# Making Tetrahedral Kites

## Step-By-Step - MBK Skewer Tetra!

Very large tetrahedral kites are a pain to build and a pain to setup on the flying field. Easy but tedious. However, the more pain, the more gain as the sight of a huge complex tetra 'nailed to the sky' in a stiff breeze is awesome indeed!

If you want to just get started in this direction, without having to take too many pain-killers ;-) a good design to try is the 4-cell tetra. One of these can be made small enough so it fits neatly inside the boot of a modern car, fully ready-to-fly.

This kite likes moderate winds, but is still light enough to be affected by thermals. Just check out the video...

Although time-consuming, constructing tetrahedral kites is fairly easy to understand and carry out...

A triangular base of spars comes first. From each corner, another spar is attached, with all 3 of these coming together at the top. All spars are of exactly the same length.

Skewer tetra kite in flight

When all 4 vertices are securely joined, a sail is attached to 2 sides. Any 2 sides will do, due to the symmetry of the shape! This whole thing is 1 cell.

See if you can pick out the 4 individual cells of my skewer-and-plastic tetra in the photo up there on the right.

Oh, by the way, don't try flying a single cell - it simply will not be stable. 4 cells is the minimum!

In general, a 4 cell tetra is easily constructed by following these steps...

1. Make a single tetrahedral cell as described above.
2. Copy it to make 3 more cells.
3. Put 3 cells on a flat surface, in a triangular arrangement, so there are 3 points of contact between them. The sails should all be oriented the same way, and none of them should be lying flat on the flat surface!
4. Fasten the cells together at their points of contact.
5. Add the remaining cell to the top of the 3 connected ones, arranging the sail in the same direction as the others, and fastening the 3 points of contact.
Bridle detail

Lastly, attach a flying line and bridle so the arrangement looks like the photo over there on the right. Then go out to fly! However, unless the kite is super-light, it might need a fair amount of breeze to fly successfully. A very high proportion of the weight of tetrahedral kites is in the spars. Wait for a windy day, or put your running shoes on and tow it like an exuberant kid!

You might first have to settle on the exact materials and techniques you wish to use.

All sounds a bit hard?

Guess what, I'm going to show you the relatively quick and easy way to make a 4-cell tetra that loves light-to-moderate winds!

Try this Stake Line Winder from Amazon if you need some flying line. The 30 pound rated Dacron is good for a wide variety of small to medium sized kites. Anything with a span of 2 meters (7 feet) or more would be safer on heavier line.

## Tetras In Skewers And Plastic

Bamboo BBQ skewers are a great spar material for small tetrahedral kites, being very stiff and strong for their weight.

A cheap sail material is garden bag plastic. The thinnest, cheapest ones can be used, or you can use thicker brighter-looking plastic for more durability and perhaps better looks!

I decided to whip together a 4 cell tetra just for readers of this page! Using the cheapest bamboo skewers and garden plastic.

Here's step-by-step instructions on how to do it...

## Making A 4-Cell TetraStep By Step...

Compared to most methods for making tetrahedral kites, the following method is relatively quick and easy...

Take a 30 cm (12") bamboo BBQ skewer, and attach a length of clear sticky tape to one end as in the photo. The tape should be about as long as an average adult middle finger. The skewer is sitting on half the length of the tape.

Carefully roll the skewer in your fingers, attaching the width of the tape to it as you go. Then, keep rolling the skewer while drawing your fingers away from the tip, so the free length of tape spins itself into a tight cord. It should be pretty clear in the photo.

Attach tape to the other end of the skewer in the same way. Then do both ends of another 5 skewers!

Arrange all 6 skewers as in the photo, and note how the little cords of rolled-up tape overlap each other at the 3 corners of the large triangle of skewers.

Here's a close-up of one of those corners. The 3 little cords have been twisted together, then another short length of tape has been wrapped around the 3 cords several times. The 3 skewers are now joined securely at the tips.

Do the other 2 corners too!

Finally, draw those 3 free skewers up away from the floor, and secure the 3 tips together in the same way as all the others.

(Cue trumpet flourish...) Tada! A tetrahedron.

Take your tetrahedron and lay it on a sheet of plastic that you would like to use as sail material. Trace around the inside of the triangle that is in contact with the plastic. Use a black permanent marker pen.

Flip the tetrahedron over, along one side, without letting that side slip or change position. Now trace around the inside of the new triangle which is in contact with the plastic.

Finally, draw tabs in, next to 4 of the sides of the diamond shape you have drawn. See the photo. I was in a hurry, so just eye-balled it apart from ruling the longest straight lines in with a ruler! Just allow plenty of width to fold each tab over a skewer.

Next, cut all around the tabbed diamond shape with scissors.

The photo also shows a couple of the tabs folded over and stuck down with sticky tape. The tetrahedron has been flipped back to its original position.

Look at that! A complete cell, where the remaining 2 tabs have been folded over and stuck down.

Now make another 3 complete cells. Whew. I'll wait here while you create them all...

... finished?

OK, now arrange them as in the photo. All the sails should be facing the same way. At every corner point where the tetrahedrons touch, there should be 2 short sticks of tape. One coming from each tetrahedron.

Here's a close-up of one join between tetrahedrons. See how the sticky tape sticks point in opposite directions. Lay them side by side and wrap more sticky tape around the whole lot, using several wraps to make it strong.

Take a length of 20 pound flying line, about 2 skewer-lengths long, and attach it to the kite as shown in the photo. I just used Half-Hitches around the sticky tape at both points. Small tetrahedral kites such as this one do not require more than 20 pound line.

Also tie a small Loop Knot into the bridle, so the line angles are approximately as shown. The exact position is not as critical as for other types of kites. It should fly fine!

## Tetrahedral Kites From Straws

Yes, ordinary drinking straws, in either paper or plastic. Now that you know all about the details of construction, you should also be able to whip up a 4-cell tetra using straws instead.

One quite popular method is to feed a line through each of the 6 straws, leaving an ample amount hanging out each end of the straw. A simple 3-strand knot at each vertex keeps the whole structure rigid. Well, rigid enough for the purpose. The extra lengths of line at each vertex can be used to tie the vertices of several completed cells together.

Here's some ideas for those threaded lines:

• embroidery cotton
• light fishing line - could be fiddly!
• 10 or 20 pound kite line of any type

With use, the line can tend to cut into the ends of the straws and shorten the life of the kite.

One proven idea for plastic straws is to carefully melt each end of each straw, by touching it to a hot plate. Just enough to soften and thicken the wall of the straw a little, right on the end!

For paper straws, you could try a single wrap of narrow sticky tape around each end of each straw, for reinforcement. This would also increase the weight of the kite a little, but it's worth a try.

Regarding sail materials for tetrahedral kites, there are many options...

• wrapping paper
• rip-stop nylon (spinnaker cloth)
• rice paper
• mylar
• cellophane
• plastic bags
• builder's drop-sheet plastic

## Tetrahedral Kites - General Points

One thing to try, if you have the patience, is to connect four 4-cell tetrahedral kites together to form a 16 cell! It will fly more stable than the 4-cell, so should have a better wind range.

#### Out In The Field

Box kite stories of my real-life flying experiences are worth checking out!

Illustrated with photos and videos, of course.

This page hardly scratches the surface of this fascinating corner of the kiting world. Tetras can be tied together in an infinite variety of configurations, requiring complex bridles to match.

More durable tetras can be constructed from fiberglass or graphite spars and covered with rip-stop nylon sails like most retail kites. With sufficient spar thickness and stiffness, these kites don't need the full 6-stick tetrahedron cell construction. Instead, other forms of bracing can be used, which use far less spar material.

Making tetrahedral kites is an area that remains wide open to experimentation and new ideas! Perhaps you might end up inventing your own method. As I did, with .... skewers and plastic.

Try this Stake Line Winder from Amazon if you need some flying line. As mentioned earlier, this product is a good compromise for many small to medium sized single-line kites.

### E-book special of the month (25% off)...

This printable e-book takes you step-by-step through making a 120cm (4 ft) tall Parafoil kite. This 4-cell kite performs best in gentle to moderate wind speeds. That's 12 to 28kph or 8 to 18mph. Even in light winds, this kite will hang in the air, although at low line angles. In fresh winds, it pulls firmly for it's size, so small kids should only fly it while supervised!

Every kite design in the MBK Soft Series satisfies the following points...

• Materials are plastic sheet, tape and line – and nothing more!
• Tools are a ruler, scissors and a marker pen - and nothing more!
• All cuts are along straight lines.

For the greatest chance of success, I make recommendations regarding the materials. For example, the type/weight of plastic, type/width of tape and line type/strength. Close enough should nearly always be good enough, since the design is well-tested and should be tolerant of small differences from my original.

Get the e-book for making the MBK Parafoil kite. After making your first one in plastic and seeing how it performs, you can try soft Tyvek or rip-stop nylon for your next build.

The e-book is a PDF file - which means printable instructions to refer to while you make the kite. It also means convenient off-line access if that suits you better.

## What's New!

1. ### Flight Report:Multi-Dowel Rokkaku Dusted Off

May 26, 17 01:32 AM

Having flown nothing for a while and with winds rather light - or so I thought - it was off to a field in Noarlunga to fly the big 2.4m span Rokkaku...

Looking around, the trees weren't doing much so I…

Plenty of fun kite info, photos and videos - there's definitely too much here for only one visit! Feel free to leave your impressions of this site or just this page, below...

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Testimonials
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Very satisfying making your own and watching them get air-born for the first time."

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Wind Speeds

Light air
1-5 km/h
1-3 mph
1-3 knots
Beaufort 1

Light breeze
6–11 km/h
4–7 mph
4–6 knots
Beaufort 2

Gentle breeze
12–19 km/h
8–12 mph
7–10 knots
Beaufort 3

Moderate breeze
20–28 km/h
13–18 mph
11–16 knots
Beaufort 4

Fresh breeze
29–38 km/h
19–24 mph
17–21 knots
Beaufort 5

Strong breeze
39–49 km/h
25–31 mph
22–27 knots
Beaufort 6

High Wind
50-61 km/h
32-38 mph
28-33 knots
Beaufort 7