I would like to make a start this year on scratch building this bridge.There are lots of online photos but I have no idea of the dimensions of the steel. Is there a way to figure this out by looking at the photos? I am most interested in getting the arch dimensions close and can estimate the rest.
http://www.soultones.com/postcards/ByronHarmon/rppc/200/0238c_StoneyCreekBdg.jpg
Brent
Here is how I would go about it. If you know the length of a particular object in the photo, let’s say a passenger car you can do a little math, measure the details and come up with some ratios. Another way is to contact the railroad’s historical society and see if they have plans on file.
Many of the dimensions of this bridge can be found on figure 25 of the Arch Bridge chapter in the Bridge and Trestle Handbook by Paul Mallery. I think Carstens Publications sells this book. The dimension shown for the length between the ends of the lower arch is 336 feet. The vertical distance from the ground (as defined by a straight line between the ends of the lower arch) to the bottom of the lower arch is shown as 80 feet 9 inches.
There are 16 panels in the arch. The panels are the openings in your picture on the side of the bridge that are separated by the dark colored vertical lattice members. The drawing shows that all of these vertical members defining the panels are on 21 foot centers.
If I’m interpreting the drawing correctly, the width of the structure supporting the track is 19 feet. The width between the two arches at the base is 43 feet, again if I’m understanding the drawing correctly.
The book indicates that this bridge if built to N scale would be approximately 2 feet, and if built to HO scale would be approximately 3 feet 9 inches.
The book drawing has some detail figures showing the different structural members. I’m not sure that there is all the information that you’ll need, but it will eliminate some of the guessing.
Regards.
Thanks Maxman. I had no idea it was in that book. I will get my hands on one as I see it is readily available. I can estimate the rest through comparison measuring.
Brent
Just so you know, the sketch in the book is only a partial drawing and has some section views. It only occupies a portion of one page. If you are looking for a complete plan, this isn’t it. I don’t want you to be disappointed.
On the other hand, the dimensions they do so are far better than guessing from the length of a passenger car that is shown in 3/4 view on the bridge.
Good luck.