Re: Silverton Northern #100

It sure would be interesting to know if the #283 still had an original Baldwin boiler. With good water and good care the boiler could have lasted that long. The 145 lb boiler pressure would have been common for an 1880s steel boiler, like the later C-17s. Perhaps those first Baldwin class 60s with the steel boilers were carrying that pressure also. The Baldwin specs. from that period don't show a boiler pressure or tractive effort, so it is hard to tell. The class 56 and 60 locomotive with the wrought iron boilers were built with steel fireboxes. The wagon top class 56 and 60 locomotive only had wrought iron boiler sheets 3/8" thick. The straight boilered class 56 and 60 locomotives had 7/16" boiler sheets and the steel boilers on #41 and 42 were 3/8" thick. 3/8" steel would definitely be a lower pressure boiler. #22, the wagon top class 60 had a boiler diameter of 48" instead of the 50" on the other class 60s. Wagon top class 56s, #24, 25, 30, 31, & 32 had 46" diameter boilers compared to 48" on the straight boilered class 56s. The frames on the class 56 and 60 locomotives were pretty much the same except for the cylinders.
Dave