This review is on AHM's Center Cab Switcher diesel, made by Mehanotehnika (now just Mehano) in the 1970s.
Like most other Mehano produced diesels, the detail on this engine is pretty plain, with only the main details molded on (doors, vents, a couple grab irons, windows...). Some of the details are a little thick, like the hood doors and grab irons, while some others are so fine you hardly notice them, like the coupler lift bars, which they left the middle section off of. The vents on the ends of the hoods are see-through, which is a nice feature, but they're also a little thick. The handrails are molded onto the plastic frame, and are very thick and brittle. The walkways have safety tread molded on, which is something you won't find on most engines of this one's age. The paint is fairly smooth, but the color separation gets pretty fuzzy in some places, especially around the cab, where the colors leaked into eachother a little. The sideframe detail is good enough to look decent, but there are a lot of seems around it. The couplers are pretty high on their bars because of the low coupler boxes, so if you want knuckle couplers, you'll have to find some with a special height. There is one advantage to having minimal molded on detail, and that's that it makes it easy to add your own super details to improve its look.
The switcher ran quietly and pretty smoothly at all speeds, with only a little wobbling. At 12 volts, it reached a maximum speed of around 140 scale MPH, which is a little quick for a small switcher like this one. The slowest I could keep it running at was about 10 scale MPH, which is caused by the high speed gearing and severe motor cogging. The current draw running free at 12 volts was about 0.17 amps, and the maximum stall current at 12 volts was around 1.1 amps. The engine is filled with lead weights, and is pretty heavy for its size, but it only has two of its four wheels driving it and could only pull 6 cars before it started slipping too much to run. All the wheels pick up electricity, and they're spaced far enough apart that it doesn't have much of a problem with switches. The flanges are smaller than what's on most other Mehano engines, and should run through code 83 switches without a problem. The motor is completely isolated along with the headlight, so intalling DCC shouldn't be hard, and there's enough room in the top of the cab for a small decoder. I wouldn't recommend trying to install sound, because you'd have to take some weight out, and with this engine's drive, you need all the weight you can get.
AHM's Center Cab Switcher is a pretty cheap engine that can't really be compared to today's quality, but it's still a smooth runner that can get the job done, and with a little work can look as good as what you'd get today.
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