# Bents for a Pile Trestle - a tutorial in doing it different



## Russell Miller (Jan 3, 2008)

Ok, so there was an area in my layout that I never completed. I decided that now is the time to get it done so that I can be open for the West Coast Regional Meet that BAGRS is hosting in July. I wanted to make something that I haven't seen in all of the 100's of layouts that I've visited over the past 10 years. I've already scratch built a redwood timber frame trestle so now I needed something different... I wanted to make a Piling Trestle with round uprights that could stand in a shallow pond without rotting. My plan is to make a watertight pond area that will remain dry most of the time but I will fill the area with water when I'm hosting an open house tour. The idea is that it will be "still" water to allow the reflection of the train to be photographed as it passes.
Here is the area to be changed. As you can see, the supporting PVC is completely visible.









The first thing I did was to mark and record the track height above the retaining wall using a water level before cutting and removing the support structure. My son and I measured the height at every 8" since that will be the distance between the bents.










Now comes the tricky part; what to use and how to make the round bents. I decided early on that I wanted to use some Epoxy Fiberglass Tubing that is available from TAP Plastics. I used the .505" OD for the main bents and the .414" OD for the internal supports. For the sway bracing that crosses across the bents, I was able to obtain some 1/8" thick black G-10, another very stable fiberglass based material. I cut these materials to size using a wet saw used for tile cutting that I obtained from Harbor Freight.

Here are all of the pieces used. I cut the top cap piece from some recycled redwood that my wife picked up for me so that I could build her a chicken coop; but that's another story... I tried to use some plastic put that proved to be to fragile after drilling.










I drew up full scale plans using information that I gathered from Model Railroader's book "Bridges & Trestles" and from the January 2005 issue of _Railroad Model Craftsman._ 

The first step was drilling the top cap piece at the angles I need for the bents with the correct size drill bit. Finding a .414" drill bit prved to be impossible so I ended up using a 27/32 drill. As you can see, I didn't get the holes too straight in this cap...











I glued the 1.5" long support pieces into the wood using E-6000. Don't worry about any excess glue, that will come off in a later step.









The actual bents are a tight fit over the support pieces. I had sanded the tops of the tubes to closely match the angle where they meet the wood. 











Now the recently glued together bent is place in the spacing jig and the first hole is drilled. I drill the upper hole in the wood first and insert a 2-56 nut to hold the sway brace in place while I drill the other holes. The next hold to be drilled is on the far left bent.










Here the remaining holes have been drilled, each time a 3/4" long 2-56 bold was dropped in the hole to make sure nothing moves. Note that the center hole is NOT drilled through the far side. That side will be drilled as we work on the second sway brace.










Before I can flip the bent over to work on the other side, I first must cut off the sway brace using a cutoff wheel in my Dremel. Note that all of the nuts are now bolted tight to keep everything from moving too much.










Now we can flip over the bent and do the same thing to the other side. 










Here is a photo of the nearly completed bent. It is quite strong and will be cut to length as I install it on the railroad. The original plan was to make everything from black material but that didn't work out. The plan now is to prime and paint everything black to simulate creosote soaked timber.










The trick to using E-600 is to resist the urge to remove the excess while it is still wet. If you try that you just end up smearing it all over the place. Just let the glue dry for a minimum of an hour but not more than 24 hours and you can just grab a hold of the excess glue and peel it off. It is amazing how clean it comes off.










Each bent takes me about 20 minutes to completely assemble using the precut pieces. I only have a couple of dozen more to go!. Hopefully I will be able to get these done and installed in the railroad before the July meet...

Russ Miller


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## Robert (Jan 2, 2008)

Looks great Russ. What is the purpose of the connector pieces rather than gluing the bents directly into the cap? I'm assuming additional stiffness but you give that up at the bottom? Look forward to seeing some of it with a coat of paint. Thank you for the post. 
Robert


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## Russell Miller (Jan 3, 2008)

Posted By Robert on 12 May 2011 01:13 PM 
Looks great Russ. What is the purpose of the connector pieces rather than gluing the bents directly into the cap? I'm assuming additional stiffness but you give that up at the bottom? Look forward to seeing some of it with a coat of paint. Thank you for the post. 
Robert 
Robert, thanks, a lot of planning went into the design.
The wood cap piece is the same width as the diameter of the round posts. I can't drill the cap at the post diameter of .505" as the sides of the cap will just give way. Drilling the hole for the smaller support pieces gives me plenty of wood on each side. The connector pieces also add a lot of strength which is important because the shorter bents will not have sway bracing. I've made a bent without the sway bracing and it is quite strong with just the glue holding the support pieces in place. I can't glue or vertically pin the posts to the cap, like I did on my square timber trestle, because the round posts are actually tubes and they are hollow so there is nothing to nail to and no surface to glue to the top cap.

Russ


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## fred j (Jan 12, 2011)

Great Pictures and ideals for building them, Thanks for posting.

Fred


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## John J (Dec 29, 2007)

When you travel between Wickenburg AZ and Parker AZ you follow the California and Arizona RR. There is a miltitude of different treselts that cross different size washes. 
A lot are of the concrete piller design look much like what Russ had done here. I think it looks great and is a good idea.


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## Greg Elmassian (Jan 3, 2008)

Very interesting and well thought out construction. 

I like the choice of materials, should be very low maintenance, maybe some sealant on the wood once every 5 years? 

Greg


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## Russell Miller (Jan 3, 2008)

So I got the pond all fiberglassed up and the first row of bents in place right before some heavy rains hit on June 30th. It's not supposed to rain in California at the end of June...
Anyway, at least the pond holds water!


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## Nutz-n-Bolts (Aug 12, 2010)

Very nice. That has a great feel to it. The trestle looks right at home there. I think water features add a tremendous amount to a layout. You can always count on mother nature to put your work to the test!







Looks like you passed with flying colors.


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## Torby (Jan 2, 2008)

That's really cool!


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## up9018 (Jan 4, 2008)

Excellent Idea....I have been trying to think of a way to make long lasting bents for my mill pond, what a great idea. 

Thanks, 
Chris


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## SE18 (Feb 21, 2008)

Russell, 

OK, now I see the use. Brilliant. I'll share link with some friends. 

Dave


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## gnichols (Jan 9, 2008)

Nice idea. Thinking one possible step further, why not use all plastic and make them look like they were made totally of steel (except the ties of course)? Gary


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## Russell Miller (Jan 3, 2008)

Well the bents have all been stuck down with Magic Sculpt to the fiberglass pond and painted black. Now all I have to do is finish the abutments for the bridges, lay in the fines for the bottom of the pond and fill it with water.


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## Russell Miller (Jan 3, 2008)

Well, I'm open Wednesday for the West Coast Regional Meet and we're almost done!
Got the bridges in and leveled.









As you can see, the Blue Fines are in hiding the fiberglass and the rocks are mortered in place to hide the edge of the edge.









Now all we have to do is Add Water!


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## Stan Cedarleaf (Jan 2, 2008)

That looks right nice, Russ.









A wonderful way to make a great looking and very functional trestle.


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## benshell (Oct 1, 2008)

Looks great! Very unique and the results look incredible. I wish I were going on the tour tomorrow. I went on Sunday, but this week I have to work. (I already took off too much time to go to the NGRC!)


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## Russell Miller (Jan 3, 2008)

The water is in and the Open House went fantastic! The reflections worked just as they were planned though I wish the bottom of the pond was just a little darker...


















Russ Miller


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## SE18 (Feb 21, 2008)

Nice. Once the algae forms, it will look even better. Maybe get some tadpoles and snails.


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