possible for one burner to go out while the other stays lit. The one that goes out will not self light from the other one. There is no real way of knowing, except by the sound of the burner (which takes practice to detect), if one has gone out. However, this didn’t happen often, so should not be a major concern.

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Because of the size of the engine, it takes a while for pressure to come up—between 15 and 18 minutes during our tests in a variety of different weather. On colder days, efficiency drops because the storage pressure of butane gas declines as the ambient temperature falls. If the tank is near the boiler, this is generally not a problem. However, in this engine, it is isolated in the tender. The way around this problem is to fill the reservoir in which the gas tank resides with warm water.

Once pressure had come up to the blowoff point (around 70 psi), I removed the cab roof, put the engine in forward gear, and opened the drain cocks and the throttle. Steam hissed from the cylinder drains and condensate was expelled. The engine slowly moved forward as the cylinders warmed, then strongly took off. I found that the drain cocks would not completely close, so steam could be seen coming from the cylinders at all times during operation. This did not seem to affect the way the engine ran, though, and it looked great.

After the engine ran a couple laps around my track, I tied on a train of four, heavy Accucraft freight cars and a very heavy all-metal caboose. The engine walked away with these and would no doubt have handled several more. Top speed was a sedate (estimated) 25-30 scale mph. The throttle knob can be more-or-less conveniently reached with the cab roof on, but the reversing lever is more difficult. Our review sample ran slightly better in reverse than forward, probably a matter of the valve setting. The valves on this engine are more difficult to get at than on other locomotives. This is a model of a piston-valve locomotive, but it uses D-valves. These are concealed beneath the cylinder covers, which must be removed. The footplates above the cylinders must also be dismantled before you can get to the valves for adjustment. Full Walschaerts gear controls the valves.

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After steam was raised, our sample ran for a full 50 minutes. In better weather and with a top-up of the gas after steam is up, runs of an hour or more can be expected. The run was generally steady, with pressures hovering between 40 and 50 psi. By the end of the run, the water was well below the bottom of the glass, which really isn’t tall enough. Still, without the visual aid of water in the glass, you don’t know how much is left, so a close eye must be kept on the engine. The boiler is of a simple design and is not demanding, as far as attention required during the run.

At the end of the run I blew down the boiler, using the valve under the right side of the cab. The takeoff for the blowdown is at the top of the water glass, not the bottom, which is usual. Because of this, blowing the boiler down will relieve the steam pressure, but will not drain the boiler.

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As supplied, the engine has neither an axle pump nor a tender pump. So, at the end of each run the fire must be extinguished and the boiler blown down before the engine can be fueled and watered again. I would like to have seen, at the very least, a tender pump provided as standard, so that the water level could be kept up for the entire duration of the gas, and the gas tank quickly refilled to continue the run without first having to blow down and refill the boiler.

No provision is made for radio controlling the engine, but it shouldn't be too big a job. You'll need two servos—one for the throttle and one for the reversing lever. There is room in the cab for these. The rest of the gear could be mounted in the rear part of the tender.

If you are looking for a sophisticated steam locomotive that requires a lot of hands-on attention to achieve the best performance, perhaps this locomotive is not for you. However, if what you want is a good, solid, accurate, well-built model of an interesting prototype, one that can be fired up and more or less ignored for the next hour or so, this is definitely one to consider.

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Sidestreet Bannerworks, 2003