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  • Mini excavator stick

    Landscaper broke the stick on his JCB 8018. Pulled the stick off the machine & took it back to my shop. Clamped it to my table & jacked it back straight, vee'd it out & welded it up. Cut side & top plates. For the bottom of the stick (thumb side) I used a pc. of flat bar to extend the thumb base plate. Tried to make the stress point in a better area. Where it broke was where the thumb ended which also happened to be a stress area as the stick transitions be wider. It broke right on the weld for the thumb. Probably been cracked awhile & just got worse until it let go. Not many operators I know do a visual inspection everyday.

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    Last edited by MMW; 06-15-2014, 04:29 AM.
    MM250
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    Arco roto-phase model M
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    Miller spectrum 875
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    Syncrowave 250
    RCCS-14

  • #2
    I noticed that you contoured the side plates to reduce the stress concentration at the ends of the plates, similar to the original side plates on the upper end of the stick. I was wondering if you also contoured either the top or bottom plates, that you added?

    In any case it looks you made it a lot stronger than it originally was.
    Last edited by Don52; 06-15-2014, 08:12 AM.
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    • #3
      I run small equipment all the time and visual inspection is critical. We save a lot of downtime by inspecting. When I have new operators I try to instill the idea that inspection is not a once a day task. Every time you are around that machine you need to be looking at it.

      Nice work on the repair. The rounded corners look great. That should hold up for a bit longer now.
      Last edited by elvis; 06-15-2014, 11:42 AM.
      MillerMatic 251
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      A rockcrawler, er money pit, in progress...

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      • #4
        Nice repair. I realize space was probably limited, were you able to add any material to the top of that dipper?
        Obviously, I'm just a hack-artist, you shouldn't be listening to anything I say .....

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        • #5
          Is that thumb too big for the excavator?

          My friend did exactly the same thing to an excavator he rented for the day. He had some soft limestone ledge. I think he was smashing with it trying to break up ledge. These machines are durable, but not indestructible.
          Dynasty 280DX
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          • #6
            Same thing happened to me on my machine at home last week. Took the day off work to catch up on some things......
            Attached Files

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            • #7
              On the inside of the stick I put a pc. of 3/8" x 2" flat bar from the top of the thumb to past what I thought would be the new stress point because of the new side plates. This pc. is under tension while digging.

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              I also put a football shaped pc. on the outside of the stick. This did not break originally but bent. It is under compression while digging so I didn't feel the need to make a large pc. here just a small reinforcement of the bent area.

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              I'm not an engineer but try to use common sense & visualize where the new stress point will be after the repair. Hopefully it will be strong enough to survive for a long time.

              Don52 - I did make the ends of all my plates so I wouldn't be welding straight across the stick.
              Last edited by MMW; 06-16-2014, 06:23 AM.
              MM250
              Trailblazer 250g
              22a feeder
              Lincoln ac/dc 225
              Victor O/A
              MM200 black face
              Whitney 30 ton hydraulic punch
              Lown 1/8x 36" power roller
              Arco roto-phase model M
              Vectrax 7x12 band saw
              Miller spectrum 875
              30a spoolgun w/wc-24
              Syncrowave 250
              RCCS-14

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