Damaged bearings in wire drive strut

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  • Ronbo
    Senior Member
    • Jul 2010
    • 121

    #1

    Damaged bearings in wire drive strut

    Im having an issue with my bearings in my scale hydro, on .078 wire. I was told the strut is new, my bearings are new (bought a set of 4, flanged and non.)

    I managed to make it through a race day, but I damaged 4 bearings, 2 flanged and 2 non total, including 2 test sessions a week before. I was told that my prop was probably out of balance, but its a carbon prop that had been ran by one of our top racers. My robart balancer just wont do something so light..

    My motor runs really warm, about 120-130 , (feels more like 140 )on temp gauge, more so than the first run i did over a week ago.
    I did remove a washer the last test runs after the race, and it seemed to have gotten better. the bearings seemed fine. the washer wasnt perfect match, so could have cause a vibe?

    What am i to look for in setting up the drive dog, bearings, grease etc? right now, it feels pretty smooth. I use just thin film of grease in case the wire rubs the sides of the stuffing tube? I realize its hard to analyze not seeing the setup.

    What simple balancer (magnet?) could I buy to balance carbon and then metal props?
    Ron
    1/10th 2014 U-6 Oberto ,1999 U-6 Miss Madison, 1971 U-6 Miss Madison, 1976 U-6 Miss Madison Unlimited Hydros
  • JimClark
    Fast Electric Addict!
    • Apr 2007
    • 5907

    #2
    Where did you get the bearings
    "Our society strives to avoid any possibility of offending anyone except God.
    Billy Graham

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    • Ronbo
      Senior Member
      • Jul 2010
      • 121

      #3
      Boca bearings, green seals.
      Ron
      1/10th 2014 U-6 Oberto ,1999 U-6 Miss Madison, 1971 U-6 Miss Madison, 1976 U-6 Miss Madison Unlimited Hydros

      Comment

      • JimClark
        Fast Electric Addict!
        • Apr 2007
        • 5907

        #4
        How bout pictures of our strut setup and where the bearings are located. Something sound's weird here. Are all 4 bearings in the strut?
        Also I assume this is a modern CT 1/10th what motor and prop?
        "Our society strives to avoid any possibility of offending anyone except God.
        Billy Graham

        Comment

        • teach
          Senior Member
          • Jun 2008
          • 509

          #5
          I just went through the same thing with my LSH boat. 6 blown bearings in about a week and a half. Prop was balanced fine. I think my drive shaft was just to long (22") causing a weird vibration when I gave it full throttle with no load. It's just a theory though. Maybe it was just piss poor luck.

          Comment

          • DPeterson
            Senior Member
            • Apr 2007
            • 842

            #6
            teach
            6 blown bearings in about a week and a half.
            I just met this teach guy out at the Colorado Nats. I am not sure he has his bearings straight. So I would really think about what he has to say.

            Just kidding. It was great fun messing with teach and I believe he knows what is going on.

            Doug
            Doug Peterson
            IMPBA 19993
            www.badgerboaters.com

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            • tharmer
              Senior Member
              • Mar 2009
              • 342

              #7
              I had the same problem. It turned out that the wire was not exactly aligned with the bearings. The side load trashed them. they were good bearings.

              So, make sure the stub shaft is exactly aligned with the two bearings with absolutely no side load. Then I suspect you'll be fine.

              -t

              Comment

              • teach
                Senior Member
                • Jun 2008
                • 509

                #8
                Originally posted by DPeterson
                teach


                I just met this teach guy out at the Colorado Nats. I am not sure he has his bearings straight. So I would really think about what he has to say.

                Just kidding. It was great fun messing with teach and I believe he knows what is going on.

                Doug
                Hah! The wheels on the bus go round and round.

                Comment

                • Ronbo
                  Senior Member
                  • Jul 2010
                  • 121

                  #9
                  modern hull, 2 bearings in strut, 1 flanged 1 non flanged. Ive pushed the strut back up for setup reasons, as it was down fully to set up the hydro. Ill try to post pics later.

                  I have the drive dog against the bearing, but I want to pull it out a bit to leave a gap?
                  Ron
                  1/10th 2014 U-6 Oberto ,1999 U-6 Miss Madison, 1971 U-6 Miss Madison, 1976 U-6 Miss Madison Unlimited Hydros

                  Comment

                  • JimClark
                    Fast Electric Addict!
                    • Apr 2007
                    • 5907

                    #10
                    leave a gap for sure
                    "Our society strives to avoid any possibility of offending anyone except God.
                    Billy Graham

                    Comment

                    • Ronbo
                      Senior Member
                      • Jul 2010
                      • 121

                      #11
                      How much of a gap tho? .005 to .010" or so?

                      scorpion 3026-1900 on a graupner k45. Not sure what it will do on an octura
                      Ron
                      1/10th 2014 U-6 Oberto ,1999 U-6 Miss Madison, 1971 U-6 Miss Madison, 1976 U-6 Miss Madison Unlimited Hydros

                      Comment

                      • AlanN
                        Senior Member
                        • Mar 2008
                        • 334

                        #12
                        Wire drives are finicky. If the wire has a bit of a wobble will wear out the bearings. I used to loctite mine into the struts and a friend of mine would insert his loose. Mine seemed to last longer but was harder to replace. Everything must be very straight and clean on a wire drive. The c/f prop should not be an issue unless it is really torn up. I would leave only a very fine amount of space from the dog drive to the strut...maybe a few .001's. The more of a gap you have the more load on the wire and will bend the wire to cause more vibrations. Gave up running them due to the maintenance....cables are almost as good for performance but far better for maintenance and regular running.

                        Comment

                        • properchopper
                          • Apr 2007
                          • 6968

                          #13
                          I've found that the rearmost flanged bearing had insufficient "shoulder" to stay aligned with the strut. Once worked loose, the resulting wobble caused havoc with it and the front bearing.I've discussed this with Mr. Wohlt and as a result the rear bearings in his subsequent (and my) strut (s) are now non-flanged. I have Red loctited the bearings in to keep them aligned and run minimum tolerance between the drivedog and strut. I have had trouble removing bearings to replace, and now have one strut in which the outer race is permanently stuck in the strut, and being stainless is impossible to drive out or dremel.
                          2008 NAMBA P-Mono & P-Offshore Nat'l 2-Lap Record Holder; '15 P-Cat, P-Ltd Cat 2-Lap
                          2009/2010 NAMBA P-Sport Hydro Nat'l 2-Lap Record Holder, '13 SCSTA P-Ltd Cat High Points
                          '11 NAMBA [P-Ltd] : Mono, Offshore, OPC, Sport Hydro; '06 LSO, '12,'13,'14 P Ltd Cat /Mono

                          Comment

                          • AlanN
                            Senior Member
                            • Mar 2008
                            • 334

                            #14
                            Tony,
                            try hitting the loctited area with some flame. I like to use a small butane torch. It's tough to get the right spot but when it does melt the bearings will come out easily.

                            Comment

                            • Steven Vaccaro
                              Administrator
                              • Apr 2007
                              • 8720

                              #15
                              Or try a good soldering iron.
                              Steven Vaccaro

                              Where Racing on a Budget is a Reality!

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