Pier-2-Pier

At some point you have to commit, and I’d reached that point with the harbor scene. I’d researched the water sim, and I’d built the bridge piers and car float piers. There was a sense of urgency in that I couldn’t operate the layout while the bridge-building was going on. Time to press on.

I spent considerable time fiddling with the girder bridge sections. I found that a couple of things hampered the operation. The flex-track curve wasn’t constant radius, and that in turn made some unpalatable compromises necessary. I’ll take full responsibility for the curve problems, and any other complications: it’s not as if anyone else was doing this.

I realized that to get the bridge piers to hold position, I needed to add weight. I hit upon the idea of putting a clamp on the piers, and so add mass so they wouldn’t shift so easily. This worked fairly well. The piers stayed in place while I fiddled with the bridge sections.

Clamps holding piers 2

The tape is to hold the section in place while I maneuvered them about. You can see that the curve of the track doesn’t match the curve of the bridge. In order for that to happen, I’d have eight sections of bridge rather than four. Again, a compromise between realistic construction and visual appeal. It’s not prototypical, but is more visually appealing.

It was obvious that the pier supporting the girder section was key. Everything else would be laid off that. I located that pier, and then glued the girder bridge piers down with CA. I discovered that the middle girder bridge pier had to be re-laid. This was a useful lesson in that in future I’ll lay any two end piers, and then lay the middle one.

I’ve noted previously, but the usefulness of the Chinese-made clamps from the dollar store cannot be overstated. I bought six clamps for a dollar. They are enormously useful.

I’ll note that this project would probably be a lot easier if there weren’t previously laid track involved. Projects in the hobby press often tear out track, but while I could do that, I’d much prefer not to. A personal preference: with track in place I can run trains during construction.

I’ll also note that the construction of the piers (and subsequent construction of the wharf proper) is based on a book ‘Wharves and Piers’ written by Carleton Greene c. 1917. It’s available as a free download off Google Books. More info than you may want to know about the subject, but a very useful reference.

I positioned the girder bridge piers, and glued them in place.

Piers in place 1

At this point I’d positioned the abutment and three ‘wide’ piers in place. a A little arithmetic put the eight ‘narrow’ piers at 27.5 mm apart, so I drew lines with a square:

Pier lines 1

Then a matter of dabbing CA on the bottom of the piers and placing them on the grid:

Pier clamping 1

A little experimentation with the clamp holds the pier perpendicular to the surface. Overall, the process worked well. For horizontal alignment, I found that an MT box worked well:

Using MT box for piers

The box lines up with the outer edge of the abutment. As usual, it’s what I had on hand that would work.

A look at the piers in place:

Piers 1

Piers 2

After a final test fit of the girders, it’ll be time to pour water.

 

 

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