Page 16 - November December 2013

Bucyrus 250 ton Wrecking Crane in 1/29th scale Peter Prydderch
This is a new departure; a very large model built from styrene of various thicknesses.
Such an American wrecking crane was used for recovering locomotives. The completed model is 29 inches long in travelling mode. The US practice when travelling was to have the jib clear of the boom car (match truck), and held rigid by hawsers tightened by the jib’s elevation.
All that’s needed for the construction are elementary skills, a set of wheels, roller bearings, Kadee couplers, glue/solvent, and a few ball bearings . . . oh, and a couple of hundred rivet heads!
The crane has a working jib, and winding gear. It has movable outriggers, and the body swivels. Provision is made for motors/servos, to have the whole thing operating by radio control.
The kit came as a flat­pack of styrene sheets with the shapes laser­cut. Think of a very large etched brass fret, but in plastic. The designer is a retired engineer who’s worked in Europe, and all holes, etc are metric. This is a quality kit, with excellent illustrated instructions.
Any thicker parts are made by layering, and it works without any problems. This really was a joy to build.
The manufacturer has applied his manufacturing knowledge to the production of this crane, and a couple of other items. See www.thegalline.com, with whom I have no connection. The whole kit has tabs and slots, and thus a good solvent will suffice. A few days were allowed for the joints to cure. But, there’s plenty to assemble/glue in whilst waiting.
Looking back, the rivets – well over a hundred of them (Grandt Line #128) – ought to have been added whilst the sheet was flat. They’re plastic mouldings. Either holes are drilled and the rivets are put in by their tails, or the heads are cut off and placed onto the marked positions. That’s the thing . . . everything’s marked out. Solvent holds them.
First the base/chassis is constructed . . . easy! Then, the outriggers are constructed. These needed sanding to have an interference fit in the housings. Starting again, it would be tempting to make the outriggers first, and see how much leeway the base had to accommodate them.
The containers for the weights were then built, and tested for a fit into the slots under the base. Their attachment was left until later to save the weights becoming cumbersome when working on the base. The weights were supplied to be stuck inside the bases. It was decided to drill and tap these bits of mild steel to mount the trucks (bogies) onto through the container. It worked well.
The boom (jib) was built next, and it just slotted together. The pulleys needed more thought. It was decided to veer from the recommendation and put grooves into the 90 thou discs, with washers between. The suggestion was to have large and small discs alternately, with the thread between the larger ones. It would have worked, but the grooves look better, and more were fitted in. The thick discs were mounted on a bolt, put into a pillar drill, and a file held across the edge as it spun. It was easier than it sounds. Having said that, the stringing process was a nightmare . . . perhaps I used the wrong thread. The Buckeye six­wheel trucks (bogies) are a joy to behold. They consist of three layers, and about a dozen other parts to slot together. When a couple of bits of 2 mm rod are inserted (the instructions forgot to mention them) they become fully equalised. Whilst the wheels recommended are narrow­gauge products – with broad treads and deep flanges – finescale wheels to Slater’s profile were used. Really, if the track is so bad that the equalisation cannot cope, then . . . ! They really are something else. As stated, the guy is an engineer, and it shows.
Whilst the axle holes were designed for the cup bearings supplied, opening the holes a thou meant that Aristocraft ball
races could be pressed in with parallel pliers (or vice jaws). This is a heavy vehicle (about six pounds), and it rolls easily with the ball races.
The word BUCKEYE is burnt in, whereas it should be proud. Slater’s 2 mm upper­case lettering placed on the incisions make a big difference, and the spacing is neatly maintained. That just leaves the body and the winding gear to build; oh, and the turntable.
Nothing to say about the body, really; it just glues/slots together. Removable weights were put into the back to counteract the weight of the boom (jib). The roof was assembled separately, and was left removable for access to the winding gear sub­assembly.
The winding gear comes as a framework to hold the base of the boom (jib), and there are holes for the winding drum shafts and slots for the motors/servos. The decision was made to have the crane in its travelling position, with provision to change its position manually. All shafts were made of Evergreen tubing (225 for all wheels, 227 for winding drums), and the holes were opened up a fraction accordingly. The designer recommends brass tubing.
The shafts were cut to length, and a brass nut was opened out as a clearance fit. A hole (8BA clearance) was then drilled into one of the faces of the nut. This nut was then put onto the shaft within the frame against an inside wall. Its position was marked, and an 8BA tapped hole was put into the hollow shaft. Nothing is taking any strain for a non­operating model. Then, a drum is made from larger tubing, with ends. Once again a clearance hole in the middle of the drum, and a tapped one in the shaft. When reassembled with the drum and the nut inside the walls of the structure, the w/drum can be turned by hand to leave the correct amount of thread in the boom (jib) for the position of the boom/main hook/ ancillary hook. Then a long 8BA bolt can be screwed through the nut into the shaft and it will catch on the floor/support, or anything else added as a restraint. This is repeated for the three winding drums. To change any of the settings the winding drum and bolt/nut are turned back a bit to release the nut from the shaft. Then, the new setting can be adopted, and the bolt screwed back again into the shaft.
The last thing is the mounting of the turntable onto the base/ chassis. The parts go together easily, and an alteration was made to countersink one of the plates to take 5 mm ball bearings. One on the spare rings produced in the laser­cutting process can be used to restrain the balls on the lower plate. Put it all together, and that’s that. The process would be slightly different to motorise it, but not too difficult. Such a version would be useful for a static working model at a show. In fact, it’s crying out to be motorised!
Painting/lettering was done as the construction developed. I’m happy to accept that any difficulties experienced were of my own making.
The kit cost just under $500 delivered to the door. This is a class item, and worth every cent.
For reference material, go to www.aristocraft.com and register (free) with their Forum. Go to the Off­Forum Topic, and using the Search facility for TheGalline will bring forth 250 ton crane in 1/29. This is an extensive thread, and the second page will produce a 30­minute video of the full­size version.
The designer is Alan J Friedland of Great American Locomotion, who is a very helpful sort of guy. You’ll find him on www. thegalline.com.
Beyond that, if you wanted to discuss this project before making such a large monetary commitment, please feel free to contact me.
e­mail: ppltd@btinternet.com
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