Modeling a Tunnel | Goldfield & Calico

[Music] Howdy Folks Dave here at Thunder Mesa studio with another project today for the o30 Goldfield and Calico model railroad this is my Mojave Desert themed 1920s era Narrow Gauge layout with just a little bit of notot Berry Farm on the side and today I want to pick up right about where we left off last time after installing this new section of backdrop behind the town of Calico I want to build a tunnel that separates the onstage parts of the layout from the backstage staging yard I want to model it inside and out because a lot of the interior of the tunnel is going to be visible and I'm going to take you with me every step of the way and so the first thing I want to do is paint that area of track with some rum dark brown camo that's because it'll be a lot easier to access it now than it will be after the tunnel is built painting with dark brown camo is a good first step it's a great color for simulating rusty old iron but there's a couple more things I want to do here to make this track look a little bit more realistic and I've got some granite gray here and some territorial Bays from Apple Barrel I'm just going to mix those together a little bit and I've got a stiff brush here and some corrugated cardboard get about 90% of the paint off and we'll just dry brush that onto the ties and that's really going to bring out the cast in wood grain detail here along with the rail spikes and some of these that are out here in the sun I want them to be a little bit more gray a little bit more faded and it's usually very damp inside of tunnels even in the desert so I want to have some Rust indicated on the rails I'm going to use my pan pastels for that that's the best thing I found for doing this this is the dark rust I like to apply that first just hitting the sides of the rail here and the uh top tops of the spikes then I like to come back with the lighter rust color just go over it again hit it in a few spots here and there right now I want to hit it with some clear matte finish now with this dry I want to take some of my odorless mineral spirits and one of my track cleaners and clean the uh the paint and pastels off the top of the Rails like to do this as I go after each step because a lot of Gunk is going to build up on here and I want to make sure the train still run you know dip that in there run that across the uh the rail head till it's shiny again well now with the track painted I'm ready to start on the tunnel itself and I've decided I wanted to be a basically a Rock Tunnel something that was just blasted through solid rock with without a lot of Timber framing on the inside but I do want Timber framing on the opening or or the tunnel portal and for that I've got some ocale 12 by 12s that I'm cutting to length and I've drawn a little template here to help out with construction and make it a little bit easier so I've drawn what is really a very basic uh tunnel portal here that's going to be 16 ft tall and 13 ft wide a couple of diagonal braces and I think to make construction a lot easier I'm going to glue this up on a piece of foam core got a scrap right here so I'll coat the back of this super 77 spray adhesive now I can just cut this out take and put some some clear tape over the top of my lines so that when I'm gluing the pieces up they won't stick to the paper so I want to build two of these frames and each one's going to need uh these two 4 inch long pieces one 3 and 3/4 inch piece and then the the angled corner braces and I think the easiest way to proceed is to measure them out and cut them over on my Banda now if you don't have a band saw don't worry you know you can cut it with a razor saw I just find it get a little bit more accurate Cuts this way I'll take my Razor saw blade and distress all of these pieces a little bit now I can get some stain on all of these pieces with my shoe dye and rubbing alcohol mixture now we'll set all those pieces aside to dry for a few minutes and we'll be ready for some assembly okay now with the stain dry going to use some double stick tape on here right over the other tape I added earlier that should make uh building these pretty quick and easy lay them right on top of the tape line them up with my [Music] lines use some yellow Carpenters glue is that the shorter one yeah that top beam across and a tape will hold it in place by the way I should probably mention I'm not modeling any specific prototype here this is my own design based on you know a lot of different tunnel that I've looked at and researched these these tunnel portals were usually engineered in place you know for the for the specific site it wasn't really much of a standardized design other than you know the height and the width for the for the locomotive and the cars to clear my primary goal here is just to have a a portal that's sufficiently Railroad and interesting looking now I have some side raining wall pieces that I've laser cut these boards would be about 3x 12 another thing I always like to do on the ends of these boards these These are going to show so I'm going take and cut all the way through where the Scribe ends so that from the end they will look like individual boards another technique I discovered kind of by accident when I dribbl some stain across some wood is you take a loaded brush like this and just tap it you see the little dots Landing there little dark spots of stain and those are going to look like uh not holes or stains or imperfections in the wood now I can pop this off of here we can start putting this whole thing together get some glue along this Edge that goes right here like that what I'm trying to show here is sort of some Square set Timber framing which is u a technique that was brought over to the United States by uh Cornish miners used extensively in underground mines and also used in railroad tunnels there would have been a mortise and Tenon joinery on all of these joints in real life but I'm not going to model that part because it doesn't show that would just be crazy make sure we get glue on all of these mating surfaces one thing I know that'll help to keep this square is putting the roof on now go ahead and glue the other side on now I've got this footer piece goes right there in a long diagonal brace frame those boards in and I've got these short upright Pieces Just go right about there then I want to add an additional layer of 12 by 12 bracing just around the opening here so that's going to kind of sandwich those those boards in between the two 12 by 12s I want to position this right about here and we'll run a couple of trains through here to make sure everything clears properly this is the the longest car that I'm going to be running see if it makes that without uh having any clearance issues yeah no problem good so the idea here now is to glue this into place and then I can build up the rest of the tunnel and the scenery around it so now I've begun sculpting some um chunks of 2in thick X PF foam to fit precisely around my tunnel portal and create both the Hillside and the interior of the tunnel let me show you exactly how I'm doing that first I take a couple of quick measurements so I can cut a chunk of foam to the size I need that looks like about two and 3/4 by seven and a quarter and I come over here to my band saw and cut out a blank to those Dimensions next I want to mark it and cut it to match the angle of the backdrop as it relates to the angle of the tunnel portal sounds complicated but it's a little easier than you might think I just need to line this up with the edge of the tunnel portal here and one corner hitting the backdrop then put a straight edge right across there draw a line and that's my angle to cut now I've marked this back a quarter of an inch here so that the tunnel portal will be inset into the Rock now I just need to cut out an allowance for that 12x 12 beam that's on the [Applause] outside and now I've got a piece of foam that should fit perfectly right here now I can outline or Trace that angle right there and remove a lot of this material and I'll probably use the hot wire cutter for that then I can carve and break away a little bit more material with my hobby knife make this look more like rock and add some texture and Strata with my wire brush then on the interior of the tunnel same thing put my wire brush this to look like it was blasted out of solid rocks so I'm going to dig in there here and there a little bit then when I'm happy with the way that looks use my heat gun freeze that texture in place perfect now the next piece is a lot easier because I can just trace the outline of this piece onto another chunk of foam now I can take this off all as one piece use my wire brush here at the joint make sure everything Blends together nicely now I'm working on the top piece and this piece has to do a couple of things one it has to form the the roof of the tunnel but it also needs to provide a transition here into this scenery that's going to be built to the left so as I carve this way with the hot wire cutter I'm doing my best to try to match this slope that I've indicated here on the backdrop so everything Blends together nicely I'm also cutting away a little bit of material here at the roof of the tunnel so I can uh detail that to make it look like rock and now I want to just keep building up the layers okay I'm pretty happy with the way this is looking so far so now it's time to turn my attention to the other half of the tunnel which will be located behind the backdrop [Music] once again use the wire brush and the heat gun then I can use that as a pattern for the next piece okay now for the other side now I've cut a blank for the roof of the tunnel and I'm going to attach it temporarily with some 3inch long drywall screws the idea here is that I'll be able to lift the whole thing off and then I can carve Mark and then carve the roof of the tunnel now I don't really need to detail the roof of the tunnel I mean it's not something a lot of people are going to see but unless they're short you knowless their kids or really want to get up there and look and you know I don't want them to be disappointed with a blank roof right going to carve a little bit of this out and uh make it look like rock like the rest of it now I can put the whole thing together goes there that goes there that goes on top I'm going to glue the lid onto the tunnel but the tunnel itself is not going to be attached uh to the layout deck that way I'll be able to lift the whole thing off and clean and maintain the track if I need to now I want to fill in these little gaps between the layers of foam and I've used a lot of different things to do that over the years I've used sculpt to mold I've used spackle joint compound all of those work well but this time out I'm going to use this Woodland scenix Flex paste I've got a big jar of this left over from when I did the Christmas layout last year and I thought I'd give it a try on here it's basically just vinyl spackling compound with a different name on it so I think it should work pretty well and the reason I haven't glued any of these pieces down yet is because now I can just take them off of here take them over to the workbench and finish them there without uh messing up my tunnel portal so I've got my Flex paste a little bit of water stiff paintbrush couple of pallet knives I'll just go at this stuff dries pretty fast too about uh 40 minutes of course uh they recommend that you put it on in thinner coats You Want to Build It Up in layers put it on about 1116 of an inch thick at a time and then let that dry and uh put on another coat afterwards as it starts to harden I can go back and texture it a little bit more make it blend with the rock better I'm just stippling it with the brush here to give it a little bit of texture this stuff is uh non-toxic and water soluble and you can clean up with the soap and water before it dries once it's dries it's going to be waterproof you be able to paint it of course I want to do the interior of the tunnel also okay I think that's dry enough now that I can get some paint on all of these pieces I'm going to start with my Scenic base color and if you watched my previous video on the backdrop putting in the backdrop for Calico this is the same color I used Bo on that fact I'll be using all the same colors so it Blends in perfectly with the backdrop I just want to get a nice even coat on all of the parts that are going to show the inside and outside of the tunnel well I gave these a couple hours and I think they're sufficiently dry now that I can move on with the next step and that's to go over all of the pieces with a dark wash and this is a Ivory black and burnt umber acrylic paint diluted with a whole bunch of water so that it's it's a transparent wash and I just want it to get back into all of the cracks and crevices darken those up that's going to give us a much more realistic look to the Rock work when all is said and done and when it goes on it's going to look really really super dark but don't worry that's not the uh that's not the final look now to finish up the paint on this rock work I've got just three colors here I've got some unbleached titanium which is a nice very light tan Warm White somewhere in there uh some raw Sienna and some uh burnt Umber and the first thing I want to do is take some of this Scenic base color and this is the stuff I have mixed up by the gallon this is actually latex paint and I'm going to lighten this up a shade with this uh unbleached titanium I've got a sort of a semi stiff brush here a little bit smaller than what I used to paint most of this and I'm going to just go over the surface like this hitting the high spots and if you've seen my previous Rock work videos you this is all going to look very familiar this is pretty much the way I always do it you can see what I'm doing here I'm just just hitting the high spots on the Rock and so the lower darker material is going to show through so it's kind of like dry brushing and this is really going to start to give uh this Rocky slope some definition very glad I decided to do this over at the workbench for one thing it's keeping paint off of my tunnel portal that I built Al a lot easier to see everything turn it in every direction on the deeper part of the tunnel that's going to live back behind the backdrop I really don't need to do too much more than this mostly this is just going to disappear into darkness I'll take some of my raw Sienna put it right in there a slightly darker shade it's darker and redder create some streaks coming down the sides of the rock work I'll just mix in some more of that unbleached titanium for a highlight color go shade lighter again just indicate where sunlight is hitting the rocks and I'm going to do more finish work on all of this over at the scene I just wanted to get it up to a certain level before I install everything now I'm going to start reassembling the tunnel in fact I'm actually going to glue these these side pieces down notice I'm not gluing them to the backdrop however I do want the backdrop to remain removable ni going to glue the top on yet because something I need to do first and the thing I need to do is balast the track and for that I'm going to be using chick grit this is crushed granite not to be confused with chicken grit chick grit is for baby chicks if you get chicken grit it's much much larger this stuff is very small fact it's just the right size for O scale ballast I'm just going to sprinkle it on picked this up at my local Feed Store you don't have a local feed store near you you know Amazon probably carries it just remember chick grit not chicken grit there is a difference and I usually just pour it down the track Center Line put a little bit on the uh the shoulders of the road bed also and then most of the time is spent manicuring it and position ing it with a with a soft paintbrush get it off the tops of the ties as much as I can Bast is supposed to be down between the ties and below the rails now you can see why I didn't want to put the lid on the tunnel just yet and as for the back half of the tunnel I'm not even going to put that on yet until I get this pretty well manicured just the way I want it this is one of those steps that you really want get right the first time you don't want to have to come back and fix it later so I really take my time I'll just sometimes I'll go Tie by tie you know one side of the Rails at a time just to make sure there's nothing up there that's going to interfere with the uh with the passing of the trains so this is how I like my Ballance to look before I glue it down off the the tops of the ties completely and really no higher than the bottoms of the Rails so pretty well manicured actually for a funky old Narrow Gauge line like this one and to glue it all down first thing I want to do is completely saturate the ballast with a little bit of wet water and a spray bottle wet water is just regular water with a drop or two of liquid detergent in it to break the surface tension and then I'm going to use some diluted white glue this is just regular Elmer's Glue diluted 3 to one with water like to dribble it on from an old glue bottle just like this and you see it white and pooling up like that that's how you know you have enough glue on there right down the center line and then along the shoulders of the road bed and now we wait for for that to dry while I'm waiting for that to dry I can go ahead and glue this part of the hill on I'll still be able to access most of the tunnel interior from behind now I can blend the top and bottom together just a little bit of this Flex paste and I'll come back and paint all this to match once it dries but right now I'm going start work on this retaining wall up here I want to build this in place and I've started by laying another 12 by12 up here then I've got some o30 scale ties that make up this little piece of retaining wall that I'm recycling from the last version of Calico town I like about building this stuff in place is I can just press right down into the foam get a nice [Music] fit now I want to have like a mongr assortment of posts holding this back different sizes have some be round some be square [Music] now I want to give that retaining wall a reason to be there I'm going to dig into my collection of real rocks and dirt back fill this just kind of drop it on and let the Rocks fall where they may some smaller rocks I'll clean those off the track before I start gluing things down now I've got some lighter blond colored sand mix in with that lighten things up a little bit once again a little wet water and dribble on the diluted white [Music] glue now I've let everything dry overnight I'm just going to come back with my shop back and pick up any loose pieces of ballast or rock that might have fallen down between the rails now I just want to come back with my colored chocks add a final bit of weathering coloring to the Rocks you put this real Rock and dirt on here a lot of times it dries a little bit darker than it originally went on so I want to lighten it up a little bit blend it in with the foam Rock work a little bit better colors I'm using here is a little bit of terracotta mixed with white just to give it that kind of blonde rock look I'll take some pure black chalk I add some smoke and sitot stains here at the top of the tunnel something you always see on Tunnel portals even though the uh locomotives on the gold field in Calico are oil fired still going to see a lot of soot built up here on the top of the tunnel I'll take that same black and bring it down here along the center of the track represent so and oil stains passing trains I can also use chocks to gray down and desaturate the ballast just a little bit okay that's pretty good hit it all with some uh clear matte finish I'll just clean the rail head with some minerals Spirits got all that glue and chalk and dirt off of there and I think we can put the back half of the tunnel on now now I want to add some weeds and desert plants and things just poke into the foam with a pencil dab that in a little bit of Eileen's tacky glue push it down in there this is some Woodland scenix field grass I'm using here for weeds crummy old paint brushes work well too now I want to add some ground foam here and there for some larger bushes this is some dark green ground foam that I dusted with just just a light gray spray to uh desaturated a little bit i' got a little yucka here from jtt scenery products which helps to establish the Mojave Desert local I'm also going to be adding some Joshua trees a little bit later on so that's going to be a whole another video last but not least I've got some uh prickly pear cactus here from Pegasus Scale Models well all right let's get a train running through here now and see how it all comes together [Music] [Applause] [Music] and that's a wrap on the tunnel project I want to thank you all so much for joining me today for this first bit of new scenery on the o30 Goldfield in Calico I had a lot of fun putting it all together of course there's a lot more still to do on this layout so if it's your first time here I hope you will subscribe and hit that notification Bell so YouTube will let you know when new videos are coming from Thunder maesa studio in the meantime you can also follow us over on Instagram at thunder. Mesa and see the resources available on the Thunder Mesa Studio website at Thunder mesa. Studio as always a huge shout out and a big thank you to our patreon members who helped to make these videos possible until next time keep moving forward my friends adios for now [Music]