Gluing on Fabric

Hi All,

There are many homebuilts where the designer intends that the fabric be
attached to the wings solely by gluing. Aircraft such as the Corby Starlet,
Jodel D-18, Kitfox etc. These aircraft all use wider rib cap strips than is
normal to provide a large area for the glue to adhere to.

This practise is supported by calculations which show that the loading on
the glue joints is low (even in the presence of peel loads) and test data
that I have reviewed for the various glues in use.

However on the Polyfiber web site they claim that rib stitching MUST be
used - no exceptions even if the designer states otherwise.

What is the experience from the field ? I am interested in the experiences
of RAH members. If you have glued fabric on without rib stitching was it a
success of failure ? What was the airplane, how wide are the cap strips and
what glue and fabric were used. If failures occurred what was the nature of
these ???

Thanks,

Steve

"......... :-))" wrote in message
u...
What is the experience from the field ? I am interested in the
experiences
of RAH members. If you have glued fabric on without rib stitching was it a
success of failure ? What was the airplane, how wide are the cap strips
and
what glue and fabric were used.

I believe the Emeraude built by Ted Hendrickson circa 1977 relied on glue.
His cap strips were about 3/4" wide. The plane is still flying well almost
thirty years later and looks like new. I've been told it has exceeded 200
mph during aerobatics many times. Nonetheless, I stitched mine.

Rich "Belt & suspenders" S.

On Sun, 14 Aug 2005 22:05:40 +1000, "......... :-\)\)"
wrote:


What is the experience from the field ? I am interested in the experiences
of RAH members. If you have glued fabric on without rib stitching was it a
success of failure ? What was the airplane, how wide are the cap strips and
what glue and fabric were used. If failures occurred what was the nature of
these ???

Thanks,

Steve

The fabric on my 20 year old Jungster II is glued on. On the wings
there are only 3 fabric bays the rest is covered with plywood and
fabric. The cap strips are one inch wide. I tested some strips using
several adhesives including polytak and the only one that gave
satisfactory results was Goodyear Pliobond. The Ailerons, Rudder and
Elevators are all glued on. The fabric was uncertified Dacron which is
available from several sources. As I recall the Pliobond was applied
heavily to unvarnished cap strips, the fabric was attached at leading
and trailing edges and shrunk then the cap strips were moistened with
a solvent, I can't remember if it was acetone or MEK to bring the
Pliobond up through the fabric. It was then coated with Nitrate and
Butyrate dopes and finished.

Ed Sullivan

You might want to consider the results of the separation that occurred with
Steve Witman's Stits fabric glued onto the plywood wing that failed over
Alabama. How do you regularly inspect the glue for separation on a regular
basis?
"......... :-))" wrote in message
u...
Hi All,

There are many homebuilts where the designer intends that the fabric be
attached to the wings solely by gluing. Aircraft such as the Corby
Starlet,
Jodel D-18, Kitfox etc. These aircraft all use wider rib cap strips than
is
normal to provide a large area for the glue to adhere to.

This practise is supported by calculations which show that the loading on
the glue joints is low (even in the presence of peel loads) and test data
that I have reviewed for the various glues in use.

However on the Polyfiber web site they claim that rib stitching MUST be
used - no exceptions even if the designer states otherwise.

What is the experience from the field ? I am interested in the
experiences
of RAH members. If you have glued fabric on without rib stitching was it a
success of failure ? What was the airplane, how wide are the cap strips
and
what glue and fabric were used. If failures occurred what was the nature
of
these ???

Thanks,

Steve

On Sun, 14 Aug 2005 23:49:09 -0500, "Robert Little"
wrote:

You might want to consider the results of the separation that occurred with
Steve Witman's Stits fabric glued onto the plywood wing that failed over
Alabama. How do you regularly inspect the glue for separation on a regular
basis?

Steve Witman's incident was one case out of hundreds of aircraft with
fabric bonded over plywood. You can't condemn them all from one case.
I just run it up to 160 mph and pull a few G's now and then , so far
so good. I'm 76 years old and don't plan on living forever!

Ed Sullivan

I'm curious, do you spread glue onto all the plywood, or do you glue
specific area's so the fabric can shrink?
Lou

Actually, the fabric on Steve's O-O Special wasn't "glued" at all -
that was the problem.
It was simply "doped" on - just like he had done for a hundred years or
so.

But the fabric was dacron this time.....
Not cotton.

Richard

On 15 Aug 2005 01:22:16 -0700, "Lou" wrote:

I'm curious, do you spread glue onto all the plywood, or do you glue
specific area's so the fabric can shrink?
Lou

You know it has been nearly twenty years since I did it, so without
looking up some paper work I don't exactly remember, however on the
open bays with cap strip I attached the leading and trailing edges,
and then shrunk the fabric before applying the solvent to attach the
fabric to the cap strips. I think I did the same on the areas of solid
plywood. On them I used a mixture of nitrate dope and a fabric
adhesive. It may have been Sureseam. It was installed heavily over
unvarnished ply and then brought up through the weave with a solvent.

Ed

"Richard Lamb" wrote in message
oups.com...
Actually, the fabric on Steve's O-O Special wasn't "glued" at all -
that was the problem.
It was simply "doped" on - just like he had done for a hundred years or
so.

But the fabric was dacron this time.....
Not cotton.

Richard
PLEASE don't confuse us with facts!
g
--
Jim in NC

(very contrite) Sorry?!?