Interested in any ideas or thoughts about providing electrical continity to the track on a layout with a lift up bridge( providing walk thru access); also how to align track when bridge is in the down position.
This is what I have done.
I used a MTH dual bridge, it is a plastic bridge. I had a piece of sheet metal cut, and mounted the bridge to it. I used cabinet hinges for mounting, and reinforced the hinge plate with a simple L brackets. The bridge lifts up to about 110 degrees. When lowered the bridge does rest on the layout, the bridge is longer than the space needed for the walk thru area. I am using Ross and Gargraves track, I mounted the track directly to the sheet metal.
Initially I did NOT wire the bridge electrically, and relied on track pins for power. That worked fine for a year or two. The track pins I used are refferred to as “knife” blades, they are quite thin and have a beveled edge to which allows the bridge to close on the track connectors. Over time the hinge worked loose a little and the knife blade would short out occassionally.
About a month ago I decided to rework the bridge, and tightned up the hinges, and powered the track directly from the hinged side. I have retained the knife blade on the ground rails for alignment. The bridge works well.
I have a drop down section to enter layout. I used heavy piano hinge which does not allow right/left movement. After I got that completed, I installed track. I ran jumper wires from main layout to under the secton. Have to leave enough “slack” in jumpers to allow movement. Thinking of replacing this with a power lift up bridge I saw at York last year. One of the venders builds a nice one that works from “command”.
Lift or drop down, six of one half dozen of another, I will add one very important suggesstion “add a kill switch for when the bridge is not in the run position”. Peace of mind when you mite be doing maintenance or if you should have guests visiting the layout. [X-)]
For tubular track, spread the end of the bridge rail and reshape it into an inverted V with the apex rounded to match a track pin in the stationary rail. Support the end of the bridge on an abutment, not with the rails. Bend the last few inches of the bridge rails slightly downward, so that when the bridge is resting on its abutment, the rails are flexed back to their horizontal positions but pressing gently on the track pins.
At the hinge end, put the hinge pins vertically at or above the height of the railheads, so that the rails do not pinch together when you raise the bridge. If you locate the rail gap horizontally farther from the table than the hinge pin, the bridge rails will rise as you open the bridge; so you can make a V in the bridge rails just as at the other end. If you locate the gap closer to the table than the hinge pin, the bridge rails will drop as you open the bridge. In that case, make the Vs in the stationary rails and put the pins in the bridge rails.
Thank’s for the come back GUY’S. Never used the forum before & wanted to try it out. Good suggestion’s and as I proceed to that section of my layout I"ll keep them in mind. Back to the train’s, see YA!
Hey Bob; thank’s for your suggestion. I forgot when I first wrote my message that the issue of the track having clearance as the bridge was raised was my main concern. Tricky to picture in my mind but I"ll work on it.
Thought I would throw out a couple of other things to keep in mind when working on the plans for you lift/drop access bridge. The other posters so far have made the cross-country trek and visited our club’s layout so they may or maynot agree on this. If you look at the following photo you can see on the left side where we located a lift bridge:
The overall design and museum requirements left that as the only place where we could install a lift bridge. Unfortunately it is a curve and the structure is comprised of wood and or wood products. This made it rather heavy and subject to expansion/contraction with weather changes, the weight can be compensated for with gas struts but the other issue with the weather is a constant maintenance issue.
I have a walkway down from the start of a yard. There are about 7 tracks going across this bridge on one side. At first I had hinges on one side and when the bridge was down the tracks on it stuck upwards and I ran into tracks a few times while heading to the bathroom at night (this is a bedroom layout). Then I tried squared “U” shaped brackets and hanged the bridge on a board attached to the hinges. Finally I took it all apart and used the lightest thinnest plywood I could find. I cut it to shape and put it over the walkway, then layed the track on it. I screwed steel hardware handles to the top between tracks so installing and removing it is simple. I also bolted some “L” shaped angle aluminum to the underside to reinforce it. It is quite light and easy to work with. Both ends of the track I opened up into an inverted “V” like mentioned above before me. I wired all the tracks on the bridge together. I have been using some GM alternator extention wires from a parts store but they don’t work well. I will be replacing those with the ends of cheap 2 prong extention cords from Wal Mart. I think I paid 88 cents per cord. Make sure you wire the bridges using the male ends of the cords and the layout itself using the female ends.