Re: Sumpter #250, 251

Hi Kevin,

As Bret stated, the Sumpter Valley mainline was extensively upgraded in the years prior to the arrival of the mallets, so axle loading limitations were not really a problem.

However, you are correct in your assumption that visibility and range was a concern. As related to me by a former Oregon Lumber Company engineer and proven by some great early photos of the mallets on the SVRy, tenders were added but the side-tanks retained until it was established the mallets could make it between water stops utilizing tender capacity alone. At that point, the side-tanks were removed and scrap rail added under the running boards to mimic the weight (and thus adhesion) that fully loaded side-tanks once provided. Some trial and error ensued until the right weight/balance was achieved. I'm sure Bret, Jim Grigsby, Taylor Rush and others could provide more insight or photos on this subject.

Casey