Circular Nylon Parachute

If a job is worth doing, it is worth doing well and making a circular nylon parachute will give you skills in cutting and sewing nylon as well as a good quality chute that will last (you can wash this one if you really want to).

Materials and equipment

For this parachute (and its drogue), you will need . . .

• four feet of nylon fabric (be adventurous - go for bright red);
• a reel of thread of the same colour;
• a glue stick;
• around 20 metres of light nylon cord;
• a mug of cold water;
• a soldering iron;
• a small open flame (like a candle);
• a sewing machine;
• 2 plastic rings (about 2cm diameter); and,
• 0.3m elastic cord.

Shroud

Lay the nylon fabric on the floor and then pick it up from a point that is halfway between the sides that are closest together and the same distance from one of the other two sides (where the green lines cross on the diagram). By doing this, you will get the largest area (outlined in blue) and have the most spare to make a drogue chute.Mark this point with a cross.

Then, use a piece of string, the same langth as your radius, to mark out sixteen points at equal intervals (on the imaginary blue line). Then, join them by drawing a straight line with a pen, using a ruler to make a regular, sixteen sided polygon. At each of the sixteen points, make sure that the line that you have drawn, extends around 1" towards the centre of the shroud. Next, put a mug in the centre of the shroud and draw around it. You now have a polygon, marked in ink and ready to cut.

Repeat the bove process on a smaller section - around 1.5 feet in diameter - for the drogue.

If you cut nylon with scissors, you will produce an edge that will fray given half a chance. Cutting nylon with something hot gives a good, seals edge that is very resistant to fraying - in addition, it is quicker and easier to cut nylon in this way.

Lay out the nylon shroud and run the hot soldering iron along the lines that you have drawn. If you make sure that the nylon is not in contact with a heat dissipating surface such as a metal sheet, it will cut quickly. If you press the nylon down so that it is in contact with a metal sheet, it will take ages to do it. When you have finished, you should have your main and drogue chutes ready to sew.

Sewing nylon is not as bad as it sounds. The main problem is that it does not stay folded and taking the normal course of action and using pins will lead to a time consuming drudge that will seem to take forever. On the left are the steps that you need to take to make a good seam for the centre hole in your nylon shroud. You should get your skills on this bit and the rest will be quite easy. Put the edge of the fabric on the sewing machine (it doesn't really matter which way around you work - these diagrams just show the way that I did it); Apply a smear of glue stick to around one or two inches; Fold over the edge so that just under the width of the seam goes over (around 2mm for the hole in the middle see how large the thread is in comparison to the width of the seam); Sew all the way around. Apply the glue and fold over as you go - even the glue won't hold it all of the way around; Once you have done a complete circle, apply glue again (to between one and two inches of seam); Fold over the length that you glued; and, Sew all of the way around doing a couple of inches at a time. You will end up with a double stitch on one side (picture) and single on the other. Tie off and you have your centre hole made.

Next you need to sew around the outside edges. Again, place the fabric on the flat bed of the sewing machine; Apply the glue-stick to one full length of the outer edge; Fold over - around 4mm this time; Apply another smear of glue-stick; And fold over again. Now you have a length of triple thickness nylon, glued together to form a double folded edge; Sew. Once you have completed one section, repeat for the other fifteen. Having completed the main shroud, you can repeat the process on the drogue chute. Having done that, soak the chutes in warm water for a few hours to get rid of the glue - doing this will make the seams more flexible.

Cords

Take the nylon cord and cut off roughly 2½ metres - placing this to one side. To the remainder, fold it in half, then in half again and so on until you have 8 lengths, just over 2 metres long. Cut it into these lengths and seal the ends by melting in a flame for a second or two and then putting the melted end into the mug of cold water (left). Instead of using a knife or scissors, nylon can be cut by putting it in a small flame thus automaticaly sealing the ends.

Take one of the eight pieces and fold in two, forming a loop. Thread the loop through one of the plastic rings and then pass the two loose tails through this loop. Pull tight, tie a knot (not to stop it from coming undone but just to provide a bit of resistance) and repeat for the other seven lengths. You should now have sixteen ends coming from one plastic ring. Then tie the elastic to the ring (as in the photograph) - tying a knot in each end so as to stop fraying.

Now, make a smaller one with six or eight cords around one foot long for the drogue.

Assembly

Place the plastic ring in the middle of the shroud and lay out the cords so that they intersect the edge of the shroud at the sixteen corners. Make sure that the cords are in the order that they are on the plastic ring as this will make it easier to sort out any tangles that you may get into later on in the field.

At each corner, pinch about 1cm of the seam and tie a knot around it very tightly. Then, just to make sure, tie another. In the picture (right), you can see that the end of each cord is also tied in a knot.

Repeat a further fifteen times and then perform the same task on the drogue chute.

On to the Pictures . . .

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