US $5.95 • Can $7.95 - O scale trains

Some Thoughts for Scratchbuilderson Finding DimensionsBrian ScacePrototype photos used by permission ofBob’s Photos.Much attention has been devoted to the construction methods,such as soldering brass, working with styrene, wood, Strathmore,et al. That’s, after all, what how-to magazines like ours dofor their worth. We supply a medium through which one personcan explain to another person how something was done.One aspect of this equation remains shrouded in mystery,receives little comment, and deserves more, as has beenbrought to my attention by Marty Iftody’s letter published inIssue #12. He asks how to get the info needed before embarkingon a scratchbuilding project. Here are some thoughts frommy locomotive-building experience.First, if there are drawings, I use ‘em. Many of the historicalsocieties, such as the New York Central System HistoricalSociety, have drawing archives. These groups are worth joiningto get access to these archives. Also, a post on some of theinternet sites, such as Bobber Gibb’s Otrains List [http://groups.yahoo.com/group/otrains], may get you linked up withsomeone who has a drawing you’re looking for in his musty,dusty, files. Lastly, there have been literally thousands of drawingspublished in the model press over the years. Some are notso hot, but many are worthy of use.You need to be careful here, for a couple of reasons. Forlocomotives and rolling stock, some of these drawings can leadyou astray in a big way. When you get that big roll of Limadrawings for a B&A Berk in the mail, you may think you havethe last word in fidelity. T’ain’t necessarily so! Chances arethat the drawing of the complete locomotive is what is calledan “assembly drawing” or a “general arrangement”. Assemblydrawings and general arrangements (for our purposes, assumethat these are one and the same) are used as keys to the other38 • O Scale Trains - Sept/Oct ’04several hundred detail drawings of each individual piece thatmake up the whole. There’s a detail drawing for the pilot casting,another for the cab armrest, and another for the bell, allnumber-keyed to the assembly drawing. Assembly drawingsdon’t have to be all that dimensionally accurate, just goodenough so that you can refer to the individual componentdrawings, and visualize the inter-relationship of the parts. Somecompanies’ assembly drawings are quite accurate, while otherswere notorious. Alco, for example, was noted for form errors intheirs, resulting in some major gaffs in production Diesel models.Even high-end imports are not immune to this, as severalNYC Hudson models have repeatedly erred in firebox shape,yet are faithful to the drawings used. Even the locomotive drawingsin the various editions of The Locomotive Cyclopedia areflawed in this regard, because they are derived from assemblydrawings, so be careful.The next thing to be careful of is the drawing date. Look inthe box under the drawing title for the last revision date. Youneed to be wary of this, especially if you are modeling 1952,and that locomotive of your dreams was built in 1929. Equipmentwas constantly upgraded and modified throughout its servicelife. Just as color schemes on, say, a boxcar changed overtime, brakes were upgraded, safety appliances added, truckswere changed, and a thousand other things were replaced andupgraded. The result is a new detail drawing for that new brakecylinder, and that new drawing number noted on the assemblydrawing as a revision. The whole assembly drawing quite probablywill not be redrawn to reflect the revision, however, andyou need to be aware of that!We can conclude that there is info to be gleaned from thedrawings, but they are not the definitive source we would likethem to be. They are, however, a good addition to our arsenal.With or without drawings, the next step is to find photos.Again, photos are usually pretty easy to find, whether in books,the same historical society where you got the drawing set, or