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Unfortunately there is a lack of consistency among manufacturers in the heights of rolling stock which not only effects coupler heights but also detracts from the appearance of adjacent pieces, The floors of prototype cars are set at standard heights to match platforms for transition of both freight and passengers. Specialized flat cars are major exceptions. Although the floors may not be visible, the differences are very evident at the lower corners of the cars. The most noticeable are the platforms on older open ended passenger cars. Heights may vary by as much as 12 scale inches. Imagine passengers stumbling over the step while going from car to car. Heavy weight passenger cars should line up at the lower corners and not the roof or eaves, since heights may vary and roof contours may differ. Light weight streamlined cars should line up at the roof and end skirts, if possible. A slight compromise may be necessary by dividing the difference top and bottom. Freight car end sills should line up, if present. Hopper frames and tank car walks should be the same height as other cars of the same type. House cars may have side sills that confuse the issue, but usually a line of rivets below door level indicates floor supports. Dropped poling socket supports are not a reliable indication. Study photos of the prototype to note alignments. Often cars can not be set to the exact prototype heights because of truck swing clearance. Removal of underframe detail may be required to allow for oversized flanges. An example is mixing brands of open platform passenger cars. Select the most difficult car(s) to change and use it as reference to alter others. Station platform height can be adjusted to match. The absolute height is difficult to eye-ball. The problem is how much to raise or lower each car. The reference height must be measured from the rail top. Several methods are available. For rough measurements SCALES OR RULES can be eyeballed . More accuracy can be obtained with CALIPERS, if they fit. More often they do not. Some may include depth gauges. Lack of perpendicular alignment will effect accuracy. A very SIMPLE HEIGHT OR HOLE DEPTH GAUGE simple height or hole depth gauge can be made from a 1/16" rod and a model airplane wheel collet. The collet is placed on the surface and the wire is extended to the reference surface or hole bottom. The collet is locked and the length of the wire is measured with a caliper or scale. A more convenient solution is to use a drafting pencil with the lead replaced by a metal rod in the same manner. These can be used with a section of track with a styrene spacer sanded to rail top level as used with parallel blocks below.. A kADEE HO COUPLER HEIGHT GAUGE can be easily modified to handle a set of feeler gauges by tapping the open hole 6-32 to mount a screw to hold 1/8" wide feeler blades, drilled with a clearance hole at one end to fasten on top of the rear of the gauge. Various thicknesses can be stacked to attain almost any height. The blades can be made from Evergreen styrene or K & S brass strips. Fabrication is very easy and may be applied to other scales by drilling an appropriate hole for a screw. The height gauge may also be used to determine coupler pad height for selecting couplers or shims. Since the top of the gauge is slightly under the top mounting height of a #5 box at 29/64" = .453" = 39.47 HO inches, lower heights can not be determined. But an additional gauge could be derived using a low track gauge or MLR tool as a base. A #711 OLD TIME COUPLER HEIGHT GAUGE may be made by modifying a standard one by milling or filing the mounting base to the lower height required. A more expensive and flexible method it to use MACHINISTS ADJUSTABLE PARALLELS on a styrene spacer sanded to rail top level. For most heights a MACHINISTS SURFACE GAUGE AND PLATE can be used. Either the straight or curved end of the scriber like arm can be set to any height to check and level such things as loco running boards and boilers or even cars. Using it as a scriber horizontal lines can be marked. Only one problem exists. To be used with rolling stock, flange-ways should be milled into the surface plate to allow wheel treads to sit on the surface. Otherwise flange depths must be measured and deducted from any height measurements. A more expensive and PRECISE HEIGHT GAUGE can be made from a caliper mounted vertically on a base with an extended feeler. Coming! BACK TO COUPLERS 19th CENTURY BACK TO COUPLER MOUNTING AIDS BACK TO COUPLERS BACK TO MEASURING |
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