Added Strength
CRAFTSMAN/Bob Walker, photos by the author
Timber Pins I build each of my bridges with pins be- tween the ti mbers. This adds a physical as well as chemical bond to each joint.
The story I am about to re- count may or may not be true, so let’s just put it in the “Urban Leg- end” class for now. Suffice it to say, this story illustrates the point I am trying to make this month very well. When On3 was in its infancy in the late 1940s and early 1950s, there was little com- mercial product available. Folks had to improvise, adapt, and overcome (sorry, Ma- rines, for stealing one of your mottos) to build their railroads. Other than the fact there were no loco- motives, cars, structures, or track components then available, modeling three- foot gauge was a breeze if one was a real glutton for punishment that is! The guy in the legend had con- structed a D&RGW K-37 class 2-8-2 much like the prototype had done, start- ing with a standard gauge 2-8-0. He used a Varney
82 RAILROAD MODEL CRAFTSMAN
“super Consolidation,” and to call the thing “heavy” was a gross un- derstatement. I believe the term “lead sled” came from these mod- els. He had done a very credible construction job and had made himself a very believable D&RGW narrow gauge Mikado, to which he had added weight! Now the model took two men and a small boy to put on the track. She was heavy!
It is likely, dear reader, you
know where I’m going with this. Your suspicions are indeed cor- rect. This engine was destined to meet the floor, and it did. Here’s the story, as related in smoky club rooms and dank basements and no doubt embellished over the years: He had made a tres- tle of ¼-inch (scale 12x12) balsa wood, trusting the prototype’s en- gineering and design to make it appropriately strong. Northeast- ern Scale Lumber was not yet in the picture, so the much higher strength basswood was not yet
available in the sizes necessary for this task. On its maiden voy- age, the Mikado crushed that bal- sa wood trestle to virtual splin- ters and made a scale 50-foot plunge to the floor, where it actu- ally took out a chunk of concrete. The crash and the model’s build- er made a noise heard for blocks. Several factors come into play here, forming the perfect storm. He used hydroscopic adhesive, and the basement was humid, thus weakening all the joints. Bal- sa’s nature of being lightweight, soft, and weak is not conducive to trestle construction, where the strength of the model is a real fac- tor. Lastly, none of the joints were pinned or otherwise reinforced. With the already weakened joints, poor choice of materials, and flawed construction methods, the trestle was a disaster waiting to happen. From the way the tale is told, it didn’t wait long. I am told the story had a happy ending: the floor took more dam-
SCRATCHBUILDER’S WORKSHOP
Page 1 |
Page 2 |
Page 3 |
Page 4 |
Page 5 |
Page 6 |
Page 7 |
Page 8 |
Page 9 |
Page 10 |
Page 11 |
Page 12 |
Page 13 |
Page 14 |
Page 15 |
Page 16 |
Page 17 |
Page 18 |
Page 19 |
Page 20 |
Page 21 |
Page 22 |
Page 23 |
Page 24 |
Page 25 |
Page 26 |
Page 27 |
Page 28 |
Page 29 |
Page 30 |
Page 31 |
Page 32 |
Page 33 |
Page 34 |
Page 35 |
Page 36 |
Page 37 |
Page 38 |
Page 39 |
Page 40 |
Page 41 |
Page 42 |
Page 43 |
Page 44 |
Page 45 |
Page 46 |
Page 47 |
Page 48 |
Page 49 |
Page 50 |
Page 51 |
Page 52 |
Page 53 |
Page 54 |
Page 55 |
Page 56 |
Page 57 |
Page 58 |
Page 59 |
Page 60 |
Page 61 |
Page 62 |
Page 63 |
Page 64 |
Page 65 |
Page 66 |
Page 67 |
Page 68 |
Page 69 |
Page 70 |
Page 71 |
Page 72 |
Page 73 |
Page 74 |
Page 75 |
Page 76 |
Page 77 |
Page 78 |
Page 79 |
Page 80 |
Page 81 |
Page 82 |
Page 83 |
Page 84 |
Page 85 |
Page 86 |
Page 87 |
Page 88 |
Page 89 |
Page 90 |
Page 91 |
Page 92 |
Page 93 |
Page 94 |
Page 95 |
Page 96 |
Page 97 |
Page 98 |
Page 99 |
Page 100