# Researching Our First Timber Trestle



## CapeCodSteam (Jan 2, 2008)

Greetings,

Tomorrow Doug and I start ripping wood for a trestle on the Setucket Creek & Far Fields ry. Right now I am looking for a good article or two that includes some general plans and detail photos, especially for the top. If anyone has any saved in their faves, I'd love to see them.


Thanks


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## Richard Smith (Jan 2, 2008)

Try here... http://members.cox.net/sn3nut/trestles%20part%201.htm[/b] On the last slash url I typed in " [" and it comes out " ;"


Doesn't look like links are working. Type in the address from your internet connection. Or...google it...type in..RGS Trestles
(Edited URL link, SteveC)[/i]


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## RGSNH (Jan 13, 2008)

try this one

http://members.cox.net/sn3nut/trestles%20part%201.htm

Al P.


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## CapeCodSteam (Jan 2, 2008)

That info was exactly what I was looking for, thank you.
The trestle in question will cover a seven foot span, approx two feet high. This is a double mainline, so the trestle will be two tracks. I have been looking and so far I haven't been able to find any pictures of a double trestle, and looking into trestle construction, I'm pretty sure no such thing exists in real life.

All the info I have found has the main vertical posts placed under the rail, thus supporting the load and the trestle. So instead of four or more posts, I have decided on a three post system. The center post will be placed at the mid-point of the cap, with the left and right posts being placed under each line for support. Below is a rough sketch, keep in mind the exact measurements will be determined later this week. The focus at this point is to finalize a design. Please take a look, tear it apart and ask questions.










Also, not shown on this plan are the stringers between the foundation and the 2nd sill, ran out of room


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## SteveC (Jan 2, 2008)

Kent

On the matter of double-track trestles, in the real world I don't think you'll find many that are over 25' in height. Over that they'd be made of iron/steel.

For some examples the following links are to H0 sites but they demonstrate the double-track trestle bent structure.

Black Bear Trestle Jig[/b] (scroll down a bit to see small diagram, then scroll on down to the 'Instructions' section and click the 'Page 2' drawing link)

Double Track Trestle Bent System[/b] (go to page 5 of PDF document)

Here's a book that may be of interest, I ran across it on Google Books and you can download a PDF format copy of it if you wish.

A Treatise
on
Wooden Trestle Bridges 
According To The Present Practice
on AMERICAN RAILROADS.
by
Wolcott C. Foster.
Third Revised and Enlarged Edition.
First Thousand.
NEW YORK:
John Wiley & Sons.
London : Chapman & Hall, Limited.
1904[/b]


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## Totalwrecker (Feb 26, 2009)

On your double wide, there should be vertical legs under each stringer and the the angled legs outboard of the track and you shouldn't skimp on the number of legs, if you want prototypical. 
Your stringers (on top of trestles) are too thin. They form a bridge between the bents aprox. 14', would you rather walk on a 8x8 timber, a 4x8 or a 1x8 across that gap? I made my stringers even taller as that is where the 'bridge' strength is. (mine is a glue lam spline). Look at the plans and you'll see 3 timbers bolted together for extra strength, don't skimp here, unless you want a toytrain look with bents attached to track. 
My biggest concern is making the legs of one single track bent carry the load of two. I'd omit the center legs as it supports nothing, have two true verticals under your rails and then two more angled in, on the outside. 
Search Eastern seaboard commuter lines for double trestles, out west distances were too great for double tracking between passing sidings.... 

John


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## Totalwrecker (Feb 26, 2009)

Steve C, 
Thanks for that link...The Treatise ...I got lost in there! In a good way! 
The artisan in me, likes the idea of the Author's that one wooden dowel is better than 2 iron bolts! 

John


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## CapeCodSteam (Jan 2, 2008)

Steve and John,

Thanks for your feedback. Doug and I spent the afternoon in the garden and the garage designing what became our first prototype bent for the double line trestle.

We started with a list of requirements, First and formost is strength. Doug, aka Papa, has five grandsons ranging in age from seven weeks to eight yrs old. That means seasons of balls, frisbies and other things boys play with and break things with. Next came the tape measure and a bridge reqirement of six feet in length and twenty inches high on the north side and eighteen inches on the south. Instead of a intricate scale trestle worthy of winning the monthly photo contest we decided to build something that resembles a trestle while being built way over scale for strength. Below is a picture of our prototype bent, they will be placed just over a foot apart with four large stringers lined up under each rail. I'm starting to think that when the whole thing is done, it would look more at home with 7 1/4' atop it rather than two 45mm lines. Who knows, maybe we'll upscale someday.










The whole bent is made using 1.25 x 1.25 cedar with 1.25 x 0.375 cedar for the sway bracing.

Back to work tomorrow, details to follow


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## SteveC (Jan 2, 2008)

I know you've already started on your trestle and don't really need this but it's seems to be a good reference work that I ran across.

International
Library of Technology

A Series of Textbooks For Persons Engaged in the Engineering
Professions and Trades or For Those Who Desire
Information Concerning Them. Fully Illustrated
and Containing Numerous Practical
Examples and Their Solutions

The Transition Spiral
Earthwork
Railroad Location
Trestles
Railroad Buildings and Miscellaneous Structures
HIGHWAYS
Pavements
City Surveying
City Streets
Construction Drawing

Scranton:
International Textbook Company
35B
1908


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## CapeCodSteam (Jan 2, 2008)

Well yesterday was a busy day, we have five bents made, have figured out the stringer hight and are now ready for the landscaping and stone work at the edges.

Here is a picture to give an idea.










I'm curious to see who will be the first person to point out the mistake in the picture. 

Enjoy


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## CCSII (Jan 3, 2008)

Your "parity is off." The second bent from the left has its parity reversed from the other four bents.


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## CapeCodSteam (Jan 2, 2008)

And the winner is... CCSII. Doug suggested I leave it there, as my mark. I'm all set with that idea, thanks. Now they all five match.


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## CapeCodSteam (Jan 2, 2008)

Now that the cold snap has broken we were able to get back outside and do some more work on the trestle. We finished building the trestle yesterday, Doug dug out the holes for the foundation bricks and we measured everything out. It works out great.

Today Doug finished the stone work on one side. Next will be the stone work on the other side and secure with mortar.

Hope you enjoy the pictures.


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