Re: Broken clutch knob

Peter Santangeli

I haven't checked yet, but my gut is that the piece that is still in
there is not extraordinarily tight. I don't think it broke due to
tightening (I don't keep them that tight). I think what happened is
the big knob part got hit at some point, and the shaft broke. I seem
to remember that at one point this summer I noticed the knob wasn't
square to the mount. Not looking into how it was put together, I
thought to myself "hmmmm. Interesting construction that could let that
wobble like that but still tighten".

I realize now that what had probably had probably happened is the
aluminum had split but not broken right off. If I had realized the
(somewhat odd) construction of the "bolt" I would have backed it out
and replaced it right away. Live and learn.

Thanks for all the advice. I'll let you know how it goes. I've already
had both the Dec section and RA section back to AP at least once, so
I'd rather avoid another repair visit. I sold my backup G11 last week,
so it would leave me without a good mount!


--- In ap-gto@..., "Mark Galiyano Jr" <mgjr@...> wrote:

You *cannot* use the broken off piece or any other threaded
extractor. Whatever is glued to the stud must not be threaded. If
you do, there is no way to unsure tha the threads don't jam like a jam
nut arrangement. If an attempt is made to use glue, I would use a
crayon to wax up the whole inside, then a dremel or small drill bit to
clean up a spot for the bond, or even drill the size of a heavy duty
paper clip and glue that inside the hole.
All that said, I still think an easy out is the way to go. Maybe if
the rest of the clutches are loose, movement of the axis may help
loosen this one.

----- Original Message -----
From: steve_dashiell
To: ap-gto@...
Sent: Saturday, December 15, 2007 10:56 PM
Subject: [ap-gto] Re: Broken clutch knob

Since the top of the broken stud is 3 mm down in the threaded hole, if
glue of any sort is put on top of it and the other piece is threaded
in, any excess glue will be forced out of the space between the two
broken pieces and into the threads both above and below the break,
since there will be no where else the excess can go. I seriously
doubt that there is anything that can be done to seal the threads
adequately to prevent this, since the glue is relatively
incompressible. If the amount of glue used is so small that there is
no excess to squeeze out, it might work, but the proper amount is
probably difficult to estimate.


--- In ap-gto@..., "Mark Galiyano Jr" <mgjr@> wrote:
> You can protect the threads from the glue by putting wax at the
interface of the bolt and threads. Most glues will not adhear to wax
and it forms a fairly good barrier. The thing that troubles me is that
enough force was present to shear the bolt. I am not sure this can be
done without an easy out. I do think and easy out will work though.
Most of us that have had trouble with them were trying to get out
wrench-tightened bolt remains, not hand tightened.
> Best of luck,
> Mark
> ----- Original Message -----
> From: steve_dashiell
> To: ap-gto@...
> Sent: Saturday, December 15, 2007 8:17 PM
> Subject: [ap-gto] Re: Broken clutch knob
> The risk with this approach is that if any of the glue gets into the
> threads of the broken off stub, it could end up acting like a thread
> locker, making the broken piece difficult to remove at all, even
> proper equipment.
> Steve
> --- In ap-gto@..., "Bryon Schwartz" <bryonnmissy@>
> >
> >
> > If the screw part that is still in the mount is not stripped or
> > jammed into the thread wall maybe try crazy glueing, or some
> > strong epoxy, the knob back onto the bolt and let it set for
maybe a
> > day and then try twisting it out SLOWLY. This might work ONLY if
> > remaining part of the bolt is not jammed or stripped into the
> > walls.
> >
> > Just my $.02 and can't hurt to try. The only thing that could
> > is the bolt will shear again at the point where you glued it.
> >
> > Bryon
> >
> > --- In ap-gto@..., "Peter Santangeli" <peter@> wrote:
> > >
> > >
> > > Indeed the problem is bad... that part I'm holding is supposed
to be
> > > at least 3/4 of an inch long. The rest is in the mount.
> > >
> > > Pete
> > >
> >
> [Non-text portions of this message have been removed]

[Non-text portions of this message have been removed]

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