galvanic welding barrel adjuster

[Nebulous]

I've got some weird steel on metal thing going on with my downtube barrel adjuster for my rear derailleur. The cable was sticking, and the metal ferrule was stuck in the adjuster. On trying to remove it I managed to break the adjuster.
I managed to find these, but realised that the old one broke off just below the cap, so the threaded bit is still in the hole.
The last thing I want now is to make things worse and break the frame. I need some kind of fix to fit a ferrule in the hole and thread the cable through it. I don't need the barrel adjuster. I tend to use the one at the rear mech when indexing.
What are my options - get someone to drill out the threaded (steel?) bit in the alloy lug on the frame?

Thanks

 

[sidevalve]

You have several choices. Drill out the remains to the thread base then run a tap through [may not need the tap, the remains of the thread may just "peel" out] and all is as was. Drill part way the width of a cable ferrule and simply fit a cable [you lose the adjustment but if you don't use it anyway then no problem]. Try a stud extractor, if you can find one small enough.
Either way you are lucky as the hole in the middle will form a guide for the drill and the chances of going off centre [with care and a good sharp drill] are small.

 

[actonblue]

The barrel adjuster assembly is attached to a braze on boss on the downtube so it unscrews and you van buy a whole new assembly http://www.sjscycles.co.uk/shimano-alloy-braze-on-down-tube-cable-stops-with-barrel-adjusters-prod5511/

 

[PpPete]

The barrel adjuster assembly is attached to a braze on boss on the downtube so it unscrews and you van buy a whole new assembly http://www.sjscycles.co.uk/shimano-alloy-braze-on-down-tube-cable-stops-with-barrel-adjusters-prod5511/

Not suitable for many modern bikes. From the OP's description I don't thing they'd help in his case - although I could be wrong.

 

[actonblue]

I have two bikes that I bought in the last two years and they both have these. How modern do you want?

 

[gbb]

Had the same on my Bianchi, the bosses are welded to the frame, not as Actons suggestion.
Because they're so close to the frame. getting a drill long enough is difficult....the headtube stops you getting anywhere near with a drill chuck. The fix (my fix anyway) requires some workshop equipment.
I went to Toolfix or similar and got a 150mm hexagon extension and some hexagon drive drill bits, particually a 4mm. The drills came in a set of three, 3,4 and 5mm i think, they only cost about £3.
The heagon extension in the drill allows you to drill out the old barrell adjuster.
Then you need a 5 mm tap, but you face the same dilemma getting it near the boss. I used a grinder to shave a tiny bit off the square shank of the tap so it sat snugly in the hexagon extension.
Its a faff, but i have the neccessary equipment. Retapping was easy then, job done.

 

[Nebulous]

Thanks very much gbb and sidevalve that was very helpful.

I got off early today and tried to get going. I got the hexagon extension from screwfix and some hex drill bits from B & Q and I couldn't believe how easy it was to drill out. I've ordered some new barrel adjusters from Edinburgh Bike and need to wait for them to arrive, but I'm hoping I won't need to retap it, particularly given I don't want to use the adjuster anyway.

 

[Nebulous]

Well I got my new barrel adjuster- screwed it in from the back of the mount and the remains of the old one I had drilled through popped out. I then managed to screw it in from the top, after removing the spring and it has fitted fine. I have no intention of removing it again.