Minding the Gap

Visitors to our train room will encounter the front bridge before they see anything else on the layout. With this in mind, I wanted to be sure the bridge made a grand statement in order to draw spectators immediately into our train world.

I formulated all sorts of plans involving an intricately latticed structure we would build from scratch. Our bridge was going to be such a towering example of artistic achievement, that even the most finicky modelers in the world would be impressed by our attention to detail!

And then I went to our local hobby shop.

I had gone in looking for a humdrum section of straight track, but a display of the magnificent 2-track steel arch bridge currently being manufactured by MTH caught my eye. The bridge is absolutely gorgeous and, when the two matching approaches are added, it is exactly the right length for our front bridge. At $75 for the bridge and $20 each for the approaches, the price was right, too.

With the two matching approaches, the MTH bridge was an almost perfect fit for our needs.
I removed the faux stone supports from both the approaches and the bridge and attached the entire
structure to the wooden span I had cut. The result was exactly the kind of grand piece I wanted
visitors to see upon entering the train room.

At first, I experimented with a hinged design for the base of the bridges. I was thinking that a hinge would allow the bridge spans to be lowered into place relatively easily. However, a little experimentation proved that raising and lowering a full 52” span anchored by a hinge on one side was too unwieldy. Being able to pick up the bridge span with both hands in the middle was a much more workable approach.

In addition to supporting the roadbed, I also wanted the bridge bases to do 99.9% of the work in aligning the tracks.

Pegs were made by cutting a pine dowel purchased at our local hobby shop and
setting them into two holes drilled halfway through the bridge base. Two pine 1x2’s were added to
the base provide to extra stiffness. I beveled the ends of the 1x2’s for appearance purposes.

To accomplish these goals, we went with a simple mortise and tenon approach. While I wasn’t up for carving square mortises into my table’s side frames, we were able to come up with a design featuring two large pegs that slip into corresponding circular mortises that are attached to the sides of the table. Another advantage to this design was that the bridges themselves provide additional structural strength to the two main tables once they are pressed into place.

I used the pilot holes drilled in the bridge bases to line up the larger holes that would receive the prongs. It’s always nice when the classic “hold your breath and hope and drill” works out just right on the first try!

A short scrap of 2x4 was cut to the width of the bridge, screwed to the side of the table frame,
and drilled with two large holes to receive the prongs from the bridge.

The pictures don’t show it very well, but our layout actually consists of a 4x12’ table next to a 4x11’ table. There is a doorway at the 12’ mark on the left side of the room, and I didn’t want to bring the left table all the way to the edge of a high-traffic walkway. I angled the edge of the left table in a trapezoidal fashion so that the front bridge rests at a natural angle between the two tables.

Before screwing the MTH bridge onto the wood base, I mounted
everything to make sure we had a nice, snug fit.

While the visual effect of the angled table is pleasing, the result was that there was a ton of extra track-cutting to do because of the odd shapes. You can see this angle by counting the few extra O72 curves just above the bridge as well as in the beveled edges of the small 2x4’s screwed to the edge of the table frames.

After the bases of the bridges were taken care of, we turned our attention to attaching the bridges and laying track. The first issue one faces in building removable bridge spans is how to deal with lining up the tracks on the bridges with the tracks on the tables.

I took a close look at the ends of the tracks on my 313 Bascule Bridge and noted that Lionel accomplished this by simply flaring the ends of the tracks on the bridge so they could be dropped directly down onto the receiving track pins.

I flared the ends of the tracks on the bridge by grasping the rail ends with a pair of track pliers
and gently rounding out the ends of the rails with the largest screwdriver in my toolbox.
Please note that only 50% of the books shown in the background are train-related...

Even with the rail ends flared as wide as I could comfortably make them, they were still a difficult fit over the track pins on the table. To make things easier, I tapped the pins almost all the way into the rails. The pins still provide an essential alignment function, but no electricity will be conducted through the likes of these...

Before mounting the track, I had to screw in a piece of lath to bring the track up to the
height of the MTH bridge. All of the scuff marks and cardboard shims under the lath were later
touched up with the same green paint used to paint the tables.

After everything was assembled, the bridges could be installed by lining up the pegs and simply pressing them into place.

The finished product looks like this...

The #3482 Milk Car was used extensively for testing purposes.
We needed this car to make sure that the pickup shoes on an older Postwar Lionel
piece of equipment wouldn’t bump into anything on the bridge-to-table connection.
We also tested the track by using an MPC 8030 IC GP-9 (with an extremely light
pilot truck), as well as the lightest MPC flatcar in our collection.

The final front bridge is shown at the top of this page. I am extremely pleased with both the bridge’s looks and performance.

Because we live in Bristol, Rhode Island, we decided to model the rear bridge on the Mt. Hope Bridge. The Mt. Hope Bridge is located just a few miles down the road from our home and connects Bristol with Aquidneck Island (i.e., where Newport, Rhode Island is located).

The toll booths on the real Mt. Hope Bridge were removed in 1998.
Since our bridge will be a railroad bridge, we won’t need them anyway.

Even though the Mt. Hope Bridge only handles automobile traffic, we though that putting a recognizable model on our layout would add a nice local touch. In real life, the Providence, Warren & Bristol Railroad had its terminus near our home. Passengers traveling from Providence to Newport would disembark from the train in Bristol, take a trolley to the point where the Mt. Hope Bridge was constructed, take a ferry across the bay, and then complete their journey to Newport by trolley.

Our model of the Mt. Hope Bridge is not complete at this time. (For more detail on the real Mt. Hope bridge, please follow this link.)

The reason why the Mt. Hope Bridge model wasn’t finished, was that we had an awful lot of track to clean and install...