The GIRR is a fantasy railroad with the concept of being loosely connected to the Santa Fe in the 1950's. This connection is made for a few convenient reasons. The Santa Fe was one of three Class 1 railroads (along with UP and SP) in the Los Angeles area. The only tracks that went anywhere near my childhood home are those of the LA Harbor Sub of the former Santa Fe. These are the real trains that I saw on a more or less regular basis as I was growing up, hence, I like the Santa Fe. Many other people like the Santa Fe as well so that the large scale train manufacturer's will usually paint a version of anything that they make in Santa Fe colors of some kind even if there was no prototype for that particular piece of equipment on the real Santa Fe. This means that there is a wide variety of equipment available, already painted for the Santa Fe so that I can get and use a wide variety equipment without needing to even think about repainting it. Further, Santa Fe paint schemes are generally considered attractive.
When it came to designing a passenger station for the GIRR, it was natural for me to select the style that the Santa Fe used all over southern California. This is the California Mission Style. The photo is of a station in the San Gabriel Valley, the Monrovia station. I picked this one to start with because it has the attributes that I wanted and it is not too large. However, I didn't intend to model this particular station, just one sort of like it.
In the case of the GIRR, a station site was reserved next to a siding on a main line. However, the site is unusually constrained by a switch back track that eventually leads to a freight shed and warehouse. I was easily able to rationalize having a track on BOTH sides of the station by deciding that it would double as another passenger loading track for local equipment, in this case a Doodlebug. Therefore I needed a double sided station. The arched breezeway of a typical mission style station would be needed on both sides. I decided to build two breezeway structures and offset a longer one to the passenger siding and a shorter one to parallel the Doodlebug track. This also fit the area available which is loosely shaped as a parallelogram.
This is pretty much the extent of the original plan for the station. I got the general concept down. Then I measured the space available and decided on the size of the arches and started to work. I estimated that the building would be large anyway and that's the way it turned out. I wanted it to be imposing and that's what I got.
This is the frame of the shorter arched breezeway after initial assembly. The corners are internally braced with Jigstones, also cast in RapidSet. The whole structure is built in three separate pieces, the two breezeways and the central building. This is so that no individual piece gets too large or heavy. The three pieces will be set together on Wonderboard bases on the layout.
The construction method uses WonderBoard and RapidSet Cement All. I don't intended to use any wood and minimal adhesives in this structure, although I might use some cast resin window frames and doors on the side that visitors will see which is also the side that will get little direct sun.
Concrete has demonstrated it's stability out in the weather in other structures that I have built. The structures are a little heavy, and it is hard to model in fine detail, but for a 10' rule building that will never come indoors, the weather resistance is the overriding factor. When it absolutely, positively has to sit there and take it, it's hard to beat concrete.
The RapidSet is used uncolored for structural joints that cannot be seen or surfaces that are supposed to represent concrete. Since many paints won't hold their color out of doors, I use stucco tint to color the RapidSet where I want color. Stucco tints are especially selected to be sun stable and not fade. They typically come in a 14 oz bag where the whole bag is intended to be mixed with a standard 90 lb bag of stucco base. This is about 1% by weight.
RapidSet is off white in color, pretty close to the pure white of stucco base. Other cements, like Portland cement and Quikrete are too dark in color and don't tint as well. I use the Rapid set tinted to 1.4% by weight for the roof tiles (red iron oxide) and 1% by weight for the wall coatings (terra cotta). I have had no difficulty color matching batches of tinted RapidSet. I mix by weight on a 5 lb postal scale that has 0.1 oz resolution. The batches are 48 oz of dry cement to 0.5 or 0.7 oz of tint. The precision of the scale is good enough to match colors between batches. The weighed RapidSet and tint are dry mixed in a gallon size Ziploc freezer bag and stored sealed until needed. The color won't show until water is added to the mix.
Hand protection is a must when working with cement, the cement will draw all the moisture from your skin. Use Nitrile exam gloves, available at any pharmacy. These hold up much better than latex gloves. I mix what I can use in a few minutes work in a paper or plastic cup using a 4-1/2" coffee stirrer (popsicle stick) as a mixing tool. Water is supplied from a pump spray bottle. It is easy to control the amount of water applied simply by counting the pumps. Often, the mixture will start to set in the mixing cup and get too thick. An additional spray of water into the cup will soften the mixture again to allow it all to be used. Discard the cup, stirrer and gloves after each session. Coffee stirrers are available very cheaply in boxes of 1000 or more at restaurant supply stores like Smart and Final.
The subroof is also Wonderboard, braced with small cutoffs of Wonderboard. The cutoffs conveniently came from shaping the ends of the breezeway. The subroof is designed to sit flush with the ends of the structure, the roof tiles will be attached to the subroof with yet more RapidSet. I initially decided not to allow the subroof to extend outward by sitting on top of the structure because it would have been just too thick and disguising the edges would have been difficult. The roof tiles then overhang the whole structure. However, the tiles are brittle and then need the support of the subroof so on the next parts of the structure, I am going to extend the subroof to nearly match the size of the roof tile array.
This is a roofing tile. This particular one is a reject due to the bubbles and the fact that it is warped. These tile sections tend to warp in the mold as they cure so I have to weight the edges of the mold to get flat sections. The mold was made using a piece of vacuum formed styrene sheet as the master.
I found that I could weight the edges of the mold with some bricks and the parts would come out flat, but they would often crack while curing. The cement wants to shrink and this was causing the warpage, but when the mold is constrained, the parts just crack instead. I found that by spraying a layer of water on top of the freshly poured concrete mix, the parts do not crack. I'm not sure exactly why, but it works.
The bubbles are easiest to work out if some water is sprayed in the mold before some of the wet cement is poured in. Only about 1/3 of the mix should be poured and then spread throughout the mold. Then the thin layer is poked and prodded with a coffee stirrer to work out the bubbles that are still adhering to the mold. Then the rest of the mix can be poured on and leveled with the coffee stirrer by skiving off any excess cement. I've become pretty accurate in determining how much dry mix to use so that the mold is just filled and there is virtually nothing left in the cup when I am done pouring.
It takes 2 hours for a roof tile to set up hard enough to be demolded without serious risk of breakage. Even then, the part is still somewhat "green" and is darker in color than it will be when the excess water fully evaporates. However, this is the time to use a file to clean up the flash from the edges. Flash can still be filed off after the part is fully set, but it's harder on the file.
The subroof is assembled and ready to accept the tiles. It'll take a day or two of casting the tiles to get enough to cover this part. It'll take a row of tiles 1 and 1/2 tiles high to cover one side of the roof, 3 and 1/2 tiles wide. I therefore have to break some cast tiles (difficult) or cause some defect that makes them break at the right spot. I found that I could place a narrow coffee stirrer stick (trimmed to length) half way across the mold to create a part line where the full tile will easily break. I also have enough already broken parts such that I will get the right size parts one way or another.
The tiles will be grouted to the sub roof with the a mix of mortar made from the same tinted RapidSet that the parts are cast in to blend them together and, hopefully, hide the boundaries of the individual tiles. Also, some minor casting defects can be filled in at the same time.
The top row of tiles are really half height tiles. The end that doesn't overhang uses 2/3 width tiles. It was too hard to break them cleanly so instead I pour them with a separator in them. This setup makes the half height, 2/3 width tiles. If I leave out the short sticks, it makes the half height tiles. The bubbles in the mold have turned out to not be much of a problem. The cement doesn't actually go into the bubbles anyway. Eventually, I made another mold, this time being more careful to avoid the bubbles.
Almost all the tiles on one side are attached and grouted. I broke my last half height tile. I'm waiting for a full size tile in the mold to set before I can make another half height tile. Then, the roof on this side will be complete and I'll do the other side. Grouting the parts together turned out to be pretty easy. I mortar behind the tiles with a thick layer of tinted Rapid set and place the tile. After just a couple of seconds, it'll stick in place well enough so that I can grout around the edges in in the gaps between the tiles. I make a big mess this way but in 5 minutes, the cement has set up enough so that I can start scraping the excess off with old dental tools. The joints clean up quite well. The last tile on the end has been on there for less than 10 minutes. I've cleaned up the joints around it and it isn't going anywhere.
This is the almost completed smaller breezeway. After the other parts of the buildings are done, I'll attached it to a base but I want to see how it will lay out before I decided on the final size for the base.
Next up, the main building. I've revised my plan just a little bit to make the roof an integer number of tiles in both directions. This will avoid the hassle of casting them in partial sections.
WonderBoard doesn't lend itself to really fine construction details, but one detail that I wanted was the round window often seen in mission style architecture. A sample can be seen in the lead photo on this page.
A 1" hole was cut in the front face of the station, see the method at WonderBoard Tips, and ridged with tinted wet cement. The cement was allowed to set for a few minutes and shaped by hand. Two pieces of 18 ga copper wire were pressed into the wet cement. The detail isn't wonderful, but it will look fine at 10'. I'll eventually paint the wires with Floquil Engine Black.
The windows can't really be done in cement so I am using resin castings. These are painted with Rustoleum with a layer of primer underneath the paint. The holes for the window frames were made with the scribe and pound method. This leaves a pretty rough cut but the edges clean up pretty well with tinted RapidSet. The hole was finally sized with a file if it was too small or by applying some RapidSet and allowing it to partially set up. Then the test window (cast thicker than the real windows for strength) was simply pressed through to skive off any excess cement.
The doors on the station are cement castings made from a homemade master. They were then painted with the same Rustoleum as the windows and slightly detailed with some Floquil Engine Black on the hinges. Two of these will be attached to the front of the station with more cement and two more to the sides leading to the breezeways.
This is the whole front of the main station building before being overcoated with stucco. The doors and windows are in place. The windows have "shadow boxes" behind them in the form of slabs of Wonderboard painted black.
Even though the doors are cement, they are painted. The window frames are Alumilite resin castings and painted. I tried to figure a way to secure the frames with just cement, but it just didn't work out. I used a fillet of plumber's epoxy behind each window frame to fix them in place. The doors are attached with cement.
The next step is to mask the doors and windows and stucco all of the wall panels for the stations and assemble the core. Then the removable roof will be assembled and tiled. With the exception of the base, this will complete the core.
I don't intend to illuminate this building but if I ever change my mind, I can break out the view blockers and install individual room scenes or a bigger shadow box and lamps.
This is the assembled core building. It is bigger than I thought it would be, but at least the doors are to scale. The corners look dark because they are wet, I just finished applying a coat of stucco to fill in the joints between the front and side walls. I also added some interior corner braces, one can be seen at the back. I do not want these joints to break so it will sit just as it is overnight before I touch it. Then I'll carefully turn it over and add more cement under the corner braces.
There is no detail on the sides or back now. I'll add two doors, inside the breezeways, once I determine their final placement. There will never be any detail on the backside. The roof is next.
The subroof is sized to accept 4 roof tiles wide by 3 high minus a quarter inch on each side so that the tiles overhang the subroof by just a little bit. To make sure that it has the right angle and position, I assembled the subroof upside down using the building core as a fixture. The subroof panels are supported by bricks used as props.
The interior of the subroof is braced with the cutoffs from the front and rear walls of the station core. It's all held together with RapidSet. Once the subroof has set up, the building will be lifted off and the subroof will be propped upright to allow the roofing tiles to be grouted in place.
The roof is close to complete in this photo. The other side is missing four tiles, it'll take just a little while longer to finish. The grouted areas are still wet so that they show up, when the roof fully dries, the joints will nearly vanish.
This part of the assembly goes really fast, it took less than 15 minutes to install the tiles on this side. The grouting is done in one pass. It leaves a pretty big mess of grout where it doesn't belong. As soon as the last joint is grouted, I start scraping off the excess grout, working across the grout lines in the same order that they were applied.
This is the unfinished side just to show that the tile split lines are plenty obvious until grouted. Compare it to the previous photo.
The ridge line across the top of the roof is simply a bead of tinted Rapid set applied and formed by hand, then cleaned up with a sculpting tool.
Just for grins, I weighed the roof and the core. The roof, in its incomplete state, weighs 16 lbs. That will probably grow by at least a pound when it is finished. Except for the base, the core is finished, it weighs 21 lbs. I am guessing that the base will weigh about 5 lbs so the total central structure should be about 43 lbs. This does not include the breezeways. I am not too concerned about this building blowing away in the wind.
Two thirds of the project is complete. I've decided not to permanently attach the structures to the bases, they are strong enough as they are and they don't need more weight. I still have to clean up the edges of the base sections, pave them with cement and scribe some cracks in the paving. I'm also going to cut a triangular shaped planter in the tapered section next to the track.
This is the longer breezeway ready for roofing tiles. It took about a day to build it up to this point. When I have enough tiles for the whole thing, they'll all go on in about an hour and the building will be finished.
I was still having yield problems with the partial tiles, the sticks in the mold helped, but they weren't an adequate solution. Then it occurred to me that I could just score the cast part in the green state to make a break line. I waited an hour for the part to partially set but still be soft and scribed the back with a utility knife, but I found that I could actually cut all the way through the part down to the mold. Then I let the part set fully hard and demolded it. It worked fine and at that point, the yield was nearly 100%.
Once I had enough roof tiles, the rest of it went quickly. By the next day, it was all done. I also paved the bases with "cement" and scribed some cracks. I cut a hole for a planter and lined it with Jigstones.
I used just short of two full sheets of 1/4" Wonderboard and 50 lbs of RapidSet on this project. There is little else in it except for 8 Alumilite window frames.
This project has been in the plans for 10 years. It took several months of experiments to develop the processes I would use before I started construction. Then it took 2 weeks to actually build the thing, but it's done.
After I had run some trains to the station I realized that the platform wasn't long enough so I added about 3' of simple platform to the north end.
However, I discovered another minor miscalculation. I had set the platforms right close to the rails, too close. While the trains clear them fine, my pole sander and track cleaning cars do not. I need to move them back by about 3/8" from the edge of the rail to allow a little clearance. This may involve a little grinding on the edges of the platforms and a little repositioning.
This page has been accessed times since 23 Mar 08.
© 2008 George Schreyer
Created 23 Mar 08
Last Updated June 10, 2008