Building Micro Engineering Viaduct/Bridge Tips

Model Railroader General Discussion (Model Railroader)
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Totally Thursday Tips Time!!!

Hello, I know I’m early but this is nice & I’ll be busy the rest of the week. I have always wanted to make a double deck display to fit onto a ‘Plate Rail’ in the house. One train on there was not enough. I got these Micro Engineering kits a while ago & looking them over I hesitated, but now I made it my mission to build a 6 foot single track viaduct to plant on that ‘plate rail’ trim. To do so I had to figure out how to get all the parts free without breakage, & how to assemble them without building in the warpage the kits came in. (Probably in a container in the hot sun…) So relying on my Public Television knowledge, (Red Green & Norm!) I made some jigs to help assem-bully [phonetic]. If you reference the attached picture, the legs are 4 pieces, the tower sides are severely warped into an ‘hour glass’ shape when put together. So, I made a jig out of appropriately sized brass tubing & clinched it in with basswood side strips, -to allow a tight fit & application of the ‘face’ ‘X bracing’ part. After a little dry time, it can be popped out & the rear part will fit nicely, on it’s own. I also made a girder assembly jig that allows the fitment of the sections & a nice ‘square’ base to tweak the fit of the parts before the glue dries. Much better than a pair of small carpenter’s squares taped to a board. As you can see in the pic, once the structure is assembled it is very strong, & I have 6 feet of it to do…
The kits used here are Micro Engineering’s “Single Track Viaduct”, “HOn3 50’ open girder bridge,” (same depth as the included 30’ sections!), & a brand new ootb Athearn KCS AC4400, & my modified Ath CN GP40. [Yes, a standard loco will fit through a straight shot of these, however, if a curve or other ‘wide’ accessories are on it, there may be big trouble, it is VERY tight. -Also, I will need to boost the height up with old computer keyboard key’s used as concrete pylons, the picture shows it sitting on 3/8" squ

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Chad,

I believe that a recent issue of MRR had an article by Tony Koester describing the build of a long bridge. One of our fellow forum members will know what issue. He started with a piece of aluminum channel and applied the bridge kits to it. If you want a 6 foot long bridge, I would recommend that method or you won’t have the strength needed. Keep us posted on your progress.

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Slammin, Say, Thanks!

Yeah, actually I read that one & I saw 2 videos on it, it is a very good idea, & a sturdy bridge as well.

In my case, these short spans, (even with the 50 footers) will be fairly supportive due to the short spans to tower ratio provided by the kit. I also considered laying in some ‘carbon fibre’ rod in the upper girders, but after building the test one in the picture, I deemed it would not be needed, it’s suprizingly strong. (the picture was shot with the tower legs fairly wet, -glued less than an hour) The CF rod would also add strength & be more of a hidden device as well. TonyK’s bridge was the larger (deeper) girder bridge, & I will use that technique in the future. This one I also want to keep as scale & airy as possible, as it will be a display unit & may not see variable use & stresses, as a working bridge would.

I appreciate the thought & comment, & I think Tony’s video is on here somewhere, I think (IIRC) it was a PRR bridge, but I can’t recall if it was fold down/entry unit or not… Either way, it is a good idea, it’ll never bow or snap…

Thanks,