Kitbashing The Aster (LGB) Frank S.
Text and photos by Frank Krutzke

Reprinted by permission from Steam in the Garden Issue #59

Huatolla Lumber and Mining Company's first locomotive...

Seventeen years ago I took an early 1920's era Bing locomotive to one of the first steamups hosted by Marc Horowitz and Sidestreet Bannerworks. This steamup was held in Denver, Colorado at the Apolo Crane Service's warehouse.. Most of the attendees present were running locomotives of the Mamod variety; very nice running toys, but not much to look at. My model engineering experience is by way of larger gauge live steam and museum caliber replicas, where scale and detail are very important considerations. This background, together with limited exposure to garden railroading and the possibilities of "steam in the garden", resulted in my interests remaining with 7.1/2" gauge live steam. Over the years, I saw various advertisements in model magazines for G scale engines by Pierce, Roundhouse and others. The locomotives in these ads looked attractive, but again, I payed little attention; perceiving LGB style layouts in a basement or garage as not very appealing.

All this changed in September of 2000, when, by way of the internet, I came across a live steam site that prompted me to contact Gale Graham in Albuquerque, New Mexico. Gale is a machinist of the first order, and produces a line of small, live steam engines, mostly stationary in nature. What I saw on the internet was a Shay locomotive for use with one of his stationary designs produced as a Shay engine for this purpose. I called Gale about his engines and he mentioned he was going be in Denver for a steamup at the Colorado Railroad Museum.

Wanting to meet Gale, in October of 2000 my wife and I attended this steamup. Arriving at the Museum, we were surprised to find this gathering, like that of 17 years earlier, also hosted by Marc and Barbara Horowitz and their Sidestreet Bannerworks. This, then, was our second introduction to garden scale live steam. (See the Sidestreet Bannerworks website for photo coverage, www.sidestreetbannerworks.com)

What a change has come over live steam, garden scale railroading in 17 years. The layouts, locomotives and rolling stock now rival some of the best of the larger gauges. One look at Dick Schafer's Galena Railway & Navigation 2-6-2, Alan Olson's Acoma No. 8 or Jim Hadden's C&S Mogul pushing his live steam rotary snowplow and I was hooked.

My wife and I were instantly in agreement that here was a new hobby we could share. Since it was winter time and the weather not conducive to gardening, we made the decision to begin with accumulating locomotives and rolling stock.

Over the years we have both shared an interest in railroads that served the timber and mining industries of Colorado, the Pacific coast and the California woods. With this interest in mind, we agreed that a simulated logging/mining railroad would be our focus.

Asking questions of those in attendance quickly led to my realizing that very little is available commercially in the way of American style, live steam logging locomotives. Most live steam, garden scale engines are modeled after European locomotives, which have a distinctly different appearance from their American brethren.

Having considerable experience in model engineering, I realized that the quickest way to an American logging locomotive would be to kitbash an existing commercial product. I talked with Alan Olson at the steamup about how he modified a Roundhouse Engineering Lady Anne to obtain his Acoma No. 8, but still was undecided the exact route I would take. A call to Alan the following week provided additional wealths of information on the hobby and what was available to kitbash.

He also led me to the website of Steam in The Garden Online (www.steamup.com), where I saw some pictures of other kitbashings and scratchbuildings. Contained on this webpage were photographs of a logging style tank locomotive by Jim Hadden. Having seen Jim's rotary snowplow at the steamup, as well as his scratchbuilt Heisler, I called Alan back. I learned from Alan that Jim, who is from Park City, Utah, is a very experienced kitbasher. Jim has commercially converted a series of the Aster Frank S. locomotives into a logging tank locomotive, which he calls Frank the Tank. This made the direction to take an easy decision, since I had seen a standard Frank S. run at the steamup, and was very impressed with the performance.

A quick internet search for 'Aster Frank S' and I found a used locomotive for sale at the right price. I immediately contacted Jim to ask if he would object to my being a copycat, and was delighted to hear that he would be more than pleased to help out. A day or two later the mail arrived from Jim with some drawings, basic dimensions and a list of materials and detail parts he had used in his conversions.

A quick trip to Caboose Hobbies in Denver, to raid the Trackside Details™ display and buy sheet brass, and I was off and running. All the brass for the tank, cab, running boards, etc. is 6 X 12 inch sheet in .032 and .040 thickness, manufactured by Special Shapes Company. The remaining brass is K&S brand. I also purchased several 1/2 and 3/4 inch copper pipe couplings for the domes and a 1/2 inch pipe cap to make the spark arrestor, and some 3/8 X 3/4 walnut strips for the buffers.

Prior to beginning the conversion of my Frank S. several decisions needed to be made. As mentioned earlier, I find scale and detail important elements of model engineering. The hobby of garden railroading abounds with different scales and a seeming indifference to intermixing these scales. Most prototype logging railroads were built to a gauge of 3 feet, and most garden railroad track is 45 mm gauge (gauge 1). This meant that I would be modeling everything in a scale of 1:20.3.

In my discussions with Jim about what he would change if he did it again, he stated that he felt his engine was a little small to fit with 1:20.3 rolling stock. With this in mind, I decided to scale up his engine approximately 3/4 inch in length, 1/2 inch in height and 7/16 inch in width. This would not only better fit my chosen scale, but would give more room in the cab for radio control equipment.

The second decision was to detail the locomotive as much as possible, given that I was building it up to be run on a track and not sit on a mantel. This led to redesigning lead and trailing trucks to be more prototypical, reworking the steam gauge location and adding a plethora of detail parts. I found myself relatively inexperienced at working with thin sheet brass and very small detail castings. Discussing this with Jim led to my decision to use a resistance soldering tool, in this case one made by P-B-L in Ukiah, California. Resistance soldering tools offer several distinct advantages; not the least of which is, they do not drag a smear of solder around with their tip. They also provide a great deal of control over the heat applied and the ability to localize that heat.

All soldering was done using Stay Bright™ brand silver bearing material and their flux. I have used Stay Bright solder and flux for many years in model engineering. It has good strength, flows easily and the flux is easy to clean up; P-B-L also recommends this product.

The project began with completely disassembling the Frank S. Modification started with the frame, which needed to have small pieces cut off of the front and back. This was done to accommodate a redesigned pilot and an extended cab floor and rear buffer.

Sadly, the Frank S. frame is made of a zinc based alloy, and will not take to soldering; this necessitated that all additions be screwed on. When stripping the Frank S. down, there were enough left over screws to accomplish the attachment of all the added parts. The screws Aster uses are 2mm for the most part, and I used a tap obtained from Caboose Hobbies to cut threads, where needed, for these screws. There are also several small parts spot-welded onto the Frank S. that I removed to save for later use in the conversion. These included the cab steps, reversing lever detent bracket and the hangers for the valve gear lifting rod located behind the Walschaerts link. They were removed by using a small screwdriver to break the spot-weld.

The boiler wrapper also has several small holes in the smokebox area where the air pump is attached. I filled these holes with scraps of brass sheet and silver solder. Hard solder needs to be used for this because a lead or tin based solder might melt with the heat of the smokebox.

I also turned down the decorative radiuses on the smokestack, and replaced the Frank S. safety valve with an Aster valve as used on the American Mogul.. The tender wheels were removed and set aside to use as the lead and trailing truck wheels. The steam gauge on top of the functioning steam dome in the cab was removed and an adapter was fabricated to mount a relocated gauge using a syphon tube. The gauge and syphon tube were obtained from Jerry Hyde at Hydeout Locomotive Works. Relocating the gauge now places it in a cab window for better visibility.

The existing Aster butane tank was next on the list. It needs to have the outlet/control valve face towards the center of the tank so that the tank can be moved into the coal bunker. This was done by first removing the fill valve and the gas control valve stem to protect them from heat damage. I then liberally coated the silver soldered gas outlet tube joint with borax flux prior to applying heat to liquify the joint and turned the outlet tube 180 degrees.

Work then commenced on the new cab, saddle tank, frame extensions and buffers. The layout of dimensions on the brass was lightly done using a scribe to mark the inside, or some other nonvisible portions of the sheet. Scribe marks need to be made with a sharp scribe so that the surface has a single, well defined line. Lines need to be on the inside surfaces if possible, as they can be hard to remove on visible areas prior to painting. If you need to mark outside surfaces, the brass can be coated with layout bluing. This allows scribing a light mark into the bluing which reduces the damage and distortion of the metal surface.

The cutting of all exterior edges was accomplished on a sheet metal shear, while the cab roof and the inner and outer tank wrappers had their curves formed on a set of sheet metal rolls. I have these tools in my shop, but for those who do not, most sheet metal shops will provide assistance by doing this for a nominal charge.

All cutouts for the windows and doors, etc. were made using a hand nibbler. I also cut out matching window frames to be soldered on the inside of the cab around the windows. These had a narrow edge that would have been almost impossible to cut without the nibbler. Nibblers are inexpensively available from Radio Shack™ and most tool specialists, and will easily cut .032 to ..040 brass sheet. The use of a nibbler allows you to cut to within several thousandths of an inch of your line and then clean up the cut with only a pass or two of a file.

To start the nibbler in a window, a hole is needed; I used a sheet metal hole punch, manufactured by Roper Whitney Co., but could just as easily have drilled the hole. The advantage to punches and the nibbler is that they cut clean, accurate holes and do not distort the sheet. The cutting of all the windows and doors in a given sheet took only 15 minutes or so, and a like amount of time was needed to clean up the cut to the lines. The best way to clean up the cutout in an item is to hold the piece in a two screw wooden clamp, like those available at Home Depot, Lowes or other building supply stores. Place the edge to be cleaned out as close to the nose of the clamp as possible and use a fine cut file; two or three passes with the file and it is done.

Soldering all of these pieces together came next. At this point the wooden clamps became very handy. They are ideal for holding pieces square to your work table and clamping them in alignment; freeing both hands for the soldering task.

I found that the best way to use the resistance tool was to heat the backside of the joint. I did this in several places while applying very small amounts of the solder to the front side of the joint to tack the pieces together.

When the joint was fully tacked, I then came back, still heating the backside, and filled in the joint between tacks. It is also possible to move the resistance tool down the joint and feed in the solder ahead of the tool, all from the same side. This method, for me, did not leave as nice a joint as heating the backside and feeding the solder in from the front. One caution in the use of the resistance tool is to keep the tool in firm contact with the brass sheet. Without firm contact, the tool will create an electrical arc and blemish the brass surface. Also, when soldering small parts, attempt to apply all heat to the larger brass surface. This sinks the excess heat and protects the detail part from being melted.

Most of this soldering work was accomplished in three or four long evenings.. When the structure was complete, I applied the detail parts. The roof vent, air compressor, generator, head and backup light, coal bunker handrails, boiler steps, etc. are all brass castings from Trackside Details™. Cab door hand rails, coupler release rods, pipes and tank handrails are brass wire soldered in drilled holes or glued into stanchions. The window and door awnings are fabricated items. The domes were also fabricated using Trackside Details dome tops and copper pipe couplings in 3/4 and 1/2 inch sizes, and are soldered to the tank.

The rear steam dome has a tube that passes through the dome and tank to allow the boiler safety valve to vent to the outside. Also, the tank has similar pass throughs for the boiler fill tube and the tank hold down screw.. These pass throughs are necessary because the tank is designed to hold water, and an axle pump, for boiler feed, will be fitted at a later date. All of the detail items and domes were also soldered on using the resistance soldering tool. I found that for most small detail items, the best technique is to tin the item and the attachment point and then hold the item in place with tweezers. While holding the item in place, heat the area as close to the attachment point as possible with the resistance tool until the solder melts.

Fabricating the lead and trailing trucks came next. This was done using the existing Aster tender wheel sets and 1/16 thick K&S brass stock. The trucks are fully sprung off of center bolster pins, which are 6-32 brass machine bolts. These bolts have their head soldered to the bottom of the locomotive front buffer frame and cab floor. This pin rides in a radial slot in the top of the truck bolster, with a spring and washer between the bolster and frame. The trucks pivot on similar pins which attach to brackets screwed to the cab floor and soldered to the steam supply manifold between the cylinders. The trucks, being sprung, provide a significant download on their wheels, which ensures that they will track properly.

When it came time for assembly, it was necessary to replace some of the insulation between the boiler and the jacket. This was done using ceramic fiberfax obtained from a ceramics supply store that has repair parts for kilns. The balance of the parts went together without problems.

The tank is held on to the boiler by the fill tube cap, in this case a Goodall-type valve, and a 3mm bolt silver soldered to the bell bracket. The saddle tank fill tube pass through is a close fit on, and slightly longer (approximately 1/64 inch) than the fill tube, and the cap and washer press on the tube when they are snugged up tight.

The displacement lubricator I relocated to the pilot using the existing plumbing. As a point of caution, the lubricator tubing is very small diameter copper and should be annealed before bending to its new path. Small diameter copper tubing has a tendency to work harden in use, and while being un-bent the tubing wall can kink .

The reversing rod, underneath the frame, also needed to be shortened and its actuating arm bent forward to allow space for the trailing truck pivot. The throttle knob I modified by removing the bakelite to reveal the brass bushing, which was then soldered to a brass lever that can be reached through the cab door.

The gas valve was also similarly modified, but in this case, instead of a lever, an Ozark Miniatures™ barrel was epoxied onto the brass bushing. This barrel sticks up through a hole in the coal bunker, and appears to be a drinking water barrel riding on top of the bunker. At a later date radio control servos will be installed to actuate the throttle and reverse lever.

When all items had been fitted and the mechanical operation and clearances had been checked out, the locomotive was disassembled for painting. The few small areas having solder runs were scraped using the back edge of an X-acto™ knife. Corners that needed to be cleaned out were scraped using small jewelers screwdrivers. Sharp, square cornered scrapers will remove the solder without cutting into and marring the surface of the brass. Further surface preparation was accomplished by sanding all the areas to be painted using foamboard fingernail files obtained at Walgreens. I found that the black emery kind performed the best. Brass does not take paint well, and needs to be thoroughly scuffed up prior to applying the primer. It also needs to be scrupulously cleaned. Everything was washed with soap and water and completely rinsed. After washing, because oil from the skin will re-impregnate the brass, all handling was done using paper towels or clean rags. Prior to spraying, the surfaces were again wiped down with Acryli-Clean to further insure an oil free surface.

I did all painting using spray cans of Krylon Epoxy Satin Enamel over a prime coat of Krylon Epoxy Grey Primer. I have also used Zynolite brand epoxy paints; either are excellent products and easy to apply. Epoxy paints have good adhesion and hold up well against chipping. They are also less likely to run when applied. For trim and touch up I sprayed some of the paint into a small cup or a shot glass and let stand for 30 minutes to thicken up. I then used a small brush to apply it to the needed areas. The smokebox and stack were painted with Scalecoat graphite and oil paint. After I finished painting, the final detail items (builder plates and number plate) were applied to the smokebox front and the sides of the smokebox using J-B Weld epoxy. This epoxy, which is very strong, is rated for 600 degrees and will easily hold up to the heat of the smokebox. J-B Weld epoxy is also available in a Quick style 5-Minute formula, which is not capable of withstanding as much heat, but has similar strength properties.

After all the painted items were dry, the locomotive was reassembled and the balance of the detail items added. Wood was epoxied to the front of the buffers and link and pin coupler pockets applied. The front and rear steps were fabricated and bolted on and poling pockets glued in place. The couplers were then fitted; together with coupler release rods. The couplers are modified Accucraft™ products. The shanks were shortened to fit the Trackside Details link and pin coupler pockets and drilled to accept the link pin. The ends of the knuckles are also drilled vertically for a link pin and a slot cut in them to accommodate the link.

The coal in the bunker is simulated using real coal bought at Caboose Hobbies. Dams around the cutouts in the bunker top for the butane filler and burner valve, and a dam on the outside edge were made using masking tape. A thin layer of coal, one or two grains thick, was set in place and then thin cyanoacrylate glue applied and set up using Insta-Set. The final layers were then put in place and similarly glued. The coal was finally painted using flat black epoxy enamel to cover any gloss caused by the glue.. Decals for the logo I made using an ink jet printer and Super Cal. I first tried using the clear decal paper, but the printing is not opaque enough to show up well over the underlying green paint. I redid them in a red background using the white decal paper. The numbering is a commercial decal product. All decals are overcoated by airbrush using Poly Scale water based satin overcoat.

The first run took place December 29, 2000, at the Denver Garden Railway track at the Colorado Railroad Museum. The locomotive runs extremely well on straight butane, especially so since the butane tank sits close enough to the boiler to keep warm. The lead and trailing trucks, with their downward spring loading, guide the locomotive very nicely through switches and track irregularities. All that is now lacking is radio control and the axle feed pump drawing water from the tank.

I have been asked several times, "How much time did it take?" Although some time was not logged, most of it was. The project consumed something over 120 hours spaced out over 6 1/2 weeks. A significant amount of this time was spent working out the mechanics of the conversion and the procedures to be used.

Many small items took inordinate amounts of time. For example, fabricating the entire cab took only one evening, while building and attaching the front and rear steps and the coupler release rods took twice as long.

Was it worth it? Only one look at the finished locomotive and you have the answer. Will I kitbash another? Already on the drawing boards are the conversion of 2 Roundhouse Russell locomotives into a tank style Mallet patterned after Weyerhaeuser Timber Co. No 9.

This has been a very rewarding project, which in a short period of time has provided Huajatolla Lumber and Mining Co. with their first locomotive. For those who have thought of live steam kitbashing, but have put it off, I can only say, dig in and enjoy!