Home Techniques How to Make REALLY Small Kites that REALLY Fly!
Members

How to Make REALLY Small Kites that REALLY Fly!

 

Introduction

Small kites, especially ones that both fly well and are attractive to look at, have a special charm.  Even though kites of this type are now commercially available, making one yourself is still the best way to get one.  As with other special kites, these small kites require unusual materials and construction techniques, but the finished product is well worth the extra effort.

Size

How Small is Small?

The word small is relative, of course, but for the sake of this article a kite of less than 12 in. (30 cm) is considered small.  A kite that is 12 in. to 10 ft. (3 m) is considered medium-size, and a kite over 10 ft. is large. 

 

The materials and construction methods that are suitable for one size of kite almost never work if the plans are reduced or enlarged by a significant amount.  However, just about any kite plan in the medium-size range can be made to fly in small and large versions.  For example, if a medium-size kite is capable of flying without a tail, the small-scale version, if properly built, can also be made to fly without a tail.  I have made miniature versions of the delta, Eddy, Nagasaki hata, rokkaku and even the wedge kite, and all fly without tails. 

 

The kites described in this article are all about three inches in size, but some have been made to fly successfully as small as 1 3/8-in. on a 25-ft. line out of doors (though a five-inch tail was necessary). The techniques in this article are those I use and recommend, but I’m sure there are other – possibly even better–  techniques to be explored. 

Weight

The most important thing is weight!

  1. Use the lightest materials available.

  2. Use no more material than is necessary.

  3. Keep them LIGHT!

For any kite to fly it must generate lift.  The amount of lift must be great enough to support the weight of the kite and its flying line.  At some minimum wind speed, a kite will just barely rise above the horizontal.  If we add just a bit more weight to the kite, it will require more wind to stay up.  For a kite to fly in as low a wind as possible, its total weight (spars, sail and flying line) must all be kept as light as possible, while still being able to see and handle the small parts without damage. 

 

Sail Loading

One of the important elements involved in getting a small kite to fly well is to achieve a low enough sail loading.  Sail loading relates how much the kite weighs to the amount of projected area that must lift it.  If you know how much a kite weighs, you divide that by the area that is providing lift.

 

Projected area refers to the amount of area you would measure if you projected the kite in silhouette from down its line in flight.  Side panels that exist in the plane of the flying line, such as the keel of a delta, provide no vertical lift and are not included as lifting surface.

 

Most kitefliers are only familiar with kites in the medium-size range of one foot to 10 feet.  Typical kites at the top end of this range will have a sail loading of about two ounces per square foot.  Kites at the middle of this range will usually have a sail loading of about one once per square foot.  At the bottom end of medium-size you might go to a quarter-ounce per square foot.  These sail loadings represent average values: a good flying tailless kite might have a sail loading of half of these.

 

But when you get to small kites, such as a three-inch Eddy that can fly without a tail, you can look for a sail loading of a mere 0.01 ounce per square foot.  A kite with this low a sail loading is able to stay aloft in “winds” of less than one mile per hour. 

 

Materials

 

The availability of suitable materials has always been important in the development of kites.  Because paper and silk evolved in China and bamboo grows there, it is not surprising that kites were made from these materials over 2,000 years ago.  Even today, these materials are used to make beautiful kites with good flying performance. 

 

In recent years, plastics and other “high-tech” materials have been developed that permit us to make stronger and lighter kites.  And for successful small kites, the materials should be very light indeed, well under what would be considered suitable for kites that fly outdoors, even in low winds.  You need to find light weight materials for all parts of your kite:  spars, sail, flying line, reel, and storage container. 

 

Spars

While bamboo and wood are adequate for medium-size kites, and fiberglass and filament-wound epoxy tubing work well in large and high-wind kites, these materials fall short when it comes to small kites.  You need spars that are extremely small, light, and strong.  You can cut down on weight by getting the cross-section small enough, but it is very difficult to split wood or bamboo into long, straight and uniformly thin strips.

Another material used by some kitemakers is thin nylon monofilament (paintbrush bristles, for example), which is very flexible for spars. 

 

Preparing the spars:

Use the sizes in this table as a guide for cutting your spars the proper length.

 

Kite Height

Vertical Spar

Horizontal Spar

1 ½ - 2 inches

.006 inches

.004 inches

2 – 3 inches

.010 inches

.008 inches

4 – 6 inches

Bamboo

0.15 inches

 

       Bamboo: 

 

While bamboo is one of the best materials for kite spars, it is difficult for most people to split it down to small enough sizes to use.  A bamboo spar about 1/32-in. square is about as big as you’d want it to be and in the case of a very small kite (less than 2 inches) this would be far too big.  For some kites that require the vertical spar to be about 4 inches or more in length, bamboo is the best material.

Nylon paintbrush bristles:

You can use nylon paintbrush bristles for the spars.  It is available in a wide range of diameters and is easy to cut. 

      Fish line: 

 

Monofilament fish line can be bought, by the spool, in a wide variety of sizes.  A spool will probably be good for thousands of kite spars. The nylon fishing line has one disadvantage:  the line, as it comes off the spool, retains the curl.

             Selecting a size of fish line: 

 

The size line you use depends on the size of the kite and the strength of the wind you expect to fly the kite in.  Most small napkin kites won’t fly in a wind over 8 to 10 mph.  The table above gives some approximate spar sizes to try for your first experiments.  If you find the first size you try is too weak, you can glue another spar on the sail to provide added stiffness.

Straightening the fish line:

To straighten nylon fish line, all you need to do is wrap it around a board under tension and heat it in a conventional oven (not a microwave) at 250 degrees Fairenheight for at least an hour and then let it cool. 

1.      The board should be 1/2-in. thick or more so it won’t deform. 

2.      It should have a way of securing the ends of the line.  A loop in each end of the fish line around the head of a wood screw is an easy method. 

3.      A board 8 to 12 inches long will be big enough to allow at least two spars to be made from each piece of line.  A width of 3 to 6 inches allows several winds, for a good stock pile of material. 

4.      After the nylon has been heated and cooled, you can cut the nylon off the board with an X-acto knife or razor blade (put cardboard between the line and the wood block before cutting). 

5.      Wrapping tape around the center of the board will keep the nylon line from getting tangles after cutting. 

6.      The pieces that go around the ends of the board will fall free after cutting on both sides of the board. 

7.      Wire cutting pliers can also be used to cut off the end pieces.



Setting a dihedral: 

Just as heat can be used to straighten the fish line spars, it can also be used to put a permanent set for the dihedral angle.  The tip of a mini-hot glue gun is just about right to heat the line.  It softens the nylon slightly so it can bend, but not so much as to melt it into pieces or have it stretch if it is under tension, as happened when I used my 30 watt soldering iron.  A voltage control to limit the power of the soldering iron would solve this problem.

 

Sail or kite skin

The sail you choose for your small kite can be critical to its success.  Unless you have a delicate beam balance to weigh the sail material, it is difficult to check it.  Even micrometers are too coarse for measuring the very thin films. 

 

The following table gives a comparison of some weights and thicknesses for a number of materials. 

 

Material

Thickness

(in.)

Weight

(oz. per sq. ft.)

Tyvek ® Type 10

.004

.139

Plastic trash bag

.001

.080

Tissue paper

.0014

.059

.5-mil. Mylar ®

.0005

.059

Frozen food bag

.0004

.040

Condenser paper

.0002

.014

.06-mil. Mylar ®

.00006

.007

 

One of the best materials is 0.06-ml Mylar, which is light and flexible primarily because it is very thin.  However, Mylar has two negative characteristics.  Since it is so thin, it has far less strength than most films and will tear easily once a rip has started.  Also, very thin Mylar sticks to itself because of the static charge and can cause some unique handling problems that you don’t have with paper or thicker plastic.  To keep the Mylar flat while you work on it, you will have to use some building techniques that are radically different from what you may be used to. 

 

Adhesives

 Contact or rubber cement:  If you are using Mylar film as recommended for your small kite’s sail, you will have trouble getting most adhesives to stick to it.  Contact or rubber cement will work with most plastics, but they are generally too thick for our use and will need to be thinned down.  We do this to avoid adding unnecessary weight and to make application easier.  Five to 10 parts thinner to one part glue works well on spars and thin film sails. 

 

White glue:  The various brands of tacky glue sold in craft and hobby shops makes a good adhesive.  It seems to have a rubber base, sticks to nearly everything and remains flexible when dry.  The glue is a bit thick and works better if it is diluted with 10 to 20% water.  The thinned glue is easier to apply and remove excess glue. 

 

Flying Line

Standard string is easy to handle and use, but it has far too much weight for a small kite to lift.  Monofilament fishing line can be obtained in one-pound test strength, but its diameter is just under 0.004 in. and it is a little on the heavy side.  It is just slightly lighter than “invisible” sewing thread, which is commonly available in sewing stores. 

 

The flying line required by these kites doesn’t have to be very strong.  A thin sewing thread will work just fine.  A breaking strength measured in ounces rather than pounds would be more than adequate.  Another characteristic of some importance for small kite flying line is the line visibility.  If more than a few feet of line are out, the line is hard for spectators to see and they could accidentally damage or destroy the kite.  To fly the kite with a fairly long line, say 10 ft. or more, the weight of the line and its drag can be significant.

 

If ready availability is more important than peak performance, some stores with sections for sewing materials sell small spools with 30 ft. of thread packaged on a card.  The cards could contain 24 to 50 spools in assorted colors.  If the small spools are used, it’s helpful to make the notch that holds the end of the thread with a metallic marking pen so the notch can be found.

 

Silk thread, as it normally comes on a spool, is also a bit heavy, but it is possible to take a piece of it and untwist the silk into smaller fiber bundles.  With the help of good eyes, adequate lighting, a contrasting background and much patience, you can further untwist each of these smaller bundles to give perhaps six to 10 much smaller fibers.  And since small kites fly on lines just two or three feet long, you don’t really need to do a lot of separating.  Several short lengths of silk can be joined together to make a longer flying line.

 

Some kite lines are made up of bundles of very thin polyester fibers with no twist that can be pulled out of a bundle singly.  The one trouble with this type of line is that it is so fine, perhaps 0.0002-in. in diameter, that it is often difficult to see.  Not only is it hard for you, the kite builder and flier, to see, but spectators usually won’t realize that a line is there and will walk right into it.

 

Reels

Each small kite should have its own flying line and reel.  It is too much trouble to reconnect the line each time you want to fly a different kite.  The extra attaching knotwork also adds extra weight.  The reel doesn’t have to be very large because so little line will be stored on it.

 

A suggestion for a very simple reel:  Make it from a piece of 1/8-in. thick expanded polystyrene (from one of those foam trays that hold meat and fruit in the stores).  A 3-in. x 1-in. reel is a good size to start with, but it should be able to fit into the container that stores your small kite.  A skewer of bamboo about 1/16-in. in diameter and about three inches long placed in the center of the foam will give you something to hold when reeling line.  A hole for the bamboo can be made in the foam using a long sewing needle.  After it is in place, the bamboo can be glued to the foam with white glue.

 

Storage Containers

Because small kites are so light and fragile, they should be stored in suitable protective containers when they are not being flown.  Start looking early for your container, which can be cardboard, wood, metal, or plastic as long as it is big enough to hold the kite and reel, and is relatively airtight.  Clear plastic boxes are nice because you can see exactly what is inside them.  More than one kite can be stored in a box.  It is advisable that some means be used to hold the reel in place to prevent it from damaging the kite.

Last Updated (Monday, 15 February 2010 16:26)

 
Search MKG
Tip of the week
When flying a miniature kite indoors using a flying rod, move the tip in a figure eight going slightly faster on the outside of the loops.