Oops. Stripped the threads on my derailleur hanger
03-15-12, 02:24 AM
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Oops. Stripped the threads on my derailleur hanger
So. I don't have a replaceable hanger for my derailleur. I did manage to strip the threads though. How can I fix this
03-15-12, 05:43 AM
#2
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Not the end of the world. There are lots of options, here are 5 of them listed in the order that I consider from best/practical to least desirable.
Option 1: There is an insert called a "dropout saver" that will slide into the stripped hole in the hanger that has a flange on one end and internal threads that the derailleur threads into. The flange keep the insert from pulling through the hanger and the derailleur keeps it all snug. https://www.loosescrews.com/index.cgi...d=407071221192
Option 2: Find a shop who has or order online a helicoil kit with the proper outside diameter and internal threads.
Option 3: Have a welder/brazer or frame builder add metal to the stripped hanger and then have it retapped to accept a derailleur.
Option 4: Buy a claw type replacement hanger that uses the dropout to hold it in place but has a hole to thread a rear derailleur into.
Option 5: Replace your derailleur with one that has the claw type hanger integrated into it. These tend to be rather low quality units.
-j
Option 1: There is an insert called a "dropout saver" that will slide into the stripped hole in the hanger that has a flange on one end and internal threads that the derailleur threads into. The flange keep the insert from pulling through the hanger and the derailleur keeps it all snug. https://www.loosescrews.com/index.cgi...d=407071221192
Option 2: Find a shop who has or order online a helicoil kit with the proper outside diameter and internal threads.
Option 3: Have a welder/brazer or frame builder add metal to the stripped hanger and then have it retapped to accept a derailleur.
Option 4: Buy a claw type replacement hanger that uses the dropout to hold it in place but has a hole to thread a rear derailleur into.
Option 5: Replace your derailleur with one that has the claw type hanger integrated into it. These tend to be rather low quality units.
-j
Last edited by Zef; 03-15-12 at 05:48 AM.
03-15-12, 06:13 AM
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Greenfieldja laid out all your options.
Of those the best is to use a helicoil insert. Since the tools required cost about $60.00, your cheapest option is to let a decent shop do this for you.
The second best is a nut type insert, which you can insert yourself. The two drawbacks of the nuts are that they require a larger hole to be drilled into the hanger than a Helicoil would, and that the flange of the nut is in the back where there's already minimal clearance to the chain.
Note that you can use a Helicoil now, while still having the option of the nut later, but not the other way around.
All the other options are for more desperate situations and I'd pass on them for now.
Of those the best is to use a helicoil insert. Since the tools required cost about $60.00, your cheapest option is to let a decent shop do this for you.
The second best is a nut type insert, which you can insert yourself. The two drawbacks of the nuts are that they require a larger hole to be drilled into the hanger than a Helicoil would, and that the flange of the nut is in the back where there's already minimal clearance to the chain.
Note that you can use a Helicoil now, while still having the option of the nut later, but not the other way around.
All the other options are for more desperate situations and I'd pass on them for now.
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An ounce of diagnosis is worth a pound of cure.
Just because I'm tired of arguing, doesn't mean you're right.
“One accurate measurement is worth a thousand expert opinions” - Adm Grace Murray Hopper - USN
WARNING, I'm from New York. Thin skinned people should maintain safe distance.
03-15-12, 11:08 AM
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The dropout saver insets just need a wrench to hold the hex on it's flange,
while you tighten the derailleur mounting bolt.
As FB suggests, tapered hand reamer will remove additional metal
to get a very good fit ..
while you tighten the derailleur mounting bolt.
As FB suggests, tapered hand reamer will remove additional metal
to get a very good fit ..
03-15-12, 11:19 AM
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I agree I don't understand where the $60 worth of tools comes from for that LooseScrews insert.
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03-15-12, 11:36 AM
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No, FB is saying that the tools used to properly drill/tap/insert a Helicoil insert cost around 60 dollars to get it done right. I have made-do with not much more than a colbalt drill and a cheap tap but that isn't the best way to install a Helicoil.
03-15-12, 12:31 PM
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Helicoil needs a oversize thread cutting tap, and a insertion tool
to screw in the diamond shaped spring steel coil ..
to screw in the diamond shaped spring steel coil ..
03-15-12, 02:51 PM
#8
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Which is available as a kit from Helicoil. Now it's been some time since I bought a Helicoil kit, but I don't think I paid $60 for it.......probably half that amount.
03-15-12, 04:24 PM
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The trend to breakaway replaceable hangers, will eventually make this type of repair obsolete, unfortunately some of those replacement hangers cost $25.00 or more (at least it's cheaper than a frame).
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An ounce of diagnosis is worth a pound of cure.
Just because I'm tired of arguing, doesn't mean you're right.
“One accurate measurement is worth a thousand expert opinions” - Adm Grace Murray Hopper - USN
WARNING, I'm from New York. Thin skinned people should maintain safe distance.
FB
Chain-L site
An ounce of diagnosis is worth a pound of cure.
Just because I'm tired of arguing, doesn't mean you're right.
“One accurate measurement is worth a thousand expert opinions” - Adm Grace Murray Hopper - USN
WARNING, I'm from New York. Thin skinned people should maintain safe distance.
