Dutton Bay Tramway

DBT Benchwork - Modified L-Girder

The benchwork on the DBT, which is all there is of the permanent layout at the time of writing (July 2000) uses a modified form of L-Girder construction. Two modified forms in fact. On the left we can see the "removable" girder approach. This is used for station yards (in this case, the location is Warunda, where the wiring, switch machines and other complicated under base-board "gubbins" can be done with the board standing on its side. No need to crawl under the layout with a soldering iron. Notice that all bracing is attached to legs, rather than the girders, and that the weight of the girders is taken by a bearer, screwed to the legs.
Sitting on the framing, stored out of the way for the moment, is "corner board" from the exhibition layout.

Here we see another view of the removable girders. The bearer is quite clearly visible, as is a diagonal strut between the girders. In traditional L-Girder benchwork the girders are screwed into the legs, but in order to provide some stability there needs to be joists and diagonal bracing within the girder itself. The joists attached here are temporary, and will be replaced with others more suitable for the height of the Warunda board during that stage of construction.

Here you can see me lifting the girders from the leg structure.
After trackwork, wiring and (possibly) switch machines have been installed, this portion of the layout will be "scenicked" in. It is not meant to be a portable module, but will obviously assist in any future changes of location.

This is the benchwork which will support the station of Kelvin. Since Kelvin is an existing set of modules, for the exhibition layout, there is no need for "removable" girders, as the modules themselves can be removed. In this case the top surface of the girders support Kelvin at the correct height. The girders are attached to the legs in the traditional way, but there are no joists above the girders.
The structure deep in the corner, clamped to the framing in this view, will be used to add six inches of depth to the Kelvin scene. The main reason for the increased depth is to allow for a curved backdrop to be installed in the corner - even if the curve needs to be just 6" radius.

Another view of the Kelvin corner. Note the two small modules sitting on the framing, resplendent with white plaster in clear view. At an exhibition the viewers are on the opposite side, wherre the fascia board is located. One of the tasks to be completed in the conversion to the permanent layout is to attach a fascia to the inside of the layout.
The sundry tools (and bottle of "refreshment") are standing on L-girders assembled for the next module, which will support Saltpan.
The curtain material, used when the railway is exhibited, has been attached to the framing here just to see the affect. Even 10 inches too short for the higher benchwork, the appearance is good enough to convince me to add a curtain to the permanent layout later.

This is the Fiddle Yard framing. Once again it uses removable girders, but this module has had joists attached ready for the MDF board.
You can see a couple of fibreglass insulation "batts" lying underneath the framing. These are intended to be used to insulate the door of the shed.

Last updated 7-Jul-00

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	The benchwork on the DBT, which is all there is of the permanent layout at the time of writing (July 2000) uses a modified form of L-Girder construction. Two modified forms in fact. On the left we can see the "removable" girder approach. This is used for station yards (in this case, the location is Warunda, where the wiring, switch machines and other complicated under base-board "gubbins" can be done with the board standing on its side. No need to crawl under the layout with a soldering iron. Notice that all bracing is attached to legs, rather than the girders, and that the weight of the girders is taken by a bearer, screwed to the legs. Sitting on the framing, stored out of the way for the moment, is "corner board" from the exhibition layout.
	Here we see another view of the removable girders. The bearer is quite clearly visible, as is a diagonal strut between the girders. In traditional L-Girder benchwork the girders are screwed into the legs, but in order to provide some stability there needs to be joists and diagonal bracing within the girder itself. The joists attached here are temporary, and will be replaced with others more suitable for the height of the Warunda board during that stage of construction.
	Here you can see me lifting the girders from the leg structure. After trackwork, wiring and (possibly) switch machines have been installed, this portion of the layout will be "scenicked" in. It is not meant to be a portable module, but will obviously assist in any future changes of location.
	This is the benchwork which will support the station of Kelvin. Since Kelvin is an existing set of modules, for the exhibition layout, there is no need for "removable" girders, as the modules themselves can be removed. In this case the top surface of the girders support Kelvin at the correct height. The girders are attached to the legs in the traditional way, but there are no joists above the girders. The structure deep in the corner, clamped to the framing in this view, will be used to add six inches of depth to the Kelvin scene. The main reason for the increased depth is to allow for a curved backdrop to be installed in the corner - even if the curve needs to be just 6" radius.