Press fit clearance?

  1. Dcal

    Dcal Forum Supporter

    Messages:
    2,351
    Location:
    Antrim Northern Ireland
    They both come with longitudinal front torsion bars (like a Minor or Marina) but a lot are converted to coil overs.
     
  2. mtt.tr

    mtt.tr Member

    Messages:
    4,012
    Essex England

    Was thinking, if that's under the minor diameter it will deform the knurl and deform the sleeve but i get what are saying

    I assume its just to give location as opposed to holding. i would be somewhat suprised if this required 50t to deform the steel id even suggest hes created a new special alloy


    Here is an old bookmark which I've used in the past with success
    https://www.tribology-abc.com/sub23.htm
     
    Last edited: May 8, 2020
  3. daleyd

    daleyd Member

    Messages:
    7,099
    Location:
    Wrexham, North Wales
    For info here are the Zeus tables - though it’s same info as already posted...

    2B2E4030-9D10-431B-989E-F0DCBBB86C24.jpeg 449DF925-B565-43E8-AA8C-ECB7286094D7.jpeg
     
    mm289 likes this.
  4. Seadog

    Seadog Forum Supporter

    Messages:
    6,968
    Location:
    NE London - UK
    I often flick past those pages in my Zeus and wonder "What's that all about then?" :D
     
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  5. Morrisman

    Morrisman Forum Supporter

    Messages:
    2,697
    Location:
    Staffordshire, England
    Exact size per size is a hammer fit at best, interference just makes it harder.

    With that spline involved I'd give it 5 thou interference as the splines will either distort, or cut, when it is pressed together.

    And I'd not be surprised if that is the actual idea behind the splines: less precision needed when machining the hole, equates to less cost to manufacture.
     
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  6. Wallace

    Wallace Member

    Messages:
    7,511
    Location:
    Staines, Middlesex, England.
    That was covered in great detail every ruddy year at college, I would assume this position every time I heard "Selected ISO Fits, Hole Basis".:mad:

    head.jpg
     
  7. addjunkie

    addjunkie Member

    Messages:
    6,467
    Location:
    Northumberland. Reet oot in the sticks
    I felt the same when I was an apprentice, 25 years before I used it.....big fan of freezer and oven though, makes far less ooomph to push them together.
     
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  8. pressbrake1

    pressbrake1 Forum Supporter

    Messages:
    2,880
    essex england
    I’m not suggesting his application would take 50t to assemble.
    A thou interference fit on softer materials can cause broaching and galling on assembly and general dreadfulness.
    On hardish materials with good finish and the ‘female’ part to be substantial enough to have good wall thickness around the hole so not to stretch and yields great pressures to assemble can result with just a thou oversized.
    This isn’t wood , wood butcher :D
     
  9. mtt.tr

    mtt.tr Member

    Messages:
    4,012
    Essex England
    I would take the knurls purpose being to gall the part on assembly, thats the only use ive seen for knurled ball joints mostly on knckered 4x4s once the existing hole is errm for lack of polite word different


    I dont like too tighter wood personally, you need a cooper for that. ;)
     
  10. minimutly Member

    Messages:
    1,486
    Location:
    Pembrokeshire Wales
    That's not a knurl....
     
  11. mtt.tr

    mtt.tr Member

    Messages:
    4,012
    Essex England
    Be helpful, what would you call it?
     
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  12. rory1

    rory1 Member

    Messages:
    1,183
    Location:
    Macclesfield
    It most certainly is . It’s a straight knurl
     
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  13. Wallace

    Wallace Member

    Messages:
    7,511
    Location:
    Staines, Middlesex, England.
    It looks to me that the stud is used to keep the the joint in the wishbone and the knurl as an interference fit stops rotation. Is this a coilover conversion? The GM ones are an interference fit from under the wishbone with no mechanical fixing as they have the vehicle weight acting on the arm against the spring.
     
  14. minimutly Member

    Messages:
    1,486
    Location:
    Pembrokeshire Wales
    I realised that after I posted it - but in my head the point I was making was it wasn't a knurl in the classic sense.
    The straight "knurl" is harder than the metal its going into, so forms it as its being pressed in, hence the accepted interference fits don't apply.
     
  15. slim_boy_fat

    slim_boy_fat Forum Supporter

    Splined? :dontknow:
     
  16. grim_d

    grim_d Unlikeable idiot.

    Messages:
    3,093
    Location:
    Scotland - Ayrshire
    It's not splined, splines locate in one another and transmit drive.

    IMO on that part the knurl serves two purposes aside from anti-rotation, it reduces the surface area of the interference making it easier to press the part in on-vehicle.

    It's 2nd purpose is to allow for a difference in tolerance in the mating part due to corrosion or repeated fittings.
     
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  17. 8ob

    8ob Forum Supporter

    Messages:
    6,680
    Location:
    moscow on thames
    I got curious about this and had a google about, them Dang Merikuns who build a lot racers with these joints use a 10 thou interference fit. They refer to it as a "crush fit" trust them :rolleyes:

    Bob
     
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  18. nickk Forum Supporter

    Messages:
    2,705
    Location:
    Hay-on-wye
    Them damn Mericans like to use their own language,saves them having to learn proper English,think trump.
     
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  19. slim_boy_fat

    slim_boy_fat Forum Supporter

    Noooo! :laughing:
     
  20. mtt.tr

    mtt.tr Member

    Messages:
    4,012
    Essex England
    I know these knurled ones for when wishbones hole is knackered.
     
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