Putting on the Brakes (In a Good Way)

The Steam Readiness team is gearing up for the return of the C&NW 1385 next year. In late July an order was placed for a new water pump which is to be installed at the end of the line at Quartzite Lake. For the foreseeable future, it will serve as the museum’s primary locomotive water supply source. The water tower at North Freedom is not presently able to hold water due to deterioration of the wooden tank, plus it used to be fed by the Baraboo River, but the river’s poor water quality makes it unsuitable for future use. The museum’s well is only low capacity and is just adequate to keep up with restroom usage.

The new pump at Quartzite Lake is rated at 300 gallons per minute (the 1385’s rebuilt tender has a capacity of 7,500 gallons). A 2-1/2 inch fire hose will be utilized to get the water from the pump to a bottom-feed port built into the tender tank. This will eliminate the need for crew members to climb on top of the tender tank to take on water using the old water column—an important safety consideration given that many Mid-Continent volunteers are retirees and may not be as agile as the typical steam crews of yesteryear.

The 1385’s boiler progress continues to move forward at a steady pace. Initial assembly of some of the fundamental components identified several minor discrepancies. It was noticed that a few pieces of the raw material did not conform to the design tolerances. While the discrepancies did nothing to jeopardize the boilers construction, they did warrant an extensive review of the computations and detail drawings that support the firebox. This review was completed and addressed all of the issues adequately.

Continental Fabricators has spent the following weeks updating their engineering data to accommodate these revisions. This has caused some delay in the assembly of the boiler but fortunately no alterations are necessary. The task force members, working in conjunction with Continental’s Engineering team are nearing completion of this task. As soon as the data streams are re-aligned, work on assembling the boiler will resume. A new fabrication timeline will be developed as soon as work is ready to be resumed.

Meanwhile, Steve Roudebush and company at SPEC Machine have stayed busy working on other components of the locomotive. The photos and captions that follow highlight the recent work taking place at SPEC Machine’s shop in Middleton, Wisconsin.

Report by Jeffrey Lentz with contributions from Brett Morley and Steve Roudebush.

C&NW 1385 Update – June 2017

Brett Morley, the 1385’s boiler engineering expert from Performance Engineering provided a brief update on the 1385’s boiler production as of mid-June for the museum’s  member newsletter, the STEAMER. That article is reproduced here:

The flanged sheets worked on by Gary Bensman of Diversified Rail Services were completed and sent back to Continental Fabricators at the end of April. This was a little longer than we had hoped but the finished results were well worth the wait. I had instructed Continental not to proceed with any of the additional fabrication until the finished flanged sheets arrived and could be verified dimensionally. This proved to be a worthwhile wait as the sheets had to be altered a little in order to fit through one of Gary’s flanging dies. In order to fit his standard tooling he was forced to reduce the inside radius of the door sheet and rear flue sheet from 2” to 1.5”.

The deviation from the print does nothing to effect the boiler’s performance, nor would it be noticeable with the naked eye. It did however change the dimensions for the mud ring. We were able to adjust the boiler’s 3D model and produce a mud ring that fit the flanged sheets. Continental then proceeded to fabricate the mud ring to the new dimensions and ship it to SPEC Machine. It was test fitted for dimensional accuracy and all of the dimensions aligned as expected. While at SPEC we took the opportunity to drill and tap the underside of the mud ring to alleviate the need to do this after assembly. This negates the need to perform this task upside down ( a real pain). The completed mud ring was shipped back to Continental Fabricators at the end of May along with all of the new 5” flues that were previously housed at the museum.

Since the mud ring completion I have been updating the stay bolt layout for the throat sheet and backhead. The radius change required a slight change to the outer edge of the stay layout. We had known for some time that the original backhead layout needed some adjustment so this turned out to be the ideal time to perform this task. I completed the new layouts over in early June and began transferring them to Continental Fabricators on June 12th.

C&NW 1385’s Mud Ring Test Fitting Planned, Superheater Flues Readied

With Gary Bensman’s (of Diversified Rail Services) flanging of various boiler and firebox components complete, Brett Morley of Performance Engineering and the 1385 Task Force now have the dimensions needed to move forward with the updates to the SolidWorks 3D model needed to finalize the boiler design.  Waiting to get actual dimensions was important to ensure that what we build not only fits to locomotive, but also meets the requirements Continental Fabricators has in order to get everything to fit together.  The finished sheets from Gary look amazing. [Sorry, no new photos available at this time.]

We are back onto the task of laying out the stay bolts and other purchased items. Continental Fabricators (located in St. Louis) is preparing the mud ring at the moment. They will ship it to SPEC Machine (in Middleton, WI) as soon as it is complete.  We expect that to happen within the next week or so.  Once at SPEC, we will test fit the mud ring to the frame and make sure all fits as designed.  As soon as we have completed the test fit and made sure everything is aligned, the mud ring will be shipped back to Continental for final assembly.

Traveling along with the mud ring will be a total of 26 superheater flues, each 5″ in diameter and weighing nearly 200 lbs. a piece. The new superheater flues were fabricated and flanged previously and have been stored at Mid-Continent since 2010. These were loaded onto a trailer last week by Steve and Tyler Roudebush and taken to SPEC Machine to await transportation to Continental Fabricators where they will be installed as part of the boiler’s final assembly.

C&NW 1385’s superheater flues. This image was taken in 2010 when the flues were being placed into storage. In early May 2017 they were removed from storage and will soon be installed into 1385’s new boiler.

May is proving to be a very busy month for the 1385.  Years of careful research, analysis, engineering, review, and fundraising have led to this point where the new boiler is finally coming together. After the boiler is assembled by Continental Fabricators, it will be shipped to SPEC Machine this summer and set on the locomotive frame. At the same time as the boiler arrival, the locomotive frame/running gear will be moved from its current shop bay into a recently constructed addition to SPEC Machine’s facility designed specifically with the 1385’s needs in mind. The new addition can better accommodate the full height of the locomotive and will allow reassembly of the 1385 to continue unimpeded until it is ready for delivery to Mid-Continent.

To make a donation in support of completing the C&NW 1385’s rebuild, please consider visiting our Donation page.

Bending Steel Part 2: Forming the Throat Sheet

Gary Bensman and his team continued work flanging various sheets for the C&NW 1385’s firebox during the first half of April. Recent tasks included work on the 1385’s throat sheet and backhead.

This drawing of an Omaha Road Class I-1 boiler, a sister engine to the R-1 class #1385, identifies the location of the firebox, throat sheet and boiler barrel.

The backhead forms the rear end of the firebox and is located inside the cab. The fireman shovels coal into the firebox via a small door which will be cut into the backhead.

The already flanged (curved) sheet is the C&NW 1385’s new backhead. The backhead forms the end of the firebox inside the cab. Gary Bensman photo.

The throat sheet serves to connect the round boiler barrel with the firebox’s square-ish lower half. Such a transition requires the throat sheet to be a more complex shape. Where much of the bending of the steel sheets thus far could be accomplished via “cold flanging” by bending on a pneumatically-powered McCabe Flanger at room temperature, the throat sheet’s complex curves require a more hands-on approach. The “hot flanging” or “heat and beat” method involves heating the metal to make it more malleable and then using sledgehammers to pound it into the desired shape. The photo gallery below shows the throat sheet at various stages of progress.

Bending Steel

During the second week of March, SPEC Machine’s Steve Roudebush and Tyler Roudebush along with Brett Morley of Performance Engineering traveled to Tennessee Valley Railway Museum to meet with and assist Gary Bensman of Diversified Rail Services. Diversified Rail Services was contracted by Continental Fabricators to flange the four firebox sheets needed in building 1385’s new boiler.

Catalog page

The McCabe Flanger in a 1921 American Society of Mechanical Engineers Catalogue and Directory.

Flanging is a process to make a smooth bend in steel forms while the steel is cold. Flanging can also be done while the steel is hot but it adds more time, work and requires more people. The choice of whether to use hot or cold flanging is made largely on the shape being bent and where on the sheet of steel the bend needs to be made.

The machine seen in use here is a McCabe Flanger, a steam-era machine which uses pneumatic pressure for power. The bends are made a little at a time to prevent creating a wrinkle in the sheet.

The accompanying photos show the the aforementioned persons along with formation of the 1385’s rear tube sheet. The tube sheet forms the front of the firebox, meaning one side will be exposed to intense fire and combustion gases while the other side will hold back a wall of water. Before being installed, the rear tube sheet will have holes drilled for and support nearly 200 2-inch fire tubes and 24 superheater flues. The tubes and flues go through the water space of the boiler to conduct the combustion gases from the firebox to the smokebox at the front of the locomotive and allow the water and steam time to absorb more heat from those gases. The tubes and flues also serve to help support the tube sheet. Since the sheet is a large, flat surface, steam pressure is constantly pushing on it, trying to bow the sheet, but the tubes and flues mechanically tie together the front and rear tube sheets, providing strength and holding the sheets flat.

curved tube sheet

C&NW 1385’s new rear tube sheet takes shape. This is a view of a blend from a straight side to 12.5″ radius corner to 72″ radius crown sheet. Photo courtesy Gary Bensman. Mr. Bensman of Diversified Rail Services was contracted by Continental Fabricators to form the sheets for #1385’s firebox and tube sheets.

 

Above video courtesy SPEC Machine.