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ot----class 31 thumpers

Very nice, and a good shot of using the web measuring dial indicator to check for
crank/alternator alignment or "webbing a crank".
 
I've done that same alignment check many times with a Starrett 696 crankshaft strain gauge. It is amazing to me how much a crankshaft can flex. On some larger diesel engines, there is a cold and hot strain gauge reading. Cold, the "top-to-bottom" reading may be a few thousandths low. As the diesel warms relative to what it is driving, it "grows" upward and the hot strain gauge reading will zero out.

Annually, I take a crankshaft strain gauge reading on the center crank steam engine at Hanford Mills. This engine sits on a stone masonry foundation with a separate stone pier foundation for a third outboard bearing which supports a crankshaft extension. The stone foundations are not tied together and sit on a bed of stone cobbles to allow free drainage (high groundwater conditions). After a winter, things do tend to move a bit. I usually wind up tweaking the mounting under the outboard bearing. I designed that bearing with jacking screws to move it "fore and aft", and shims under it.

I had last used my crankshaft strain gauge overseas on some Fairbanks-Morse OP diesel generators about 1979 and figured it would never get used again as I got into hydroelectric work. Lo and behold, in the early 2000's I found need of it again at Hanford Mills when we extended the crankshaft on the center crank steam engine.

Interestingly, crankshaft strain gauge readings on that engine disclosed that the main bearings (babbitt, poured in the engine frame & line bored) were not bored parallel to a level plane. I levelled across the crosshead guides with a Starrett number 98 level. When I took crankshaft strain gauge readings, I was all over the place top-to-bottom. A quick check putting the groove of the 98 level on the shaft disclosed the shaft was running uphill by a good 1/16th of an inch. Nothing to do but scrape a little more clearance on the outboard bearing and put a piece of shim stock under one side of the bearing base to try to match the incline of the shaft.
That zeroed the strain gauge readings out top to bottom.

Each spring, I recheck the strain gauge readings. Like the rest of the old mill, the foundations do move a bit. It's a good exercise to show people how alignment checks are done, and how a crankshaft can flex.

The other thought which struck me is that the outward appearance of the Mirlees diesel engine has some similarities to an Electromotive diesel engine. However, the Mirless uses a cast block and is a 4-stroke engine with a different type of fuel injector (did not look like the "unit injectors" used on EMD engines).

I did enjoy watching the youtube of the entire building of the diesel locomotives. Seeing how the framing for the carbody was built had me chuckling. Welders using shields they held with one hand, stick welding without gloves or welding jackets. Admittedly, the welds on the carbody framing were small and short, but a welder had to be catching an arc burn over a day of work.

I looked at that nice new and clean locomotive and wondered how long it would stay that way. In service, diesel locomotives get pretty dirty. I was chuckling when I saw the fellow demonstrating how easy it was to access and change brushes. By the time that becomes necessary, it is a dirty job, and often with more equipment crowded around that end of the generator. Then, I saw the intake air filters in the side of the car body, described as "oil wetted" type elements. Another dirty job, washing those sorts of filters. Done it with kerosene, strong detergent, and then blown them out with compressed air and let them dry.

I also wonder how clean those Mirlees engines stayed after some time in service. I've seen a few old locomotive diesels that seemed to leak as much oil as they pushed thru the lube system. Oil in locomotive diesels gets as black as midnight in a coal mine. Anytime I've worked on a locomotive diesel, I wind up with that black carbon soot in my skin for days afterwards, no matter what measures I took to keep myself clean. Changing oil filter elements is one of those routine/dirty jobs and mechanical repairs are at least as bad if it means getting into the engine.

I chuckled at presentation of how easy it was to maintain that locomotive, thinking of the mechanics (or fitters ?) who would work on it once it was in regular service.
 
Remember that most of the guys doing the maintenance would have been working on steam locomotives up until then. Diesel was probably clinically clean as far as they were concerned!
 
I've worked on both steam locomotives & diesels. I agree with Mr. Goldstein. It seemed like I got dirtier and it took a lot more work/scrubbing and time to get clean after working on diesels. Coal soot and steam cylinder oil and boiler scale come off a person a lot easier in my experience.

Funny story about carbon soot from large generator brushes- which will get a person as black as any chimney sweep:

Year ago at the powerplant, we were doing some maintenance and repair work on one of the 300 Mw hydroelectric generators. Specifically, we had rigged up an old lathe compound and were turning the slip rings in place, using the actual turbine to spin the whole unit. In essence, we had the world's biggest vertical lathe, having a potential of about 500,000 shaft HP, though we were only running with the wicket gates barely cracked open to get a little speed. With 257 rpm being normal synch speed, but with slip rings about 5 feet in diameter, we needed a much lower rpm to get the surface speed on the slip rings right for turning, even with carbide tools.

We were working away in the generator housing and due to the space heaters being turned on (to keep condensation from forming in the windings) it was HOT in there. We were all down to our tee shirts and sweating, but enjoying seeing the job of turning the slip rings coming off nicely. I had contributed the compound off a Seneca Falls lathe (ca 1905),and we had plenty to joke about that.

Meanwhile, the electricians were busy cleaning carbon dust, servicing the brush rigging and inspecting/replacing brushes. The electricians were getting a lot blacker than we were. We were joking up and back between the mechanical and electrical crews. One of the electricians was a good looking woman with a fine figure, in her 50's at the time, but undeniably a fox. This woman had worked as a bartender, tended to date men with fast/souped-up cars, and by her own admission was a "bad" or "wild" girl. She noted that I was nowhere near as dirty as the electricians and took a handful of carbon soot and smeared my face with it before I knew what hit me. The combined crews were howling with glee- I was the only person in management inside that generator. OK, I can take getting dirty, and I laughed along with everyone else. Then, that woman electrician decided my face needed washing since she had gotten it dirty. She began to peel up her sweaty tee shirt, showing off her hard belly and making all the moves one would associate with an exotic dancer. The whole crew was now howling and hollering encouragement. I outshouted the entire crew, ordering that woman to keep her tee shirt on and said I'd wash up in the mechanics' locker room, thank you very much. Talk about trouble ! Corporate had all kinds of policies about sexual harassment, and the deck normally is stacked against men in those sorts of situations. Even if the matter never reached corporate, I did not need trouble right there within our own powerplant. I thanked the lady for her kind offer of cleaning my face, and told her my wife (whom she had met and knew) would appreciate her concern but not her methods. We all settled down and got back to work. The story of the carbon soot and my declining the offer of having my face washed with that lady's tee shirt became a legend in the plant.

When I saw the youtube of the Brush locomotive and the fitter was demonstrating how easy/accessable the brushes on the generator were, I remembered the episode in our own generator with the carbon soot. We used to like to kid around a lot, and those were the days when we could. Corporate was constantly sending people up to the powerplants to preach about some new policy or other, sexual harassment being a major issue with them, along with political correctness and the like. We let it roll off our backs, in one ear and out the other. After 6 + years of retirement, I am back at the powerplant in a mentoring role. I daresay the environment has changed. Much more uptight than when I worked there, but then, about half the people I worked with also went out the gate into retirement. New workforce, new and tighter controls from corporate. Seems like when we'd work on the units we'd be yelling up and back, singing, joking, and really hitting it hard. Different times, newer generation, I guess. I still get kidded about the "face washing" and it's a story the old hands tell the young hands coming up in our plant. As for the lady who was so solicitous, she never made it into retirement. She died at 55, a few months shy of her retirement, due to cancer of the liver and pancreas. Whether it was too much exposure to solvents used in cleaning electrical gear, or whether it was too much wild living or some combination thereof is something we will never know. I went back to work in the plant and the lady's old working partners are still on the job and it saddened me to see them walking thru the plant without her. I guess anytime I handle generator brushes and get a little carbon soot on me, I hear her voice along with the crew's and it puts a smile on my face. Gotta love working with a good crew in a good plant.
 
As a young green employee, I worked on a line with a local stripper....talk about awkward.

I was scared about keeping a job, and she was "lettin' it all hang out"

Trolling...or maybe "dredging".....

and yes, saw her years later, and they had not been nice.
 








 
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