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Brian Huffaker
May 25th 04, 12:14 AM
It's annual time on the starduster, and several of the screw holds
to hold on the inspection plates have been enlarged over the years to
the point where a screw won't stay in the whole. Around each inspection
hole, there is a thickened area in the fabric that has been drilled
or punched to recieve the screws. We are using sheet metal screws.
I don't know what covering system was used, but could probably find
out (it was recovered several years before I bought into the
partnetship). Is there some kind of filler that could be placed in
these holes and then drilled out back to a smaller size so that the
screws would stay in?

Thanks in advance for any ideas.

Brian Huffaker, DSWL )
RV-8A 80091 Riviting foward lower fuseage skin
1/4 Starduster Too N23UT flying.

Ernest Christley
May 25th 04, 03:27 AM
Brian Huffaker wrote:
> It's annual time on the starduster, and several of the screw holds
> to hold on the inspection plates have been enlarged over the years to
> the point where a screw won't stay in the whole. Around each inspection
> hole, there is a thickened area in the fabric that has been drilled
> or punched to recieve the screws. We are using sheet metal screws.
> I don't know what covering system was used, but could probably find
> out (it was recovered several years before I bought into the
> partnetship). Is there some kind of filler that could be placed in
> these holes and then drilled out back to a smaller size so that the
> screws would stay in?
>
> Thanks in advance for any ideas.
>
> Brian Huffaker, DSWL )
> RV-8A 80091 Riviting foward lower fuseage skin
> 1/4 Starduster Too N23UT flying.

A toothpick dipped in your favorite glue. Several toothpicks if the
hole is large.

--
http://www.ernest.isa-geek.org/
"Ignorance is mankinds normal state,
alleviated by information and experience."
Veeduber

Morgans
May 25th 04, 03:32 AM
"Brian Huffaker" > wrote in message
...
>
> It's annual time on the starduster, and several of the screw holds
> to hold on the inspection plates have been enlarged over the years to
> the point where a screw won't stay in the whole. Around each inspection
> hole, there is a thickened area in the fabric that has been drilled
> or punched to recieve the screws. We are using sheet metal screws.
> I don't know what covering system was used, but could probably find
> out (it was recovered several years before I bought into the
> partnetship). Is there some kind of filler that could be placed in
> these holes and then drilled out back to a smaller size so that the
> screws would stay in?
>
> Thanks in advance for any ideas.
>
> Brian Huffaker,

I am no help for the fabric repair, but repairing the wood is right up my
alley. Drill the wood just enough to clean out the hole and make it a size
slightly larger than a hardwood dowel. Use the smallest possible. Inject
some epoxy into the hole, and onto the dowel, then tap it into the hole.
Re-drill the correct size hole for the screw, and that part is done.

If you ever recover, make sure the area that the inspection hole is in can
take it, and use a blind wood nut and machine screw. IMHO, that is what
should have been used in the first place. It might be possible to use one
right now, depending on the location, and material the screw was in, and
what the structural loads are in that area.
--
Jim in NC


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Jim Weir
May 25th 04, 03:40 AM
Tinnermans?

Jim



->Brian Huffaker wrote:
->> It's annual time on the starduster, and several of the screw holds
->> to hold on the inspection plates have been enlarged over the years to
->> the point where a screw won't stay in the whole. Around each inspection
->> hole, there is a thickened area in the fabric that has been drilled
->> or punched to recieve the screws. We are using sheet metal screws.
->> I don't know what covering system was used, but could probably find
->> out (it was recovered several years before I bought into the
->> partnetship). Is there some kind of filler that could be placed in
->> these holes and then drilled out back to a smaller size so that the
->> screws would stay in?



Jim Weir (A&P/IA, CFI, & other good alphabet soup)
VP Eng RST Pres. Cyberchapter EAA Tech. Counselor
http://www.rst-engr.com

coustanis
May 25th 04, 02:46 PM
Brian Huffaker wrote:
>
> It's annual time on the starduster, and several of the screw holds
> to hold on the inspection plates have been enlarged over the years to
> the point where a screw won't stay in the whole. Around each inspection
> hole, there is a thickened area in the fabric that has been drilled
> or punched to recieve the screws. We are using sheet metal screws.
> I don't know what covering system was used, but could probably find
> out (it was recovered several years before I bought into the
> partnetship). Is there some kind of filler that could be placed in
> these holes and then drilled out back to a smaller size so that the
> screws would stay in?
>
> Thanks in advance for any ideas.
>
> Brian Huffaker, DSWL )
> RV-8A 80091 Riviting foward lower fuseage skin
> 1/4 Starduster Too N23UT flying.

Fill the hole with epoxy and redrill.
Works a champ.

Morgans
May 25th 04, 08:41 PM
"Todd Pattist" > wrote >
> Using a dowel aligns the grain with the axis of the screw,
> whereas the wood probably had the grain running
> perpendicular originally. Is this a problem with a dowel?
> I know end grain screws don't usually hold all that well.
> The plug could be cut with a plug cutter to get
> perpendicular grain, but then I'd worry about splitting.
> Comments?
> Todd Pattist
> (Remove DONTSPAMME from address to email reply.)
> ___
> Make a commitment to learn something from every flight.
> Share what you learn.

The fact that the dowel is not cross grain, is more than made up for, by the
fact that it is hardwood, and not spruce.
--
Jim in NC




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bubba
May 26th 04, 04:33 AM
Why not ignore the original holes and add new holes!
Should be good and tight.

Dave

Morgans wrote:
> "Todd Pattist" > wrote >
>
>>Using a dowel aligns the grain with the axis of the screw,
>>whereas the wood probably had the grain running
>>perpendicular originally. Is this a problem with a dowel?
>>I know end grain screws don't usually hold all that well.
>>The plug could be cut with a plug cutter to get
>>perpendicular grain, but then I'd worry about splitting.
>>Comments?
>>Todd Pattist
>>(Remove DONTSPAMME from address to email reply.)
>>___
>>Make a commitment to learn something from every flight.
>>Share what you learn.
>
>
> The fact that the dowel is not cross grain, is more than made up for, by the
> fact that it is hardwood, and not spruce.

Ron Wanttaja
May 26th 04, 05:08 AM
On Wed, 26 May 2004 03:33:43 GMT, bubba > wrote:

>Why not ignore the original holes and add new holes!
>Should be good and tight.

My thought, too, *if* the inspection panels were round and didn't have any
trim stripes painted on them. Won't work, otherwise.

Ron Wanttaja

jls
May 26th 04, 02:32 PM
"Brian Huffaker" > wrote in message
...
>
> It's annual time on the starduster, and several of the screw holds
> to hold on the inspection plates have been enlarged over the years to
> the point where a screw won't stay in the whole. Around each inspection
> hole, there is a thickened area in the fabric that has been drilled
> or punched to recieve the screws. We are using sheet metal screws.
> I don't know what covering system was used, but could probably find
> out (it was recovered several years before I bought into the
> partnetship). Is there some kind of filler that could be placed in
> these holes and then drilled out back to a smaller size so that the
> screws would stay in?
>
> Thanks in advance for any ideas.
>
> Brian Huffaker, DSWL )
> RV-8A 80091 Riviting foward lower fuseage skin
> 1/4 Starduster Too N23UT flying.

The round inspection hole reinforcements I have seen are made of plastic and
they do get old and brittle and screw holes get elongated. They are
usually thin plastic rings that have been sandwiched between the wing's
fabric and a pinked-edge patch. Inspection covers best for these are round
aluminum plates which have attached clips 180 deg. apart which you push over
the reinforced hole and then line up the inspection plate so that it is
centered over the hole. The clips holding the cover to the fabric are
hidden inside the wing. On the faster fabric-covered airplanes like a
Pitts or Starduster the inspection cover has an inner concavity which
centers the cover and keeps it from slipping off or off-center. I have
seen some builders drill through the clips and use screws to make them hold
more tightly.

Where I have inspection plates attached to the fabric with screws, I bond a
narrow strip or plate of 016 or 020 aluminum inside the perimeter of the
hole and then use a fabric patch doubler and fold and glue it on securely
with Poly-Tak so that the aluminum reinforcement is encapsulated in fabric.
Then I drill through for the inspection cover screws and VOILA!, the
inspection cover hides the patching and the fabric doubler and lasts
forever.

Brian Huffaker
May 26th 04, 07:47 PM
Thanks for the ideas. Most won't work tho. These are rectangular
inspection holes with screws holding the cover plates on. The enlarged
holes are in the thickened fabric sections (there may be some plastic
embedded in there, but it doesn't look like it) The holes that go into
wood are fine. I was hoping that somebody would have experience with
a glue/epoxy something that could be used to fill in the old holes
without harming the fabric.

Sorry I can't take a picture, I'm on call this week and can't get up
to the airport.

Brian Huffaker )
RV-8A #80091 Riviting lower fuse subfloor
Starduster Too N23UT flying

Richard Lamb
May 27th 04, 02:47 AM
Brian Huffaker wrote:
>
> Thanks for the ideas. Most won't work tho. These are rectangular
> inspection holes with screws holding the cover plates on. The enlarged
> holes are in the thickened fabric sections (there may be some plastic
> embedded in there, but it doesn't look like it) The holes that go into
> wood are fine. I was hoping that somebody would have experience with
> a glue/epoxy something that could be used to fill in the old holes
> without harming the fabric.
>
> Sorry I can't take a picture, I'm on call this week and can't get up
> to the airport.
>
> Brian Huffaker )
> RV-8A #80091 Riviting lower fuse subfloor
> Starduster Too N23UT flying

Someone already suggested making backing plates from thin aluminum
sheet metal. Personally, that's the way I think I'd go about it.

Use clear shoe-goo to install the backing plates inside the fabric?
That should hold it in place when all the screws are removed.

It sounds like you are just screwing to the fabric in places...


Best of luck,

Richard Lamb

Brian Whatcott
May 29th 04, 02:07 AM
On Mon, 24 May 2004 23:14:10 +0000 (UTC), Brian Huffaker
> wrote:

>
> It's annual time on the starduster, and several of the screw holds
>to hold on the inspection plates have been enlarged over the years to
>the point where a screw won't stay in the whole. Around each inspection
>hole, there is a thickened area in the fabric that has been drilled
>or punched to recieve the screws. We are using sheet metal screws.
>I don't know what covering system was used, but could probably find
>out (it was recovered several years before I bought into the
>partnetship). Is there some kind of filler that could be placed in
>these holes and then drilled out back to a smaller size so that the
>screws would stay in?
>
> Thanks in advance for any ideas.
>
> Brian Huffaker, DSWL )
> RV-8A 80091 Riviting foward lower fuseage skin
> 1/4 Starduster Too N23UT flying.

Rivnuts (aluminum expanding shank), or
Rawlnuts (rubber expanding shank) are possibilities, I suppose?

Brian W

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