Bridge Layout and subroadbed depth

[Anonymous]

I am new to HO modeling and would like to add an appoximate 9" bridge spanning a swamp area in my layout. Once you cut out your subroadbed, how do you go from there? Are most available bridges easy to work with and how do you fasten to code 83 flextrack?[8D]

[eastcoast]

83 FLEXTRACK????? Most products I am aware of are code 100 track.
For 83, you need to find a product that is compatible with out a conversion
piece. For only a 9" span, the possibilities are endless on products. I am
quite more ambitious on bridges, mine are more than 3 feet long. I have 4.
Most of the bridge kits from Atlas are simple to construct.
To get the bridge at level, if wood or blueboard, extend subroad slightly into
area under bridge and notch out ends until all are level and operate without
problem before permanent install.
ken_ecr [:p]

[Jetrock]

A lot depends on the product--some bridges don't have track on them yet, the user applies it, while others use Code 83 (I've noticed it more and more) but Code 100 has been kind of the traditional gauge.

A swamp area? Would you want a bridge, or a trestle? Trestles are a more popular solution in lowland areas subject to flooding. Bridges are typically found under rivers or places where either there is a need to leave clearance under the bridge or it's impractical to sink pilings--in merely swampy or subject-to-flooding land, they'd build a trestle or a fill instead.

In general, when building a bridge, you'd place the abutments first, since, as with the prototype, it is the abutments, not the track, that hold up the bridge. You can then set the bridge on the abutments and attach it to the track with rail joiners or solder.