Just a few more pics of the pin-connected deck truss at MP 49.7 of the former Coquihalla sub. As posted below, this is the bridge standing between me and being able to complete the first level of my Coquihalla scene and run some trains. And of course, it is a serious piece of engineering. For bridge lovers, it’s a visual feast: box girders, laced box girders, stringers, eyebars, pins, you name it it has it.
Above I did a drawing on computer, trying to rationalize it and understand how its components went together before attempting a model. I wanted to figure out precisely what supported what, how things interconnected, partly for my own interest but also of course to dictate how assembly would work.
Unfortunately this is one of those situations where HO scale is king and the limitations of N scale become painfully apparent. First, they do not sell any laced box girders of the type seen on this bridge in N -scale. They do in HO, of course, but not N. Initially I was going to fabricate something myself, and had been, using a styrene ‘box girder’ (minus the lace) as my model, I had been casting the legs one at a time using Alumilite. The plan was to affix lace to them afterwards. Unfortunately, that plan fell victim to the reality of trying to manipulate lace that is so tiny and fragile it’s almost impossible to manoeuvre. I tried some etched brass lacing (X shaped rather than W, the plan being to cut the Xs in half to arrive at a W shape) from Gold Medal Models, but even it was the wrong angle, too big, and too unwieldy. Cutting it to make the W wasted half the lace and warped the other half. So that died. I even tried making lace myself using the contraption pictured above. I pictured sliding up my bridge legs in a measured way and then affixing a dab of glue, sliding in some thin styrene strip, cutting it, then on to next, creating a series of / / / / / down the bridge leg one way, before flipping it and going the other way. Nope.. nothing doing. N-scale Fail again – it is impossible to glue with sufficient strength and accuracy when you’re dealing with pieces that small. Too often glue went where it shouldn’t, and the lace got stuck to the jig. Scratch that.
So now it looks like we’re going for the ‘best we can do for now’. N-scale is unlikely to ever have the array of options HO does, but there is a truss bridge kit made by Central Valley with some laced girders I can cut to the right size. The lace pattern and style is not correct, but, what other option is there?