Rib stitching vs glueing

Anthony W wrote:
wrote:

What about the 3rd option from the Tony Bengals books, covering the wing
with thin fiber glass cloth and resin?


Just in case anyone wants to find his books its _Tony Bingelis.

Fiberglass wings are not fabric wings. You might as well say,
hey, why not cover them with aluminum sheet metal.

Also, I _think_ fiberglass wings will be heavier.

I may have spelled his name wrong but from your answer, I don't think
you've read his books or at least this part.


I have four of his books, and have read parts of each. Which
one are your thinking of?

Meaning no disrespect to Mr Bingelis, it remains the case that
fiberglass wings are not fabric wings.

--

FF

wrote:
Anthony W wrote:

wrote:


What about the 3rd option from the Tony Bengals books, covering the wing
with thin fiber glass cloth and resin?


Just in case anyone wants to find his books its _Tony Bingelis.

Fiberglass wings are not fabric wings. You might as well say,
hey, why not cover them with aluminum sheet metal.

Also, I _think_ fiberglass wings will be heavier.

I may have spelled his name wrong but from your answer, I don't think
you've read his books or at least this part.



I have four of his books, and have read parts of each. Which
one are your thinking of?

Meaning no disrespect to Mr Bingelis, it remains the case that
fiberglass wings are not fabric wings.

I'd have to find it but I think it's in the yellow book. I only have 2
of the 4 in the series. I won a gift certificate to Amazon.com and they
didn't have anything else I wanted at the time for the $50 I had to spend.

Anyway Mr. Bingelis discuses covering wood wings and offers covering
them with thin glass cloth and resin as an option to regular fabric. As
I recall he says that if done right the weight is only slightly more and
it makes for stronger wings.

I've never built a plane, I was just asking if some one here had tried
this method recommended by known expert on the subject.

Tony

On Thu, 13 Oct 2005 09:13:37 -0700, Smitty Two
wrote:

In article ,
Stealth Pilot wrote:


btw dont be beguiled by the semantics.
the glue strength doesnt change with the glue area since it is a force
per unit area measurement.
the glue area directly changes the amount of total force that the rib
fabric join can stand.
a pound per square inch strength applied to a square inch can hold a
pound
a pound per square inch strength applied over a square foot can hold
one hundred and fourty four pounds.

Stealth Pilot
Australia

I'll bite into this topic from an intellectual curiosity perspective.
What are the forces acting on a rag plane that would tug against the rib
bond? Source? Direction? Magnitude? How common are such bond failures?
What is the cause? Poor surface prep or other application shortcomings?
Deterioration of the glue or fabric over time? Other?

I'll reply for the other guys benefit. I dont know what you'll read
into this :-)

glue bonds fail over time from the stress rise at the edge of the
joint.

air pressure will create a force perpendicular to the surface.
have a look in a text at one of the manometer photos of a wing section
under test to get an idea of the pressure distribution.

the predominant cause of failure in fabric bonds is the reversing
loads created by turbulence from the slipstream off the prop. outside
of the slipstream competently bonded fabric seldom fails.
the fabric bond fails from the edge and slowly the failure creeps
inward across the joint. ribstitching in the area of the slipstream
works to correct the problem because it doesnt have stress risers
occurring at the edges of the thread.

my method of checking the stits fabric on my tailwind is to look
inside the tailcone out in the bright sunlight and pick the areas
where the uv opaquing was poorly done. I then make the "bird" with one
hand and walk along those areas banging the finger into the fabric as
hard as my hand will allow. If I ever get a puncture I'll initially
repair it. If I get areas of punctures then it is in for a refabric.
I've wanted to refabric the aircraft for a few years now but the stits
seems to have an infinite life. I cant detect any deterioration other
than in the visual appearance of the paint.

not a complete disertation but then the other guy wasnt asking much.
Stealth Pilot

On 13 Oct 2005 20:26:10 -0700, wrote:


Anthony W wrote:
wrote:

What about the 3rd option from the Tony Bengals books, covering the wing
with thin fiber glass cloth and resin?


Just in case anyone wants to find his books its _Tony Bingelis.

Fiberglass wings are not fabric wings. You might as well say,
hey, why not cover them with aluminum sheet metal.

Also, I _think_ fiberglass wings will be heavier.

I may have spelled his name wrong but from your answer, I don't think
you've read his books or at least this part.


I have four of his books, and have read parts of each. Which
one are your thinking of?

Meaning no disrespect to Mr Bingelis, it remains the case that
fiberglass wings are not fabric wings.

are you sure?
razorback is a fabric system that uses fibreglass.
Stealth Pilot

Stealth Pilot wrote:
On 13 Oct 2005 20:26:10 -0700, wrote:


Anthony W wrote:
wrote:

What about the 3rd option from the Tony Bengals books, covering the wing
with thin fiber glass cloth and resin?


Just in case anyone wants to find his books its _Tony Bingelis.

Fiberglass wings are not fabric wings. You might as well say,
hey, why not cover them with aluminum sheet metal.

Also, I _think_ fiberglass wings will be heavier.

I may have spelled his name wrong but from your answer, I don't think
you've read his books or at least this part.


I have four of his books, and have read parts of each. Which
one are your thinking of?

Meaning no disrespect to Mr Bingelis, it remains the case that
fiberglass wings are not fabric wings.

are you sure?
razorback is a fabric system that uses fibreglass.
Stealth Pilot

Thanks. With a little googling I learned that Razorback is
fiberglass cloth filled with butyrate dope. I daresay that
is significanlty differant from fiberglass cloth filled with
epoxy or polyester resin.

Whether or not that makes a razorback wing a fiberglass wing
or a fabric wing would seem to be a matter of interpretation.
I guess I'd call it a hybrid.

Like Anthony W, I have not built a plane.

Last night I went through Bingelis' books and found that the
fiberglass section of the yellow book (Sportplane Construction
Techniques is the title IIRC) dealt with gas tanks, wheel pants,
cowls and such. He didn't really address wing covering in that
book.

In his blue book (Sportplane Builder) he has a Chapter near the
end on Dacron, but Chapter 5 is 'Fiberglass Tips' and has a section
'Fiberglass Your Bird'. This discusses using lightweight
fiberglass cloth and resin to cover a plywood fuselage, similar
to light boat construction. (BTW, there is a boatbuilding
technique called 'stich and glue' which looks to be adaptable
to stressed skin construction.) He says he first used the material
to cover the tailfeathers of an Emeraude, are those skinned with
plywood? Looking at photos on the net it appears that some rudders
are, and some aren't.

I would not rely on the book covers being the same color with
each printing, nor on my searching late last night being thorough.

But I don't think he suggests fiberglass cloth and resin over
ribs with nothing else underneath. ISTM that the cloth would
sag between the ribs and unlike the dope in the razorback system,
the curing resin would not draw it tight, unless you found
a resin that would shrink. Hmm, doesn't some poylester resin
shrink when it cures?

--

FF

On 12 Oct 2005 14:33:47 -0700, wrote:



Thoughts? Thanks

Neal

On my 20 year old Jungster II I attached the fabric to 1" wide
capstrips. They were not varnished, they were generously coated with
Goodyear Pliobond. The wing was then covered and the ribs were brushed
over with acetone or MEK, I forget which to pull the adhesive up
through the fabric. So far so good and up to 170 mph in a dive.

The technique Tony Bingelis was refering to in his book was covering a
plywood covered aircraft in model airplane weight fiberglas. I used
the same material for the last layer on my wing and empennage tips as
well as the leading edge. Makes a real smooth finish without excess
filling.

Ed Sullivan

wrote:
On 12 Oct 2005 14:33:47 -0700, wrote:

I was reading some information on Fisher Celebrity builders websites
and saw that one builder did not like the idea of glueing the fabric to
the ribs as per the plans. The ribs on the Celebrity are very thin and
he didn't think there was enough glue area for a satisfactory bond, so
he rib stitched.

The Celebrity is a biplane with a top speed of 95 mph, right? Has it
been a problem? Have any of the Celebrity's that had the fabric glued
had the fabric come unstuck? Ever?


I vaguely remember reading in the FAA/NTSB archive about such an
incident. It was a while ago, so I may be a bit off. What I remember
was that the pilot was killed on impact and apparently he was aware of
some minor seperation and continued to fly the aircraft until it failed
catastrophically. Might have been another bird, but I think it was a
celebrity. I'm not 100% sure though. You might try searching the
accident database for the celebrity if you haven't already.

-Matt


If not, why should it be considered an issue?

On the other hand, if the guy just cannot live with attaching the
fabric with glue, even if nothing bad has ever happened, he can
certainly rib stitch. It won't hurt anything but his wallet, a bit,
and add to the length of time building.

Corky Scott

wrote:
wrote:
On 12 Oct 2005 14:33:47 -0700, wrote:

I was reading some information on Fisher Celebrity builders websites
and saw that one builder did not like the idea of glueing the fabric to
the ribs as per the plans. The ribs on the Celebrity are very thin and
he didn't think there was enough glue area for a satisfactory bond, so
he rib stitched.

The Celebrity is a biplane with a top speed of 95 mph, right? Has it
been a problem? Have any of the Celebrity's that had the fabric glued
had the fabric come unstuck? Ever?


I vaguely remember reading in the FAA/NTSB archive about such an
incident. It was a while ago, so I may be a bit off. What I remember
was that the pilot was killed on impact and apparently he was aware of
some minor seperation and continued to fly the aircraft until it failed
catastrophically. Might have been another bird, but I think it was a
celebrity. I'm not 100% sure though. You might try searching the
accident database for the celebrity if you haven't already.


That sounds pretty much like what happened to Steve Wittman.
He put off fixing the problem until after he got to Oshkosh.

--

FF

wrote:
wrote:
On 12 Oct 2005 14:33:47 -0700, wrote:

I was reading some information on Fisher Celebrity builders websites
and saw that one builder did not like the idea of glueing the fabric to
the ribs as per the plans. The ribs on the Celebrity are very thin and
he didn't think there was enough glue area for a satisfactory bond, so
he rib stitched.

The Celebrity is a biplane with a top speed of 95 mph, right? Has it
been a problem? Have any of the Celebrity's that had the fabric glued
had the fabric come unstuck? Ever?


I vaguely remember reading in the FAA/NTSB archive about such an
incident. It was a while ago, so I may be a bit off. What I remember
was that the pilot was killed on impact and apparently he was aware of
some minor seperation and continued to fly the aircraft until it failed
catastrophically. Might have been another bird, but I think it was a
celebrity. I'm not 100% sure though. You might try searching the
accident database for the celebrity if you haven't already.


That sounds pretty much like what happened to Steve Wittman.
He put off fixing the problem until after he got to Oshkosh.

--

FF

wrote

I vaguely remember reading in the FAA/NTSB archive about such an
incident. It was a while ago, so I may be a bit off. What I remember
was that the pilot was killed on impact and apparently he was aware of
some minor seperation and continued to fly the aircraft until it failed
catastrophically. Might have been another bird, but I think it was a
celebrity. I'm not 100% sure though. You might try searching the
accident database for the celebrity if you haven't already.

I am not an authority on the facts, so I didn't bring up the name of the
incident that I was thinking of, but since nobody else with all of the facts
has, I will.

Steve Whitman(sp?), namesake of the OSH airport, racer, and designer of the
Tailwind (among others) was killed in such an unbonding incident. I don't
recall the details, but I recall that he did something wrong, or against
other's recommendations.

The planes he designed were much higher performance crafts than what the OP
was asking about. I'm sure he can google the details.
--
Jim in NC