# Logging Suspension Bridge



## jkarns (Jan 5, 2008)

A few months ago I started my garden railroad, including pond and waterfall. In front of the waterfall I wanted a centerpiece bridge. To get running trains as soon as possible I built a quick-and-dirty 6 foot long truss bridge out of a redwood fence board and some plant stakes to span in front of the waterfall. This bridge was to be replaced with a Howe truss bridge, but after some research I decide to build a suspension bridge. Besides being a cool bridge (especially to a structural engineer), the reduced depth would be least obstructive to the view of the waterfall. The bridge is patterned after the Harter Brothers Lumber Co. bridge as seen on page 135 of The Climax Locomotive book (Oso Publishing). 

All of the lumber is cut on my table saw from redwood fence boards. I drew up the plans in Autocad (if anyone is interested in the plans I am willing to share), printed them out full size, and built the bridge components right on the plans . The suspension cables are 1/16” stranded cable, with the verticals soldered to the suspension cables. All joints are glued with Titebond III and pinned with 18 gage brads. 

Construction begins








The bridge being replaced








First train across



























Next; trestles. 

Jesse


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## plewitzke (Jan 2, 2008)

A truly unique bridge and you did a beautiful job of constructing it Jesse! I would be tickled to death to have the plans for it. Please let me know what I need to do. Thank you for sharing. 

Pete.


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## Jim Francis (Dec 29, 2007)

Jesse, That is one awesome bridge!


Could it be extended to span 8-feet?

Please contact me off list. 




Jim


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## Matt Vogt (Jan 2, 2008)

That is one beautiful bridge, Jesse! I, too, would appreciate the CAD drawings for future project. I'm assuming that since the cable is soldered, the cable is galvanized, instead of stainless. That should weather a lot more realistically.

Nicely done,
Matt


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## Steve Stockham (Jan 2, 2008)

Very nice! A unique design that really sets it apart! I _like_ it!!


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## Jerry Barnes (Jan 2, 2008)

Very creative, thanks for sharing.


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## Chrisp (Jan 3, 2008)

Awesome bridge - what is the span? Do the cables actually carry much of the weight?


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## jkarns (Jan 5, 2008)

Thanks for the kind comments. It is a unique design that isn't seen too often, and it was fun to construct. As a long time lurker, I learned a few things from the talented folks here on MLS. 
As surmised the cables are galvanized and not stainless. As far as functionality it is hard to tell. I designed the cables to take weight, but the structural mechanics don't necessarily scale very well. They are taunt. To answer another question; although the span as designed is 6 feet there is no reason it could not be expanded to 8 feet. 

As a side note: does anyone know if its possible to attach a dxf drawing file to a forum message? If so I could more easily share the bridge drawing. 

Jesse 
Long Beach, CA 
SA #283


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## SteveC (Jan 2, 2008)

Posted By jkarns on 03/16/2009 8:36 PM
_{snip...}_ As a side note: does anyone know if its possible to attach a dxf drawing file to a forum message? If so I could more easily share the bridge drawing. _{snip...}_
Jesse

Since you're a 1st Class member, just upload the '.dxf' file to your MLS web space and then place a hyperlink to the file's URL address in your reply. Then anybody can right click the link and download a copy. The problems with trying to use the _"Message Attachments:"_ option is a limit on file size of 60KB and an invalid file extension (i.e. .dxf).











The only problem that you may encounter using the MLS 1st Class member web space interface, is an _Upload Timeout_ error if the file size is too large or your ISP connection is too slow.

There is an MLS FTP interface available if you know how to configure an FTP client on your system and wish to use it. Do note that no anonymous login is supported.
[*] The MLS FTP address is...
1stclass.mylargescale.com
[*] The user ID that you use is your MLS User ID plus...
[email protected]
[*] The Password will be your normal MLS password.
[/list]


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## jkarns (Jan 5, 2008)

Does not look to be easy to download (or attach) dxf or dwg file. After uploading to MLS webspace, the dxf file is not recognized. Pictures work fine, but other files can not be opened. So, if anyone would like a copy of the bridge drawing please PM me and I will be happy to share it with you. 
Jesse 
Long Beach, CA 
SA# 283


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## John J (Dec 29, 2007)

Sacred Bovine. That is one great looking bridge. I like the abutments. They look great


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## jkarns (Jan 5, 2008)

Glad you like. The cribbing for the abutments ended up being one of the more difficult aspects of the bridge. The left one is on a sloping shelf in the pond and had to be shaped around a larger rock (once I set a rock I don't like to move them). I used gorilla glue and brads for the submerged portion. The abutments are filled with stone ballast which makes the bridge very stable. 
Jesse 
Long Beach, CA 
SA #283


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