Saginaw Timber
Company No. 2
Restoration Journal

steam locomotives number 2, number 1385, and number 1

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Year: 2014 2013 2012 2011

Blast Pipe, Branch Pipes and a Surprisingly Resilient Air Compressor

June 8, 2014

The latter part of May and the first week of June has seen continued work on the innards of the smokebox and work on Saginaw Timber Company #2's appliances. Chuck Ham gave a short update on the work as of the final days of the month of May:

In the last week the blast pipe that directs exhaust steam up the stack and the branch pipes that carry steam to each side of the cylinder casting have been reinstalled in the smokebox. This was accomplished after much trial, error and careful fitting and repair of worn and corroded parts. Then work focused on the air compressor. It was connected to the shop air supply and, after 10 years and a flood, was found to be fully functional. The compressor is now being needle scaled in preparation for painting and installation on the locomotive.

Ken Hojnacki, another project volunteer, added:

Today [May 27] was a great day to work on the 2. Skip was needle scaling the airpump after having successfully operating it on the ground. He was surprised it started so easily after sitting all these years. I was able to needle scale the paint and rust from parts of the right side #2 and #3 drivers and started on the #1 tire.

By May 30th, the air pump had a nice coat of green paint and was installed onto the locomotive on June 1st.

Dave Wantz was on hand to assist with the installation of the branch pipes and has supplied the following series of photos documenting the process. Clicking on the images will load a larger version of each image.

Delivery end of dry pipe at front tube sheet. New dry pipe installed during the 2012 rebuild.

Installing smokestack.

Right branch pipe.

Test fit of right branch pipe.

Skip Lichter relaxing while lapping in right grind ring.

Right saddle seat for branch pipe. Approximate 30 degree seat.

Left saddle seat with anchor screws applied for high temperature J-B Weld.

Tool for forming 30 degree seat.

Installing right branch pipe.

Installing right branch pipe.

Bottom in place, now swing over.

Right branch pipe installed.

Mushing tool to form high temperature J-B Weld.

J-B Weld in seat.

Left side upper grind ring. Recut seat and formed with disk sander to +/- 0.001.

45 degrees to center of radius but ring is almost too big for tee as this is about 1/2 larger than center of 45 degree seat in tee.

Tee seat 45 degrees. Note that grind zone is way outside center of seat, about 1/2 inch on diameter. May have to make new rings for both sides.

Left grind ring at tee. Note extra large size.

Reshaped curve seat for left side. Center of curve at 30 degrees to back of ring to match cylinder.

Left cylinder fit after grinding in ring.

Done! Branch pipes installed.

Air Compressor being prepared for testing.


Smokestack Installed and Some Smokebox Science

May 19, 2014

To begin this post, there are some new photos to share which show the smokestack now installed.

Saginaw Timber Company No. 2 with smokestack installed. Richard Colby photo.

View into interior of smokebox. Richard Colby photo.

Following the last post, a short addendum was sent from project volunteer Chuck Ham:

John Risley mentioned having to level the locomotive. The reason for that was to align the center line of the smoke stack with the exact center of the exhaust nozzle. Those two parts must align exactly to create a Venturi effect for the smokebox to function as a vacuum to draft the firebox correctly. The function of the smokebox is very critical to the efficiency and power of the locomotive.

That explains why alignment is important, but it introduces a few concepts worth a little more explaining.

The Venturi effect is a phenomenon in fluid dynamics in which a reduction in fluid pressure results when a fluid flows through a constricted section of pipe, or in this case the exhaust nozzle. To be clear, fluid refers to either liquid, or in this particular situation, gasses. It is an extension of the Bernoulli’s principal which explains how the speed of air over the surface of an airplane’s wings produces lift and allows a Boeing 747 to fly.

The Venturi effect is similar to putting your fingers over the end of a garden hose to reduce the size of the opening. The result is that the same amount of water has a smaller opening in which to exit the hose and therefore must travel with greater velocity in order to keep up with the volume of water coming out of the spigot at the other end of the hose. The Venturi effect shows that this produces an area of low pressure at the point in which the flow of water is constricted (by your fingers).

This reduction of pressure is put to work in a steam locomotive. The exhaust nozzle is pointed straight up, blasting out the high-velocity, low-pressure steam up through the smokebox and out the smokestack. From science classes you may remember that pressure gradient force is the force which results when there is a difference in pressure across a surface. As high-pressure zones and low-pressure zones attempt to equalize, it creates a vacuum effect, or force, drawing  the higher-pressure smoke and hot gasses from the fire through the tubes and towards the lower-pressure jet of steam shooting out the smokestack. It short, the steam is “sucking” the smoke from the fire out the smokestack along with it. (Quotations are used around sucking because it is more technically correct to say the smoke is blown toward the low-pressure zone in the smokebox by the smoke and hot gasses' own high-pressures.) This draft in turn draws cool, fresh air through the grates and into the firebox, making for a more efficient fire and a more efficient locomotive.

Illustration of smokebox and Venturi effect. Illustration by Jeffrey Lentz.

The draft created by the blastpipe/exhaust nozzle is very important to maintaining a hot fire and enough steam pressure to move the train. Therefore, when the locomotive is stopped or coasting and there is no exhaust steam to create the draft, the effect is induced by a device called the "blower." A blower is a ring placed either around the base of the smokestack, or around the blast pipe orifice, containing several small steam nozzles directed up the chimney. These nozzles are fed with steam directly from the boiler, controlled by the blower valve which is operated by the fireman.

Getting back to the start of the post, leveling the locomotive was an important step to ensure the alignment of the nozzle was perfectly centered with the smokestack. If alignment were not good, then the jet of steam is not reaching its full potential to draw the smoke and hot gasses out of the smokebox, thereby creating a less efficient fire in the firebox and in turn requiring more fuel to operate.


2014 Work Begins with Backhead Plumbing and Smokebox Assembly

May 12, 2014

A long, snowy, windy and especially bitter cold winter delayed the resumption of major restoration work on Saginaw Timber Company No. 2 until fairly recently. With warmer weather finally making an appearance, the project is once again gaining momentum.

Chuck Ham, a project volunteer, reported in late April that work on reassembly of the backhead plumbing was underway as part of getting ready for the final Federal Railroad Administration hydro and steam test. The backhead is the end of the boiler which extends into the cab, and the plumbing refers to the piping, valves and gauges used by the engine crew. As of May 11, a test date had not been scheduled nor was an estimate made as to when it would take place.

Pace of work on the backhead plumbing was somewhat hampered. Ham explains, “It is unfortunate that when the locomotive was disassembled almost 14 years ago, no photos were taken. Skip [Lichter] is having to reassemble the locomotive mostly from memory.  It is slow and repetitive with much disassembly and reassembly to get things to fit correctly.”

John Risley, another volunteer working on the locomotive, wrote this short update on May 7th describing recent activities:

We removed the smokebox front today so we could work easier on installing the "T" to the dry pipe connection and fit the delivery pipes connecting the "T" to the saddle/cyl. The "T" has gone for machining a new seat as the old 45 degree seat was unusable. With a little luck it should be done very soon. The nozzle is ready to go in as soon as the studs are removed and replaced, then the stack can be mounted in its proper place. Taking the front off of the smokebox makes this difficult work easier. We removed the I-beam from under the boiler. We leveled the locomotive to the best of our abilities. One of the air jacks was acting temperamental but we got it working too. Moved the stack closer to where we can get at it easier. Removed the steam delivery pipes off the locomotive so we can work on them as well. And at the end we finished reaming the last two holes for the saddle bolts. All saddle bolts are installed except for these last two. Sorry no pictures, brought the camera but we kept busy and there were only three of us working so all hands were on deck so to speak. Didn't have time. The crew today was Gary Bensman [of Diversified Rail Services], Skip [Lichter] and myself. Right now at this time, we are working outside and that is really where we need to be. The weather today couldn't of been better.

Also had some visitors from Denver and Ohio who were visiting family in North Freedom stop in and asked for a tour. So they got one and stayed by the locomotive asking really good questions. They seemed to enjoy the visit and the kids were enjoying it too. Three generations spending a couple of hours at MC. Was really a very nice day to be at MC and we actually got some work done. Another small step for mankind.

Steam status page writer/editor Jeffrey Lentz was on site May 11 and captured the following photos.

Saginaw Timber Company No. 2 as seen on May 11, 2014. The front of the smokebox is at right, leaning against a boxcar.

No. 2, sitting just outside the Mid-Continent Railway Museum engine house on May 11, 2014.

Front flue sheet and inside of smokebox where efforts are currently focused.

Under the tarp and viewed from roughly floor level of where the cab will later be installed, the progress on installing plumbing on the backhead is visible. The large opening at center is the firebox door.

Running gear work was largely completed in 2013.

No. 2's smokestack (resting in front of C&NW 1385's boiler) awaits installation.



Year: 2014 2013 2012 2011

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Saginaw Timber
Company No. 2
Chicago & North
Western No. 1385
Western Coal &
Coke No. 1