An Update to the Thunder Mesa Mining Co. Locomotive Roster

Ex-Estrella & Sonora Grande RR #2 and #3 have found full time work on the TMMC. These great running, beautifully detailed Porter locomotives were originally built by the late Verne Niner for his On30 layout.

Way back in May of 2014 I first described an engine roster for the TMMC. Quite a few things have changed since then so it's high time for an update. As shown in the top photo, two slots in the roster have now been filled by locomotives acquired from the sadly defunct Estrella & Sonora Grande RR. These little Porters were a labor of love for my friend, the late Verne Niner, and I am thrilled that they have found their way on to the TMMC. No 3, Rattler, has a Keep-Alive capacitor hidden ingeniously below the cab roof, while #2, Estrella, has an auxiliary 4-wheel tender to add additional electrical pick-up. The result is that both of these short wheel-base steamers are excellent runners. Even over less than perfect dirty track, they very seldom ever stall or cut-out. No. 3 was purchased directly from Verne before his untimely passing, while the 2-spot came to me from a third party who had bought the engine from Verne but is now thinning his collection. In the fictional world of Thunder Mesa, these engines were purchased used from the E&SG to replace original locomotives #2 and #3 that were lost in a tragic derailment while pulling a double-header across Calico Canyon High Bridge. The TMMC shops will probably never get around to painting the new locomotives or changing their E&SG livery since I enjoy thinking of Verne every time I run them on the layout.

As for the rest of the roster, I continue my practice of loosely basing locomotives on Disney park prototypes and naming them for past Disney artists and Imagineers whom I admire. The exception is #7, Bud Hurlbut, which is named for the talented mastermind behind Knott's Calico Mine Ride and so many other memorable attractions. As of this writing, there are eight locomotives operating on the TMMC, with at least two more planned or under construction.

No. 1 ~ Marc F. Davis

Wheel arrangement: 0-4-0
Builder: Thunder Mesa Mining Co.
Entered service: 1878
Notes: This unique vertical boiler, single piston steamer was built from the recovered wreckage of a steam launch and the 2-4-0 El Dorado. Placed into service in 1878 to help complete construction of the railroad. Named for the proprietor of the Western River Expedition Company.

Modeling notes: Scratch-built from spare parts on a Bachmann HO cable car power truck. Analog DC power. No sound. Mostly a static model these days, though I might rebuild it in the future on a better chassis with DCC. Click here for more on the Marc F. Davis.

No. 2 ~ Estrella

Wheel arrangement: 0-4-2 w/auxiliary tender
Builder: H.K. Porter Co.
Entered service: 1905
Notes: Purchased used from the Estrella & Sonora Grand RR as a replacement for the original TMMC #2 lost in a wreck on Calico Canyon High Bridge.

Modeling notes: This is a heavily modified Bachmann model built by Verne Niner. The 4-wheel tender was built atop an On30 passenger car truck and provides much needed additional electrical pick-up. Lots of extra weight has also been added. DCC Equipped with Tsunami sound.

No. 3 ~ Rattler

Wheel arrangement: 0-4-0
Builder: H.K. Porter Co.
Entered service: 1905
Notes: Purchased used from the Estrella & Sonora Grand RR as a replacement for the original TMMC #3 lost in a wreck on Calico Canyon High Bridge.

Modeling notes: Another Bachmann Porter modified by Verne Niner. The 3-spot has a Soundtraxx Keep-Alive Capacitor hidden beneath the cab roof. DCC Equipped with Tsunami sound.

No. 4 ~ Earl Vilmer

Wheel arrangement: 4-4-0
Builder: Freelanced
Entered service: 1880
Notes: General duty locomotive named for the first general manager of the TMMC.

Modeling notes: Bachmann On30 inside frame 4-4-0. Inspired by the Santa Fe & Disneyland Railroad. DCC installed, sound to be added. Earl Vilmer supervised the construction and operation of both the Disneyland and Walt Disney World Railroads.

No. 5 ~ Frank Thomas

Wheel arrangement: 0-4-2
Builder: H.K. Porter Co.
Entered service: 1881
Notes: General duty mining locomotive.

Modeling notes: Bachmann On30 0-4-2. Inspired by Big Thunder Mountain Railroad. DCC and Tsunami sound on board. Frank Thomas was a legendary Disney animator, one of the Nine Old Men and best friends with Ollie Johnston.

No. 6 ~ Ollie Johnston

Wheel arrangement: 0-4-2
Builder: H.K. Porter Co.
Entered service: 1881
Notes: General duty mining locomotive.

Modeling notes: Bachmann On30 0-4-2. Inspired by Big Thunder Mountain Railroad. DCC and Tsunami sound on board. Ollie Johnston was a legendary Disney animator, train enthusiast, one of the Nine Old Men and best friends with Frank Thomas.

No. 7 ~ Bud Hurlbut

Wheel arrangement: 0-4-0
Builder: H.K. Porter Co.
Entered service: 1883
Notes: General duty mining locomotive named for the discoverer of the Calico Mine.

Modeling notes: Bachmann On30 0-4-0. Inspired by Knott's Calico Mine Train. DCC and Tsunami sound on board. Bud Hurlbut was a pioneering theme park designer best remembered for creating the Timber Mountain Log Ride and Calico Mine Train attractions at Knott's Berry Farm.

No. 9 ~ Admiral Fowler

Wheel arrangement: 0-4-2
Builder: H.K. Porter Co.
Entered service: 1885
Notes: General duty mining locomotive.

Modeling notes: Bachmann On30 0-4-2. DCC and Tsunami sound on board. This Porter is named in honor of Admiral Joe Fowler, The man Walt Disney put in charge of Disneyland's construction, and who stayed on as general manager of the park for its first decade. More on this locomotive here.

Where's No. 8?

Good question! Currently, #8 is still in the planning stages and will either be another 4-4-0 or a tiny 2-4-0 or 2-4-2. The only thing I'm certain of is that it will be named for Ward Kimball, Disney's mad genius animator and unparalleled train enthusiast. It's worth noting that the "Ward" might be the only TMMC locomotive that also has a namesake in the parks, engine #5 at Disneyland. My version will be different, but one simply can't do a tribute to Disney railroading without Ward Kimball. (I hear you Disney train nerds out there! Don't worry, Roger Broggie will get his due too.)

Walt Disney and Ward Kimball with Santa Fe & Disneyland Railroad engines #1 and #2.

There will also likely be an engine #10. It will probably be named in honor of pioneering Disney Imagineer, Claude Coats. In the mythology of Thunder Mesa, Coats is the intrepid explorer who first discovered Rainbow Caverns. In real life, he was the amazing artist who figured out how to do the incredible blacklight water effects on Rainbow Caverns at Disneyland. The famous quote from Walt where he says, "It's kind of fun to do the impossible," comes from a meeting with Claude Coats in the early days of Imagineering. They were trying to tell their boss that the colorful water effects he wanted for the caverns couldn't be done. Coats did the impossible and made it happen.

Ok, friends, I think that should about wrap it up for this time. I haven't updated the blog here as often as I would have liked too in the past few months since life and work keep getting in the way of my train time. A great big "thank you" to those who continue to follow along. More frequent, regular updates can often be found on the Thunder Mesa Facebook Page. Thanks for checking in, amigos. Adios for now!

Video Log: Revised Track Plan with Changes at Calico and Thunder Mesa

Here's Thunder Mesa's revised track plan showing all the changes that have been made. The town of Calico now plays an important role as one end of the railroad in operations. The addition of a reverse loop and short passing siding there now make it possible to operate the layout in a point-to-point fashion. The former village of San Lorenzo has now been incorporated into Thunder Mesa as the "Old Spanish" section of town. This change freed up the far right corner for a turntable and more accessible engine service area. 

The improved track arrangement at Calico forced my plans for an On18 mini-layout to be shelved (again), but the On18 line does make an appearance as a point-to-point mining tram feeder between Big Thunder Mine and the ore bins at Calico. Lastly, the Lone Rock diorama now finds a permanent home on the layout. It's a non-operating scenic feature, but its position against the backdrop offers great sight-lines when looking across the aisle (now called "Coyote Canyon") from the McKennon Arch area.

April 2016 Video Log

Howdy Folks! So much has been happening out here in Thunder Mesa Country that it's hard to know where to begin. The right of way has been changed, towns have been moved, combined or added, and entire areas have been reimagined. On top of all that, a lot of real progress has been made bringing these changes to life with new scenery work and modeling at Horse Thief Canyon and the town of Thunder Mesa well underway. The best way to get caught up on things is with a new video log. After that, I'll delve more deeply into the details below.

Engine #9, the Admiral Fowler

Featured in the new video log is the TMMC's latest locomotive: #9, the Admiral Fowler. Like several of the other Thunder Mesa locomotives, it's an 0-4-2 Porter from Bachmann. I've dressed it up with a fancy cap stack and some custom decals from Stan Cedarleaf.

The "Niner" rounds the bend at Dinosaur Gap. The gold capped stack was made from some HO parts in my scrap box.

Continuing the Thunder Mesa tradition of naming locomotives after Disney Imagineers, animators and others who played a big role in Disneyland's development, the new Porter is named in honor of Admiral Joe Fowler. This was the man Walt Disney put in charge of Disneyland's construction, and who stayed on as general manager of the park for its first decade.

The Admiral Fowler has an unusual crew. The engineer is none other than local legend Chuckwalla Slim, and the fireman is his trusty dog, Sparky. Both figures were painted by my friend, the late Verne Niner, and the locomotive bears the number 9 in his honor. The TMMC has yet to acquire a  #8.

Cattle Cars

The new track plan calls for some larger stock pens at Thunder Mesa and that means I'll need some livestock cars. The TMMC doesn't own any itself, but it does interchange with the parent Santa Fe, Denver & Carolwood and that line does run some cattle cars. To represent some of that interchange traffic, I've repainted and weathered a couple of old Bachmann cars for now.

Livestock car #59 belongs to the Mescal Lines Ry. Disney Imagineer and well known model railroad author John Olson built his HOn3 Mescal Lines in the early 1980s, and my TMMC owes a very large creative debt to that landmark model railroad. 

Car 201 is lettered for the TMMC's parent road, the Santa Fe, Denver & Carolwood. The SFD&C is roughly based upon the Santa Fe & Disneyland Railroad so it seemed appropriate that their cattle cars should bear the same numbering as the original Retlaw 2 cars at Disneyland.

Out with the On18 "mini-layout" and in With a Reverse Loop at Calico

The plans for Calico have probably changed more than anything else on the layout. Earlier this year I decided to nix the idea for a mini On18 Calico layout in favor of a reverse loop and a mainline stop at the town of Calico itself. I concluded that the space could be much better used for a second town to act as the far end of the line from Thunder Mesa. This decision also meant that the steep grade up to Big Thunder Mine would have to go, and that the village of San Lorenzo could be incorporated into Thunder Mesa town as Verne Niner had once suggested. But don't despair On18 fans! If you take a close look at the plan above, you'll see that the old Big Thunder high-line will now be an On18 mining tram bringing ore to the bins at Calico.

Quick thumbnail sketch for the grade changes at Calico.

Out with the old...

...And in with the new. 

The reverse loop is controlled by an MRC DCC auto reverse module hidden below decks.

San Lorenzo Merges With Thunder Mesa Town

Before his untimely passing late last year, Verne Niner and I discussed several different options for integrating his award winning San Lorenzo diorama into the layout. One thing he had suggested was making San Lorenzo the "Old Spanish" section of town. I immediately liked that idea since it implied a long and rich history for the town. It's something you see a lot in the older towns of the Desert Southwest, where Native American, Spanish, and Anglo cultures all come together and overlap. Still, I was hesitant to alter Verne's beautiful diorama until I came up with the new operating scheme placing Calico at one end of the line and Thunder Mesa at the other. Now there was no reason (or room) for a third town on the layout and I found myself thinking back to our early conversations. The decision made, I carefully disassembled the diorama, cataloging everything in pictures, and managed to save every last detail except for the bead-board foam base. In their new placement, the adobe structures have a somewhat different orientation, but their positions from left to right are the same. Several of the structures also have new foundations at differing heights to better compliment Thunder Mesa's boomtown aesthetic. Adding lighting to the structures was always on my to-do list and this move seemed a logical time to also move forward with that project.

The San Lorenzo structures in their new locations as the Old Spanish section of Thunder Mesa. Disneyphiles may also notice that this arrangement mimics the orientation of Rainbow Ridge to the early California flavored area of Zocalo Park at Disneyland (former location of Mineral Hall and Casa de Fritos). This is no accident and the fountain area here is now called "Zocalo Plaza."

LED lighting has been added to the jail.

The Mercantile has also received LED lighting, along with some new signage and a wooden front porch.

One more thing that remains intact from the original diorama is the Pricom Dreamplayer sound system. The mission bells ring, chickens cluck, horses whinny, and the angry banditos still threaten the pig bathing in the fountain. It's a wonderful scene, and I think fondly of Verne every time I look at it.

New Rockwork, boardwalks and Retaining Walls

With the San Lorenzo structures becoming part of Thunder Mesa, it seemed like a good time to tackle some of the scenery work around town too. The new rockwork that forms a backdrop for the town was built and finished with the same techniques I've been describing in the step-by-step build of Horse Thief Canyon. With the rock and paint work done, I've since moved on to building all of the retaining walls, board sidewalks, and steps through town.

The rockwork behind town was built up with carved layers of extruded polystyrene foam. The layers were then blended together with spackling compound and Sculptamold.

Once the sculpt is complete, the rocks are painted with latex and acrylic paints. Here I'm applying a wash of diluted black to darken the cracks and crevices.

After final paint and with a backdrop in place the scene starts to come together. This new promontory above town is called Castle Rock. Just below that is Injun Joe's Cave, where, as legend has it, lost Spanish gold is still waiting to be discovered.

Here's an overhead view of the new board sidewalks and retaining walls built in town.

And a view from the depot platform. The timber retaining walls help to separate the depot scene from the town beyond.  One by one, each of the paper and cardstock mock-ups in town are being replaced by fully detailed models. It would be much more difficult to plan a scene like this without them. The Marshal's Office will likely be my next structure project.

A quiet night in Thunder Mesa Town. Soon, ground cover, weeds, and other details will be added to further enhance this scene.

Engine Service Area

With the San Lorenzo structures moved to the other side of the tracks, that freed up their former location for an expanded engine service area with much improved access. The centerpiece of this scene will be one of the excellent turntables from Kitwood Hill Models. I'll be building the 9" gallows turntable here, and when completed it will allow the layout to operated in a point-to-point scheme between Thunder Mesa and the reverse loop at Calico.

The new engine service area and an inset of the Kitwood Hills Model turntable. Can't wait to get started on this terrific kit!

Horse Thief Canyon

Meanwhile, progress also continues a-pace at Horse Thief Canyon. I'll continue to update the build of this scenic slot canyon in its own step-by-step series.

Horse Thief Canyon - nearly 75' deep below track level. The mainline will cross here on a classic deck-truss bridge.

Effects Control Panel

Each section of the layout will eventually have its own small panel for controlling lights, sound effects, music, and animation. The first such panel is now complete for the Thunder Mesa section.

This small panel was built into the layout fascia on the Thunder Mesa section. The panel face was created in Photoshop, printed on cardstock and laminated with a matte finish clear acrylic. This was then affixed to 1/8" thick masonite. The functions are controlled by simple SPST on/off switches, and a green LED indicates power. All of the effects on Thunder Mesa run on a 9 volt DC system.

Frontierland Music Loop

Every land at a Disney park has its very own soundtrack, usually a one hour music loop that helps to reinforce the land's theme and further immerse guests in the experience. I've always enjoyed the music played in Frontierland and thought it would be a kick to add it to the railroad. I put together my own extended loop that also includes music from the Big Thunder queue and Big Thunder Ranch (now gone!). The music is provided by an inexpensive MP3 player and piped in through speakers hidden under the layout.

What's Next

The first 3 months of 2016 have been a very busy time on the railroad but with each project completed I see three more that still need doing. Coming soon will be new structures for Thunder Mesa Town, ore bins for the On18 line in Calico, a build of my Kitwood Hill Models 9" gallows turntable (can't wait to get started on that one!), some new scenery and effects for Rainbow Caverns, a backdrop to install, and Horse Thief Canyon to finish. All that and more should keep me busy through the end of the year.

A look ahead at the future through the magic of Photoshop. This is the view standing in Coyote Canyon and looking toward Big Thunder Mine and Rainbow Caverns. Horse Thief Canyon is at left and Dinosaur Gap is on the right. The Indian Pueblos will be right about where the thunder storm is on the backdrop. I've also imagined some black drop curtains down below the fascia to give things a more finished look.

Though work on the layout has been steady, I haven't had the time to update this blog as often as in the past. Going forward, look for more long posts like this one to come out every few weeks or so, and for more frequent posts (sometimes several a day!), head on over to Facebook and follow the Thunder Mesa page there. As always, questions and comments are welcome below. Thanks for checking in, amigos. Adios for now!

Building Horse Thief Canyon: Part I

After a couple month's break, I'm back to work on the railroad, jumping right back into a big scenery project. Ive made some major and minor changes to the overall plan since the beginning of the year and there will be much more on that in a future post. For now I'd like to bring things up to date on the scenery being built around Hanging Rock in what I'm now calling the Horse Thief Canyon section of the TMMC.

The new cliff wall under construction below Hanging Rock. I'm trying something new on these big canyon sections, building the rockwork almost entirely from extruded polystyrene foam insulation board - or EPF for short (that's the pink foam board from your local home center). In the past I've used it mostly as a scenery base and finished with other techniques, but now I've found a way to carve the foam layers themselves into a convincing representation of sandstone. The Kato power pack nestled into the cliff base will provide DC control for an On18 mining tram running between Calico and Big Thunder Mine - much more on that in a future update.

This is a big project, and I'll be spreading it out over several updates. In this first part, I want to concentrate on the cutting and carving techniques used on the pink extruded polystyrene foam board (EPF). This insulation board is lightweight, relatively inexpensive, and has been used by model railroaders for many years as a scenery base. While building some rockwork for Rainbow Caverns, I hit on a new technique (new to me) for carving rock textures into the foam using a sanding bit in a Dremel rotary tool. I was so pleased with the results that I decided to use the same method on the deep canyon sections of the layout too. It's a little labor intensive, but really no more so than my previous method of stacking foam layers and texturing with Sculptamold. I've got a ton of rockwork to do, so whatever method I choose is going to take awhile, but these EPF canyon walls will end up weighing much less than the equivalent amount of plaster or Sculptamold. An important consideration if I should ever have to move the layout.

It's easy to add access hatches with EPF scenery. Here I've created a removable section of cliff below Hanging Rock so I can access the wiring back there when needed. Just push in at the corner and then slide the section out. A similar removable section will also be built into the cliff wall on the other side of the canyon.

Overall view of the Calico and Horse Thief Canyon sections as scenery work begins. All of that space between track level and the bottom of the benchwork will be filled with EPF rockwork.

The basic tools and materials used on the foam rockwork. 

• 1" thick EPF insulation board (purchased in 4' x8' sheets)

• Sanding block - medium to fine grit

• Loctite Power Grab adhesive and caulking gun (the best adhesive for EPF)

• Dremel rotary tool and various sanding bits

• Razor saw

• Hot wire foam cutter

• Various hobby and utility knives

The Slot Canyon

Down below the bridges at Hanging Rock is a deep, serpentine defile known to the locals as Horse Thief Canyon. It's a classic Southwestern "slot" canyon, much narrower than it is wide; the kind often found worming back into the sandstone cliffs of Thunder Mesa country. This particular slot canyon is about 72 scale feet deep but only averages about 12' wide. A perfect hideout for horse thieves and rustlers - as long as it isn't flash flood season.

Slot Canyon near Page, AZ. This is kind of the look I'm after with Horse Thief Canyon.

Here I've made a start on Horse Thief Canyon itself, cutting, carving and shaping the bottom three layers. This bottom section will be brought to a high state of finish before I move on to the next three layers of depth. That way, I won't carve myself into a corner by not being able to reach the depths of the canyon for painting and details.

Each rock layer is cut to shape with a Woodland Scenics hot wire cutter, and then the exposed edges are carved into rocky textures using a variety of sanding bits in a Dremel Tool. The layers are then stacked and glued together using Loctite Power Grab Adhesive (see video below).

One more layer of foam added and some spackling to start blending things together. In my experience, common household spackle works just as well as Woodland Scenics foam putty. In fact, I strongly suspect it's the exact same thing - but at less than half the price. I'll let this dry overnight and then it will get a base coat of tan latex paint.

When complete, the canyon will seem to go on forever since it will be impossible to see the end due to built-in view blocks. At night, the flickering glow of an outlaw camp will be visible just around the bend.

To wrap things up for this installment, here's a step-by-step how-to video on my EPF cutting and carving techniques.


Thanks for tuning in, amigos. Next time up we'll do some painting and finishing of the rockwork in Horse Thief Canyon. Adios for now!

The Story of Hanging Rock: Part II ~ Update and Video Log

The scenery at Hanging Rock might only be half finished but that's not going to stop me from having a little fun with Photoshop! Creating images like this helps me to envision the story behind a scene.

Click here for part I

Ready or not, here comes an end of the month update from Thunder Mesa! I haven't had much time for updates this month but scenery work has been progressing on the Hanging Rock section of the layout, and I'm nearly finished with the structure build for Olson & Furlow's Saloon. Even with several things half done, I wanted to share an update and video log on how things are coming along.

Hanging Rockwork

Rockwork and coloring has been completed in the little canyon nook where Olson & Furlow's will find its home. It still needs ground cover, vegetation and other details but here's a quick rundown on how the scene has come together so far.

The canyon walls and rocky ledges of Hanging Rock were built up with layers of 1" thick polystyrene foam insulation - the pink stuff from your local home center. Here the foam has been painted with my scenery base color to better help envision the final scene. There's also a view of the original paper mock-up of Olson & Furlow's, a structure that has evolved a lot from this plan during construction.

Once I was satisfied with the basic shapes, the foam was skinned with a layer of Sculptamold to further texture and define the rocky canyon walls. Sculptamold is a mixture of plaster and cellulose available from American Art Clay Co. at better stocked hobby and craft stores.

After the Sculptamold dries it's time for a coat of my scenery base color: Glidden "French Mustard" flat interior latex paint.

Then I darken the rocks with a spray of diluted black, letting it flow down into all of the cracks and crevices. 

The final paint job is completed using artists' acrylics. The main colors used are Raw Sienna and Unbleached Titanium, with just a little Burnt Sienna and Burnt Umber here and there for variety. The colors are lightly dry-brushed on right out of the tube, catching the rough texture of the rocks and letting the under-color and darkened shadows show through. The wooden retaining wall is a hydrocal casting from Woodland Scenics.

Olson & Furlow's

The main structure in Hanging Rock is Olson & Furlow's Saloon and Store, an appropriately character filled establishment built as a tribute to two of may favorite model railroad authors of the past. I'll be writing much more about this scratch-built model for an upcoming column in Model Railroad Hobbyist Magazine so I don't want to give away too much here. Suffice to say that I wanted something with a lot of texture, charm and visual appeal to act as a focal point for the scene.

To show a long and storied history, I chose to design the structure with a Victorian wooden upper story built atop an older adobe base. Both the wooden walls and the adobe are modeled with illustration board. The base of the structure is 1/4" thick MDF, carved with a Dremel tool to simulate flagstone.

The colorful vintage signs and posters are a hint at the final super-detailing to come.

The old tarpaper roof on the store section has seen better days. The tarpaper was modeled using strips of 220 grit sandpaper painted flat black. The nail heads are tiny dabs of gray acrylic paint.

There's More on Facebook

I'm so humbled and flattered by those who choose to follow my efforts here on this site and also on social media. Thunder Mesa's Facebook page recently surpassed 500 likes and that's not bad for a quirky little hobby like this. If you like this site I hope you'll also come over and join the conversation on Facebook. There's a lot of new stuff posted there first, mostly about this model railroad, but also interesting stuff about the larger worlds of railroading, model building, themed design and Disney. Thank you.

That's all for this time, amigos. Thanks for checking in. Adios for now!

Putting the Rainbow into Rainbow Caverns

Rainbow Caverns on the TMMC is being modeled as three major show scenes: A bat cave filled with glowing eyes, colorful Rainbow Falls, and a beautiful grotto of color changing crystals. Major work has been completed on the central Rainbow Falls scene and that's the topic of today's post and video log.

Most scenery and effects work is now complete on the upper section of Rainbow Falls, a major scene within Rainbow Caverns, and I'm excited to share the results today in a new post and video log. Tried and true "illusioneering" and stagecraft was used to bring this scene to life with a major element being the "Pepper's Ghost" rainbow effect in front of the falls. Check out this month's video log for a rundown on how the scene was created, and follow along with the photo's below for a more in-depth explanation.

Thunder Mesa Video Log: August 2015

Some representation of Rainbow Caverns has been part of the plan for Thunder Mesa from the very beginning. In fact, it goes back even further, starting with early plans to model Nature's Wonderland, and then on to my HO and On30 Big Thunder & Western layouts. At long last I'm getting around to the real magic at the heart of this model railroad and having a wonderful time playing with miniature versions of some of those classic Disney effects. The Rainbow Falls scene is achieved with a combination of ultra-violet light effects and the classic Pepper's Ghost illusion.

A Pepper's Ghost Rainbow

The waterfall is made from clear acrylic, painted on the back with transparent blue UV reactive paint. The "floating" rainbow is a Pepper's Ghost illusion - basically, a view-point controlled glass reflection.

The Pepper's Ghost illusion is used to make semi-translucent objects appear to float in mid-air. In reality, it's the exact same effect you see when you look at your own reflection in a window. Here, however, the viewing angle is tightly controlled so that only the illuminated object, in this case a photo of a rainbow, can be seen in the reflection. If you've ever experienced the Haunted Mansion at a Disney park then you have seen expert use of this classic illusion. 

Here, a simple black box has been created from cardstock with a blurry rainbow printed against black glued inside. An improvement on this design would be to curve the image around the inside of the box so that no edges will be reflected. My second version (not pictured) does just that.

To illuminate the rainbow, a single white 3mm LED was installed in this faux rock fixture.

The next step in creating the illusion is to position a piece of glass at an angle to reflect the picture or object but not the viewer. Note the the glass should be the full height of the scene. In this case, that's five inches.

Rockwork

All of the rockwork inside the caverns is made from pink polystyrene foam. Some are like set pieces, and are removable for maintenance. Layers of these set pieces are positioned to hide lighting rigs, and to complete the illusion of depth in the caverns when viewed from the proper angles. This is Stair Case Falls under UV light.

Here a piece of polystyrene foam is being shaped with a cone sanding bit in a Dremel tool. This goes fast but you have to be careful not to sand away too much!

Each piece is then painted flat black. Once that dries, varies purples and blues are dry-brushed on for a mottled appearance. Keeping the rocks a dark blueish gray helps to make the UV painted objects pop and makes the caverns seem darker, larger, and more mysterious than they are.

The Waterfall

The waterfall was created in the same basic way as the waterfalls for Big Thunder Creek, by sculpting 1mm thick clear acrylic sheet with a hot soldering iron.

The acrylic waterfall was then painted on the back with blue transparent UV paint before being cemented in place on its own set piece with clear silicone caulk.

A single 5mm UV LED is hidden behind the falls for illumination.

UV Lighting

Several of these 5mm Ultra Violet LEDs were positioned strategically in the scene for added illumination. Outside the waterfall, the creek itself is nothing but acrylic UV paint and gloss medium. Here you cam also see the 12v wiring buss that runs below the caverns from a DC transformer. The red wire is positive and the black is negative - important to know when working with LEDs.

I needed a simple way to mount LEDs to the roof of the scene and still have them be flexible enough to aim the lights. Cheep plastic bendy straws came to the rescue. Painted flat black and attached to the ceiling with a dab of hot glue, they make for quite serviceable miniature lighting rigs. A scrim of rockwork hides rigs like this from view.

What's Next?

Down below Rainbow Falls where the track crosses the creek on a stone bridge, there will be a series of deep pools, each slowly changing color as the magical waters drip down from above. Beyond the falls will be a Crystal Grotto, dancing with light. And let's not forget the Bat Cave with its hundreds of shining eyes. Yes, there's much more to come in Rainbow Caverns! But that will have to do it for this time. Thanks for checking in, Amigos. Adios for now!