C&NW 1385 Front Truck Complete, Cab Receiving Finishing Details

Work continues at a steady pace on Mid-Continent’s Chicago & North Western No. 1385 steam locomotive. SPEC Machine’s Steve Roudebush took some time out of his day on August 24, 2016 to show off the latest progress on the locomotive’s rebuild for this report.

The change most instantly noticeable upon walking into the shop was the shiny, like-new front truck sitting in the center of the shop floor. Like-new may not be a fully appropriate term, as considerable portions of the front truck are new. One wheel set had a goodly amount of life left in it and merely required machining to bring it into proper profile. The second wheelset had been worn quite thin and needed to be replaced with a brand new wheelset forged in Pennsylvania for the 1385. Binders, spring hangers and truck equalizers were also created new to replace heavily worn originals.

C&NW 1385 completed front truck

C&NW 1385 completed front truck

Additional work on the front truck included pouring Babbitt, lining the pedestals with bronze, and polishing pins and bushings. The front truck is fully complete and ready to be rolled under the locomotive, which is anticipated to happen sometime in September.

Above where the front truck will be rolled under, the pistons have been fully bored and the valve cages nearly completed. One of the valve cages that was found to have cracks is being replaced with a new one. The new valve cage is anticipated to be machined on SPEC’s CNC machine in the coming weeks. Work has also begun on the crosshead guides and valve gearing. After those tasks are complete, brake rigging and appliances will be next on the task list.

The two major components missing from the 1385 as it sits in the SPEC Machine shop is the cab and the boiler. To see the cab, we took a short drive to the shop of Loren Imhoff. Imhoff has graciously donated all his time spent working on the cab. Inside was a nearly complete cab. Already quite sharp looking with a bright green interior and a black exterior, another coat of paint will be added inside and out. The ceiling vent, which had proven to be a challenge due to limited available drawings, was complete and functioning. A few items remained to be completed: the ceiling needs a few boards painted and installed yet, the windows need a few hardware items remade to replace lost or broken originals, the seatboxes are not yet constructed, but all is expected to be completed by October and the cab brought to SPEC Machine so it can be made ready to mount to the frame and the roof weatherproofing material applied.

The other major component on which the 1385 Task Force has focused a great deal of attention on lately is the boiler. It has taken longer for the boiler to reach construction phase than was originally anticipated, but this was one area of the locomotive rebuild that was not to be rushed in any way. As the single most expensive component of the project, there is no room for error. Finally satisfied that the boiler design is ready for production, the 1385 Task Force has now begun gathering quotes for manufacturing of the new boiler. Once a vendor is selected and the order signed, production is expected to occur fairly quickly.

Front Truck Wheelsets Receive Turn on the Lathe

A quick update on the Chicago & North Western #1385. Earlier this week, one of the front truck wheelsets was being turned on a lathe. Work on these wheels is being carried out by Harvey Diversified Trades. (Pictures via Harvey Diversified Trades LLC Facebook page). The job prompted the Harvey Diversified Trades Facebook page to write “I used to think this lathe was big until we put a locomotive axle and wheels on it.”

Machining C&NW 1385 pilot wheel

“Finished up the week machining on the front wheels for the 1385 steam locomotive for Mid-Continent Railroad Museum. Certainly kept the machine firmly on the floor….they are heavy.” — Harvey Diversified Trades Facebook

Two of the four 28″ lead truck wheels (pictured) are being retained and machined to specification, while the other two wheels were worn enough to necessitate replacement with brand new wheels. The new wheels were produced at a forge in Pennsylvania and delivered to Milwaukee, WI to be pressed onto the axle by NRE Wheel Works.

Both wheelsets will return to SPEC Machine in Middleton, WI where they will be united with the front truck assembly which has been undergoing repair work there.

1385 Status Overview

Jeff Bloohm, President of Mid-Continent, has shared a brief overview of the Chicago & North Western No. 1385’s status.

Here is an update as to where the 1385 is towards completion:
Frame work including driving boxes save fitting the boiler mounts and furnace bearers, brake cylinders and valve gear pivot points is finished.

Work on the drivers is finished. Work on the rods save the wristpins into the crossheads is finished. The cylinders are finished. One valve cage is finished, the other about 40% done. Work on the drive wheel suspension is finished. The cab is 75% finished.

Work is now concentrating on the front truck and that is about 60% finished. The axles have been inspected and journals polished. The bad set of wheels has been pressed off and the new wheels are being machined. The wheels on the other axle are also being turned. The boiler design is within weeks of being ready for 3rd party review.

Work yet to be done:
Final teardown, cleaning, inspection and repair plan for the valve gear, pistons, valves, and brake rigging. All appliances still require inspection and repair planning. The superheater header, ash pan, and stack require close inspection and repair planning. The fountainhead and all valves need inspection/repair/replacement.

After delivery of the boiler, the jacketing will need repair/refitting/rework.

Mid-July 2015 C&NW 1385 Update

Although updates have been a bit sparse of late, activity on the Chicago & North Western #1385 has continued forging ahead. The work completed in the last few months is not the kind that make great headlines, yet all of it is equally important toward achieving an operational 1385. Without further delay, here is the latest:

  • The driving boxes, shoes, wedges and hub liners are all now complete, save any modifications needed for grease or oil lubrication and any adjustments found necessary at final assembly of installing the drivers into the frame.
  • The footplate has been fitted, holes reamed, and tapered bolts installed to hold it place.
  • The locomotive’s spring rigging has been fully rebuilt. It is being installed onto the frame and will be stored in place unless it proves to be in the way of other work.
  • Most recently, work has begun on the machining and renewal of the connecting rods and bushings.

Other tasks coming up in the near future (In no particular order) include:

  • Rebuilding of the front truck.  The wheels on the front truck are currently being assessed as to whether they can simply be re-profiled and still offer adequate service life, or whether replacement is necessary.
  • Renewal and machining of the valve cages.
  • Cleaning/polishing of the finished rods.
  • Boring of the cylinders.
  • Cleaning and test fitting of the valve gear to determine wear and repairs needed.

The 1385’s new boiler is nearing the end of the engineering review phase and is expected to enter the build phase within the next several months. The boiler will be discussed further in a future post.

Photos provided by Brian Allen. View full album at https://www.flickr.com/photos/7777754@N08/sets/72157655692852722

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Driving Wheel Repairs Completed

Late January marked the return of Chicago & North Western No. 1385’s driving wheels to Wisconsin after nearly 10 months away. All three sets of the locomotive’s 63-inch drivers were sent to Strasburg Rail Road on March 24, 2014 to receive a range of repairs using Strasburg’s specialized machinery and expertise in the field of completing such repairs. Here is a rundown of the repairs which encompassed approximately 350 man-hours of labor.

wheel diagram

Wheel Centers

Wheel centers are equivalent to the rims of an automobile. It the main bulk of the wheel and includes the central ‘boss,’ spokes and rim.

C&NW 1385 last received wheel work in 1994, four years before its final summer of running in 1998. Mid-Continent’s record of repairs from 1994 show that three of the tires were removed and wheel centers inspected at that time. They were 0.160, 0.127, and 0.124 (inches) out of round. By turning the tire seats on Strasburg’s wheel lathe it returned the wheel centers to perfect roundness and eliminated the need for wheel shims.

The wheel centers were also inspected using magnetic particle inspection, or ‘magnafluxing.’ It is a non-destructive testing process to detect surface and near-surface discontinuities in some metals. A few minor cracks were located in the process. To enact repairs, a steel sample from a wheel was taken and a welding procedure specially tailored to the wheels’ metallurgical properties then devised and completed.

Hubliner

Hubliners are metal disks that are mounted on the inward-facing side of the wheel centers and are designed to absorb the wear where contact occurs between the wheel and the driving boxes. While at Strasburg, one of the six hubliners was replaced while the remaining five were all refaced to provide a smooth, even surface.

hubliner and journal detail

Journals

Journals are the portion of the axle, just inside the wheels, where the weight of the locomotive rests.

No. 1385’s journals were found to have scratches and other minor issues. Polishing was attempted but the imperfections were found to be too deep. To bring the engine to mainline-ready condition, the journals were turned and then polished to produce a smooth surface.

By making adjustments to the journal, it was also was necessary to make corresponding adjustments to the journal boxes. The journal box is what transfers the weight of the locomotive from the frame to the axle. Inside the box is a crown brass, shaped to fit over the top of the axle. The crown brass must be a perfect fit so as to allow just a film of journal oil to form between the journal and the crown brass and thus prevent overheating from friction.

With the final dimensions of the journals now known, the driving boxes were sent to a local shop in Baraboo, Wis. to machine the crown brasses. Inspection revealed one of the six brasses worn beyond accepted limits and that brass has been replaced. The other five proved to have sufficient material left to provide a long service life.

Replace Crankpins

Crankpins transfer forces between the rods and wheels. The forward and rear drivers have smaller crankpins because they only connect to the center (main) driver via side rods. The main driver has a larger crankpin because it connects to both side rods and the main rod. To offset the weight of the larger crankpins and rods, the main driver requires a heavier counterweight.

crankpin detailThe main crankpins and the crankpins on the rearmost driver were found to be worn beyond American Locomotive Company’s standards and were replaced. The crankpins on the first driver were in good enough condition to allow for machining in order to renew the bearing surface.

 

Quartering the Crankpin Holes

In order to work properly, a driving wheel must be offset (rotated) by exactly 90-degrees from the wheel it is connected to via the axle on the opposite rail. As 90-degrees is one-quarter turn of a wheel, the process is called ‘quartering.’ The holes to receive the new crankpins were bored and then the crankpins themselves were machined in such a way as to maintain exact quartering.

Installing New Tires

Similar to how tires on a car are designed as readily replaceable items designed to absorb the wear of going down the road, a tire on a locomotive fits over the wheel center and is designed to absorb the wear of rolling down the railhead and use of the locomotive’s brakes.

Project volunteer, Ed Ripp, adds some detail:

“The tires that were on the wheels were the tires that were originally on the engine when it came to Mid Continent [in 1961]. The running gear work that was performed in [1994] included just re-profiling the tires, not replacement. With just 1,000 miles or so of running since then, some significant flange wear on one tire developed that was near FRA wheel profile condemning limits. In order to bring that one tire into compliance, all of the other tires have to be turned to the same diameter. This is due to the fact that the drivers are coupled together with the side rods.”

As a result, No. 1385 received new tires for all six wheels so they could all be equal in size with a lot of life to avoid the need for another round of maintenance in the near term. Several hardness levels are available from which to choose when having tire made, based upon expected usage and environmental factors. No. 1385 received Grade C hardness tires.

stack of locomotive tires

In order to prevent the tires from coming off in operation, they are custom ordered to fit down to within thousandths of an inch. They are sized approximately 1/16 inch smaller than the wheel center onto which it must fit. They are then heated to cause expansion, enabling them to slide into place. Once cooled, the fit becomes tight. Strasburg Rail Road took a video of the process and it is available for viewing on their YouTube page.

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Return to Wisconsin and Painting

Following completion of repairs at Strasburg Rail Road, the drivers were trucked to SPEC Machine where they arrived on January 22, 2015.

 

More images of the arrival of the driving wheel are available on photographer Brian Allen’s Flickr page.

Within a few days, the wheel centers along with various spring rigging components were painted black.

Meanwhile, progress has been made on the driving boxes and the beginning of reassembly of the running gear, but that will have to wait until another post.