Braze on repair on frame - any advice please?

Ringpeace
Ringpeace Posts: 105
edited March 2014 in Road beginners
Basically have a frame with braze on. This has got slightly damaged, not bent but the metal isn't smooth anymore and is a bit indented / pitted.

This keeps making the front mech move - as it isn't sitting correctly. Bar an expensive strip down, package, post to Argos cycles and get a new braze on fitted - does anyone have any ideas how to fix?

The frame won't accept a band on easily as it's a bit square. Was wondering if there were any kind of washers available to fit over the braze on so that the mech will clamp a smooth surface?

Apologies if in wrong place - just know that this gets traffic. Will look see if I can repost in a mechanic forum.

Thanks in advance for any advice or suggestions,

Cheers

Comments

  • desweller
    desweller Posts: 5,175
    Tighter screws?
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  • freezing77
    freezing77 Posts: 731
    As above.
  • Ringpeace
    Ringpeace Posts: 105
    Not sure you are getting what I am saying - will go and get a pic.

    There are no screws - only one bolt connecting the front mech to the braze on. That ain't holding as the actual braze on has got damaged and indented. Therefore the rounded washer to fit the mech to the braze on - is not gripping it properly - hence the slipping!
  • freezing77
    freezing77 Posts: 731
    How about a thin lead washer that will deform as you tighten it. Similar to what is used on porcelain loos to hold them to the wall.
  • Cranked
    Cranked Posts: 3
    How about something like this http://www.amazon.co.uk/Braze-Front-Der ... B003RLK1WQ
  • desweller
    desweller Posts: 5,175
    A bolt is a screw.

    The bracket is a slotted piece right? And there is a screw that clamps the derailleur to it with the aid of a nut.

    So tighten the screw up. I don't fully understand why the surface condition should be stopping it from working - a photo might help?
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  • freezing77
    freezing77 Posts: 731
    DesWeller wrote:
    A bolt is a screw.

    The bracket is a slotted piece right? And there is a screw that clamps the derailleur to it with the aid of a nut.

    So tighten the screw up. I don't fully understand why the surface condition should be stopping it from working - a photo might help?

    I am also having difficulty visualising the exact problem.
  • Ringpeace
    Ringpeace Posts: 105
    freezing77 wrote:
    How about a thin lead washer that will deform as you tighten it. Similar to what is used on porcelain loos to hold them to the wall.

    Thanks for the advice - had never even heard of these. It basically just needs to make the braze on flat and smooth as it was out the factory.

    ATM I have the mech a lot higher up - attached to the good piece of braze on. It's a triple so this affects some granny ring combos - but only ones that you'd never really use.

    It's just that I have spent a lot of money on the bike since new and it's annoying that such a little thing could cause so much grief.
  • Initialised
    Initialised Posts: 3,047
    Chances are the nut has been overtightened in the wrong position leaving a gouge, so when it's fitted in the right place it'll shift back into the existing gouge. So a washer (as above) could help stop it going into the gouge or you could use a locking washer to reduce the change it'll move at the cost of more damage to the mount point.
    I used to just ride my bike to work but now I find myself going out looking for bigger and bigger hills.
  • Ringpeace
    Ringpeace Posts: 105
    Initialised wrote:
    Chances are the nut has been overtightened in the wrong position leaving a gouge, so when it's fitted in the right place it'll shift back into the existing gouge. So a washer (as above) could help stop it going into the gouge or you could use a locking washer to reduce the change it'll move at the cost of more damage to the mount point.

    It hasn't or shouldn't have been over tightened. I think the problem stems back to being hit my a car back in September and thinking all is well visually. I was off the bike for over 3 months - the fact that I am back on it has made me realise there were more problems than initially thought.

    What I suspect has happened is the impact has jammed the mech bolt into the braze on and damaged it. It's not something that you'd initaily notice. I was looking for frame damage. It's only because I am riding the bike again and kept noticing the chain rub.

    Hopefully the pics will do more explaining than I can! As you can see the mech is a lot higher than would be normal - as that is the only part of the braze on that is smooth. Some kind of plate is what I need to fix over the braze on - preferably with "teeth" on the back so it really grips.

    a267uq.jpgeah2kl.jpg
  • Ringpeace
    Ringpeace Posts: 105
    Cranked wrote:
    How about something like this http://www.amazon.co.uk/Braze-Front-Der ... B003RLK1WQ

    Thanks - this looks like it might do the job. Problem is my LBS have amazingly never seen this problem - and are just suggesting sending to Argos to get a new braze on fitted.

    It would cost me more than the frame is worth! Something like that may do the job well. I'm just not sure - hence the question!

    Cheers
  • desweller
    desweller Posts: 5,175
    Ah OK. So you've got some burrs / bruising / high spots on the bracket clamping faces?

    I'd probably just file it back and then touch up with some black paint.
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  • Ringpeace
    Ringpeace Posts: 105
    DesWeller wrote:
    Ah OK. So you've got some burrs / bruising / high spots on the bracket clamping faces?

    I'd probably just file it back and then touch up with some black paint.

    Thanks - that has been tabled as a possible solution but more with a weld to bring it back level. I don't think the pic shows quite how deep it is.

    The other poster that linked to the part on Amazon - that's the sort of thing I need but don't know it's name or whether it is even going to fit.

    Common sense that all it needs is a replacement part to sit on top of it and make the surface flush. In theory there should be no need to have to go to the hassle and expense of fitting a whole new braze on.

    Whether I can find that solution with the wisdom of the internet is a different matter!

    If I was anyway handy or new someone handy then I am sure they could fettle up a little plate / shim. Unfortunately I'm not and don't!
  • desweller
    desweller Posts: 5,175
    I'd go with the soft metal washer in that case. But I'd still probably just tighten the screw up more - you can go pretty damn tight on those.
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  • markos1963
    markos1963 Posts: 3,724
    If you don't mind me saying your mech looks to be sitting too high above the chain wheel. This is obvious as the mech bolt is sitting right at the top of its slot. You only need about 1-2mm clearance between the top of the chain wheel and the bottom of the mech cage. With this in mind would lowering the mech on the braze on put it into a better position for tightening saving you the hassle of a lot of remedial work?
    Norfolk, who nicked all the hills?

    http://farm4.static.flickr.com/3013/243 ... 8d.jpg?v=0
    http://img362.imageshack.us/my.php?imag ... 076tl5.jpg
    http://img216.imageshack.us/img216/3407 ... e001af.jpg
  • Ringpeace
    Ringpeace Posts: 105
    markos1963 wrote:
    If you don't mind me saying your mech looks to be sitting too high above the chain wheel. This is obvious as the mech bolt is sitting right at the top of its slot. You only need about 1-2mm clearance between the top of the chain wheel and the bottom of the mech cage. With this in mind would lowering the mech on the braze on put it into a better position for tightening saving you the hassle of a lot of remedial work?

    I don't mind you saying at all. It is too high - the only part of the braze on that is sound and it wouldn't move on. It's a "fix" to make the bike rideable.

    Middle and Big ring are fine in this position. Granny gear is useable with certain cogs but not extreme. Luckily my fitness has somehow improved and I can get away with what I have. Probably due to me swapping the cassette from a 23 to a 26 that I am now running.

    Apologies if I have or haven't explained how this got damaged in the 1st place. It has really annoyed me because this is my 1st road bike, spent a load of money on it, looked after it and some idiot not indicating has caused this damage. That wasn't apparent - until I started riding the bike again.

    With hindsight am wishing I went to one of these claim lawyers from the start - but I just wanted my bike fixed and took the accident "on the wrist". 6 months later and knackered wrist and bike am regretting being quite so easy going and fair.

    The bike has always been kept in excellent condition in case I wanted to sell it. I simply couldn't and wouldn't sell it due to this fact. It's pretty annoying!

    Thanks for the advice anyway. I don't even WANT to sell it - it's more the fact that I can't! FFS - LOL

    Cheers

    BTW - in the pics it looks pretty filthy - it is never kept like that - this is just a pic of the bodge we have managed and it was wet. That crap wouldn't generally be on it!
  • slowbike
    slowbike Posts: 8,498
    One option may be to cut a plate to go over the top, bend and having cleaned the braze on down to the metal - use metal glue (2pack) to glue the plate in place - the plate then effectively being a big washer/part of the brazeon


    All you need is a source of some thin aluminium - an old camping pan may be thin enough ...

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