Fitchburg Northern--Part I
Building the Tender
by Harry Hungate
Updated: May 12, 2020
In 2010 I started studying up on this long-planned project by purchasing copies of Joseph Foster Nelson’s So You Want to Build a Live Steam Locomotive, Kozo Hiraoka’s The Pennsylvania A3 Switcher and Frank Marlow’s Machine Shop Essentials and Machine Shop Know-How. Hours pleasantly spent surfing the internet brought “Discover Live Steam.com”, Live Steam and Outdoor Railroading magazine, the Yahoo.com Fitchburg Northern discussion group (now groups.io), and lastly Allenmodels.com. I have the greatest respect for Kozo Hiraoka and his absolutely priceless “how to” books on building live steam locomotives. The A3 switcher really caught my eye, but I had my heart set on a loco with six driving wheels, not just four. As I was born and raised in southeastern Louisiana, just north of the sugar cane plantations, the narrow gauge steam locomotives, used to carry the freshly cut sugar cane from the fields to the crushing mills, still in operation in my younger years, have always been of great interest.
The nearest live steam railway club to Jacksonville, FL, where we now live, is the Northeast Florida Live Steamers and Railroaders, Inc., now located on the grounds of the Florida Agricultural Museum, an hour’s drive south down I-95, west of Palm Coast. The club now has around 2,600 feet of track laid and encouraging progress on building what will eventually become over eight thousand feet of 7.5 inch gauge track plus an elevated G gauge railway.
Shortly after we settled in Jacksonville I decided that the Allen Models Fitchburg Northern 2-6-0, propane-fired, in 7.5 inch gauge would fully satisfy my requirements. This locomotive is 1/5 scale, that is 2 1/2 inches to the foot. It is a narrow gauge locomotive designed to run on 7.5 inch gauge tracks.
Allen Models castings for tender arch bar trucks.
This is not a how-to article on building a live steam locomotive, but rather a narrative on the challenges and indeed joys in recovering old skills and developing new skills in metal working and to some extent, wood working and then witnessing the many parts come together in forming an actual working steam locomotive. I followed good advice in beginning this project with the tender, rather than the locomotive itself. The tender requires careful attention to detail and considerable machining, but not nearly so critical and complex as the locomotive.
Thanksgiving weekend 2013 I started work on the running gear for the tender of the Fitchburg Northern. My order for arch bars, journal boxes, bolster ends, bolsters, wheel castings, and a full set of 32 blueprints had arrived a few days prior. My first task was to file the journal box lids and mating surfaces flat and to trim the lids and matching “nibs” to fit. I used super glue to hold the lids in place while I drilled the 1/16 inch holes for the hinge pins (1/16 inch diameter cotter pins). A heat gun applied to the journal boxes released the super glue after drilling. In retrospect, I should have first machined the journal boxes before drilling the lids, so I would not have to keep track of what lid fit what journal box. Hindsight continues to be a helpful feature in this project.
Jounal box (one of eight) with a 1/16 inch drill bit.
I am not a professional machinist. One semester of machine shop practices in the early 1970’s provided at least an idea of the various machine tools and what they might be able to accomplish in skilled hands. Our retirement community provides a fully equipped wood and metal shop. A partial inventory includes an EMCO Maximat 7 lathe/mill with many accessories including collets, a Myford ML-7 lathe with numerous accessories, drill presses, power hacksaw, grinders, etc. I soon acquired a used Chinese 9x20 lathe and set about beefing it up with a four bolt tool post mount and a variable speed drive and digital tachometer. A larger independent four jaw chuck allowed me to machine the tender and locomotive wheels.
Using a dial indicator to establish the rough wheel casting exactly on center prior to machining.
Machining cast iron is not difficult, but it creates an awful mess—airborne carbon and iron dust goes everywhere (including our brand new Toyota RAV-4). I quickly learned to fasten a shop vac hose to the tool post to collect most of the swarf and to always wear a dust mask. My first attempt at machining a tender wheel (the first of eight needed) turned out to be nearly perfect—dimensions well within tolerances. I was so proud of my work that I called my wife, Jane, to come and share in my success. As she entered my workshop I noticed that I had machined the wheel flange on the rounded spoke side (the front side) rather than the flat side of the wheel. After a cooling down period (me, not the wheel) I machined off the flange and re-cut it on the back side of the wheel and finished the wheel for practice. Proverbs 16:18 comes to mind: “Pride goes before destruction, and a haughty spirit before a fall.” Three other castings were discarded before I had the eight wheels required.
Soon after I started this project an older fellow advised me that before I started cutting good metal, I should make two boxes—one big box and one much smaller box. He further advised that all the crap that I would make would go into the big box and if I ever made anything good (useable) I could put it in the small box. I never did get around to making the boxes, but his predictions as to scrap ratio were very accurate.
I soon learned how to make bending jigs for the arch bar truck frames, and how to anneal the C-1018 cold-rolled steel to prevent it from fracturing when bent, but not before I had ruined several pieces of bar stock. Another valuable lesson learned was to write down the various steps in constructing a part. I purchased a large spiral bound notebook, taped copied sections of the blueprints to the left side and on the right side taped the instructions. These included the order in which the steps should occur, complete with dimensions, drill and tap sizes, bolt sizes, and finish (bare, prime and paint, etc.) After completion of a part I usually went back and revised and refined my notes to profit from what I learned while it was still fresh in my mind.
The two arch bar trucks were completed per the blueprints with the exception of the brakes, as I did not care for the non-prototypical brake system as designed by Tom Rhodes, the designer of the locomotive. I consulted The Pennsylvania A3 Switcher and scaled Kozo’s equalized brake design to suit my trucks. It was considerably more work, but I was very pleased with the results and it did wonders to boost my confidence.
With the brakes completed it was time to prime and paint. The trucks were dismantled, degreased, primed and painted. I had to wait for a windless day and hope that not many bugs were attracted to my freshly sprayed paint. Rattle-can Rustoleum primer and gloss black topcoat did a very credible job. Many months later we developed a spray booth in our community workshop which greatly improved the quality of the paint jobs.
Next was the frame for the tender. Castings for the end sills were machined to dimension and channel iron was cut and drilled for the “joists”. A generous neighbor gifted a large plank of red oak left over from her kitchen remodeling project, and I edge-glued the pieces to form the deck for the tender.
Several large sheets of aluminum were ordered, and I took them down to the local sheet metal and roofing company where the incredulous owner listened to the description of my project, viewed the blueprints and then agreed to cut and bend the metal for a very nominal sum. This was a good move as it saved me many hours of hacksawing and filing to obtain tight joints.
The sheet aluminum tank was assembled on the tender deck. The cylindrical tank is an air reservoir for the brakes.
Our community workshop has a small metal forming rolls/shear/brake which I used to roll the back corners and semi-circular dry legs or “noses” on the tender legs. A pair of hardwood semi-circles in each leg maintain the shape. I made a drilling jig from a piece of bar stock to locate the rivet holes evenly. Drive screws serve as rivets to hold the various parts together. I used a large block of lead as a “bucking bar” to set the drive screws. This was a lot easier than trying to get a rivet set aligned with a drive screw that was out of sight in the tank interior. I applied a marine sealant to all of the joints before joining them to ensure a water-tight seal. A follow-up coat of sealant over the backs of the drive screws will eliminate any weeping.
Several hours of tedious hacksawing yielded the several feet of slit brass tubing for the flare board trim.
The curved transition pieces between the tops of the back end and sides of the flare boards required that I turn a set of dies from hard maple. Squeezing the annealed brass stock with a vise formed the pieces to perfection. The rounded edges on the tender top flare boards are brass tubing that I slit with a hack saw blade. A pair of hard maple blocks held the tubing and the saw blade to make a straight cut. I annealed the brass tube and easily bent it around the curves. Soft solder holds all of the brass pieces together. I applied Dura-lac to all dissimilar metal joints to prevent corrosion. Rustoleum rattle can primer and Hunter Green topcoat completed the finish of the tank. The round cylinder at the back of the tender tank is an air reservoir for the air brakes.
The manual feed pump kit arrived, and I machined it with the help of a face plate and angle block on my lathe. I had a difficult time boring the pump as I did not have a sufficiently long boring bar. Lesson learned: obtain the necessary tools rather than trying to “make do”. Reaming and lapping finally smoothed the bore.
The boiler feed water pump is visible in this photo. The pump handle extends out of the top of the tool box.
An automobile distributor vacuum advance unit fitted into the left leg of the tender powers the brakes. After correctly adjusting the brake linkages I can lock all eight wheels easily with lung power on the tube to the vacuum advance. In actual operation, vacuum will be created by a steam ejector under the locomotive cab.
The two toolboxes on the tender top are scraps of black walnut finished with satin polyurethane. Certainly not prototypical, but they sure are pretty! The toolboxes have no bottoms, but open into the legs for access to the feed pump on the right and to the brake cylinder and light switches on the left leg. I will probably make the locomotive cab from black walnut, also.
The headlight (or is it taillight?) for the tender is my design, and turned from aluminum and brass from my scrap box (remember large and small boxes?). Our local jewelry repair man gave me a handful of broken watches from which I selected the lens for the light. An LED provides the illumination. The number 44 is the year of my birth.
I followed the blueprints in constructing the side or classification lights from copper tubing fittings and scrap brass. LEDs and purchased lenses completed the project.
Wiring junction boxes were turned from scrap brass and small brass tubing was used as wiring conduits for the lights. Excellent small gauge wiring was scavenged from an old computer cable. A small battery pack in left tender leg powers the tender lights. I have since cleaned up the wiring and run small brass tubing as wiring conduits.
The tender is connected to the loco via a steel drawbar. On the rear of the tender is a bronze automatic coupler, machined from an Allen Models casting. It required some careful milling and drilling and a lot of hand filing to get it to work smoothly. I completed the coupler for the front of the locomotive at the same time. A polished brass band around the tender deck adds a bit of class.
Automatic coupler and safety chain shackles.
October 2016: The tender is being loaded into our RAV-4 for its first trial run at the West Tokoi & Bostwick Railroad.
This completes the tender build. Please see Part II for the locomotive portion of this build.
It is now May 2020 and the locomotive boiler is ready for pressure testing prior to installation. The feed water pump on the tender will be used to fill the boiler and to pressurize it up to 180 psig. The tender has been quietly sitting in my workshop since it was completed in 2016. Well, not really completed, as I still have to install the brake lines and connections, rinse the water tank, seal the top of the tank, and connect the water hoses to the pump inlet and outlet connections. More photos and text to follow.