1. Thank you for visiting HeavyEquipmentForums.com! Our objective is to provide industry professionals a place to gather to exchange questions, answers and ideas. We welcome you to register using the "Register" icon at the top of the page. We'd appreciate any help you can offer in spreading the word of our new site. The more members that join, the bigger resource for all to enjoy. Thank you!

Komatsu PC75UU2 offset boom to std one piece boom

Discussion in 'Excavators' started by Batkom, Jan 31, 2019.

  1. John C.

    John C. Senior Member

    Joined:
    Jun 12, 2007
    Messages:
    6,400
    Occupation:
    Machinery & Equipment Appraiser
    Location:
    Northwest
    What you could do is have a spacer machined to install inside the cylinder on the rod.
     
  2. Batkom

    Batkom Well-Known Member

    Joined:
    Dec 24, 2017
    Messages:
    139
    Location:
    Idaho
    Yes I actually asked the hydraulic shop that put the new cylinder seals in to do that.
    But they called after they had it apart and said due to the cylinders cushion design, it was going to be complicated.
    I did not go and look at what they were talking about, happened to be out of town at the time. Took there word for it and told them to leave it as it was and just put the seals in.
     
  3. John C.

    John C. Senior Member

    Joined:
    Jun 12, 2007
    Messages:
    6,400
    Occupation:
    Machinery & Equipment Appraiser
    Location:
    Northwest
    I hadn't thought of it having a cushion. Basically that is just something that blocks the hole for the oil to go through before the piston hits the end of the cylinder. I guess the slug might get in the way.

    The other idea is to just cut off the eye and enough of the rod to shorten the stroke. The problem I had doing that is that it also shortens the stoke in the opposite direction. I'm sure you will figure out a way to make it not hit the barrel.
     
  4. Batkom

    Batkom Well-Known Member

    Joined:
    Dec 24, 2017
    Messages:
    139
    Location:
    Idaho
    E988CB12-3A10-48B3-9F25-CFFADDC42E69.jpeg 0732FE68-01F3-425E-A3F6-9C70DABC8A65.jpeg EBC0622A-8BF3-45A8-B922-9483AB22C7BF.jpeg 06256E94-DA83-4C3B-98E1-0F7FC4C73A50.jpeg Got the 3 inches added!
    Here’s some pictures of it ready to weld
     
    John Shipp likes this.
  5. Batkom

    Batkom Well-Known Member

    Joined:
    Dec 24, 2017
    Messages:
    139
    Location:
    Idaho
    EF1DCD39-8D1A-4D00-AC71-BE4A52337A44.jpeg Almost done welding
    Preheated, 5 passes with .035 wire, 27 volts pulling 250 amps.
    Burns in real nice.
    Starts are seem little cold, but if you starts right on the edge that hot it all runs off - I do not claim to be a welding wizard!
    Ground the ends/ starts all out and then welded across the ends with stick repositioned.
    Will post finished pics Monday.

    Pretty happy with how it came out.
    Cylinder Barrel still touched just before cylinder bottom out, but, stick is curled to were the bucket will touch the bottom of the boom.
    Not a place where you would normally curl to except when hauling.
     
  6. Silveroddo

    Silveroddo Well-Known Member

    Joined:
    Jun 23, 2010
    Messages:
    229
    Location:
    Northern MN
    Good looking machine, did you make the side cover?
     
  7. Batkom

    Batkom Well-Known Member

    Joined:
    Dec 24, 2017
    Messages:
    139
    Location:
    Idaho
    Yes I did.
    It was missing when I bought it.
    Built that last year right after I bought the machine.
    Machine was a bit of a basket case cosmetically!
    But the engine ran/ runs very strong and the hydraulic pump had just been replaced. None of the cylinders leaked externally, and all the under carriage was in good shape.
    So figured for the money it was worth the effort to get it back in good operating condition.
     
  8. John C.

    John C. Senior Member

    Joined:
    Jun 12, 2007
    Messages:
    6,400
    Occupation:
    Machinery & Equipment Appraiser
    Location:
    Northwest
    It looks pretty good from here. Did you get any pull when you welded the ears. Are you planning on line boring when you are through with the welding?
     
  9. Batkom

    Batkom Well-Known Member

    Joined:
    Dec 24, 2017
    Messages:
    139
    Location:
    Idaho
    Yep, it definitely pulled, that’s to be expected with that much weld in my experience!
    Did not line bore.
    Got out the big rosebud and some grade 8 all thread, hardened nuts and washers.
    Heated the ears up along the weld lines a dull red and pulled them back in alignment till the pin dropped through.
    Took three tries, but was much faster than setting up to bore.
    As well I feel it’s good for the welds to post heat them, I think it helps prevent cracks/brittleness.
     
  10. Batkom

    Batkom Well-Known Member

    Joined:
    Dec 24, 2017
    Messages:
    139
    Location:
    Idaho
    20EDD658-4146-45F2-BB5F-A23A84F2CA04.jpeg Top picture is after adding 3 1/4 inches.
    Bottom is before
    Not the same angle, so hard to see exact differences
    Hindsight- should have done 4 inches, that would have been perfect.
    Certainly will be ok though, and MUCH better than before! 43CD6EB4-E5DE-4D03-BB2A-2CB2AC275098.jpeg
     
    John Shipp likes this.
  11. Batkom

    Batkom Well-Known Member

    Joined:
    Dec 24, 2017
    Messages:
    139
    Location:
    Idaho
  12. John C.

    John C. Senior Member

    Joined:
    Jun 12, 2007
    Messages:
    6,400
    Occupation:
    Machinery & Equipment Appraiser
    Location:
    Northwest
    That is nice work.
     
  13. Batkom

    Batkom Well-Known Member

    Joined:
    Dec 24, 2017
    Messages:
    139
    Location:
    Idaho
    Thank you!
     
  14. Batkom

    Batkom Well-Known Member

    Joined:
    Dec 24, 2017
    Messages:
    139
    Location:
    Idaho
    1EF8BBFB-64DA-4530-824B-4C2ABB614B8A.png 685D5286-68EF-4995-9D99-B4BE38E3613E.jpeg Finally found a grapple with rigid rotator I could justify buying! Spent the last week getting it plumbed and the mounting bracket manufactured.
    So far really liking it for moving/stacking logs.
     
    Mother Deuce and John Shipp like this.
  15. JBGASH

    JBGASH Senior Member

    Joined:
    Jan 1, 2011
    Messages:
    748
    Occupation:
    Plumbing & Excavation Contractor / farmer
    Location:
    Missouri
    Nice job! I have a PC75UU that I would like to add a thumb too. How did you suppy hydraulics to the thumb you added?
     
  16. Batkom

    Batkom Well-Known Member

    Joined:
    Dec 24, 2017
    Messages:
    139
    Location:
    Idaho
    Thanks,
    Added a solenoid operated selector valve to divert the side shift oil to the thumb. Have a switch in the cab to select wich function.
    After I swapped booms I had that circuit available to run the grapple, and added another solenoid operated valve on the stick to divert oil to the rotator. This is activated with a momentary switch I installed in the top of the joy stick.
    After using for a few hours it’s pretty smooth and quick, I would I believe prefer a trigger type switch though on the front of the joy stick.
     
  17. Batkom

    Batkom Well-Known Member

    Joined:
    Dec 24, 2017
    Messages:
    139
    Location:
    Idaho
    Built a new stinger so I can move my gooseneck trailers around without having to go get the truck.
    Decided why not hang the logs in it from the grapple and limb right into the trailer, worked, but actually found it to be better just to set the log in the trailer, limb it n then remove the log.
    Works slick! C95FE385-B3AF-4DC8-9F2E-68172239D330.jpeg
     
    John C. and Mother Deuce like this.