Gnome Miniature Engineering
1335 West River Road
Cambridge, Ontario NIR 5S5
Canada
Prices: Girder bridge, $321 + s&h;
truss bridge, $338 + s&h
Website: http://gnomengineers.blogspot.com
Wood-and-aluminum bridges for garden-railway use. Plate-girder bridge (#PL36) dimensions: length, 36″; width, 4” (bridge), 6.625″ (timber bridge deck); height, 3.575″. Warren truss-bridge (#TR42) dimensions: length, 42″; width, 4.5″ (bridge), 6.5″ (timber bridge deck); height, 6.375″
Pros: Strong; well made; prototypical construction; can be used with a variety scales
Cons: None
garden railways. Two examples are reviewed here—a 36″ long, plate-girder bridge and a 42″ long, Warren truss bridge. Both bridges are made with aluminum plates and girders convincingly close to scale size. They are built using construction methods similar to those used on full-size bridges: each bridge is riveted together with solid aluminum rivets. Important structural corners on the truss bridges are held together with stainless-steel cap screws and are hidden from view. Wood decks, assembled with brass pins, are fastened to the bridges with aluminum strips and wood screws, which are also hidden from normal viewing.
The models are designed so that the customer can hand lay his own rails of choice directly to bridge timbers (the truss-bridge review sample came supplied with aluminum rail already installed for illustrative purposes). Alternatively, the customer could use commercially-made track to the tops of the bridge timbers.
Our review samples were supplied unpainted and unstained. The manufacturer informs us that the production bridges are supplied with stained wood and also painted in the customer’s choice of either red oxide, gray primer, flat black, or unpainted. A small etched-brass plate with “GME” (the company’s initials) is affixed to the bridge with rivets. I found this a nice touch.
Given the prototypical construction techniques and near-scale thickness of the aluminum used in the construction, I was somewhat skeptical about the ability of the bridges to withstand a heavy load, especially given that some large, 1:20.3-scale live steamers tip the scales at almost 40 pounds.
I set up a simple test rig to evaluate the strength and stability of the bridges under a heavy load. The bridges were set on a large, level, flat surface, supported at each end. I set up a dial test indicator (which can precisely measure distance) underneath to determine the deflection of the bridge load. I then added 45 pounds of lead weight to the center of the bridge. I was pleasantly surprised to see that the deflection at the center of both sample bridges was minimal (less than .030″) under this heavy load—a testament to how well the bridges were designed and constructed.
These well-engineered, well-manufactured bridges would complement any garden railway. Gnome Miniature Engineering will also undertake custom work, providing plate-girder and truss bridges to specific lengths, and in narrower widths for 0-gauge track.
