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Ferrule sizing?

plug1nplug1n Posts: 204
edited January 2008 in Workshop
I'm transferring an old friction rear derailleur from one frame to another.

The ferrule that stops the cable loop on my old frame had a 4.5mm section that fitted in the cable stop under the rear stay.

But on the ~96 Frondriest steel frame I am trying to build up, this stop is only ~4mm, so my old ferrule will not fit.

Is this normal? I cannot spot any 3.5 or 4mm ferrules on the web.

Any suggestions for a work around?

Looks like a trip to the LBS tomorrow, I'm off the road until I have something working




  • Smokin JoeSmokin Joe Posts: 5,669
    With friction you can get away without the ferrule. It won't matter if there is a slight bit of compression on the cable when you change gear.
  • maddog 2maddog 2 Posts: 8,114
    standard shimano ferrules are pretty narrow. Have you tried one of these?

    if it's going to be a long term problem then you could drill the cable stop out to a wider fitting, using a dremel or long drill bit.
    Facts are meaningless, you can use facts to prove anything that's remotely true! - Homer
  • alfabluealfablue Posts: 8,497
    I have ferrules that are stepped, so the part that goes in the lug is the same diameter as the cable outer - they are branded Avid and Jagwire - probably came from cable sets. I reckon a good LBS should sort you out.

    They look like this:


    There are some on ebay, they are 5.5mm, but that relates to the thicker part I presume. Unfortunately I can't get my calliper on the narrow part of my ferrules without disconnecting my cables, so I can't confirm the smaller diameter.

    Worst comes to worst, I don't think there would be much of an issue running without ferrules as the outers will probably be a tight fit in the lugs, maybe some slight penalty in weatherproofing (though I recommend fully sealed cables, like Mudlovers - they have been truly "fit and forget" on my commuter for the last 18 months).
  • alfabluealfablue Posts: 8,497
    Okay, I retract most of the above - I have just measured my ferrules, they are 5.5mm, stepping down to 5mm, all of my outers are also 5mm. Are you sure of your measurements Plug1? Sorry to question that, just it sounds like you would have trouble even getting standard outers to fit in a 4mm lug.
  • plug1nplug1n Posts: 204
    Thanks for the comments.

    The ferrule I have was like alfablue's picture with the smaller diameter at 4.5mm. The stop is no more than 4mm (too small to fit my micrometer inside!)

    In the end, I took a standard ferrule, drilled out the end to 4mm, stripped about 6mm of the cover off.

    I then applied epoxy resin to the cable cover and slipped the drilled out ferrule up, and epoxied the exposed core. Also crimped the ferrule & left to harden.

    Seemed OK on a 25 mile test ride.

    Ugly if you look closely but will do while I find something better.
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