# Prefab benchwork for the DC&M



## dawgnabbit (Jan 2, 2008)

Hello, All. I suppose this is the right place to post this.

Lately I've been experimenting with prefabricated plywood roadbed modules and leg sets for the Outdoor Division of the DC&M. So far, things seem to be working out well. Here's my son-in-law George holding a freshly assembled curved ladder module. 













This module is 28 ft radius at centerline and 16 inches wide, suitable for a single track. It's made from ACX plywood, painted for weather resistance. It's eight feet long and 8 inches high. Here's what a bunch of them look like installed on the right-of-way:













To set up for curved modules, we marked a circular curve of the desired radius (less half the width) on my cutting table with steel tape and pencil. Simple shop-made right-angle brackets get screwed down next, just touching the line. That (and a few C-clamps) is all there is to the fixture. 












We clamp the inner ladder rail to the fixture, screw radial joists to it, then screw the outer ladder rail onto the joists. The inner rail has to be a bit shorter than the outer rail, of course, so the ends come out even. Also, it helps to pre-paint at least the inner surfaces before assembly. Don't ask me how I know that.
To install a module, one end is butted up against the existing bench work and secured with screws; the free end is attached to a simple leg truss which we also mass-produce in my shop: two legs, a footer, and a couple of sway braces. Legs and footer are treated 2x4's, braces are painted 1x2's.












The footer is set just below surface level on undisturbed native soil. I take pains to make sure the bottom of the recess is nearly level to begin with, then add a THIN layer of crusher fines, well packed, to even out any variations and make sure the footer is supported along its entire length. The footer is buried with more crusher fines, also compacted. Very sturdy and mower-strike resistant.











Any excess leg length is trimmed off, and the job is done. Working alone, I can install a module in just under one hour. It takes that long because I'm VERY picky about grade and cross-level. With two people working, it goes much, much faster.

Why do it this way? Well, the construction season here in Montana is pretty short, and this way I can prefab modules and leg trusses in the shop when it's wintry, and install them when spring arrives. Also, a near-surface footer should be less susceptible to frost heave than a post not set below frost line (which is nearly five-feet deep here). I'm grateful to Paul Johnson of the OVGRS for that info; if it works in Ottowa, it should work in Montana.

Modules can be any width, and any curvature. Here is a look at a completed straight section, showing the lap sidings at Nullarbor, the mid-point of the DC&M. This benchwork came through its first winter with no trouble at all.










Thanks for looking. As always, I'm open to suggestions and comments (preferably favorable).

Steve Seitel


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## Therios (Sep 28, 2008)

Can't get much more solid than that! You also have plenty of width for scenery or more tracks. Can't wait to see it progress.


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## up9018 (Jan 4, 2008)

Nice Steve, I really like that construction method. Something to keep in mind as it makes the layout movable (if needed) 

Chris


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## SteveC (Jan 2, 2008)

Steve

That's a sharp way of maximizing your effort in a short construction cycle, nice job.


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## wchasr (Jan 2, 2008)

Steve! Very nice work! When your done can you come to Western New York with the jigs and spend a few weeks building? just kidding. Nice work and nice results! 

Chas


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## Trains (Jan 2, 2008)

Steve,

Very nice work! Looks like you are off to a great start.
Like to see more pictures of the layout,and a track plan if you have it.

Don


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## NTCGRR (Jan 2, 2008)

i love it, I'd give almost anything to have a big RR., big curves, etc.


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## xo18thfa (Jan 2, 2008)

Looks perfect. Can we come over and play?


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## dawgnabbit (Jan 2, 2008)

Sure Bob, come on up. 

Don - I published a projected route plan long ago, when it was all just a dream. Thing have changed significantly since then, so I suppose I should get a new one together. When I do, I'll post it. 

Chris - I hadn't considered the portability idea. You've got me thinking I'd like to try building entire modules, not just the ladder structure, in my shop, and taking them out to install. Or rearrange, if the mood strikes. Thanks for the idea. 

All - thanks for the kind words, guys. Glad you like it. 

Steve Seitel


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## Chris Scott (Jan 2, 2008)

Steve:
Wow what a great alternative to my layout building plan. I'll definitely be prefabing now. You have a really BIG beautiful layout !!! I'm envious. 

Few qestions;
The ACX you used is how thick? 
Did you build the prefab sections with screws for the stringers ? I'm thinking of screws for the end stringers and nail (gun) the rest of the stringers.

Did you use any special paint or sealer ?

How did you construct the deck with gravel on top ? I'm familiar with using a base of wire screeen, landscaping cloth then gravel on top. 

From your last photo it appears you put a cap the top edge of the prefab walls, I assume to protect it from weather. What did you use for edging ? 
Thanks,
Chris Scott


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