Star Fangled Nut installation?

redddraggon
redddraggon Posts: 10,862
edited April 2008 in Workshop
I know it's got to be set at a certain depth from the stack height/length of steerer, but is there anyway of successfully installing one with the specific tool?
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Comments

  • Smokin Joe
    Smokin Joe Posts: 2,706
    The only tool I used was a large pair of pliers to bend the tabs back till it would tap in easily.
  • Gussio
    Gussio Posts: 2,452
    Have done this job with a piece of dowling and a rubber mallet, which has worked fine (I got away with it, anyway). Last time I installed a new pair of forks, after measuring and cutting the steerer I took them to the LBS who were kind enough to install the crown race and the star fangled nut free of charge (I had bought the forks from them though).
  • Mystique
    Mystique Posts: 342
    Last time I used a socket which just fitted inside the steerer, then gently tapped it down using a rubber mallet & extension bar - certainly seemed to keep the washer on the straight & narrow.
  • aracer
    aracer Posts: 1,649
    I now install by using a threaded bar a nut and some washers and pulling it into place (in much the same way as headset installation). Far easier to keep it straight than when using a percussive adjustment tool.
  • robbarker
    robbarker Posts: 1,367
    TBH I've always found it a piece of p*ss with a Park TNS1, a big hammer and mark one eyeball. Don't bend the tabs back, it won't grip as well.
  • dennisn
    dennisn Posts: 10,601
    robbarker wrote:
    TBH I've always found it a piece of p*ss with a Park TNS1, a big hammer and mark one eyeball. Don't bend the tabs back, it won't grip as well.

    I agree. The Park tool puts it in very easily and to the right depth. Assuming you have your steerer tube cut to the right length. Where the Star nut sets has nothing to do with stack height. It only deals with the top of the steerer tube. If you recut your steerer
    to a shorter length you need to reset the star nut with the proper tool(Park). This tool will put the nut in at a set distance from the top of your steer tube. It's an inch or so, give or take a bit.

    Dennis Noward
  • meagain
    meagain Posts: 2,331
    Mystique wrote:
    Last time I used a socket which just fitted inside the steerer, then gently tapped it down using a rubber mallet & extension bar - certainly seemed to keep the washer on the straight & narrow.

    Ditto. Done a few this way - no problem (tho' patience helps!).
    d.j.
    "Cancel my subscription to the resurrection."
  • redddraggon
    redddraggon Posts: 10,862
    dennisn wrote:
    Where the Star nut sets has nothing to do with stack height. It only deals with the top of the steerer tube.

    The stack (with stem) height should be about 3mm higher than the top of the steerer tube, and the star nut needs to be a certain distance below that again.
    I like bikes...

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  • dennisn
    dennisn Posts: 10,601
    redddraggon wrote:
    dennisn wrote:
    Where the Star nut sets has nothing to do with stack height. It only deals with the top of the steerer tube.

    The stack (with stem) height should be about 3mm higher than the top of the steerer tube, and the star nut needs to be a certain distance below that again.

    I,m thinking that the star nut tool simlpy puts the nut in at a given distance from the top of
    the steerer tube. You drive the nut in until the tool stops at the steerer top. Then unscrew
    the tool and, bingo, you are there. Star nut set. Your cap fixing bolt will extend a liitle bit
    past the nut when you start tighting things up. I agree that you need to cut the steerer
    slightly below the last spacer or stem so that you can snug up the fork and bearings with the
    fixing bolt and top cap. Whew, did I say all that???

    Dennis Noward
  • Barrie_G
    Barrie_G Posts: 479
    How about a removable one such as THIS I've used one in the past on a mountain bike and had no problems, after all it's only there to tension the headset etc until you tighten the stem onto the steerer.
  • Smokin Joe
    Smokin Joe Posts: 2,706
    robbarker wrote:
    TBH I've always found it a piece of p*ss with a Park TNS1, a big hammer and mark one eyeball. Don't bend the tabs back, it won't grip as well.
    I bet you couldn't pull the star nut out of my steerer. They only need the lightest of pressure to grip on the bore of the tube.
  • robbarker
    robbarker Posts: 1,367
    It has to stay put in both directions in the face of a lot of vibration to maintain a constant preload on the headset bearings. It's designed the way it is for a reason and setting it squarely and to the right depth is not a problem with the right tool.

    Using a socket and a stem as an alignment guide also works well, provided you mark the 15mm setting depth on the socket, although I wouldn't personally abuse my expensive sockets like that!
  • Smokin Joe
    Smokin Joe Posts: 2,706
    The star nut does not have to stay put at all, once you have torqued up to the correct preload and tightened the stem the load on the bearings will remain the same even if the star nut disappears.

    In any case, it cannot drop down the steerer because the bolt is forcing it up. I don't see how it can be mis-aligned either, once the second teir of fangs is in the steerer it will self align.
  • dennisn
    dennisn Posts: 10,601
    Smokin Joe wrote:
    The star nut does not have to stay put at all, once you have torqued up to the correct preload and tightened the stem the load on the bearings will remain the same even if the star nut disappears.

    In any case, it cannot drop down the steerer because the bolt is forcing it up. I don't see how it can be mis-aligned either, once the second teir of fangs is in the steerer it will self align.

    I have heard of weight weenies actually removing the top cap. screw, and star nut after
    things are all set up. This helps them go at least 30% faster.

    Dennis Noward
  • aracer
    aracer Posts: 1,649
    31% surely, dennis. Or maybe 31.1%.
  • robbarker
    robbarker Posts: 1,367
    Forgot where I was - you're right for road systems, of course. (an you tell I'd just woken up after nights when i posted that?) The last time I had this conversation was on an MTB forum where stems are often left looser so that no damage is done in an off. Debateable point even tnen but they taught it on my wrench monkey course so it must be true...
  • dennisn
    dennisn Posts: 10,601
    aracer wrote:
    31% surely, dennis. Or maybe 31.1%.


    My testing wasn't under really ideal clinical conditions. Your results may vary.

    Dennis Noward
  • normanp
    normanp Posts: 279
    edited April 2008
    PS to thread: the star washer is not recommended for carbon steerers
  • Steve I
    Steve I Posts: 428
    Stems left loose to prevent damage in an off. Er, not on my mountain bike. I'll go for the crash damage every time, safe in the knowledge that my front wheel will go where I point it.

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