I went and did a little research about this locomotive....here is what I found
She was built in 1929, and spent the first 22 years of it's existence working for the Hammond Lumber Company and it's various subsidiaries in Oregon and California. Starting out with the number 6, she was changed to #12 by the Hammond & Little River Railroad in 1931. She was sold by Hammond in 1951 to the Arcata & Mad River Railroad of Blue Lake, CA where she worked until 1956 when #12 was sent to Arizona for the Southwest Lumber Mills. For a while, Southwest ran #12 with a large tank car as an auxiliary tender before adding a normal rectangular tender. After the tender was added, the fuel bunker was removed but the tanks were retained. In 1959 Southwest Lumber Mills became Southwest Forest Industries and #12's water tanks were removed. #12 was retired in 1960 and donated to Coconino County and displayed at the Fairgrounds southwest of town (Fort Tuthill)until the early 90s when #12 was relocated to Flagstaff's Pioneer Museum (just north of Flagstaff on the Grand Canyon Highway).
Specifications:
Wheel Arrangement: 2-6-6-2t
Tank or tender type: Split saddle tank (smaller version)
Build date: 1929
Serial number: 60870
Driver diameter: 44 in.
Boiler pressure: 200 psi
Cylinder dimensions: 17 & 26x24 in
Grate area: 26 sq ft
Tractive effort: 38,000 lbs
Weight: 211,000 lbs
Fuel: 1,000 gal oil
Water capacity: 2,000 gal
Service History:
1929 -1931: Hammond Lumber Co. #6. Mill City, OR.
1931 – 1936: Hammond & Little River RR #12. Samoa, CA.
1936 - 1942: Hammond Redwood Co. #12
1942 – 1951: Hammond Lumber Company #12.
1951 – 1956: Arcata & Mad River Railroad #12. Blue Lake, CA.
1956 – 1959: Southwest Lumber Mills #12. Flagstaff, AZ.
1959 – 1960: Southwest Forest Industries #12. Flagstaff, AZ.
Almost all of this info is to be credited to Jon Davis
His web site is: