Large Scale Central

Sutro Tunnel Model

Hi friends,

Project-wise, I’ve been sort of quiet these last few months, so I’d like to give a bit of an update on what’s been going on.

Last July, Linda and I went to the Great Steam Up in Carson, NV.

While on that trip, Linda and I were able to tour the Sutro Tunnel site. This was my second visit there, and it was great to see and hear more on this fascinating historical place. This tunnel drained the Comstock mines… belatedly, but still to good effect. For more info, see the Friends site, or just Google “Sutro Tunnel.”

Long story short, I felt inspired to design a museum around a model of the tunnel, telling the story of the Comstock from the perspective of the underground, Th concept was well received.

In October, while at the V&T conference, I met met with the Sutro Friends folks. I was asked, Can a small model of just the site be made, for near term needs? And of course, I said Yes.

Since then, I’ve been spending all my free time, vacation, holidays, whatever, on this worthy project.

Here’s a concept shot of the model. This is of the site around the mouth of the tunnel, which the State of NV only recently received control over.

There will be 16 story panels around the model, helping explain the site features. Many of the buildings no longer exist, but quite a few do. We’re trying to use this model to explain everything that was there, in the heyday of the operation.

I hope to engage some techie talent to extend the 16 topics to one’s cell phone, so that more detail emerges when you get near a feature while walking around.

This is a 100% volunteer effort, so I have some freedoms. On the other hand, the historical discussions and their outcomes can get involved, and I’ve needed to adjust the design to suit.

After a lot of research and design time, I’ve been happy to begin lasering some parts this week.

There will be tracks in the model. In 1:1 they are 22" gauge. But since this model is 1:320, they’ll be tough to see.

Anyway, that’s what I’m working on. This thing has taken over, and unfortunately I won’t be finishing my trestle project until this is done.

And yeah, my timing sucks, with the Mik challenge just starting, and I don’t want to distract from that.

But I needed to get the heavy building stuff on this done now, cuz I’m having rotator cuff surgery at the end of this month, after which I’ll only be doing tiny stuff. And since I’m now building the model (and not just researching or designing), I wanted to share that effort with my friends here.



Very fun and ambitious project. Are you using an actual topo map to get the landscape accurate. I have always wanted to see if I could do a small N scale diorama using a real topo map to get a perfect topography. To lazy though to actually attempt it.

Yes, this is based on a digital topo. Unfortunately it was only available in a raster format, so I’m having to “manually” trace all the lines. If you can get yours in a dxf format, perhaps you’ll be able to more easily transfer them to a suitable CNC process.

Or, for N scale, just have a local blueprint / copy shop print the section you want and at your preferred scale. Make a couple copies, so that you can spray-mount them on card stock and have overlapping edges for gluing.

The trick is to find a viable material (available, cuttable, affordable, etc.) in a thickness that matches the map’s elevation divisions, at your preferred scale factor.

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What is the elevation change per level?

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I volunteer at a local museum and I would be very interested in how you set up the connection to a smart phone. We are trying to do something similar, but we don’t have a “techie” either.

Thanks in advance for any assistance you can offer and good luck with this worthwhile project.


So if you write the 16 story panels in Sanskrit can we call you Swami Jennings and you can name it “Comstock Sutro” tunneling into the silver lining!

Each layer is 3/16" and represents 5’.

I found some .038 chip board to represent 1’ steps, which I’ll put in for more important topo areas. Takes forever to trace those, so I’ll probably not bother doing that with the more mundane slopes.

Bob, will do. It’ll take a while to sort that out, but if and when we make progress I’ll sure let you know.

Now that thar is funny!!

Well, I’m an old-school techie from the MS-DOS/Windows 95 era, but I think I have a clue for one way it could be done…

A QR Code can be printed on the display which is a link to an information page on the internet. Observer scans the code and is taken to the web page.

Jon, that sounds perfect. It would mainly be for a walking tour of the facility, where plaques (and maybe a border in the dirt of some kind) would mark a building’s location. A QR code could go on that, and on the corresponding display on the model. And even in a booklet.

This is all just in the ideation phase, but that seems like a really straightforward approach. Thanks!

I agree. Mobile phones are not considered secure if you can get ‘push’ notifications just by walking close to something! [In plain English, a ‘push’ means it comes to you without you asking. A ‘pull’ means you ask for it, or pull it to you.]

I use QR codes all the time at school for different things. The kids love to scan them and see what it is vs them typing in a web address.

In grad school I did a walking tour for a historical section of Bozeman Montana. Made a digital map with pins for each location, then linked the “pins” with details about the site. Basically one page per site, and all hyperlinked together. The city was supposed to install QR codes ( and print paper copies of a map) but I don’t think it ever got that far.

Thanks for your thoughts, Pete and Craig. QR is sounding perfecter and perfecter.

I also like how the same set pf pages can be accessed by anyone for a virtual tour, if they can’t get there.

My second shipment of foam board came in, so I cut the layers for the third section. Unfortunately, I had to go to a different source… seems like there was a run on the foam board market, maybe everyone’s rolling their own Christmas ornaments this year?

But I found this batch that could get here quickly. Unfortunately, it was a hair thinner, and all the most important upper surfaces were lower than the adjacent section by an average of .09".

So, a bit of surgery was needed, namely removing the lowest layer, in anticipation of putting in a new lowest layer plus a “jacking” layer of .09" whatever.

I’m often jealous of Eric M. for his insightful motto, “Well that didn’t work.” :stuck_out_tongue_winking_eye:

On the brighter side, the “1-foot” layers of .04" chipboard are looking nice.

To keep this thread railroad-oriented, the lines that look like an upside-down tree are centerlines for the track. It won’t operate, being too small. But there will be little 3DP tracks there, and tiny strings of dump cars. Eventually.



Thanks. I’m working on a browser-based app that requires the user to enter a 3 digit code that plays an audio description of the item the user is looking at, but I’m a long way from success.

I’ll be sure to take my micrometer to the museum and measure each step of topography to make sure you have exactly the right steps.

That’s a tad bit more extreme than even I would consider Cliff! That’s crazy your thinking about stuff like that on some that people will see 3’ away. :joy:

I’ll go hide back in my corner now…

Definitely a reason they call it museum quality. :sunglasses:

Well Craig, you’ll be disappointed because each 5’ step will be at least 4" off I think. :stuck_out_tongue_winking_eye: :sleepy: :sob:

That and it’ll all be covered with putty, so no steppage available for measuring. And that’s the saving grace in this approach, haha!!

Speaking of micrometers, this morning I took mine to 5 different art / paper supply stores to find large cardstock sheets somewhere near .040" thick. After 2.2 hours, I was finally back home with some. This is for the “tween” steps of 1 foot elevation change. Give or take 3" each, depending on how thick the glue is. :grin:

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Re the non-matching steps, I completed the surgery this morning by putting in a replacement lowest layer, and a .1" version of it as well. This elevated the entire foam core section so that it lines up with its neighbor. Sort of.

Here’s the 3 sections with 10 vertical feet worth (3/8") of between steps, laid roughly into position.

BTW, I would have loved to have this thing CNC’d out of high density foam, but it would have cost thousands. So I’m sticking to the tools that I have. Yes, I thought about 3d printing it in many sections, but decided this would be the most effective route.

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