Re: nbw sizes

Sizes change based on application, builder, and time... Early cars had smaller bolts and washers.

The washers used were cast gray iron (rather than the later malable iron). Finally, to make things more complicated for a given diameter of bolt, there are two standard head sizes, "regular" and "heavy".

With the above in mind, in the far west we find...
for 5/8 bolts, washer is 2 5/8 diameter (common bolt size on a Carter Car)
for 3/4 bolts, washer is 3 diameter (THE common bolt size on a WSLC Car)
for 7/8 bolts, washer is 3 1/2 diameter (common bolt size on a Carter Car)
for 1 1/4 bolts, washer is 6 diameter (common truss rod size on a Carter Car or other western car)
for 1 1/2 bolts, washer is 7 diameter (Truss rods on later, heavier cars)

Note that the Carters (an Hammond, and occsionally Holman) used eliptical cast washers for the truss rods and lateral truss rods. Holman had a rectangular truss rod washer he used, later used on WSLC.

Randy Hees
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