Question about clearance.

[Del Monte]

I'm in the process of dismantling an old 5' x 9' layout that I constructed when I was a teenager. Plans have all ready been selected for a simple double folded dogbone style with serveral crossings and turnouts. The interest here will be lots of moving trains with detailed landscaping. Hopefully it should be 13' x 6' overall when it's done. My biggest question is, is it possible to have two side by side wooden trestles in one of the outer loops? By outer loops I mean the inner loop is a 18 degree radius and the outer a 22 degree radius. My plans would be to use possibly two of Campbell's #304 kits to span a wooded gourge. But looking at the current plan I'm not sure if the trestle bents will sit next to each other given the width of the bents at the base. Would it look alright to stagger the trestles so they would have clearance or should I go another route? One more question. What is the best way to determine the depth of the gourge when I construction that portion of the layout? Thanks for any help.



Del

 

[jetrock]

Kind of tough to visualize without a graphic...

 

[Fred_M]

If the railroad had ever build such they would of done both tracks on a single wider trestle. You may have interference problems too. That being said, it's your railroad, do as you please. It might actually look wild if you somehow interlaced the trestles in a complex matrix. When I was thinking of doing something like that I had thought to keep the smaller radius inside the mountain the trestle was hugging and only model the outer track on a trestle. That would be more prototypical as very few bridges have double track, and I never ever seen a double track trestle (real). There is a saying that there is a prototype for everything, but I'm thinking not this time. LOL Fred

 

[cidchase]

Hiya Del

Fred's right, I believe, side-by-side trestles would be a rarity.
Double-tracked trestles seem fairly scarce, too!!
I found a couple:

http://www.wmwestsub.com/mccoysferry.htm
(old pic)

Kate Shelley High Bridge. The longest and tallest
double track bridge in the United States! Boone, Iowa
(new pic)

There are side by side trestles on the TVRM line at Chattanooga. The NS (?) trestle was built much later and is higher. They are probably 200' apart.
(If memory serves.) :thumb:

http://dcnr.nv.gov/markers/mark_100.htm :
Mark Requa's Nevada Consolidated Copper Company built a 150-mile
line from Cobre on the Southern Pacific to Ely in 1905-06 to haul
ore from Copper Flat mines west of Ely. Ore was loaded into railroad
gondolas at Copper Flat for the trip to the smelter at McGill, over
a double-track trestle 1720 feet long. The trestle burned in 1922
and was replaced with an earth fill.
(no pix found) This must have been a sight!!

 

[Del Monte]

Thanks to all. And thanks for the pics they will be good reference. Dash you brought up a go point. I also was wondering if the inner track could be routed through a tunnel or a mountain side cut. By my measurement the centerline distance between the two tracks is about 4 inches. As far as a graphic you will have to check out the atlas track web site and look at HO-10022 under the HO layout link. Sorry it's not a hand laid rail setup. I'm a true sectional trackage man. But I will be opting for the code 83 this time. One more note about the layout, it will be flip flopped end for end due to space issues. The loops I'm refering about are in the smaller end of the layout. This raises one more question. Will flipping the plan change the direction of the turnouts?

 

[DWP]

As far as the trestles go you might want to look here
http://www.blackbearcc.com/
You can print out some of the plans to get an idea of height ect.
If you can use some flex track on the trestles part,
might look better.
Dave

 

[Doc Holliday]

Del,
I had a similar problem when I started. The attached poor pic shows the largest trestle on the far right. The trestle spans a lake which will extend to the left under the next two sets of tracks. Two more trestles will be added under these tracks. Originally, the right two lines were much closer together. I finally ended up re-aligning them to increase the separation to allow for the trestle base widths.

The height of my largest trestle was based on the highest I could get using 4% max grades. I cheated up by 2" by using a layer of 2" foam over my entire layout that will be cut out for the lake. The water surface will be directly on the plywood. I'm just finishing the other two trestles and will post some pics when I get them in place.
Doc

 

[Russ Bellinis]

Thanks to all. And thanks for the pics they will be good reference. Dash you brought up a go point. I also was wondering if the inner track could be routed through a tunnel or a mountain side cut. By my measurement the centerline distance between the two tracks is about 4 inches. As far as a graphic you will have to check out the atlas track web site and look at HO-10022 under the HO layout link. Sorry it's not a hand laid rail setup. I'm a true sectional trackage man. But I will be opting for the code 83 this time. One more note about the layout, it will be flip flopped end for end due to space issues. The loops I'm refering about are in the smaller end of the layout. This raises one more question. Will flipping the plan change the direction of the turnouts?

Prototypically, if the railroad could make a cut on the side of a mountain, they would make it wide enough for both tracks. There was an article in M.R. a few years ago on building an N-trak module based on a scene on the New Yoek Central along the Hudson River Gorge between NYC and Albany. The problem the N. Y. Central faced was a mountain that was solid rock down to the river's edge. They were able to blast a ledge in the rock for one track, but it was just too tall to make a cut for the second track. The solution to the problem was to blast a tunnel through the rock for the second track. If you want a trestle, the prototypical way would be to double track one trestle. I don't know if anyone makes a double track trestle, but you could pick up scale lumber in addition to your Campbell kit and "bash" it. Of course, the difference between building the Campbell trestle and building one from scratch is that the pieces are precut on the Campbell kit; so you might want to just build the whole thing from scratch with scale lumber.

 

[nolatron]

Not exactly a trestle bride I guess, but the Huey P Long bridge here in New Orleans is a double track spanning the Mississippi River.

See Pics here:
http://www.angelfire.com/la2/siresphotos/trains/no/hp/


http://nopb.com/

"The Huey P. Long Bridge, completed in 1935, is the longest and highest steel railroad bridge in the United States. It is 4.35 miles long from abutment to abutment. It is a combination rail - highway structure and provides a four-lane highway, two one-way lanes on each side of a double track railroad."

 

[Del Monte]

Nolatron, awesome pics! Doc I see you are using the styrofoam method. How do you keep it in place? Is it a stable setup? I guess I should also mention, I'm thinking of tunneling the inner loop and trestling the outer. Now I'm not sure if the wooden trestle is the right choice. When did the steel structures come into play. My plans are for the 50's era. Would the wood be better than steel or should I go with steel and be done with it?

Del

 

[Doc Holliday]

Del,
I glued the foam inclines and risers in place using Liquid Nails for Projects for Foam. Some guys use white or yellow glue or caulk. I used "T" pins to hold it in place while the adhesive dried. It is very strong. I had to pull up some of the foam to create the lake under the trestle and had a heck of a time getting it up. As for the dates for steel trestles, I' not sure. My guess would be steel began to become popular around the turn of the century. I'm using wood trestles since I'm way out west circa 1880 where steel mills were few and far between.
Doc

 

[RailRon]

Del, whether a wood or a steel trestle is right depends on the theme of your railroad.

In the '50s I think that no bigger RR company still would have constructed wooden trestles. However, if you model a little backwoods line (or even a logging line) in a landscape with rich vegetation (i.e. if there are enough trees around to get the needed wood!) , then a wooden trestle certainly is ok.

But most important is: If YOU love the sight of a big, beautiful trestle - by all means build it. After all, it's YOUR railroad, YOU are the CEO, and so YOU decide what belongs on your layout! Period! :thumb:

Ron