Cutting in bridges

[jwar]

I am about ready to install about six HO bridges and could use a few hints before I start.

Of course I will secure both ends for vert alignment. I have noticed various model photos that some look better then others, using the same bridge. Other then weathering what precautions are in order.

The bridges I will use are
Girder, double main truss, warren, chord 36 in. I will build a wye tressle latter this year.
Thank you for info and have a great day....John

[Anonymous]

i would suggest putting guide rails inside of the main tracks

[cacole]

We have many bridges on the Cochise & Western Model Railroad Club's HO-scale layout, from Atlas, Walthers, and Miami Valley (redwood kits). I used Atlas flex track through all of them and have had no problems. In some of the bridges, the track had to be tacked in place with clear silicon adhesive, and in others, specifically the Atlas curved girder bridges, the track is just sitting loose. As JPM335 suggested, put guide rails in for a more realistic appearance. I used N-scale rail for this, glued in place with CA.

[bogp40]

There are many variations for installation. You need to consider the track support before cutting the roadbed, usually a pine riser positioned just behind the abutment is common. The ones I install on the club layout are anchored by the rails. Since we use pine spline w/ handlaid or flex, the bridge rails extend a few inches out over the road bed and are spiked to wood ties. Alternative to this is to use rail joiners- not as attractive but is a commom practice. These methods will allow for removal if ever necessary. When figuring the abutment/ bridge support, notch or laminate the shelf for the bridge shoes. If your bridge doesn't have shoes or not detailed enough this is the time to add or change them. The shelf height is critical for support and alignment. Many times I cut the shelf in 3/4 pine that is shaped to the exact dimension for the abutment allowing for the stone/ concrete plaster castings. this is also the time to position any supports for wings and retaining walls. Just make sure to double check your dimensions- draw out 1 to1 detail drawing if needed, and use care when cutting the subroadbed/ track especially on a curve. There may be hidden tension that can spring everything out of whack. I don't know your type of benchwork and track/ roadbed so this is somewhat in general.
Good luck, have any questions do ask in another post.
Bob K.

Cacole,
I really like that idea for the guard rails- It must give a real good prototypical look to the track.

[jwar]

Thank you both for the valuable information. Will put in the guard rail and bought some bridge shoes.

I really think my main problem was gettin over center as procrastionationnnn of messing with fairley decent track slowed me a tad. With your help I got on with it and with that...my hats off to you guys.

Your were right about cutting a curve. The second one did not hqve a chance to move. LOL.

What I really enjoy about this hobby is the people involved, trully making this a great pastime...Again...Thanks,....John