Front couplers on MMI On3 models

swissboy Dec 16, 2009

  1. swissboy

    swissboy TrainBoard Member

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    MMI, for some stupid reason has mostly dummy couplers mounted in the pilots of their On3 models. The only exception that I know of, is the first model in the series, the K-27. It took more than a little while until I realized that that model has a functioning coupler up front. Particularly, since the first few models came without a tender coupler of any sort.

    I have now finally converted some of my models so that I can do double-heading trains. Thanks to the help from members over at the yahoo group, I realized that the conversion is not difficult at all. So far, I have two versions on my K-36 models. One got a Kadee, the other one a new SJCC Evolution coupler. The engines are seen front to front in the first picture. Personally, I prefer the looks of the Evolution coupler on the left.

    However, both couplers need some modifications for this purpose. For one, they both need to be shortened. Then, a hole needs to be drilled in the shortened shank for the attachment screw (well visible on both engines) to go through. The trip pin needs to be removed as well. Whereby care must be taken in the case of the Evolution coupler. It falls apart if one cuts the pin too close to the coupler as I had mentioned elsewhere ( San Juan Evolution? - TrainBoard.com post #9) . Unfortunately, shortening the shank destroys the function of the coupler. The shank contains the spring mechanism. So I had to fix the knuckle with glue in its closed position. I was concerned whether the glue would be sturdy enough. But today's test lessened my reservation. The second picture shows the test train with a K-37 up front, and the K-36 with the modified Evolution coupler in second position. Everything worked fine, but I had to lift the tender coupler of the front engine to couple with the modified coupler.

    No such problems will be encountered with the Kadee coupler. But it needs a small plastic insert in the front of the shortened shank to make it even.
     
  2. swissboy

    swissboy TrainBoard Member

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    Here is the more important one of the missing photos that were mentioned in the above post.
     

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