Remedying crossthreading?

Sometimes it can be as easy as threading the bolt in from the backside. If the bolt material is
stronger than the drop-out material this can sometimes "re-tap" it.

"Mikael Seierup" <[email hidden]> wrote in message -"]news:[email hidden]-
berlin.de...

Quoted message said:

Due to paint I munged the first few mm of the thread for the rear

derailleur.

Quoted message said:

Threaded hole on the frame I mean. Any way to correct it?

/Mikael

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In article <[email hidden]>, [email hidden] says...

Quoted message said:

Due to paint I munged the first few mm of the thread for the rear derailleur. Threaded hole on the
frame I mean. Any way to correct it?

If you can't re-tap the threads using Bryan's suggestion, There are inserts that can be fitted
into the old hole. I think the process is to drill out the derailleur hole. press in a derailleur
sized insert.

--

Cletus D. Lee Bacchetta Giro Lightning Voyager clee.orgclee.orgOpen ↗
- Bellaire, TX USA -

"Cletus Lee" skrev...

Quoted message said:

If you can't re-tap the threads using Bryan's suggestion, There are inserts that can be fitted

into

Quoted message said:

the old hole. I think the process is to drill out the derailleur hole. press in a derailleur
sized insert.

For now I'll let the LBS worry about it, but if he fails I'll try the insert. Thanks. The other
side approach didn't work alas. Just typical it happens five days before someones hopefully
buying it. :-)

/Mikael

In article <[email hidden]>, Mikael Seierup says...

Quoted message said:

"Cletus Lee" skrev...

Quoted message said:

If you can't re-tap the threads using Bryan's suggestion, There are inserts that can be fitted

into

Quoted message said:

the old hole. I think the process is to drill out the derailleur hole. press in a derailleur
sized insert.

For now I'll let the LBS worry about it, but if he fails I'll try the insert. Thanks. The other
side approach didn't work alas. Just typical it happens five days before someones hopefully
buying it. :-)

It may not be worth buying for just this one instance, but what you need is a 10 mm by 1 mm metric
thread chaser (or tap) for the derailleur hanger (about $5 at www.biketoolssetc.com). I have bent
the derailleur hanger on a number of bikes, so I keep a derailleur hanger tool and a thread chaser
in my shop. Your LBS will have the chaser.

Steve Christensen Midland, MI

Mikey,

Best way: buy a tap with the correct thread. run it through the hole from the other end.

Cheapie sometmes works way (Don't quote me, I'll deny it!) Run a bolt with the correct thread thru
from the other side. If that doesn't work, sometimes, you can grind a flat onto the thread and use
that as a one time tap.

Good Luck,

Tom "Mikael Seierup" <[email hidden]> wrote in message -"]news:[email hidden]-
berlin.de...

Quoted message said:

Due to paint I munged the first few mm of the thread for the rear

derailleur.

Quoted message said:

Threaded hole on the frame I mean. Any way to correct it?

/Mikael

"Steve Christensen" skrev

Quoted message said:

It may not be worth buying for just this one instance, but what you need is a 10 mm by 1 mm metric
thread chaser (or tap) for the derailleur hanger (about $5 at www.biketoolssetc.com). I have bent
the derailleur hanger on a number of bikes, so I keep a derailleur hanger tool and a thread chaser
in my shop. Your LBS will have the chaser.

Yup, he fixed it for me. I will of course inform the prospective buyer that the thread might be a
bit munged so too much removing and refitting of the derailleur is not advisable. But at 2300 DKK or
300 euro for whats basically a new frame with new albeit cheap components you can't get everything.

Cheers Mikael

Quoted post said:

Originally posted by Mikael Seierup
Due to paint I munged the first few mm of the thread for the rear derailleur. Threaded hole on the
frame I mean. Any way to correct it?

/Mikael

I don't know if it is common practice in the bicycle industry to use Heli-coils to replace ruined threads, but if they are good enough to hold a heavy duty truck transmission in place, I think they might be worth a try.
Your local machine shop would be the place to find out.

Dan Burkhart said:

I don't know if it is common practice in the bicycle industry to use Heli-coils to replace ruined
threads, but if they are good enough to hold a heavy duty truck transmission in place, I think
they might be worth a try. Your local machine shop would be the place to find out.

When a rogue plastic bag demolished the rear derailleur and hanger on thread on Mrs Larrington's
Kingcycle, this was the fix that Bikefix applied, so I imagine that a helicoil with that particular
threading is fairly easy to get hold of.

--

Dave Larrington - legslarry.beerdrinkers.co.uklegslarry.beerdrinkers.co.ukOpen ↗
===========================================================
Editor - British Human Power Club Newsletter
bhpc.org.ukbhpc.org.ukOpen ↗
===========================================================

My auto and bike mechanic friends used to call it a
"helicoil."

--
--Scott
"Cletus Lee" <[email hidden]> wrote in message
"]news:[email hidden]...

Quoted message said:

In article <[email hidden]>,

[email hidden] says...

Quoted message said:

Quoted message said:

Due to paint I munged the first few mm of the thread for the rear

derailleur.

Quoted message said:

Quoted message said:

Threaded hole on the frame I mean. Any way to correct it?

If you can't re-tap the threads using Bryan's suggestion, There are

inserts that can be fitted into

Quoted message said:

the old hole. I think the process is to drill out the derailleur hole.

press in a derailleur sized

Quoted message said:

insert.

--

Cletus D. Lee
Bacchetta Giro
Lightning Voyager
clee.orgclee.orgOpen ↗
- Bellaire, TX USA -