What length of turntable is going to be needed for this locomotive?
I was just looking this stuff up last night, in answer to a different question...
K-27 - 58' 10" length, 9' 6" wide (over cylinders), 62" boiler dia,
K-28 - 62' 10" length, 10' 5" wide, 65" boiler dia.
K-36 - 68' 1" length, 10' 5" wide, 72" boiler dia.
K-37 - 65' 3" length (loco nominally the same length, shorter tender), 10' 5" wide, 74" boiler dia.
source - "Rio Grande Narrow Gauge" by John NorwoodSo, for a K-27, you'd need a turntable of at least 53' or so to accommodate the wheelbase, allowing for 3' overhang from the pilot truck and rearmost tender axle. That's about 31.5" long. I'd go longer, just in case a K-36 comes out. 37 or 38" should give you plenty of room for that.
But then Bachmann will bring out the Sumpter Valley articulateds, and...
Later,
K