# Need help building a covered G-Scale bridge



## Sweet Dreamer

I'd like to scratch build a G-scale covered railroad bridge. The main thing I need are the dimensions to use for the open ends. 

I've decided to model my bridge artistically after the a covered bridge in New Hampshire name the Ashuelot Covered Bridge. I realize that this bridge is actually an automobile bridge. But there are many features that I would like to retain as I redesign this as a railway bridge. 










I'd like to retain the basic color scheme, along with the pedestrian walkways on either side of the bridge. I would also like to retain the lattice work along the sides of the bridge. I'd like to be able to see the train as it is crossing the bridge so I don't want a fully closed tunnel bridge. 

Here's another view of this bridge: 










I realize that for a railroad the bridge will need to be considerably taller. I may even place separate roof panels for the pedestrian walkways since they won't need to be nearly as high as the actual bridge roof. 

Here's a photo of an actual railroad covered bridge. I'm thinking of basically building a bridge similar to this, only with the open lattice along the entire sides and then with the pedestrian walkway near the bottom. 










*Two things I'm looking for right now are the following:

1. What size should I make the openings of the bridge to insure compatibility with most G-scale trains (I might end up selling a few of these bridges so I'd like to be sure they will work with most trains).

2. What size timbers should I use for the G-scale lattice work? Would 12" by 12" timbers be realistic? Scaled down to G-scale of course.  Or should they be smaller, like 10" x 10" or even 8" x8"? What size timers would a real railroad bridge most likely use?*


I'm having a hard time finding photos of covered wooden railroad bridges that have open lattice work on the sides. I found the following photo and these timbers look huge. At least 12" x 12" if not larger.


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## sjm9911

Verry cool! I have a few g trains , though not running them. I figure you could check out a manufactures site and see dementions. Im really no help some one will chime in! Good luck.


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## Big Ed

Have you seen this site?

I put a search for Covered Bridge and 250 came up.
http://bridgehunter.com/scripts/search.cgi?query=covered+bridge

I don't know if they will help you I don't have the time to look through the search right now.


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## Big Ed

Not to many come up in a Covered Railroad Bridge search,
http://bridgehunter.com/scripts/search.cgi?format=simple&query=covered+railroad+bridge


Maybe something like this? Though a vehicular bridge, just add tracks?


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## Big Ed

You looking for bridge info the Bridgehunter site is the place to go.:smilie_daumenpos:

Home page (for those interested)
http://bridgehunter.com/


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## Big Ed

Note,

Most covered bridges are fully covered. 
Top and sides, though some had windows.
The first covered bridges were built to keep the snow off of the bridge.


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## Sweet Dreamer

Thanks for the replies. I'm finding a lot of covered bridges for cars. But most of the railroad bridges I find are just boxes. On my layout I would like to have a fancy bridge. I'm not too worried about being prototypical correct. My model railroad is a "Fantasy Line" anyway. 

Ed, the bridge you posted is pretty too. I can find a lot of covered automobile bridges that are pretty. But it's hard to find a pretty covered railroad bridge. 

In the meantime the main thing I need is the G-scale dimensions the opening. 

I found dimensions for a G-scale tunnel portal. It says 8.75" tall by 6" wide with an arched top. I can probably go with those dimensions and be safe.


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## johnfl68

For some more possible insight, search Google for "White Mountain Central Railroad covered bridge" under images there are a couple different ones for that bridge, along with more information if you are wanting to search more.

It was built originally in 1904 on the Barre & Chelsea R.R. in east Montpelier, Vt. White Mountain Central Railroad bought it in 1960, and over the next 4 years took it apart, numbered each piece, and put it back together near Clark's Trading Post near North Woodstock, NH.

The bridge now stands as the only covered railroad bridge still in active service.


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## Gramps

The recurring problem with G scale is that several different manufacturers use different ratios. There is 1:20, 1:22, 1:29, and 1:32. All run on gauge 1 45mm track. You will have a tough time with one size fits all if you are looking to sell these bridges. Also, I strongly doubt any railroad bridge would have pedestrian walkways. Good luck.


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## Sweet Dreamer

Gramps said:


> The recurring problem with G scale is that several different manufacturers use different ratios. There is 1:20, 1:22, 1:29, and 1:32. All run on gauge 1 45mm track. You will have a tough time with one size fits all if you are looking to sell these bridges.


Yes, I see that's a serious problem. I'll guess I'll just have to say what dimensions my bridges are instead of calling them "G-Scale" since it appears to be an ill-defined scale. I might go with the 1:22 scale since I think that's what my trains are. 



Gramps said:


> Also, I strongly doubt any railroad bridge would have pedestrian walkways.


Yes, I understand this and realize that I'll have to design my own.


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## Navarre

You might want to look at the NMRA standards for clearance. 
Have not looked at G Scale, but they have standards for everything else. 


Sent from my iPhone using Tapatalk


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## Gramps

I hope it's OK to post this information here.
I have been away from G scale for several months but there are several G scale forums you could try. Large Scale On Line aka My Large Scale, Aristocraft, and Large Scale Central. Google them and you will find great information. The problem is there is no standard G scale ratio as there are in other scales.


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## Lehigh74

I think Navarre has it right. I would take a look at NMRA standard S-7 for the clearances.


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## Sweet Dreamer

Lehigh74 said:


> I think Navarre has it right. I would take a look at NMRA standard S-7 for the clearances.


I just looked at the NMRA S-7 Clearance Standards

Apparently Gramps is right. There are many different "Large Scale" sizes. 

The NMRA lists the following:

1:20.3 scale, they are calling F Scale
1:22.5 scale, they call G Scale
1:29 scale, they list as a recognized scale but don't give it a scale name. 
1:32 scale, they are calling No. 1 scale. 

I think my Bachman trains are 1:22.5 scale (what I considered to be the standard for G-scale)


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## Gramps

The G scale community refers to all those scales as G scale that run on #1 gauge(45MM) track.


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## Sweet Dreamer

​


Gramps said:


> The G scale community refers to all those scales as G scale that run on #1 gauge(45MM) track.


That explains a lot. I just read the "G-Scale" page on Wikipedia and they explain a lot of how the different manufactures created the different scales but all used the same size track. 

This is actually quite interesting for me.

I'm building an outdoor "G-scale" model railroad. And I actually think of the G as referring to "Garden Trains", since I'm basically building this around my landscaping gardens in my front yard. 

In any case, I actually decided early on to build all my buildings, cars, and people using 1:32 scale models. I wanted to stick with a single scale for the main scenery and dioramas. I chose 1:32 scale for several reasons, one of which is because it will allow me to do what I want to do within the space of my gardens. A larger scale like say 1:24 would be a bit large for the area I have to work with. 

My current trains are Bachman "Big Haulers" which are indeed 1:22.5 scale. But I'm hoping to eventually replace these trains with my own home-built trains. And I would actually like to build my trains in 1:32 scale to better match my dioramas. 

Apparently I'll be able to do that and retain the same size track the whole way through. That's makes it really nice. 

In the meantime I'll need to build this covered bridge large enough to accommodate my 1:22.5 trains. 

If I put any up for sale I'll just say that they are 1:22.5 scale, and call out the actual dimensions. That way I won't need to worry about calling them "G-scale".


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## Gramps

G scale is unlike all the others because of the different sizes. If you are modeling standard gauge then 1:32 is in proportion to the track size. 1:20 and 1:22 are roughly in proportion to some narrow gauges. 1:24 is half inch equals 1 foot and 1:29 is exactly 3 times HO. It gets really crazy when you try to find buildings and automobiles to match your size.


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## T-Man

There is a Covered Bridge Museum in Bennington VT
Google Image "Covered Bridge" to get some ideas.


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## Dennis Rayon

Just remember to count for your track height, around 1/2" tall
I would make it at least 10" tall and 8" wide, that way more of your work will be visible from the ends.
1/2" to a foot is an easy scale to model in. Anything close to that will work, This job would be much easier with a pinner, headless pinner prefered. only Grex makes 3/8" pins, so if you use 1/2" pins you will need to plan around pinning two pieces together.
Good luck and please post pictures
Dennis


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