# The Knackered Valley Railroad. Part 4. Arch Bridge



## backyardRR (Aug 14, 2012)

One of the last major pieces of my initial Phase I loop was spanning a "gulch" that I had dug in my backyard. I had built the bridge last year so there would be no delay when the actual installation was ready. Basically a PT wood frame held together by galvanized brackets.









Side view with track.









I hot glued styrofoam sheets to each side and cut out the arches.









Styrofoam sides before stone details.The bottoms of the arches were precut and hot glued also.









Using a pencil tip soldering iron I carved stones into the styrofoam.









Here is the bridge after painting with acrylic paints. I added the random stone highlights to create a contrast.









Test fitting the bridge.









Side view of the test fitting. The 2 central piers will be supported by paver base and pavers. The whole area under the bridge will be lined with weedblock and topped with pond stone.









Final placement of the bridge. Since this is outdoors I have to take the terrain into consideration. PT wood and stone retaining walls will hopefully keep the dirt and rocks in their place. I guess I'll find out with the first "gully washer" rainfall.









Some more views of the final installation. 


















The far end of the bridge. The next step is the last 10 feet or so of track. I have already built the sub-roadbed up to the bottom end of the bridge.









Two views of the treatment around the bridge. Note that I am experimenting with precast stone retaining blocks along the sides of the gulch. Still more to come. The gulch actually runs to the covered bridge shown in earlier posts. 


















There it is! The home stretch. At least for phase I and the complete loop. I little cutting and fitting of track and it's time for the golden spike!









First run across the bridge with my Bachmann Forney and a freight train. The "S" curve leading into the bridge has been a non-issue, even with my JS passenger cars. More stone will be added to cover the bottom of the piers, etc.








Until next time. Cheers.

Wayne


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## Totalwrecker (Feb 26, 2009)

Looks great and was a faster way of constructing than building forms and casting in place. 

On site we tend to have warnings to cover all instances, though longer, your J&S cars are 'conventional' in that your trucks are closer to the car ends.. More modern stuff may have the trucks moved towards center which on our hobby curves, tend to push the couplers over the rails. On an S curve you can see where couplers take a beating as their car ends go in opposit directions, hence the one size fits all wraning(s). 

Thanks for sharing your progress, we all need some motivation, some times... 

John


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## backyardRR (Aug 14, 2012)

One thing I hadn't thought about was the overhang of equipment at the end of curves. This issue was discovered during test runs of various combinations of equipment. My Aristo covered bridge starts at the end of a 8' diameter curved section and the LGB marker lights on my caboose and observation car were hitting the inside of the bridge opening. A little work on the bridge with a Dremel tool solved that problem. Being a long time HO modeller I was not expecting scale issues in G scale. The LGB marker lights looked good when I ordered them but turned out to be a bit large and out of scale for the rolling stock. This just made the clearance issue worse. Fortunately, unlike my HO modeling, I am looking to achieve just an overall feeling for the era so it really doesn't bother me much. I can see why some other people really get p***ed off by these scale issues. Learning curve.


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## tmejia (Jan 2, 2008)

That's a great looking bridge.









Were the bottom (underside) of the arches one piece?

Does the bridge flex at the galvanized brackets?

Tommy








Rio Gracie


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## backyardRR (Aug 14, 2012)

Thanks Tommy.
The underside is more or less 2 pieces for each arch. I tried using 1 piece per arch but the styrofoam just didn't want to bend that much without breaking. I used silicone caulk to fill any gaps.
The bridge is very rigid and does not flex at the joints. Curious to see how it holds up through the Winter. Not a big $$ investment if it doesn't. Never had to worry about that with HO indoors ;-}

Wayne


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## backyardRR (Aug 14, 2012)

Those %$#!!& out of scale (at least vs. Bachmann) LGB marker lamps.
At least it was easier to get the LEDs into them



























Wayne

Knackered Valley Railroad


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## Jerry Barnes (Jan 2, 2008)

Nice job! I did mine with the blue construction foam. I guess if the white is all painted it should hold up to the suns rays. My problem with it, some critter eats on it. Suspects are ants, birds or squirrels. I did layer some vinyl patch cement on the top and that stopped it some, but that is now disappearing. Sorta need a new bridge anyway!


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## backyardRR (Aug 14, 2012)

It's all a part of my G scale learning curve. We have plenty of those grey squirrels here but hopefully they will not bother with the KV real estate. Ants could be an issue. I hear that Carpenter Ants (which we have had from time to time) like to borrow into those foam forms used to pour foundations. Not too concerned about the >=4 legged critters. It's the 2 legged ones that I worry about.

Wayne


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## dieseldude (Apr 21, 2009)

Wow! Really nice looking bridge. Great job and thanks for sharing. I did a similar type of bridge a couple of years ago. I used blue foam, like Jerry did. Haven't had any critters eating it, yet. I did try to coat it with sifted hydraulic cement (read an article about it in GR magazine). Not such a good idea. The cement cracked as soon as I tried to install the bridge. Live and learn. Keep up the good work. 


-Kevin.


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