A 250 TON BUCYRUS-ERIE WRECKING CRANE
BY ROY E. HILL
I HAVE ALWAYS been fascinated by railroad maintenance-of-way equipment and consider a wrecking crane the main component of a work train. So in October of 1992, I decided to build a wrecking crane in 1:22.5 scale. The prototypes ranged in size from a few tons' capacity to the 250 ton derrick. Well, if I was going to build one, why not make it the largest?
Ultimately I found the perfect crane plans in the July 1966 issue of Model Railroader. I enlarged the plans to 1:22.5 scale and was ready to build. But from what material? Brass seemed the logical choice but it was too expensive and too hard to work. Wood seemed out of the question. So I chose styrene because it was light, very strong for its weight, and easy to cut glue, file, tap, and bend. It is also easy to paint. What is more, I was able to find a source of scrap styrene in assorted size and thickness for 50-cents per pound and one pound is a lot of styrene!
Unfortunately, nothing else I needed except couplers, trucks, wheels, and brakewheel was commercially available.
...SO I STARTED
The cab would be first. I decided to build the entire model around it. I first made a balsa and pine form to the inside dimensions of the crane's cab. Then I cut a sheet of plastic somewhat larger than the approximate size of the flattened cab area, put it on the form, placed the assembly in the kitchen oven, and set the temperature to 300 degrees. As the temperature rose, I watched the plastic slowly bend itself over the form. Eventually I removed it and, wearing gloves, finished forming until the plastic cooled.
I made the boom from 1/16-inch thick sheet styrene. First I rubber cemented photocopies of the full size plan onto the plastic, then cut and filed the parts to the inside flange lines. I cut and burred the top and bottom flanges on a 4 inch Dremel table saw. I blocked up the sides, brushed liquid solvent-type plastic cement onto the mating surfaces, and let the assembly dry.
The left- and right-hand basic "H" tapered sections of the boom came out surprisingly well. I then drew locating lines for the many small pieces of the boom and cemented each in place. When I had finished both sides, I put them together and temporarily joined them to the cab.
Next came the 28 pulleys of assorted sizes. I used the plans to determine size and thickness, then lathe-turned a pattern for each size. I made an (expensive) RTV mold for each and poured Cerro-Bend metal into the molds. The results were less than perfect; the parts required a lot of clean up with files. Finally I drilled center holes, primed and painted each piece, and assembled the pulleys into the boom.
The base consists of four large "H" beams. I cut them to size on the Dremel saw. I blocked up the sides to the middle of the flanges, glued the parts together, and cut them to length. I positioned the beams on the plans, added the top frame plates, and beveled the ends of the center plate. The rest of the job involved locating and attaching various sub-assemblies, drilling and installing dozens of rivets, and adding numerous details.
ANYWAY...
By now I must be boring you so I'll just point out some highlights:
Since the plans showed no interior detail, I did a lot of research, examined a lot of photos, and drew my own plans. I cobbled together gears and bases from whatever I could find in the scrapbox. I also researched and detailed the left-hand side of the model from photos of smaller cranes; very few photos of 250 ton cranes exist.
Building the cab interior was a nightmare. I had to make many cuts and add many clearances. Each required guessing and every time I had to add something I had to change something else. It was really frustrating and took patience and fortitude. I attached the cab with four screws, just in case.
If you should try such a project yourself, I can help you avoid one potential error: Avoid cementing in the stack. On the prototype, it was removable so the crane could negotiate low tunnels and bridges.
I searched through five different stores before finding gray nylon line of the proper diameter to represent 3/4-inch diameter cable.
Eventually I discovered a color photo of a Union Pacific crane of the same type as I had built and used that as a painting guide. Unfortunately, my crane was mostly finished when I found that photo so I had to paint the silver "V" stripes on the front and rear of an assembled model. That was one of the most difficult jobs of all!
All in all, the big crane seems to have turned out all right. I guess it was worth the effort.
FEATURES
Construction time approximately 700 hours.
Cost approximately $300.00.
28 pulleys, 3 sizes.
10 doors open and close with lock mechanism.
6 wheel drive with 12 volt d.c. motor, 3 sprocket chains and 6 sprockets on ARISTO-CRAFT heavyweight passenger trucks. Correct Buckeye trucks unavailable.
3 volt geared motor rotates cab 360 degrees left or right.
3 volt geared motor lifts and lowers boom, main hook, and auxiliary hook.
10 outriggers. 5 places move in and out on 32 rollers and pin into frame in five places.
Cab rotates on 8 spring-loaded cast-hollowed rollers.
Cerro-Bend cast pulleys, side steps, rollers, hooks, outrigger jacks.
244 individual rivets.
Operating coupler lift bars.
