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!

A Quick Look Inside Rainbow Caverns

Once again, I'm back to work on Rainbow Caverns, bringing the "dark ride" portion of the TMMC to life. I'm currently up to my elbows in wiring, LEDs, and black light paint but plan on publishing a full step-by-step and how-to post in about another week. In the meantime, please enjoy this short video highlighting some of the effects in completed scenes thus far. Adios for now!

*Note: Original Disney soundtrack has been replaced by royalty free music from YouTube.

Expansion Update: San Lorenzo Arrives in Thunder Mesa!

Verne Niner's Gazette Award winning San Lorenzo diorama has arrived at its new home in Thunder Mesa Country! The 18"x30" scene fits snugly into a new corner of the layout and will represent one end of the line in operations.

Back in October of last year, my friend Verne Niner announced that he would be dismantling his legendary Estrella & Sonora Grande layout in order to move on to new projects. When he began to sell off the structures and equipment, I was lucky enough to call dibs on his wonderful San Lorenzo Village diorama. After months of planning, and a couple furious weeks of benchwork construction, I'm happy to report that the sleepy border town of San Lorenzo has been safely settled into its new home. The village now resides in a corner of the layout room on its own custom-built layout section. Physically, it's just down the aisle from Thunder Mesa town, but in operations, it will represent the far end of the railroad.

Here's an overhead view of the new 48"x66" San Lorenzo section. This piece of benchwork acts as a literal bridge between the central Thunder Mesa section and the Hanging Rock and Calico sections along the wall. Changes always happen during construction and I've altered the plan somewhat by changing the orientation of San Lorenzo. Now the track enters the village from the opposite direction via a wye, a much more logical arrangement if this is meant to represent the "far end of the line." This change also allows for the San Lorenzo track to connect to a narrow staging shelf that will be built along the wall. What I'll lose in aisle width should be more than made up for in enhanced operations.

This section of benchwork will also house a large chunk of Rainbow Caverns. The foreground track will curve through three cavern scenes before emerging at Hanging Rock.

Here the existing layout joins the new benchwork and the new route through Rainbow Caverns. Passing trains will be viewed through rugged cave openings and the largest scene will feature some dramatic subterranean waterfalls.

I use what I call the "box and stilts" method for building benchwork. Basically, that consists of a box-girder frame made from 1"x4" lumber and 1/2" plywood subroadbed atop 1"x3" risers or "stilts." Here, the subroadbed top has been cut out and positioned but risers have yet to be added. I find this to be a simple, flexible, and somewhat economical method that has served my needs well on a number of projects.  

I cut the 1/2" plywood to size and then layout the track centerlines with a straightedge, bar compass, and actual track components like turnouts. Then, allowing at least1.5 to 2 inches on either side of the track centerline, I cut everything out with a jigsaw.

Here's the San Lorenzo depot area before cork roadbed and track were laid. The airspace between the roadbed and the box-frame makes it easier to add scenery below track level. Everything is held together with drywall screws.

That should bring everything up to date for this week. Now I'm just waiting for some more Peco On30 track components to arrive so I can finish up this section and get everything wired. As always, questions or comments are welcome below. Thanks for checking in, amigos, Adios for now!

All those shots of bare plywood benchwork can get a little tedious so here's some eye-candy. In addition to San Lorenzo Village, the TMMC also acquired E&SG Porter #3, the Rattler, along with Lytum & Hyde Explosives Co. boxcar #66 (I designed the decals and Verne Niner painted and detailed the Bachmann car). With its handsome red livery, the TMMC shop crews may never get around to repainting the three spot.

Jumping into Rainbow Caverns

"Now we're going deep into the earth to view the dazzlin' Rainbow Caverns! You'll see giant stalagmites, stalactites 'n colorful falls on every side..." 

- Recorded narration from Disneyland's Mine Train Thru Nature's Wonderland.

Let's Go Spelunking!

After a couple months away from working on the TMMC I figured it was high time to jump back in with both feet and get started on a major project again. Some version of Rainbow Caverns has been integral to the idea of Thunder Mesa ever since I first happened on the idea of freelancing a Disney-esque railroad. Until recently the Caverns have been an empty foam box that trains travel through, but now I aim to remedy that with scenery, animation, sound and lighting effects; creating a colorful underground world seldom seen on a model railroad. I won't try to recreate the Disneyland version scene by scene. Instead I'm going for something more like an homage that captures the feel of the original, along with a little of Knott's Calico Mine Train salted in for good measure.

Geyser Grotto in Rainbow Caverns on the Mine Train Thru Nature's Wonderland, Disneyland USA. © Disney

Cavern scene on the Calico Mine Train, Knott's Berry Farm, USA.

Planning the Caverns 

Rainbow Caverns will be constructed as two separate scenes, each one executed like a small diorama. The first scene will be on the original section of layout almost directly beneath the town of Thunder Mesa. A second, larger scene will be built beneath the Calico Section once track has been laid through that part of the expansion. Since the track and most of the infrastructure is already in place for the first scene, I'll be starting there.

The area for Scene 1 currently has the exterior scenery roughed in with pink foam and the interior painted flat black. The scene will be viewed through cave like openings in the cliff wall and a large hunk of this wall can be removed for access.

Scene 1 of Rainbow Caverns will be viewed through these cave openings in the cliff face.

Here a removable section of scenery has been placed to one side to enable work on the interior of the caverns.

A Backdrop for the Diorama

Scene 1 will be a classic "wet cave" with rushing waterfalls and a large chamber filled with stalagmites and stalactites. In addition to lighting and sound effects, one of the most important elements for making this shadow-box like diorama work will be a convincing backdrop. Since I'll literally be working "inside the box" in rather close quarters, it just makes sense to paint and install this internal backdrop before any more work is done.

I created my Rainbow Caverns backdrop on a 5" x 15" piece of  Strathmore illustration board. Working from the darkest shades to the lightest, I painted the cavern scene with artist's acrylics, using photos from Disneyland, Knott's and real world caverns for reference.

The completed Rainbow Caverns backdrop ready to be installed on its shadow-box diorama. The colors are intentionally over the top, nearly florescent, in order to show up well in the dim cave. They don't call 'em Rainbow Caverns for nothing!

And here is the scene with the backdrop in place. It's a little difficult to photograph without any lighting installed yet so I composited a couple of pictures in Photoshop to illustrate how it looks in person. The next step will be constructing some 3-D cavern scenery to blend with the backdrop. Just in front of the locomotive in this shot will be a ceiling to floor waterfall, animated by fiber optics lights.

Several LEDs will be used to light the interior of the Caverns, including some ultraviolet lights. A hidden speaker will provide the sounds of running and splashing water.

On Down the Line

With the all important backdrop painted I can proceed with building the rest of the scene. Next will come some unusual subterranean rock formations carved from polystyrene foam and painted to blend with the backdrop. Then I'll try and tackle an animated waterfall with twinkling fiber optics. Should be fun!

Thanks for checking in. Adios for now!

The World of Thunder Mesa

Click for a much larger view.

Today we have an illustration of Thunder Mesa Country, the imaginary world of canyons, western towns and scenic wonders served by the TMMC. This is a spread-out and expanded view of just about everything that does or will exist on the layout as it might be seen from a low flying plane. One thing not on the layout is the junction with the Santa Fe, Denver & Carolwood, seen on the far right side of the drawing. Only a short section of track represents this interchange on the model.

I created the drawing to help visualize both the scenic treatment of the expanding layout, and the operation of the railroad between Thunder Mesa and Calico. This is what I see when I look at the layout and what I imagine as each new section is completed. To really see where the layout is headed, compare this drawing to the updated track plan posted last week.

Adios for now!

Multi-Project Update

A train snakes its way through Dinosaur Gap on a moonlit night.

My good intentions for posting a new weekly update every Monday were thwarted last week by a total hard-drive melt down. The good news is that all my data was saved and things are now back to normal. Meanwhile, it's been a busy couple of weeks in Thunder Mesa country with many projects moving along toward completion. Expansion progress continues, Rainbow Caverns are beginning to take shape, a new turntable has appeared in Thunder Mesa, the town itself has relocated and expanded, and work has begun on a small depot.

Expansion Progress

Track has been laid on the new layout sections and I'm finally able to run trains again! Much work is still needed on the Calico corner section but the main loop around and through Thunder Mesa is now complete.

Testing a train on the new loop section. Everything works! I'm using Peco On30 flex-track and turnouts throughout the layout. It doesn't have the finer scale appearance of Micro Engineering track, but it operates flawlessly.

The hidden wye within Rainbow Caverns. The unfinished foreground track will go to the new Calico section and "points beyond." I lay my track on Midwest HO scale cork roadbed using contact cement and rail spikes here and there as needed.

No track yet on the Calico section. I'm having second thoughts about the track arrangement here and how it will lead into the next section. Plans are still up in the air and I might change the route before laying down the track.

Rainbow Caverns

With the new loop completed I was able to rough in the area that will become Rainbow Caverns. The caverns will be filled with cool lighting and artificial water affects and should become a real focal point of the layout. The trickiest part so far has been planning for and hiding the necessary access to reach trains and track when the need arises.

The canyon wall on the backside of Thunder Mesa roughed in with 1" Polystyrene foam. The cave-like openings will be viewing windows into Rainbow Caverns. The pink foam is carved to shape with a hot wire cutter.

Closer look at the cave opening. Not much to see here yet. The interior has been painted flat black. 

A large piece of the cliff-face is removable to provide access to the Caverns. The removable section is at left. Most of the town now also sits atop a removable foam access hatch.

The Caverns will are being built as a series of shadow-box like vignettes that the trains will pass through. The first two scenes will be reminiscent of great limestone caverns like Carlsbad or Mammoth Cave, and the third will be a major underground mining scene like the famous "Glory Hole" on Knott's Calico Mine Ride. The mine scene will tie into the On18 Calico Gold Mine Diorama to be built above the new Calico section.

A Turntable for Thunder Mesa

The new track plan calls for a 36' turntable at Thunder Mesa. This will be vital to operations as it not only provides a way to turn trains, but also acts as a switch, enabling the locomotive to run around its train. I first saw this type of track arrangement on John Allen's HOn3 Devil's Gulch and Hellengone and always though it a perfect solution for a narrow gauge railroad built in a tight space.

36' turntable at Thunder Mesa. Note the timber cribbing retaining wall around the back of the TT.

I started with a Walther's 120' N scale manual turntable. Sorry to say I cannot really recommend this kit. The castings are very rough and covered with flash and the instructions are a joke. I used it because the pit is the right size and I had it lying around from my old N scale days. 

Once the pit is painted and weathered it doesn't look too bad. I painted it with Krylon flat Grey Primer and a light overspray of Krylon light tan for a nice concrete color. The pit rails was painted with rust colored acrylics and the weathering is done with colored chalks. I drew "cracks" into the concrete with a hard lead pencil and then punched them up here and there with a fine point Sharpie. 

I built an On30 bridge on top of the N scale girders using scale 6"x8"x8' ties stained with a combination of Minwax Dark Walnut and Early American. I use the Minwax touch-up stain pens to stain most of my wood. 

I laid out the rails using a length of Peco On30 flex-track - keeping a few ties on at each end helps to keep thing in gauge. The rail was then spiked down with medium rail spikes from Micro Mark; a good match for the cast in spike detail on Peco track. The rails were painted using Floquil paint markers Rail Brown and Rust. Feeder wires were also soldered to the underside of each rail at this time. The wires extend through the center of the bridge and will connect to a DCC auto reversing unite below the layout.

The rails were trimmed to length and aligned with the approach track on the layout before final spiking. Scale 6"x6" guard timbers were added along the ends of ties along with 1"x12" catwalks on each side. Grandt Line nut, bolt, washer castings finish the bridge.

Finally, the turntable was leveled and shimmed to meet up perfectly with the approach track. Just waiting on delivery of an MRC auto-reversing unit to complete the wiring. The turntable is not motored but I'm engineering a simple gear assembly to manually turn it from the layout fascia.

Moving the Town

Once I started roughing in the scenery around the turntable area it became apparent that there would be much more room for the little mining town than there had been when it was squeezed in behind and above the Big Thunder Mill. The original plan for this area called for a mine of some kind, but that will now be located more logically closer to the mill, while the town will be more fully fleshed out and expanded in the area above the tunnel.

The little mining town of Thunder Mesa. Most of the buildings here are temporary paper-models based on the original Rainbow Ridge structures at Big Thunder Mountain in Disneyland. These quick and easy mock-ups are very helpful when layout out a scene like this. The amphitheater looking area behind the turntable will be detailed with rock-work and timber-cribbing retaining walls. This was a neat detail on Malcolm Furlow's HOn3 Denver & Rio Chama Western that I always really liked and wanted to emulate. To the left of the turntable will be a steep, switchbacking road up to the mesa top.

Thunder Mesa Depot

Since, in my world, the Big Thunder Mill is used to process ore rather than load tourists as it does at Disneyland, I knew that some kind of small depot would be needed for the scenic excursion trains. This depot will be the first actual structure built for the layout (other than bridges) and should make for an interesting and detailed foreground scene. The depot building itself will be tiny, with a footprint of just 10'x16' - really not much more than a ticket office and small covered waiting area. The platform will be bigger however, about 50' long by 20' at its widest. Here's how I built the platform:

The first step was to create some new real estate for the depot along the layout's front edge. This 24"x7" bump-out is the same width as the existing "coffee-shelf" and so adds nothing to the overall footprint of the layout. Some stock pens are also planned for next to the depot.

I want a strong a durable base for my structure so I'm using 1/4" MDF. Here is is cut to the basic shape of the platform. 

The 1/4" thickness of the MDF is perfect for simulating the look of scale 12"x12" timbers. I dragged the blade of a razor saw along the edges to simulate woodgrain and used a utility knife to carve lines, simulating the ends of 12' long timbers. 

Once stained with Minwax Dark Walnut and Early American, the MDF is very difficult to tell from dimensional strip-wood. 

Laying out lines every 1/4" for the scale 1"x12" decking. This will help keep things straight. 

The decking in place. The white square is a piece of illustration board glued to the MDF for the ticket office footprint. The actual floor will be built on top of this. 

I used a hard 5H pencil to press nail holes into the decking. 

Weathering done with colored chalks. This would be harder to do once the structure is attached. 

Checking the fit on the layout.

Here's a preview of the depot itself. I laid out the basic shape and built a card-stock mock-up to test clearances etc. This will act as my plan for building the actual structure.

Okay! That's about it for this week. Be sure to check back next Monday for the next update on these and many other projects. (God willing and the computer don't crash!)

Thanks for checking in!