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The Freight Cars That Dave Built (or is building)

The models below represent my work from about 2001 when I began my transition from Gauge 3, 1:22.5 scale to F gauge, 1:20.3 scale. So far I have built about four standard gauge cars in 1:20.3 (as of 10-1-09), but several others are in the planning or construction phase. For several years during this period (2003-2005), I did not have a viable workshop, so what hobby time I did have was spent on setting up my 23' x 25' shop. And each new little person (we are working up to #4 due in March of 2010) takes plenty of time, but my girls love trains--just like Dad--and help when they can. As of late, my hobby time has mainly been going into R&D with respect to freight car trucks and what I hope will eventually become a couple of kit cars (see below).

Want to build a freight car with me? I oftentimes have some spare parts and welcome corroboration. Let's do it together! Half the time--twice the fun!

At left: Who says girls don't like trains? Here is my oldest, Sarah, a six-and-a-half-year-old driving a 7.5" gauge coal fired  live steam 2-10-0 owned by my friend Scott Reedy of Columbia, Tennessee at the Mid-South Live Steamer's track (May 2009).

Tools & Techniques

Since beginning to develop standard gauge modeling in F scale around 2001, the construction techniques that I have used in building freight cars has correspondingly evolved with the level of sophistication of the tools in my shop as well as the development of my own modeling skills. My earliest F scale cars were styrene & ABS one-off models, built in much the same way as my Gauge 3 rolling stock. Since then, however, I have progressed from hand-cut, hand-filed, and manually milled components to CAD drawn, laser cut & CNC machined ones. The reason is fairly simple: My long term goal is to build either fleets of freight cars for my own use and/or to move into short-run kit production (even now I can envision 100 car coal drags on a 1/20th scale Norfolk & Western outdoor railroad with As, Js, Mollies and all the rest--but I digress!). The three 40' American Car & Foundry flats at right are examples of my older one-off modeling techniques and are typical of what one man with a modest collection of hand tools can accomplish in styrene. By way of contrast, the Cass Scenic Railroad / Mower Lumber Co. logging flats below are illustrative of applying CAD/CAM technology to model-making and show how one man with the right software, access to a laser cutter, and a miniature table saw can get into building fleets of wooden rolling stock. Future additions to this page will include discussions of reproducing steel car prototypes through the application of rapid prototyping (RP) technology as well as making large, carbody sized urethane castings. For a foretaste of the latter, check out both Bob Uniack's gallery, as well as Barry Bog's Freight Cars, located elsewhere on this site.

The One-Off Models

The one-off models were constructed from a combination of styrene and ABS sheet as well as Plastruct structural shapes (mainly channels, angles and H columns) to represent real world steel components, whereas either basswood or western cedar was used to represent wooden ones. A smattering of fabricated brass bits and pieces along with detail parts from the usual sources (Trackside Details, Precision Scale, Hartford Large Scale Products and Ozark Miniatures) complete the models. Typically I have worked from drawings published in the model railway press for these cars, photostaticly enlarged. In this respect, Hundman Publishing's flagship magazine Mainline Modeler (now defunct) has been the single most best depository of scale freight car drawings in the industry (Thank you, Mr. Hundman, for such a great magazine!). I have simply laid out the enlarged drawings on my workbench or drafting table, and then measured, scribed and cut plastic to fit.

Speaking of fit, I've tried to keep components accurate not only by measuring twice with a scale rule and then carefully scribing lines using a machinist's square; but with structural shapes, before making any cuts with a razor saw, I allow an extra bit of material, cut, and then sand down to spec using a Micro-Mark rotary disc sander, checking as I go with either a 6" or 12" dial caliper. For really long lengths of plastic (12" and more), vernier calipers are available--and for those with the bucks, even larger sets of dial calipers. CA ("super-glue") usually holds the whole thing together, though I have also used Plastruct's Plastic Weld--basically just methyl ethyl ketone (MEK)--which is fine for joining large flat surfaces, but poor for butt joints or wherever minor irregularities between components result in gaps. In that case a gap-filling CA is far superior.

Faking Rivets

From the earliest days of the steel car era until the late 40s and early 1950s, rivets were the preferred method of holding steel plates together, in preference to bolts, both of which have been largely superseded by welding. So how does one duplicate all those hundreds of rivet heads found on a typical steam era freight car? There are several methods one might use: Thin plastic or brass is readily embossed with the right tools, imported brass models and many British freight car kits typically use photographically etched brass, actual miniature rivets are even available. But the method I settled on has been jig drilling properly spaced holes for small Peco brand track nails or sequin dress pins, and then with a dab of CA, pushing them home. Where larger rivet heads are needed, I have used both Atlas brand track nails as well as brass escutcheon pins. My drill guides are just strips of brass stock (K&S or Special Shapes), drilled using a small center drill mounted in a Jacobs chuck my mill-drill. I have made several sizes of guide, each with different spacing of holes, sized for the job. For instance, the flat car above required both a small handheld jig for spacing underbody rivets whereas a long brass drill guide was made to locate the grab irons & stake pockets accurately. The actual drilling of the rivet holes is done with a pin vise, using a bit several thousands of an inch under the diameter of the nail's shaft. A Dremel tool tends to run too fast for this sort of work, melting the plastic rather than drilling it; though other brands of handheld tool (Foredom for instance) can be slowed down to do the job properly.     

Stirrup Steps

I should probably admit that the methodology I use for making small batches of stirrup steps is probably inaccessible to most other modelers; and maybe with a bit more patience I could have come up with acceptable results from bending and forming brass bar stock, but my technique is to cut stirrup steps out of solid brass sheet (of the appropriate thickness) with my Japax wire EDM. What is wire EDM? It's computer driven magic--think of an electronic bandsaw where a small current of electricity is used instead of a blade to literally burn metal from a workpiece within a few ten-thousandths of an inch, all guided by a computer, and that's wire EDM. Pretty much if I can drawn it in CAD, then I can cut it out of any conductive material. Stirrups steps so formed have tight "bends" and fit perfectly--and being made out of brass, they're a lot tougher than cast white metal ones. Of course, they also need to be drilled at the proper location of the strap so as to attach to the bottom or side of one's car; and so I set up a special drilling jig in my mill-drill for this job, also cut on the wire EDM (see pics at upper right). For securing stirrup steps to the cars, I use Phil Dippel's (a.k.a Phil's Narrow Gauge) exquisitely formed square head brass pins.

American Car & Foundry 40' Fishbelly Center Sill Flat Cars (2001, 2005-09)

The AC&F 40' flats were work-a-day utility vehicles built for many roads. The Mainline Modeler article which was the genesis of these models focused on a series of cars built for the Atlantic Coast Line, but similar cars could be found plying the rails of the D&RGW (note the narrow gauge equipment atop the standard gauge flats, below) and other lines wherever a platform car of modest capacity was required. Given the Bettendorf T-section trucks which originally equipped these flats, and the lack of fishbelly sides sills to compliment their sturdy built-up fishbelly center sills, these were roughly 80,000 lbs capacity cars. I originally chose this prototype because, well, the plans were available and it looked relatively simple. Once again, my thanks go to you, Mr. Hundman, the publisher of Mainline Modeler, and to Mark Montague, the article's author.

Photo Sources: The Best of Mainline Modeler's Freight Cars, Vol. 3 (drawing & ACL pics), Denver Public Library, Western history collection (D&RGW pics).


The First Standard Gauge Flat Car In F Scale

In early 2001 I began thinking about leaving Gauge 3 in favor of standard gauge modeling in F scale (15mm = 1 foot, or as it is more commonly know, 1:20.3). That spring I took the plunge when I commissioned Gary Watkins (a.k.a Sierra Valley Enterprises) to produce 500 F gauge wheelsets. My friend Don Niday and I also built a modular layout in three sections, totaling 25' long, for display at the 2001 NMRA Convention in St. Louis (see at right). At the same time, Jeff Saxton was burning the first laser-cut standard gauge wooden boxcar kit in 1:20.3 (also below). And so now I needed something to put all those wheelsets under, but what? And then an old favorite came to mind: Why not build an F scale version of the same American Car & Foundry WWI era flat such as I had already been building in 1:22.5 scale, Gauge 3? My first scratchbuilding project (circa 1994) had been a Gauge 3 model of this car, begun on a dining room table during my days at Covenant  Seminary; and now a batch of seven of these cars was on my workbench in very stages of construction. With a little judicious cutting and refitting and a few new parts, an F scale version would not be too hard to come by, right?

And The Real Builder Is . . .

Well, not too hard; and here, I must give credit where credit is due: The first F scale standard gauge flat was put together, not by me in my Knoxville, TN workshop, but at the 2001 NMRA National Train Show by my dear wife Helen using leftover Gauge 3 parts! To be candid, Helen is also a much faster riveter and handlayer of track than myself; and I don't think our booth could have had a better advertisement for F scale, certainly not a more attractive one, than her, especially compared to those two goons above.

The First Standard Gauge Freight Car Truck in F Scale

I am sorry to report that there are no photos of the construction of the very first F scale standard gauge flat car beyond a few pics of its trucks, but here's a bit of history for you. The trucks on this car where made from cast iron side frames better than 75 years old. Trucks always seem to be the bugbear of many scratchbuilding projects, since they are not easily handmade, particularly the cast steel variety, and until recently none existed in F scale. But in 2000 I came across a man in Johnson City, Tennessee who had the largest collection of H. J. Coventry B&O P7 Pacific castings and half-built models of anyone I ever met (a Gauge 3 live steamer, Mr. Jim Hadden, now has them at his home in Utah). The Johnson City man had two spare sets of tender truck side frames--no bolsters or spring planks--just the raw, un-machined, grey iron side frames dating from the late 1920s or early 30s. With a bit of drilling, filing & fabricating of a new brass bolster and spring plank, the result was the first freight car truck in 1:20.3 standard gauge (above right)! By the way, those wheelsets are also unique, because they were from Gary Raymond who in the early days of F scale, about 1999 or 2000, manufactured a small production run of nickelplated 33' wheelsets, some of which he also regauged and sold as 36" wheelsets in 1:22.5 scale, Gauge 3.

The Completed Car

This first car was made for the most part like the two subsequent ones below, using .060" ABS sheet cut to simulate the fishbelly center sills and 5/8" Plastruct channels to represent the prototype's 10" side sills. A smattering of additional Plastruct Ts, channels, and angles complete the underframe. Kadee "G scale" couplers were used along with the usual assortment of commercially available white metal detail parts. The deck is basswood, stained with a wash of alcohol and India ink, and then distressed with a file card. The deck boards were glued with Titebond II carpenter's glue to their stringers. The trucks and frame were painted and weathered separately by my friend Don Niday (who now owns the car). A load of 33" Gauge 3 wheelsets is pictured with the car below on Don's dual gauge indoor railroad, The Crofut & Iron Creek.

Cars #2 and #3

I began two additional AC&F 40' flats sometime in late 2002, having completed the last of my Gauge 3 freight cars that Fall. These cars were originally intended for my own railroad, and so never made into any advertisements or anything so grandiose as a catalogue. Sarah our oldest child arrived early that November, and so the underframes of these cars sat around for quite some time unfinished. Subsequent correspondence with an English garden railroader, Mr. John Masters, and a former Gauge 3 customer, Mr. Ernie Schieferstein, convinced me to sell both cars, the former completely painted and weathered, the latter as a semi-kit.

    Bettendorf T-Section Trucks By Bob Uniack

These next generation cars were built using the same ABS sheet, milled or filed to shape, and Plastruct channels as the earlier Gauge 3 cars, but with a few added refinements. First, the trucks actually are Bettendorf T-sections, patterned after the original equipment used on these cars, though subsequent shopping replaced the prototype ones with stronger u-section designs. I have Mr. Bob Uniack to thank for these 1/20th scale cast urethane trucks. Around 2004 or so, Bob began work on an F scale Southern Pacific B-50-14 outside braced boxcar, having already built several 1:32 scale models of the same car (you can view more of his work here). Bob made styrene patterns for these unique, early cast steel trucks based upon drawings published in Mainline Modeler and upon his own measurements of the real McCoy--and he was kind enough to share urethane copies with me. Bob used my 33" plain steel wheelsets along with Hartford Products large springs to complete the trucks.

A Question of Couplers

At some point, every large-scaler is faced with the question of what brand of coupler to use on his rolling stock, and in particular if he needs to replace the stock commercial couplers he received on his ready-to-run models with something better looking or more reliable. For my Gauge 3 models, I consistently used the earlier Kadee "G scale" couplers since they operate well and look reasonably good, minus their short steel uncoupling pins which look vaguely like an air hose minus its glad hand (these I usually cut off, destroying of course their delayed action uncoupling feature, which would never have worked anyway given the coupler center height requirements in Gauge 3). For the initial F scale flat, I had again used Kadees; but in 1/20th scale, they are perhaps a little undersize--plus--I wanted a coupler that could utilize a functional uncoupler lift bar. And here, Accucraft had the right injection molded plastic product, except for one thing: The Accucraft coupler, being intended for use on tight radius, narrow gauge curves, has a long shank which is pivoted from the vary front of the Accucraft draft gear box. The solution was to discard most of the Accucraft draft gear box's molded-in striker plate, and create my own from brass. The end result is a coupler with less exposed shank and a more prototypical looking striker plate, soldered up from brass bits and pieces, most of which were cut on my wire EDM.  

Construction Pics

Below are various views in the construction of these two cars. As you can tell from the dates, this has been an on-again-off-again project over the last several years. My thanks go to my friend Barry Bogs for the AB brake system triple valve casting and for copies in urethane of the AB reservoir I originally made for Gauge 3. This batch of photos basically brings us up to mid-2007.


The Completed Cars  (To Be Continued--last update 10-14-09)

36' Wooden Truss-rod Boxcars (2001-2002)

The 36' foot wooden truss-rod boxcar was a staple of late 19th and early 20th century railroading. Some of these ubiquitous house cars survived into the late steam era in maintenance-of-way use, though cars with archbar trucks and wooden underframes had long since been outlawed from interchange service. A very few examples survived into the preservation era (the Soo Line car at right, for instance, at the Mid-Continent Railway Museum), but the number of truss-rod equipped standard gauge wooden boxcars still in existence can be counted on one hand.

These wooden truss-rod cars are to be distinguished from their close cousins, the composite cars built between 1900 and the end of wood car construction in the 1920s. The distinguishing factor here is the greater use of steel in the composite cars, mainly in terms of steel underframes and the frequent application of pressed steel ends. These sorts of cars are much more common in preservation and fall into two basic categories: the double-sheathed cars and the single-sheathed designs, the latter being readily distinguished by their exposed "outside" steel bracing. For instance, the USRA 40' single-sheathed boxcar and the Fowler outside braced design (and Fowler clones such as the D&RGW car below left) used wood sheathing on the inside of the car in order to protect the cargo--not the carbody's supporting structure--from the elements. In contrast, the smooth sided double-sheathed designs, such as the pre-WWI D&RGW 36' beet boxcars (below right) used wood sheathing to protect both the car's structural framework as well its cargo from the elements, and hence, were "double" sheathed on both sides of their bracing. In either case, the wood sheathing is always protective, not structural in its function (a feature that further distinguished wooden and composite car construction from later steel cars where the steel skin itself is often load bearing, not merely protective of car and cargo!).

And then there are the oddities which are really transitional designs between the wood car and the 100% steel car eras. Some roads, such as the Delaware and Hudson, maintained substantial 36' steel underframe, wooden boxcar fleets right through WWII (note the D&H car below at the Railroad Museum of Pennsylvania). Some of these composite designs, while at first glance looking like wooden truss-rod cars, in fact are not, including the odd-ball Southern Railway 36 footers of the early 1920s which used both steel underframes as well as truss-rods (below, center). The D&RGW also had a transitional design built in 1909 which employed a steel underframe, steel interior bracing, and were double sheathed. Subsequent rebuilds of these cars resulted in their wooden ends being replaced with Murphy pressed steel ones. Several examples of these odd 36' composite cars survive, one at the Galveston Railroad Museum and another at the Arizona Railroad Museum (below right). Sadly, none of the offbeat 36' Southern Railway cars survive.

 Photo Sources (Left to Right): D&RGW Fowler clone (Barry Bogs); D&H 36' (DQ); SR 36' (Ted Culotta); D&RGW 36' beet boxcar (GRM & ARM websites)

The First Standard Gauge Box Car "Kit" In F Scale

So why choose a 36' wooden truss-rod car to become the first boxcar kit in F scale? The answer is simple. It's a lot easier to model an all wood car without having to mimic either a steel underframe or Z-profile outside braces, especially if one has a kit in mind. And . . in the Spring of 2001, "Engineer" Jeff Saxton, who at that time was employed by American Model Builders in St. Louis where he had access to a laser cutter, began developing a "budget" Fn3 boxcar based upon the 36' cars of the Florence and Cripple Creek (several of which still exist after changing hands numerous times during their service careers). Engineer Jeff was persuaded to scale up the F&CC's dimensions to standard gauge proportions (roughly along the lines of the NYC or the SR cars above). Since I now had plenty of 33" wheelsets, my part was to provide archbar trucks. The other member of this collaborative effort, Bob Hartford, provided suitable detail parts from his sizable range of castings.

The First Standard Gauge Archbar Trucks in F Scale

Since at that time I had few machine tools, the trucks I made were an adaptation of some white metal sideframes sold by Mr. Steve King who actually marketed them for Maine 2' gauge modeling in 7/8" scale using Gauge 1 track! With some rudimentary Plastruct I-beam bolsters and Harford Products springs--volah!--the first archbar trucks in 1:20.3 standard gauge were rolling down my test track. Well, as with most compromises, there were, well, compromises; and that was particularly the case here. In F scale this truck's wheelbase is a bit long, about 5'-8", but with nothing else readily available, and a NMRA Convention to display at in July of 2001, this was an acceptable compromise for most parties involved. The results are pictured above.      

About 25 car kits were burned by Engineer Jeff in the first production run. My friend Don Niday (Iron Creek Shops) commissioned a few more for himself on the side. I built one car; whereas Don built several and has kept one: painted, decorated & weathered to resemble a Southern Railway prototype (see pics at right). Several other cars were done up in D&RGW "flying" Rio Grande lettering (see below, middle). Both sets of decals were prepared by our mutual friend, Mr. James Engle, on an ALPs printer. The SR reporting marks came from the equipment diagram at right, itself kindly provided by the Southern Railway Historical Association. I have no idea how many of the other production kits actually got built. Anyway, my car went to California and back in the early days of F Gauge to test exact scale wheelsets made by my friend Gary Raymond (and were declared a winner--on good track). It has since been sold. Don had intended to re-introduce the Saxton kit in 2008 with a few refinements and a choice of either the same long wheelbase archbar trucks or his own cast urethane 50 ton Bettendorf trucks, but the laser cutter he was using went out of business. Well, such is the case with a lot of one man garage operations.

In the spring of 2007, I began making a pattern for an appropriate short 5'-0" wheelbase archbar truck, based upon the 30 ton capacity trucks which equip the two Ma & Pa 36' wooden boxcars at the Strasburg Railroad. When completed, they will be available in white metal and should come with a mating carbody bolster. In the future, I would like to produce a car kit more specific to a particular prototype (such as the Ma & Pa boxcar with its double-sheathed body, twin steel I-beam center sills and truss-rods), but my speculation is that a late-steam era 40' composite car such as the USRA single-sheathed, outside braced boxcar would be far more commonplace . . . and hence marketable. Anyway, my brass casting patterns for a 50 ton USRA Andrews trucks are very nearly complete, awaiting only assembly and a bolster (see pic above).

Dave's Car (Sold)

Don's 1st Two Cars (sold)

Don's Keeper (w/ SR Reporting Marks)

40' Cass Scenic RR Wooden Log Car
(2002-2004, 2009)

Originally built for the U.S. Navy and then sold to the West Virginia Paper & Pulp Co. around WWI (and passed down through successors Greenbrier, Cheat & Elk RR, Mower Lumber Co. and of course, the current state owned tourist operation), the Cass Scenic Railroad logging flats are unique, not only in the sense that 40' wooden flats were rare (36 footers were far more common along with skeleton log cars, particularly in the west, but the Cass log flats also used large timbers in lieu of cast iron queen posts (see pics below). When tourist operations began at Cass in the 1960s, converted wooden log cars were the passenger hauling mainstay of the excursion program; but as time and rot took their toll, management began to replace them with converted steel skeleton log cars from the Meadow River logging operation. Only one wooden log flat remains today, at least in recognizable condition, with the trucks and iron components of several other cars resting in the overgrown weeds of the C&O siding just beyond the water tank. Even the one remaining log car has deteriorated to such a point in the seven years since my last visit that accurate measurements of many its wooden components would not be possible (compare the 2002 pic above and below right to the two 2009 pics below left).

The First Cumberland Kit--Maybe

In the Fall of 2002 my wife and I visited the Cass Scenic Railroad in West Virginia with the express purpose of photographing and measuring one of the few remaining standard gauge, truss-rod equipped wooden flat cars anywhere--and riding, of course, one of the Shay powered excursions up the mountain! This "research" trip began my first attempt at putting CAD & CAM technology to work building a 1/20th scale freight car, and hopefully, not just one, but a whole fleet of cars. The Cass log flats have been modeled before, most recently by Bachmann as part of their HO scale product line. The drawings below, however, are wholly my own--in fact they are representative of my earliest CAD work--and are based upon my own measurements and sketches of the one remaining log car (jotted down on site by my talented Help-Meet, at right), and compared with measurements and less detailed drawings published in both The Narrow Gauge & Short Line Gazette as well as the newsletter of The Mountain State Railroad & Logging Historical Association. As a modeling project, these flats are appropriate to the world of F scale because so many of us, if not modeling Colorado narrow gauge, are at least as likely to be modeling steam era logging operations. Eventually it is my goal to build not just several of these cars for myself and my friend Don Niday, but to offer it as a typical Hartford style craftsman's kit.

By the end of 2004 I had generated the 2D CAD drawings for this project and ripped some western cedar for the first two or three car's decking. My friend Phil's Dippel test cut the side sills, center sills and draft timbers on his laser cutter. The pics at right show the test cut centers & side sills along with the wooden queen posts laid out next to one of Bachmann's HO scale logging flats. Additional components remain to be drawn up in CAD include the swing down brake staffs and an appropriate K-brake cylinder.

40 Ton Archbar Trucks

I have now cut most of the bits and pieces which will eventually become casting patterns for the 40 ton capacity, 5'-0" wheelbase archbar trucks that equipped these cars. Here again, almost all my pattern work has been done using a 25 year old Japax wire EDM, based upon my own 2D CAD drawings. Pretty much if I can draw it, I can cut it. The archbars are each individually cut from stainless steel bar stock whereas the columns and journal boxes are cut from brass. Some mill work must be done on the columns and journal boxes; but once complete, the whole assembly will be bolted together with custom-made square headed shoulder bolts, turned on my own lathe. Another major component--the cast steel bolster--was made from six separate components cut--not bent to shape--from brass, and will be soldered together. The spring plank pattern is simply milled and drilled. A metal body bolster pattern remains to be made as of October 2009. All major truck patterns will then be sent either to an investment caster or to a white metal spin caster for copies.

Assembling the First Test "Kit"

Once the end sills and a few other odds and ends are cut on my Micro-Mark miniature table saw, I'll be ready to assemble the first car body. I will post updates on this part of the project in the coming months, DV.
(To Be Continued-last update 10-14-09)

D&RGW Dual Gauge Idler Car (2005, 2009)

Dual gauge track, where trains of varying gauge share at least one common rail, has never itself been very common in the United States. Only one Class I railroad has operated anything approaching an extensive network, namely the Denver & Rio Grande Western; but short lines such as the East Tennessee & Western North Carolina (or Tweetsie for short) and the East Broad Top have had substantial dual gauge interchanges. Lumber outfits such as the West Side in California also made limited use of dual gauge trackage, mainly around large saw mills. The most common dual gauge trackage has consisted of three rails spaced at 4'-8" and 3' intervals, though some special trackwork--such as turntables, ash pits, and their approaches--have used four rather than three rails in order to center up a narrow gauge car or locomotive between the standard gauge rails (see the turntable pics below left). Once there were substantial dual gauge yards at Alamosa, Colorado and Johnson City, Tennessee; but now only the East Broad Tops's surreally overgrown yard at Mt. Union, PA still exists. Dual gauge yards themselves presented unique challenges to both the track gangs who built them as well as the train crews who operated them. For instance, how does one switch a cut of narrow gauge freight cars with a standard gauge locomotive, or vice-versa, if that's all one has on hand?


Photo Sources (Left to Right): Colorado RR Museum turntable--Kevin Strong; Dual gauge yard & turntable at Alamosa &  NG Diesel #50--from John West's Narrow Gauge Memories; D&RGW V0 660, Alco S2 & GE 44 Tonner--Denver Public Library

 The full size railroads came up with several working solutions to the problem of dual gauge operations. Here are the most common:

٭ Manually Offset Pilot Coupler: The Tweetsie made use of a pilot mounted, swing motion coupler that could be offset to either the right or the left as track conditions required (see the pics of narrow gauge 0-8-0 #7 and 4-6-0 #11 at right). It is not clear if any coupler center height adjustment was possible with this particular design.
Photo Sources: ET&WNC narrow gauge locos #7 & #11--from Ken Riddle's Cy Crumley Scrapbook

٭ Pneumatically Offset Pilot Coupler: The D&RGW refined the offset coupler device by adding an air cylinder so that the single pilot mounted coupler could be raised, lowered, or shifted sideways pneumatically.  This was the D&RGW's solution for the front pilots of its Alamosa based standard gauge diesel switchers: Baldwin VO660 #73, Alco S2s #101, 110 and 111, and lastly EMD SW1200 #131. A stationary cast steel three-position coupler pocket was then used on the rear (or "B") end of these same locomotives, save for the SW1200 (note the photo of the Alco S2 at right below). Even narrow gauge side-rod diesel #50 was equipped with two of these devices (right), but has since lost both air cylinders during preservation. Also, it is not clear whether the #50 was ever used for dual gauge switching chores, having spent most of its D&RGW working life in the narrow gauge yard at Durango.

٭ Three-Position Cast Steel Coupler Pocket: The D&RGW equipped both ends of standard gauge GE 44 Tonner #38, the tender of narrow gauge K-37 #494 (now residing as a static exhibit in Antonito, CO), and the "B" ends of the above diesels with the same cast steel, three-position coupler pocket which it used on the dual gauge idler cars below. Two couplers usually equipped each three-position pocket, so that the second, offset coupler could be manually moved to either the left or the right hand position so as to center up with rolling stock of the opposite track gauge from the locomotive. When mounted on a narrow gauge locomotive, such as the tender of #494, the cast steel pocket was simply mounted upside down to allow the outer pockets to reach the higher coupler-center-height level of the standard gauge. These cast steel pockets used removable Sharon brand knuckle couplers with three mounting fingers (above right), were held in place by a single pin, and are really quite heavy; also, no draft gear was provided to lessen the impact of coupling (note the broken knuckles in several of the photos below). Since the D&RGW used full size knuckle couplers on the narrow gauge (unlike some other roads which made use of 3/4 size knuckles), the Sharon knuckles were all interchangeable.

    ٭ Dual Gauge Idler Car: The D&RGW's other solution to dual gauge operations was to mount these same three-position coupler pockets onto specially built standard gauge "idler cars" which could couple up to either standard gauge or narrow gauge rolling stock . . . and then run them in mixed gauge trains (right)! These mixed gauge trains were run mainly between between Alamosa and Antonito, Colorado; and until the last years of steam operations during the 1960s, were powered by narrow gauge K class mikes. In those later years, standard gauge diesels took over from the mikes; and mixed gauge trains effectively ceased, leaving the K class mikes to haul exclusively narrow gauge trains, often of up to 70 cars, out of Alamosa and past Antonito onto narrow gauge rails. For stunning pictures of these operations, see John West's excellent site Narrow Gauge Memories.

The dual gauge idler cars appear to have been built from the frames of scrapped steam locomotive tenders. No two are exactly alike, though each ride on the same variety of 1898 patent Andrews 40 ton friction bearing truck. The three-position cast steel coupler pocket, which usually holds two removable short shank Sharon brand knuckle couplers, aligns with standard gauge rolling stock in the center position and narrow gauge rolling stock in the lower left and lower right positions. Again, no provision for draft gear was made; and since these cars were not in interchange service (obviously), they remained equipped with K-brakes until the end of dual gauge operations. In use these peculiar cars carried no freight, and should be distinguished from the more familiar variety of narrow gauge "idler" flat used by the D&RGW during the 1950s Colorado gas well boom, the latter cars acting as "spacers" between narrow gauge gondolas which actually bore the weight of oversize lengths of pipe.

Two cars have survived, one at the Cumbres & Toltec Scenic Railroad at their Antonito terminus--right next to the two remaining D&RGW 40' Fowler clone boxcars (which were last in use at Alamosa as "stores cars," hence their unlikely survival)--and the other at the Colorado Railroad Museum outside of Denver at Golden. Apparently the Colorado Railroad Museum still gets some use from its idler car, at least from time to time (note turntable pic above).

Idler Car #010793 at the Cumbres & Toltec Scenic Railroad in Antonito, CO. 
(Photos by Barry Bogs & Rick Blanchard)

Idler Car X-3050 at the Colorado Railroad Museum in Golden, CO.
(Photos by Kevin Strong)

Modeling a Rolling Stock Oddity

My friend Barry Bogs first introduced me to the D&RGW idler cars on his Gauge 3 layout: "What's that," I asked. "Oh, that's an idler car, David." "You made that up, didn't you? Pretty neat, just the same," says I. "No, they really did exist. The D&RGW had several of them. There's one up at Antonito. They used to run them on dual gauge trains." So with my initial incredulity satisfied by a handful of prototype pictures, I was convinced this was not the work of Mr. Bogs fertile imagination, but rather what could be a very useful, prototypically faithful, car to have around for dual gauge operations. But how to build one, maybe several?

Barry had not used any drawings for his car--since to this day no detailed prototype drawing for any of the dual gauge idler cars has ever been found, save for a very basic diagram (at right); and so it was up to me to develop my own. Here I have had the help of two very talented modelers and authors in their own right--Mr. Rick Blanchard and Mr. Kevin Strong--both of whom very kindly measured, photographed, and re-measured both existent cars--and in so doing found just how different these cars really are from one another. Indeed no two cars have exactly the same dimensions, though both did the same basic job. The CAD drawings at right are the first result of their research, having been drawn up by me during 2005-2006. These particular ones will go through one more round of revisions before publication, since the three-position coupler pocket drawing owes more to Theo Berlyn's work on his Fn3 K-37 than it does to my friend's research.

40 Ton 1898 Patent Andrews Trucks

The first tangible evidence of a real project has been the production of rapid prototype based investment cast brass truck patterns. To the best of my knowledge, though there have been O and HO scale models of these cars, no one else hitherto has made exact scale patterns of these early Andrews style trucks with the strap locations and raised lettering which make them distinctive to the D&RGW. It's been something of a labor of love, since part of the goal has been not simply to get the sideframes right, but also the truck bolster, body bolster & brake rigging too!

Each component was first measured and photographed by my friends Rick and Kevin, drawn by me in AutoCAD 2002, checked again on site, and then the 2D CAD files were sent to a very talented Swiss model-maker, Mr. Steve Weber, who converted them into 3D CAD drawings using Siemens' Solid Edge software. Steve, who is himself an accomplished builder of museum quality Swiss and German prototype trains in Gauge 3, sent me 3D CAD files to proof electronically, and then the checked files were "printed" in 3D using a Solidscape T612 wax rapid prototype (RP) machine. The wax RP machine sprays a layer of wax several thousandths of an inch deep with each pass of its nozzle to build up a part gradually. Once the red supporting structure, which is made from a different variety of wax that melts at a lower temperature than that of the actual part, is removed in a beaker of warm kerosene, the blue wax prototype is dried and is ready for shipment to the customer or an investment caster. Though the waxes are somewhat fragile (and when breakage does occur during shipping, it can often be repaired with a bit of CA), the results are just phenomenal! Note even the raised lettering on the journal box lids below:

Once the wax rapid prototypes were returned to me, and I sent them to Mr. Dennis Mashburn (K & D Castings) in Abilene, TX, who is himself an O scale model railroader. Dennis operates a backyard foundry where he manufactures investment castings in brass or white bronze for several other individuals as well as garage manufacturers. Dennis burned out the wax RP side frame (above) to make the first generation brass casting pattern of this side frame, from which a subsequent rubber mold could be vulcanized in order to generate additional wax patterns for further brass copies. Alternately, the same first generation brass casting pattern could be vulcanized in a similar vulcanizing process in order to generate traditional spin cast white metal copies. In the upcoming months, I will be exploring both options, particularly with respect to cost.   

The First Semi-Kit

In August of 2005, I began work on an initial one-off model of the X-3050 for my English friend John Masters. Basically, I provided John with two brass body bolsters, end sills, and coupler pocket mounting plates, all of which were cut on my Japax wire EDM, along with Special Shapes " tall brass channel to duplicate the prototype's 10" center and side sill channels. Theo Berlyn (of Berlyn Locomotive Works) had at this time manufactured a number of extra investment cast 3-way coupler pockets from his Fn3 K-37 project, several of which I included in the semi-kit. Six Accucraft couplers, Hartford air hoses and glad hands, some brass bar stock for forming handrails, my scale drawings, and stained western cedar decking completed this rather Spartan kit. Speaking of the latter, it is my guess that the X-3050 originally had tongue-in-groove boards for its decking rather than its current plywood, hence the western cedar decking. Anyway, there were no trucks available at that time (soon to be rectified), and so the semi-kit looked like this:

More To Come . . . (last update: 10-16-09)

Last update: 16 October 2009

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