ASK21 air brake bell crank repair

[Geoff Brown]

I've been trying to find anything on the www that shows how to access the
pivot bolt that secures the air brake bell crank that is located in the air
brake box on an ASK21.

I've had no luck. Does anyone else have any pointers?

Thanks

[Bob Kuykendall]

On Dec 23, 6:31*am, Geoff Brown
> wrote:

> Does anyone else have any pointers?

I have a sawzall...

[[email protected]]

On Dec 23, 9:31*am, Geoff Brown
> wrote:
> I've been trying to find anything on the www that shows how to access the
> pivot bolt that secures the air brake bell crank that is located in the air
> brake box on an ASK21.
>
> I've had no luck. *Does anyone else have any pointers?
>
> Thanks

Access hole on bottom required. Most likely aft of spar.
You would best be served by contacting the factory on this one. Bad
stuff happens when you cut the spar cap.
UH

[Papa3]

On Dec 23, 11:03*am, wrote:
> On Dec 23, 9:31*am, Geoff Brown
>
> > wrote:
> > I've been trying to find anything on the www that shows how to access the
> > pivot bolt that secures the air brake bell crank that is located in the air
> > brake box on an ASK21.
>
> > I've had no luck. *Does anyone else have any pointers?
>
> > Thanks
>
> Access hole on bottom required. Most likely aft of spar.
> You would best be served by contacting the factory on this one. Bad
> stuff happens when you cut the spar cap.
> UH

"I'm a little hazy on this whole good/bad thing..."

P3

[bildan]

On Dec 23, 7:31*am, Geoff Brown
> wrote:
> I've been trying to find anything on the www that shows how to access the
> pivot bolt that secures the air brake bell crank that is located in the air
> brake box on an ASK21.
>
> I've had no luck. *Does anyone else have any pointers?
>
> Thanks

I've been associated with a couple of these situations. If your shop
knows exactly where, one or two 5cm round holes can be cut in the
bottom skin through which a wrench will fit. A perfectly round hole
is a simple repair and you'll never see where it was.

Why do you need access?

[Geoff Brown]

At 16:26 23 December 2010, bildan wrote:
>On Dec 23, 7:31=A0am, Geoff Brown
> wrote:
>> I've been trying to find anything on the www that shows how to access
>the
>> pivot bolt that secures the air brake bell crank that is located in
the
>a=
>ir
>> brake box on an ASK21.
>>
>> I've had no luck. =A0Does anyone else have any pointers?
>>
>> Thanks
>
>I've been associated with a couple of these situations. If your shop
>knows exactly where, one or two 5cm round holes can be cut in the
>bottom skin through which a wrench will fit. A perfectly round hole
>is a simple repair and you'll never see where it was.
>
>Why do you need access?
>

The ball race that couples to the air brake paddle side has corroded and
needs replacing. My shop also reckons a couple of holes will be needed to
allow access by wrenches (though the hope is that bolt doesn't have to be
fully retracted). We were hoping that we could find some pictures of what
we might find before cutting any holes.

[bildan]

On Dec 24, 2:15*pm, Geoff Brown
> wrote:
> At 16:26 23 December 2010, bildan wrote:
>
>
>
> >On Dec 23, 7:31=A0am, Geoff Brown
> > wrote:
> >> I've been trying to find anything on the www that shows how to access
> >the
> >> pivot bolt that secures the air brake bell crank that is located in
> the
> >a=
> >ir
> >> brake box on an ASK21.
>
> >> I've had no luck. =A0Does anyone else have any pointers?
>
> >> Thanks
>
> >I've been associated with a couple of these situations. *If your shop
> >knows exactly where, one or two 5cm round holes can be cut in the
> >bottom skin through which a wrench will fit. *A perfectly round hole
> >is a simple repair and you'll never see where it was.
>
> >Why do you need access?
>
> The ball race that couples to the air brake paddle side has corroded and
> needs replacing. *My shop also reckons a couple of holes will be needed to
> allow access by wrenches (though the hope is that bolt doesn't have to be
> fully retracted). *We were hoping that we could find some pictures of what
> we might find before cutting any holes.

Yep, I've seen that. The ASK-21 spoiler boxes, like most composite
gliders, don't have drain holes for water, which has leaked in around
the spoiler cap, to escape. If a glider is to be tied out, it's a
good idea to tape some colorful plastic sheet over the spoilers to
keep water out. I worry a little about using white wing gap tape to
seal the spoiler boxes - someone might not see it and take off with
the spoilers taped shut.

[Bob Kuykendall]

On Dec 24, 1:15*pm, Geoff Brown
> wrote:

> The ball race that couples to the air brake paddle side has corroded and
> needs replacing...

I'm interested in understanding your terminology. What is the thing
you call a "ball race?"

Thanks, Bob K.

[Geoff Brown]

At 02:54 25 December 2010, Bob Kuykendall wrote:
>On Dec 24, 1:15=A0pm, Geoff Brown
> wrote:
>
>> The ball race that couples to the air brake paddle side has corroded
and
>> needs replacing...
>
>I'm interested in understanding your terminology. What is the thing
>you call a "ball race?"
>
>Thanks, Bob K.
>

See http://en.wikipedia.org/w/index.php?title=Ball_race&redirect=no

Geoff

[JJ Sinclair]

On Dec 23, 6:31*am, Geoff Brown
> wrote:
> I've been trying to find anything on the www that shows how to access the
> pivot bolt that secures the air brake bell crank that is located in the air
> brake box on an ASK21.
>
> I've had no luck. *Does anyone else have any pointers?
>
> Thanks

Geoff,
If I understand the problem, you need to drill a hole on the forward
side of the spar in order to get at the other end of the bolt that
secures the air brake pivot bolt. I would tap-test the width of the
spar cap and then add an inch to show where to drill an exploritory
hole. Start with 1/16 drill and stop if you get anything other than
skin/foam/skin. If that goes OK, then widen it out to 1/2" in order to
get a small light and mirror in there. Now you can adjust the hole as
necessary to remove/replace the bolt/nut. I have replaced the inner
skin with pre-cured glass piece that overlaps the inner skin at 40:1
(about 3/4"), held in place with 3 strings that pull it up until epoxy
cures.Then replaced the foam core (plug with no scarf) followed with a
normal 40:1 scarf on the outer skin replacement + one layer of 92110
extending out another 1/2" to make sure none of the uni tries to get
loose.
Hope this helps,
JJ

[bildan]

On Dec 25, 7:07*am, JJ Sinclair > wrote:
> On Dec 23, 6:31*am, Geoff Brown
>
> > wrote:
> > I've been trying to find anything on the www that shows how to access the
> > pivot bolt that secures the air brake bell crank that is located in the air
> > brake box on an ASK21.
>
> > I've had no luck. *Does anyone else have any pointers?
>
> > Thanks
>
> Geoff,
> If I understand the problem, you need to drill a hole on the forward
> side of the spar in order to get at the other end of the bolt that
> secures the air brake pivot bolt. I would tap-test the width of the
> spar cap and then add an inch to show where to drill an exploritory
> hole. Start with 1/16 drill and stop if you get anything other than
> skin/foam/skin. If that goes OK, then widen it out to 1/2" in order to
> get a small light and mirror in there. Now you can adjust the hole as
> necessary to remove/replace the bolt/nut. I have replaced the inner
> skin with pre-cured glass piece that overlaps the inner skin at 40:1
> (about 3/4"), held in place with 3 strings that pull it up until epoxy
> cures.Then replaced the foam core (plug with no scarf) followed with a
> normal 40:1 scarf on the outer skin replacement + one layer of 92110
> extending out another 1/2" to make sure none of the uni tries to get
> loose.
> Hope this helps,
> JJ

Strike's me this thread could be merged with the one on cheap video
cameras. A search of Ebay for "USB endoscope" turns up some cheap
options. One could be used for inspecting the interior of gliders
through tiny holes. IIRC, something like this was used to inspect the
interior of DUO wings after an AD.

[Geoff Brown]

Thanks for all your help - I'll let you know how we got on.

On Dec 23, 6:31=A0am, Geoff Brown wrote:
I've been trying to find anything on the www that shows how to access
.....