Rim failed during wheel build

matudavey
matudavey Posts: 108
edited April 2015 in Workshop
I was building a wheel for a friend:
PlanetX Retro rim
Tiagra hubs
32 x DT Competition spokes
brass nipples and washers

Following the WheelPro instructions (this is the 16th wheel I've built, so thought I was getting the hang of it!) and during the stressing of the wheel, the rim suddenly 'pringled' and came apart at the pinned joint.

http://i.imgur.com/UGcfv5n.jpg
http://i.imgur.com/hpzKAum.jpg

I assume I pushed too hard during stressing (pushing down on the rim with the hub on a block)
Could this have been due to too little tension in the spokes not supporting the wheel properly and allowing too much relative lateral movement?

I would have thought that higher spoke tension would only hold the rim join in a more stable position, and therefore excessive tension couldn't be the cause.

Has anyone had experience or have knowledge of the common cause of this type of failure?
I assume this is user error rather than a manufacturing fault? (these rims are really cheap!)
I build a front wheel with this rim without issue... should I be worried?
Would I be an idiot to try and build the rear again with the same (new) rim?

Comments

  • drlodge
    drlodge Posts: 4,826
    Wow. That rim looks pretty cheap to me, like it just came apart. What tension were the spokes?
    WyndyMilla Massive Attack | Rourke 953 | Condor Italia 531 Pro | Boardman CX Pro | DT Swiss RR440 Tubeless Wheels
    Find me on Strava
  • drlodge
    drlodge Posts: 4,826
    Its a £15 rim so confirmed it is cheap. And there is one comment on Planet-x web site including the words "Rim joint not terribly good". Bin it and buy a decent rim?
    WyndyMilla Massive Attack | Rourke 953 | Condor Italia 531 Pro | Boardman CX Pro | DT Swiss RR440 Tubeless Wheels
    Find me on Strava
  • ugo.santalucia
    ugo.santalucia Posts: 28,312
    Don't worry I did the same with an old Ambrosio Elite... to be honest these NOS rims are pretty rubbish, which is the reason in the days they were built with 36 spokes and paltry tension
    left the forum March 2023
  • matudavey
    matudavey Posts: 108
    The problem is I'm building them for a friend. The front seems fine, although it was a struggle to get true.
    I'd ideally not exceed the £100/pair price I'd quoted.

    His criteria were:
    shiny
    cheap
    for 5 miles a day to and from the station
    Any suggestions for a different rim that wouldn't look out of place paired with the front?

    Tension was reasonable on the drive side but fairly low on the NDS.
    I assume the front went well as the even tension keeps it in a nice strong position, and as long as tensions are even, extra tension just makes the pinned joint stronger?
  • arlowood
    arlowood Posts: 2,561
    matudavey wrote:
    Any suggestions for a different rim that wouldn't look out of place paired with the front?


    This is a possibility (the silver option) and not much more expensive

    http://www.chainreactioncycles.com/mavi ... lsrc=aw.ds

    You could also go for an Open Pro in silver but that would be more money again - about £34
  • drlodge
    drlodge Posts: 4,826
    £100 for a pair of wheels is dirt cheap, I'd expect to pay nearly that just for the spokes and build.
    WyndyMilla Massive Attack | Rourke 953 | Condor Italia 531 Pro | Boardman CX Pro | DT Swiss RR440 Tubeless Wheels
    Find me on Strava
  • Bobbinogs
    Bobbinogs Posts: 4,841
    Maybe this is one of those jobs that you learn from, next time when someone says they want a pair of handbuilts for £100 you can say "It can't be done, get some R501's". :)
  • matudavey
    matudavey Posts: 108
    He couldn't find any factory shiny silver wheelsets cheap enough!
    .. and I was keen to offer, to increase my wheel building experience. At £100 I thought it was pretty low risk if i messed it up. I'm not trying to make money from it, only charging him for parts really.

    I know re-using spokes isn't a good plan, but I assume that's from a fatigue life point of view?
    If they've only been laced and tensioned, then I'd have thought they're reusable?

    If the same rim was used, do you think this would just repeat itself, or could I alter my building process to mitigate the risk of failure?

    What rims are the next tier up?
  • keef66
    keef66 Posts: 13,123
    "He couldn't find any factory shiny silver wheelsets cheap enough!"

    You could've spent £70 on a set of R501's and quickly polished them up to a nice shine?
  • Monty Dog
    Monty Dog Posts: 20,614
    No worries re-using spokes - I have some 40 year old spokes - as long as they've not been over-stressed they should last indefinitely and nipples should be good to go as the wheels haven't been ridden and therefore not subject to cyclic loads.
    Make mine an Italian, with Campagnolo on the side..
  • matudavey
    matudavey Posts: 108
    edited April 2015
    arlowood wrote:
    matudavey wrote:
    Any suggestions for a different rim that wouldn't look out of place paired with the front?


    This is a possibility (the silver option) and not much more expensive

    http://www.chainreactioncycles.com/mavi ... lsrc=aw.ds

    You could also go for an Open Pro in silver but that would be more money again - about £34

    Thanks, that's perfect - similar ERD too! Annoying I didn't consider that before!

    Do I have any chance of getting the broken one refunded from PX... fit for purpose or user error?
  • matudavey
    matudavey Posts: 108
    On the plus side, breaking that rim gave me the chance to finish these in time for the weekend!

    http://i.imgur.com/5DVytL4.jpg
  • ugo.santalucia
    ugo.santalucia Posts: 28,312
    matudavey wrote:

    Do I have any chance of getting the broken one refunded from PX...

    Definitely...
    left the forum March 2023
  • drlodge
    drlodge Posts: 4,826
    No harm in asking them for a replacement rim, you've nothing to lose.
    WyndyMilla Massive Attack | Rourke 953 | Condor Italia 531 Pro | Boardman CX Pro | DT Swiss RR440 Tubeless Wheels
    Find me on Strava
  • imatfaal
    imatfaal Posts: 2,716
    matudavey wrote:
    arlowood wrote:
    matudavey wrote:
    Any suggestions for a different rim that wouldn't look out of place paired with the front?


    This is a possibility (the silver option) and not much more expensive

    http://www.chainreactioncycles.com/mavi ... lsrc=aw.ds

    You could also go for an Open Pro in silver but that would be more money again - about £34

    Thanks, that's perfect - similar ERD too! Annoying I didn't consider that before!

    Do I have any chance of getting the broken one refunded from PX... fit for purpose or user error?

    Go for full refund - it is a wheel rim and can be expected to be built up to a wheel. If it is in within 6mo of purchase and it has failed in normal usage (which I would say it has) then SOGA79 says that the burden of proof is upon them to show that it wasn't defective upon sale.

    http://www.legislation.gov.uk/ukpga/1979/54

    you want 14 2B and 48A from memory. They WILL tell you no to start with - but emails cost nothing and a bit of badgering will see you win
  • JayKosta
    JayKosta Posts: 635
    matudavey wrote:
    ...
    I assume I pushed too hard during stressing (pushing down on the rim with the hub on a block)
    Could this have been due to too little tension in the spokes not supporting the wheel properly and allowing too much relative lateral movement?
    ...
    Perhaps a defect with the rim, but also perhaps too much rim movement during the stressing. Does your wheel building book suggest a 'distance' to move the rim, or 'just enough' to hear a few spokes losing tension?

    Jay Kosta
    Endwell NY USA
  • keezx
    keezx Posts: 1,322
    Cause of the failure is most likeley the single wall construction of the rim, these do not allow much tension.
    You cannot build these rims like double wall , much stiffer ones.

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