Sewing Tips for the NPW’s
Because
there is so much linear sewing on the NPW, I use a serger [also called overlock
machines] for the long linear runs. Sergers are VERY fast and make strong
seams. And, using a “Cording Foot”, I
sew on a 200# Dacron fishing line after "Welding" or
"Hot-Cutting" the seams together.
Doing this first saves a step in construction. This “Leech Line",
as I call it, adds a tremendous amount of strength to the seams where used. It
serves mainly as an anchoring for the bridle or shroud lines, and I use it at
the sides of, and behind the center panels, as well as the entire perimeter of
all the NPW kites. It also eliminates
the tedious folded loops.
I think I get the best of both worlds using both the serger and the
regular sewing machines together, too. (Used Sergers can be VERY reasonably
priced, and found on eBay, too. You'll use a bit more thread, but the price of
serger thread is VERY reasonable, once again, on eBay. Well… thousands of yards
on one cone can last a lo-o-o-o-ng time, but watch
the quality. Fuzzy [cheap] thread can
cause a lot of problems.)
Now….. If you don't have a
walking foot on your machine the lengthy seams can get out of alignment as you
sew, and you can get a lot of puckering by the time you get to the end of the
seam. [A walking foot feeds the material
from both top and below simultaneously keeping it solidly together and from
slipping over or past one another,] By
Hot-Cutting the panels together, it eliminates this potential crawling problem. It also eliminates the need of a walking foot
or sticky glues or tapes. The pix below might give a little better idea of how
I manage to make the long runs and get the leech line sewn in all in one pass
after hot-cutting. The finished product (serger seam), to some, might be a bit
rough and unfinished, but I am not interested in sewing contests or the pure
artistic aesthetics of sewing. I just want to have a strong seam and get into
the air as soon as possible.
As I mentioned earlier, I don't make the sewn in loops like most NPW
directions call for. They are, IMHO, a royal pain in the ass to make and sew
in!! My machine just has a tough time
punching through some 6-8 or more layers of material, and the sticky crap it
leaves on the needle- well, it just isn't worth the effort.
For
Example, try this method, [especially if you can get your hands on a cording
foot for your machine, serger or not…]
1.
Hot-cut
using a knife edged soldering iron to cut out the panels to size, not allowing
for seams.* I
make my templates and cutting guides out of Formica. Very inexpensive from cabinet shops when
purchased as scrap.
2.
Next
hot cut (melt-weld) the panels together removing only about 1/16” or 2mm of
material to make the “weld.”* [ Pix 1 & 2
below.] Be sure the fronts of the panels
face one another.
3.
Handling
very carefully, sew or Serge** the panels
together using a "Cording" foot and 200# or 100Kg cord or line if you
have one. [Pic 3]
4.
[OPTIONAL!]
Sew the backside hems down flat on the back.
Use the longest and widest zig-zag stitch you can… [ Pic 4]
5.
Cut
out and sew all of the darts.
6.
Using
more 200# line, serge or sew on the perimeter line all the way around the
kite. There are several methods to do
this, and I, once again prefer the serger.
7.
You’re
DONE with the sail!! [I usually toss the
finished sail into the washing machine before bridling and after putting on the
“T” ties.]
* I
don't figure for extra material for seams when using the serger- It doesn't
seem to make an appreciable difference in the final outcome in size of the
sail, overall. A 1/4" seam or two
in a 6 foot tall sail?!! C'mon... get
real!! [That's less than 1/2 Cm in 2
meters to the guys in
** Sergers leave about a 3/16" seam, or
"flap" [equating to about a quarter inch, total material loss on each
seam] on the back side of the sail after stitching. I don't like flapping or loose
"things" on the backside of my kites.
I like to anchor the seam/flap by folding it over and covering the
visible cord, and sewing it down with a regular sewing machine. Make the pass over the flap using the longest
stitch possible with a medium zig-zag stitch setting. Try to get the needle
into the cord with at least one side of the zig-zag stitch, thus better
anchoring the cord
For cording, or leech line, use whatever suits YOU. Abandoned
"Black Death" flying line from those Rok battles? Nylon braided sash
cord? Most any BRAIDED line or cord will work, the bigger the NPW, the bigger
the line you can use. For some NPW's, I
use parachute cord all the way around the perimeter, just sewing it to the edge
of the sail. Parachute cord is available
in several different colors: http://www.vtarmynavy.com/parachute_cord.htm
sells the stuff in the states, and I know there’s a good supplier in the
There are some schools of thought about
too many punctures on ripstop and that it can act like perforations to promote
"continued tearing along the dotted line"... I haven't
had ANY troubles with it for some 5 years of flying all sorts of different
kites, and the sails aren’t even RipStop Nylon [RSN]! I don't extreme buggy, or jump either. Once
again, it's up to you.
I do, however, tend use the more commonly
available Nylon materials for my sails far more often than RSN. The specific material I refer to is called
Suiting or Coat Lining. You’ve ALL run
into it one time or another. Men’s dress
coats are lined with it and better women’s suits are, too. The ladies suiting has a far nicer selection
of colors, altho’ most are pastels, and not really brite. That’s the trade-off. The stuff can come in many different weights
and porosity… even open weaves… but it ALL works, even the open weave
stuff. I have a HUGE 10M^2 - the eNPW5
Giant Killer Bee - that I made almost entirely of a suiting that looks almost
like chiffon. The pull is considerably
less than it would have been using standard tightly woven nylon materials, and
I’m glad I made it that way!!! Even so,
it’s still hard to control in 4-5 mph winds with 24” handles! It IS and exercise machine.
Don’t be hesitant to try/use alternative
materials. With some RSN’s approaching
$12
HERE’S HOW…
First cut the material as shown below
Steel
strapping isn’t necessary. Use whatever
will hold the Formica (plastic counter-top material) down.
After
cutting, carefully transfer the two panels to the sewing machine or Serger and
start sewing!!
When serging, I don't let the cutter take
any excess material off (pic 3). I feel
that the welded seam where the material joins together acts as an anchor that
won't allow the material to fray or unravel inside the overlock stitch. And if you use a regular machine to sew the panels
after hot-cutting, you don't need a walking foot as the seams are still well
fastened together. No creeping!
If you use a standard machine to attach the leech or parachute line, use
a wide zig-zag stitch letting the needle go OFF of and outside the edge of the
material on one side. The same applies
to 200# cord as well. This creates a
series loops around the outside of the welded seam adding to the strength. The stitches per inch should be in the 10-12
range, and the stitch width wide enough to easily accommodate punching through
the Dacron line on ONE side of the stitch.
Once this is done, fold over the resultant flap on the back-side of the
sail, and zig-zag as shown below (pic 4) and from the front side (pic 5).
Turn your sail over and finish up by stitching the resultant flap down
(pic 4).... Note the cord under the seam above (pic 5). Again- make sure one side of the zig-zag stitch catches,
or penetrates the Dacron leech line.
This type seam offers both a strong seam AND attachment points for
bridling. Note which side of the center
panel the seams are on when you do stitch down the flap… they can both end up
on one side or the other and not opposing one another!
I have never regretted buying the serger as the savings in sewing time
has just been phenomenal. Flattening the
"flap" on the backside is a lot cleaner looking seam IMHO. It's not a necessity to do it if you don't
have the inclination to do so. Many commercially made kites are made using
sergers, and they certainly don't take the time and effort of sewing the
flaps down flat!
As an aside; I'm not really
familiar with other serger type sewing machines, but I'm learning. The model I
have is a used White Superlock 534. I paid $50 for it at a local sewing shop
and, luckily, it's in great shape!! The gal there was quite willing to take
about a half-hour and give me a thorough run-thru on it when I bought it. (She
was quite surprised encountering a guy who knew how to sew, let alone wanting a
serger, too! Now I wished I could find a
Pfaff 1222 at a decent price!!)
My serger machine already had a hole in the front of the foot that
allows the passing through of the cord (Dacron line and whatever else will pass
thru the hole!) This is often called a "cording" foot or
"piping" foot. I hang the
spool of 200#, or whatever test Dacron line above the machine on a dowel well
above the working area. It turns freely and never has given any trouble as the
serger has plenty of pulling power.
Some may want to crowd the stitch around the length or perimeter of the
kite. (A serger can make lots more stitches per inch. It’s sometimes used for rolling the edges of
napkins, for instance.) By making the thread a lot closer together, the looks
of the outside edges are considerably less ragged looking. I have sewn one kite
around the outer perimeter so tightly that it looks almost like it has bias
tape around it.
Again ~ Many kite makers think this is a sin.
The mainstream opinion is a tight, or close stitch
will weaken the fabric considerably. Well, that may be, but none of my suiting
seams have "ripped along the dotted line" as yet, and I've put my
first and subsequent kites through some pretty tough maneuvers for the last 5
years. And that same kite has put ME through a
NOTE: I have never used the serger on RSN, and it’s properties might well be totally different as to the
perforations being close together. If and when I do… I’ll definitely open the stitch per inch
feature to the widest setting.
I hope this helps get you in the
air a lot sooner and easier. If you've any questions just gimme an email and I'll
try and help if I can. Now check out the Bridling section for a quick and
simple method of making 4 shrouds at a time, not one.
A pic of your finished kite in the
air would be nifty to add to my gallery of NPW's, if you would.
Bill Painter- Phoenix, Az. NPWBill@cox.net
May
the wind always BE at your back!!