Connecticut Antique Machinery Association Preserves Skinner Engine

Engine room

Loading out from the second-floor engine room.

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47 Clinton Avenue Westport, Connecticut 06880

For collectors and preservers of old machinery, what a wonderful world it would be if mass, money and manpower were of no consequence when gathering treasures. Alas, in the engine hobby, and particularly for those of us in the non-profit museum arena, machinery is usually large, funding is limited, and our workforce is primarily volunteer.

Disassembly is under way. John Stauffer and Ray Dewley are removing the eccentric straps (note the ear protectors; it was noisy in the powerhouse!).

It's my hope that those of you familiar with these obstacles might be encouraged by this article to undertake saving the larger engines. It can be done! I know it can, because here at Connecticut Antique Machinery Association (CAMA), we've done it.

We are proud to have among our displays a fully-operable Skinner Universal Unaflow steam engine, along with the alternating current generator it powered. The engine is a right handed side crank engine, with an 82 inch diameter flywheel. Normal operating speed is 225 rpm, and alternator capacity suggests that the engine is probably about 250 horsepower. The 187 kVA, 2300 volt, 60 hz three phase alternator was built by Crocker-Wheeler in Ampere, New Jersey. The 7.5 kW 125 volt direct current Crocker-Wheeler excitor dynamo is driven from a pulley located on a section of the engine crankshaft that extends beyond the pedestal bearing. The entire set takes up 12 x 16 feet of exhibit space.

Until 1994, the engine and generator were housed on the second floor of the powerhouse of the Rocky Hill Veterans Hospital here in Connecticut, under ownership of the Veterans Administration. Installed new in 1938, the engine was last used regularly in 1975, but had been maintained for standby service to back up the hospital's Terry steam turbine driven generator set.

When the time came to take the engine fully out of service, the Veterans Administration was persuaded to transfer its ownership to CAMA's landlord, the Connecticut Bureau of Parks and Recreation. The VA also granted permission to our volunteers for disassembly of the engine in the working powerhouse.

With that permission granted, CAMA members found themselves in an uncomfortable position: this was not just some 'basket case' we were rescuing--we would actually be tearing apart a well-cared-for and operating piece of machinery.

Members began arriving at Rocky Hill around 10:00 a.m. on February 4, 1994 to document on videotape the Skinner's final run in its soon-to-be-former home. The power plant staff didn't ease any of our pangs of conscience as they noted that, 'Look! The exciter is still putting out current!' and the like. With the able Conrad Milster of Brooklyn's Pratt Institute operating the camera, we got what we needed on tape and were ready to leave by 1:00 p.m. Next task: to dismantle the engine (carefully!) and get it ready for the trip to its new home in Kent.

From the start of the entire process, we made certain that each step was completely documented on film. This photo record, along with field notes and sketches, was done to document the engine and relationship of various component parts so that the engine could be put back together. In effect, we were creating the assembly manual as we disassembled the engine.

We literally took over the engine room. It was a winter job, the engine room quite warm and very noisy. They had several steam turbines running the whole time we were there. We did not work without wearing ear protection at all times. The electrical switchboards next to the engine were in use as we worked, but we really took over with blocking, cribbing, and rigging everywhere. We met on Saturdays; the process of taking the engine apart, prepping it, and mounting it on skids for the move took ten of those Saturdays, with an average crew numbering four.

The hardest piece was the last. It was the cylinder and main frame assembly. We had to use jackhammers to break up the grout which held this piece, and then it had to be jacked up above the foundation studs. Then we jacked it even higher, in order to build a set of wooden skids under it. After that it was again jacked so that a plank floor could be laid under the skids, and we added rollers in between.

The door that everything must go out; watch that first step, it's twenty feet down. The second floor machine in the left foreground is a turbine generator, which was constantly on--what a noise it made while generating electricity!

We then had to roll this largest piece out and, as it was rolled, turn it 90 degrees to line up with the alley out to the door. At the beginning of this move, this heavy piece had to span and roll over the planked-up flywheel pit to line up with the alley and doorway.

Once all of the engine pieces and all of our gear were removed, we went back to the powerhouse with a transit and a level. There we measured all of the dimensions between the foundation bolts and made a set of drawings so we could pour a new foundation for the engine at our museum.

Moving day from the Rocky Hill hospital was the most exciting. The trickiest piece to move was the cylinder/frame assembly. It was heaviest at the cylinder end, which came out last from the doorway. The rigging company (Industrial Riggers) are members of CAMA, as are the owners of the trucking company. The large engine pieces filled up the trailer.

A couple of days later, we began the unloading process at CAMA grounds in Kent, where we put a forklift to work placing the pieces above the newly-poured foundations.

We then reversed the process undertaken at Rocky Hill, and reassembled the engine using our photos and field notes for guidance. When we got stumped, we had the good fortune to be able to call Mitch Koral, Field Engineer, Retired, Skinner Engine Company, who lives in North Carolina. We called him several times during the disassembly and reassembly, and his help and guidance speeded up the process and helped to insure that the engine would run again.

Engine reassembly took the same number of people in the crew approximately 20 days, spread over a two-year period. We leveled and aligned the main frame, cylinder, and outboard, with the crankshaft set in and leveled and squared. The stator cage was moved over to encircle the rotor. With the help of a gantry frame, we were able to put the flywheel halves in place and bolt together and install the governor controls. We cleaned and installed the eccentric straps and valve rods, then the exhaust valve cages, and then repiped the pressurized lube oiling system. When in Rocky Hill, the engine was on the second floor of the powerhouse and the steam line had been attached from the floor below; thus we had to remove the steam intake manifold from the cylinder casting and invert it so the steam supply is directed into the manifold from the top of the engine. Finally, after attaching the steam feed and exhaust lines, the engine was ready for testing.

The big day, the main event of our year, came on September 28, 1996, when the Skinner engine was first run, at CAMA's fall festival. It has been operable ever since.

Still to be done is the connecting of the condensate lines and finishing of the concrete floor around the engine.

The Skinner Universal Unaflow engine, the ultimate in steam valve construction, is the most efficient of steam engines. The Unaflow valve design means the steam enters not just one side of the piston and then the other, but both sides at once. The trick is an imbalance in the pressure. A little more on one side so the piston travels toward one end and then runs into the lesser pressure at the other end, rather than no pressure, and uses compression to slow the inertia and help to push the piston back when the valve changes direction and the piston reaches the end of travel. After the valve changes the steam pressure, the piston is pushed back, according to the high speed design. The flywheel has a governor balance system on it that regulates the eccentrics, and consequently the steam inlet, faster than the main valve can take effect. This is required to maintain the generating speed. The Skinner Engine Company, located in Erie, Pennsylvania, manufactured and sold steam engines into the 1950s. The company survived, although they've diversified, and can still produce a steam engine today as a special order.

Organizations should not be put off by large projects, but should carefully analyze them to determine their historical significance and their viability, both in financial terms and in terms of their impact on the organization's volunteer base. These projects can be done, but will take volunteers away from other duties they are already performing, and a large project could burn them out.

To combat burnout, on each work day set small goals so the crew can finish the day with a sense of accomplishment, feeling good about what they are doing.

This job couldn't have been done without the financial backing of the Dibner Fund, the support of the officers, directors, and members of CAMA, and all the contributions of the volunteers who worked so hard to not only save but also set up this engine and fit it back together so it is able to run again for other generations to see.