Monday, July 6, 2015

Tender tank gets wheels

Tender tank project volunteers and staff pose with the new tank on the tender frame.A major milestone was achieved on the Northern Pacific Railway steam locomotive 924 last week: substantial completion of the new cistern (tank) for the tender.  For more than five months, a replacement tender tank has been taking shape on the floor of the Conservation and Restoration Center.  Other than a couple additional baffles and the rear coal board, all structural and seam riveting was completed such that is was time to move on to other aspects of the project.  The tender frame had already been rehabilitated and prepared for placing the tank some weeks before.  

During this phase of the project, additional research determined that this tender frame is actually far more ancient than the locomotive and tank.  The tender frame and trucks were originally built for a Northern Pacific 4-4-0 C class locomotive in the early 1880s, predating the construction of 924 by more than 15 years.  Later in 924's service life for the NP, the original frame and trucks were replaced by the running gear from one of the many 4-4-0s that were being retired in the 1910s and 1920s.  Contemplating the implications, this tender frame hardware and trucks were potentially in service prior to completion of the Northern Pacific as a transcontinental railroad!

Remachined bottom valve installed on bottom of new tank.
Before the tank could be placed on the frame, the water valves at the ends of the water legs needed to be remachined and installed in the floor of the tank.  The lack of access and upside-down nature of this work would have made it very difficult to install once the tank was in place.  The valve bodies were faced, bored, and valve seats recut using one of Museum’s large lathes.  Then the valves were fitted into position, holes drilled in the base of the tank, and mounted.  

Large loader lifts new tender tank from floor in Conservation and Restoration Center.With the bottom valves in position, it was finally time to install the new tank on the tender frame.  Weber Construction is the Museum’s neighbor and is also owner of the local rock quarry.  Their repertoire of machinery includes large excavators and loaders that each can lift tens of thousands of pounds.  So Weber was hired to perform the lift and arrived Friday, June 26th with a very large loader with forks mounted on the leading edge.  The 16,000 pound tender tank was picked up from the floor, removed from the CRC and placed on the frame.  Everything fit perfectly the first time, and the total elapsed time from start to finish was just two hours!

A significant amount of work remains to be done on the tender before it is ready for service. The tank requires installation of the rear coal board, filler hatch, four small baffles, hand rails, rear headlight, additional seal welding, and interior and exterior paint.  And not to forget, large white numerals proudly displaying her number!  However, the shop floor is now open and uncluttered so that Museum forces can begin placing and powering up the new large machine tools that were acquired earlier in 2015.  This will allow work effort to slowly transition to the locomotive and its many needs.

New cistern on tender frameThis achievement was made possible by the hard work and sacrifice of many museum volunteers and staff, and is a testament to the scale and quality of work that can be accomplished through teamwork.  At this time, there still remains much work to complete 924's return to operation.  However, the list just got a lot shorter!
--Special thanks to Dave Honan for taking photos of this special day, and to Stathi Pappas for providing the content of this post--