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    Paddlewheel bearings

    Here's an engineering question: since the wheel shaft/journal sits in in large bearings, isn't the entire propulsive force of the wheel borne by these bearings? Are there any historical accounts of bearings breaking/overcome by the force of the wheel?

    #2
    Now that's a good question. It seems to me as if the BAY QUEEN had a problem with her wheel falling off while she was running, and the same sad tale can be told of the QUEEN CITY while she was engaged in the Louisville-Cincinnati trade. I'm not sure if it was a bearing problem that caused these two boats grief or if it was a shaft problem. In the back recesses of my mind, I seem to remember that the GENERAL WOOD cracked a cylinder timber and extensively damaged her fantail. Could it have been caused by the stresses put on by the machinery; to quote a flash in the pan politician, "You betcha!"

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      #3
      When they re-created the Delta King's wheel, they necked the shaft ends down to fit a modern roller bearing. Their original idea was the river current would turn the wheel with such a "frictionless" bearing. That didn't work, so they added a small electric motor chain driven to the shaft. The idea was to slowly turn the wheel--well, it's a real wheel, and the necked-down shaft snapped under the load.
      I would say that, yes, breaking happened!
      Consider the Railroad Steam Locomotive. All the power of the engine is carried by the piston rod and the main rod (the locomotive version of the pittman). That power hauls the entire train!
      Last edited by David Dewey; 06-12-2013, 01:29 AM. Reason: spelling error

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        #4
        Yes, I had one of the wheel bearings break on an excursion sternwheeler, back in the 1980s. Fortunately this happened while we were simply shoving ahead on a slow bell, at the dock, loading passengers. And the wheel didn't climb very far out of its location because the drive chain came off immediately. Obviously this was not a steamboat, but I'm sure it happened to other steam/diesel sternwheelers.
        I'm not sure if that "Babbitt" bearing was original to the boat's construction in 1929, but it was old, and we replaced them with Dodge roller bearings. It's my understanding that prior to modern roller bearings, steamboats used these rather simple Babbitt bearings.

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          #5
          While I've never seen a bearing come apart while underway (nor do I care to ever have such an experience), I've certainly heard them make an unholy din! The old saying I can recall, though, is: "It's better to hear them than smell them!" I have experienced very tight bearings and, unfortunately, had to go out or send some poor soul out to the wheel with a hose to cool them down! I always admired the pipe system on the Delta Queen designed to keep the journal bearings cool. If your bearing temp does reach or go above that critical temperature and you do not cool it down before you stop the wheel, then you're sure to have a mess on your hands when trying to start the wheel again as your bearings become one with your paddlewheel shaft! The bearing designs of which I'm familiar consist of three separate pieces. One piece--typically called the "pillow block" bearing is, as the name implies, the bearing on which the paddlewheel shaft rests. The other two are wedged on each side of the bearing. These side blocks have steel wedges driven between the bearing and the cradle fixed to the engine timber. There might be shims added to one side of the wedge to hold the wedges farther up towards the bearing cap where there are jacket bolts for adjusting the wedges. Chief Howe can tell a lively tale of the first set of journal bearings fabricated for the Mississippi Queen. As he can tell it with much more fanfare than myself, I won't say anything more than that first set of bearings were made of a much too hard bronze casting and immediately overheated the first time they rolled the wheel! Anyway, I have a few shots of some of the Belle's journal bearings. These also show a brass lip extending past the width of the engine timber to catch any side thrust. The Belle's bearings are designed with a removable wear plate for the side thrust (as one picture shows) specifically designed to prevent her shaft from the tendency to drift to the port side--another story in of itself!
          Attached Files

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            #6
            Fascinating discussion. I thought steamboats just ran. :-)

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              #7
              Not all romance and mint juleps...

              Originally posted by Ron Anderson View Post
              Fascinating discussion. I thought steamboats just ran. :-)
              Ron, wouldn't that be nice? Many people have the idea that working on a passenger steamboat is like being on a perpetual cruise. While it can certainly be fun and always interesting, it is work from the word "go". If there are no problems with bearings, packing, valves or (on and on and on) in the engine department, there can be busted paddlewheels, plumbing problems, hull leaks, broken steering cables, etc., etc. An excursion boat must be cleaned multiple times each day, and must look like the next load of pax is the first ones to ride that day...floors must be swept and mopped and waxed, trash must be gotten off, ice has to be carried and coke tanks filled. The wind blows, there's high water and low water, traffic. Passengers pay the bills, but they sometimes act like they've had no home training....they don't take care of their trash, they spill stuff, they make a mess in the restrooms. On excursion boats (especially on a Saturday night) they've been known to throw up (always so nice!). The list just goes on and on, and the hours are long. Even on Rafter Clyde's boat, with only professionals on board, problems crop up that make the pros scratch their heads. Wouldn't it be nice if steamboats just ran? Yeah.

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                #8
                Bob's note hit a chord this morning--probably because I have to leave soon, go in 2 hours early just to get the theatre ready for today's two performances. Mostly, with this group, cleaning the bathrooms. I always dread it when this group rents the theatre because they trash the bathrooms & go through the TP like it was water. They also trash the dressing rooms,)they throw everything on the floor--uneaten pretzel sticks, paper cups, etc. etc.) but fortunately the dance instructors told me they would clean their mess up--I just have to lug all the trash bags up the stairs and out to the dumpster. When it's all over it'll still need REAL cleaning! (this is an old vaudeville theatre, and the dressing rooms are under the stage) Yesterday was 14+ hours, today will be 10+. I get the next two days off--and am looking forward to that!!
                Yes, what goes on behind the scenes, hopefully the public never sees--if we are doing our jobs!
                Sorry for the rant--it's been a long week!

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                  #9
                  Ron, here: Live Steam by Jon Kral | Barnes & Noble is a good book on working on modern steamboats. This one is selling for $1.99, considerably less than I paid for my copy! I also recommend "Moonlight at 8:30" by Capts. Clarke Hawley and Alan Bates.

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                    #10
                    Ironically that Live Steam book ships from a book store in northern Indiana, not far from where I was operating the sternwheel excursion boat that broke her wheel bearing in the 1980s (as I had posted above). How's that for irony?!

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