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Old March 19th 07, 10:58 PM posted to rec.aviation.homebuilt
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Default Flyin on the Cheap -- Sewing

It's a 'Cushion Needle,' okay? Yeah, you can call it a 'Rib Stitching
Needle' if you want to. But expect the price to double (or more).
Sometimes it's called a 'Quilting Needle,' 'Button Needle' or just the
generic 'Long Upholstery Needle' but whatever it's called, you need at
least one and more is generally better.

Usta cost about fifty cents for a 10-inch upholstery needle (about
1955). Over the years I accumulated quite a few of them, sharp end
stuck in a cork. My dad had about a dozen of them in a piece of
tubing in one of his tool boxes when he passed away and they fell to
me, my younger brother being strictly a rotary-wing sorta guy.
Although when he died a few years later I found an assortment of
needles in his kit, including a couple of long ones.

Some guys who write to me about Flying on the Cheap can't get real
steel needles. Sometimes it's because they simply aren't available
and sometimes it's because they're too expensive. Sounds silly but
it's true since a lotta guys who write to me do so from foreign
countries. They've got the same yen to fly as anybody else but Lord,
the troubles they run into. Ali went so far as to heat a bed spring,
straighten it out and forge an eye on one end. After doing so he
asked if a needle having a diameter of 1.5mm and a length of 23cm
would be suitable, to which I replied: "Oh my yes!" although forging a
dozen needles might leave you sleeping on the ground, which is why I
advised him to use bamboo.

The bamboo needles were about twelve inches long with a diameter of
3.7mm (about 0.145"). It took several messages to work-out their
fabrication and additional exchanges to discuss the size of the hole.
(Being a grass rather than a wood, bamboo has a perfectly linear
grain, meaning it splits evenly.) After doing one-half of the
elevator, which needed only a short needle but it was something he
could do without assistance, Ali saw that the size of the hole was of
no consequence since it was completely covered by the finishing tapes.

Patel's problem was similar in that he could not find 'suitable
string.' ('Thread' lead to some confusion, as did 'cord' but 'string'
served well enough.) But he did have access to 100% polyester
'string' having a strength of 'approximately 3 kilograms in five
trials' and wondered if he could spin several strands together, which
lead to another affirmative from me and an interesting exchange in the
principle of rope-making, since you can't simply spin the strands
together. Fortunately, Patel grasped the principle at once since he
also has a strong interest in Robotics (or at least, in small gear
trains) and owns a hand-powered drill of which he is justifiably
proud, along with a real carpenter's brace. The result was an
unlimited supply of rib-lacing cord having a breaking strain of about
20 kilograms, more than enough to satisfy the strictest of CAA
inspectors.

American homebuilders have it pretty easy, being able to buy suitable
needles and string :-) But if you'd care to see how others have done
it, a shish-kabob skewer makes a good rib stitching needle. Simply
sand the dull end to a thickness of about 1/16th of an inch and use a
small drill bit to connect a series of holes to form the eye. Sanding
and a bit of varnish will make it smooth enough for several wings-
worth of rib-stitches. Sharpen a nail or wire to make the initial
hole in the doped fabric; bamboo must be re-sharpened too frequently
to make it practical for punching its own holes. Don't worry about
the size of the hole, it will vanish when you apply the finishing
tapes.

And it doesn't absolutely HAVE to be a Seine Knot. A plain old-
fashioned Square Knot does just fine, assuming you're willing to tie-
off each stitch.

Just to add to the difficulties, some of the messages I receive mean
traveling several miles then paying a relatively hefty fee to gain
access to the Internet, plus knowing a foreign language. But it all
goes to show that man really CAN fly... with a bit of help from his
friends.

-R.S.Hoover

PS -- A regular 10" upholstery needle has a diameter of 0.0975" And
yes, it can make its own hole :-)

PPS -- You can whip two strands of thread together without causing any
problems. But if you want more, it's best to spin them together in
the manner used to make a rope. You can find examples of how to do
this on the Internet.

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