# Wooden Arch Bridge, sneak preview



## xo18thfa (Jan 2, 2008)

As a long-range project, I want to build a portable live steam layout. The track plan has room for two bridge modules, each 48” in length. Wanted to do something a little different so, I found a couple of nice wooden arch bridges doing a “Google Books” search. I did not get the name of the book, just downloaded the drawings. Both are light rail bridges, which I believe are French streetcar bridges. Not sure exactly which one I like best, so decided to combine features from each. The originals have double tracks, but this one will probably end up as a “gauntlet”.

Here are the two ideas. The original files are huge so I edited them down to save space.

http://1stclass.mylargescale.com/xo...ea%201.JPG

http://1stclass.mylargescale.com/xo...ea%202.JPG

Got started on it a couple of weeks ago and finished assembly of the first arch today. Each arch has 229 wood parts and 120 metal. There are four arches total. Got all the parts cut up, jigs made and figured out an assembly technique. Turned out nice and incredibly strong:




























Also got the handrail assemblies done. 



















More progress to follow.

Thanks and take care, Bob


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## Grimm (Oct 5, 2009)

Excellent start! It will be nice to see the finished bridge. Are you going to stain or paint it?

Jason


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## altterrain (Jan 2, 2008)

Nice work. It should keep you busy for the winter! Looks strong enough to sit on. Is it made from pine? 

-Brian


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## Bills (Feb 20, 2008)

First class wood working! Keep us informed


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## lownote (Jan 3, 2008)

That's really marvelous work! Getting all those angles right--really impressive. Please post updates. That's a unique and really fascinating idea


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## smcgill (Jan 2, 2008)

Were you a cabinet maker in another life? Looks awesome !


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## Dwight Ennis (Jan 2, 2008)

Looks terrific Bob! Nice job!


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## jimtyp (Jan 2, 2008)

Amazing Bob! Looks Fantastic! Thanks for the links and close up how-to photos! I'm constantly amazed at how fast you build such great looking models. 

How do you do all those small parts so fast and consistent? Do you have a CNC machine?

Please keep posting your progress  I would love to see the final bridge. 

Have you figured out what you will do for the abutments? 


Is that plastic or wood you are using?


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## Cougar Rock Rail (Jan 2, 2008)

Wow that thing is gorgeous--what a work of art. It will be spectacular when it's done! 

Keith


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## Jim Francis (Dec 29, 2007)

*Bob, that bridge looks fantastic!*

*Looking forward to seeing the finished project!*

*Jim*


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## xo18thfa (Jan 2, 2008)

Thank you all very much for the kind comments and words of encouragement. Parts for the other 3 arches are cut out and ready to assemble, but it looks like "Honey-do's" for the next few days, back on it later next week.

Jason: I don't know what the finish is yet. Had not thought of paint. Now that's an option too.

Brian: The arch members are pine laminates. 3/4" x 1/8". Six on the bottom and five on top. All the cross braces, middle spreaders and angle blocks are maple. The hand rail is pine cross pieces and cedar for caps. So far, this project is from leftover lumber stock. So whatever fits goes in. The tie rods are 4 x 40 threaded rod. 


Lownote: There is a 1 3/8" gap between the two arches. You would think that the angle blocks between the cross braces would be close to the same. They are not. The lowers are 21 degrees and the uppers are 27. I went thru the math three times.


Jimtyp: There are some little tricks to cutting identical parts on the table saw. Once you are set to cut one part, you can cut a million. Same on the drill press. The abutments on the original appear to stone of some kind. The plan is to build them up from wood and paint with that rattle can stone paint from Home Depot. Guys here in the modelmaking forum say the stone paint works well and looks good. I will give it a try.


I've taken several in-progress photos. I was thinking about posting more photos in the next few weeks.

Thanks again to all, Bob


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## SteveC (Jan 2, 2008)

Bob

Don't know if you're aware of it but the max width of posted images has been increased to 800 pixels. Hope you don't mind I took the liberty of changing the display size of your above images to the new max.

As usual that's some mighty fine modeling, it's going to be one heck of a bridge when you're done.


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