1996Best Show Yet for Connecticut Antique Machinery Association


| September/October 1997



Skinner engine

Skinner engine. Greene engine across the aisle, and below.

Vice President sent to us by Robert, Hungerford 47 Clinton Avenue Westport, Connecticut 06880

The main event of the year was the running of the Skinner Universal Uniflow engine. The Uniflow is the ultimate in steam valve construction and the most efficient of steam engines. The Uniflow valve design means the steam enters not just one side of the piston and then the other, but both sides at once! How can the engine run, you say? 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.

This engine was originally in the Rocky Hill, Connecticut, Veteran's Hospital and was an auxiliary generator. It was donated to CAMA two years ago and we have spent a great deal of time on it, from getting it disassembled and ready for trucking, to the first running of the engine in Kent, which was on the first day of the '96 show! (phew!) How momentous an occasion! This was the moment we got all steamed up about! The crowd stood watching as the final adjustments were completed and the steam valve was opened. The engine ran for the first time at CAMA. Bob Hungerford was the key to operation and I think he did a great job of organizing it and making it come together so well. 'We ran it at slow speed to see if things were right, and we heard a thud in the connecting rod bearing. After some more adjustments we tried again. The floor still shook a little, but we gained on it and finally got the knocks out. When we were sure, the covers were put on and the engineers gradually opened the throttle to full blast and the engine only went about 100 rpm, the maximum boiler output, but a fraction of the 225 rpm normal operating speed. Then they shut it down and congratulated each other, for the engine had run and the whole project had come to a wonderful close. Now all that is needed is to shine it up and make it generate once again, maybe next year.

The other engines in the Industrial Hall include the Tiffany and Pickett engine, which is another large engine like the Skinner, but instead of a generator, this one drove an entire factory with lineshafts and belts. The engine is based on the designs of Noble T. Green and is more efficient than others before it. This engine with a 12 foot diameter flywheel, had the inertia to power all the machines in the factory, and it only ran at 150 rpm. Due to the size of the flywheel, the speed up of the lineshaft was a multiple of the diameter and it might have turned six hundred to one thousand rpm.

The newest addition to CAMA is the Oil Field Pump Engine Building. This building was put up in late summer, and the engines were in and on display before the show. What an accomplishment! When Ray DeZara starts a project, he carries it through and finishes it quickly! Quite an asset to the Association, I might add. The engines in the barn are single cylinder hot tube and spark ignition. The first engine next to the side door is a big red Oil City Boiler works engine built in 1905 and has a 9 inch bore and 16 inch stroke, which is 300 cubic inches. It also has a really neat governor on it called a pendulum governor. This is simply a weight fastened to the exhaust pushrod that opens the exhaust valve only below a certain speed. This one is four stroke and water cooled. However, when engines of this type were in operation, they pumped crude oil and used some of it for cooling. By pumping it through the jacket that surrounds the cylinder and running off the natural gas that is on top of the oil in the well, it made for an efficient setup. Now these run on propane, which has a lot more BTUs than natural gas and so while starting the engines they tend to flood easily, but have more power. The second is a 1906 Oil Well Supply Simplex engine, which is very similar to the first, and has a centrifugal governor and dual ignition. The third big engine was built by Pattin Brothers before 1910 and is two stroke and hot tube ignition. It was used for drilling and is 15 HP. Flywheels are four to five feet in diameter on all of them, and they did not have a throttle, but were hit and miss.

The hot tube, made from nickel, is different from spark ignition. It is similar to a glow plug, but not quite. The tube is heated by a burner that surrounds it. To start the engine, you heat the tube until it glows red hot, then you turn on gas to the intake and crank the engine. The compression stroke pushes the gas into the head and the tube, which being red hot fires the charge of gas and drives the piston back. Getting the tube and the head hot enough is the key to easy starts, especially in cold weather! Timing of the engine is accomplished by changing the length of the tube, shorter tube fires later. The two stroke engines can backfire through the porting in the cylinder. If the gas leaks by the piston, it builds up behind it and could fire the wrong way. These were really an attraction and definitely benefited the event. There are more engines in the future to be installed in this building and I hope to write about these as well.