Suggested material is lightweight ripstop nylon. For the prototype parachute that I constructed, I simply used a nylon shower curtain, which was nearly ideal, the only drawbacks being it was not ripstop and that it was somewhat heavier fabric than was necessary. It had a nice tight weave, not surprisingly, since it's intended purpose dictates that it be water-resistant! The following table lists the specifications for commercial parachute fabrics, as well as for the fabric that I used for the prototype parachute:
WARP | FILL | THICKNESS | TEARING | BREAK | AIR | |||
---|---|---|---|---|---|---|---|---|
MIL | WEIGHT | COUNT | COUNT | STRENGTH | STRENGTH | PERMEABILITY | ||
CODE | TYPE | (oz/sq.yd.) | (per in.) | (per in.) | (in) | (lbs) | (lbs/in) | (CFM/sq.ft) |
498E | D | 0.88 | 90 | 90 | N.A. | 2.5 | 40 | 300-500 |
498E | G | 0.88 | 90 | 90 | N.A. | 2.5 | 40 | 100-325 |
7020H | I | 1.10 | 120 | 120 | 0.003 | 5.0 | 42 | 80-120 |
7020H | II | 1.60 | 120 | 120 | 0.004 | 5.0 | 50 | 100-160 |
44378 | I | 1.17 | 126 | 132 | 0.003 | 5.0 | 45 | 0-5 |
* | * | 1.81 | 80 | 100 | 0.004 | N.A. | 47 | N.A. |
* IKEAtm, Billingen shower curtain (white) or Rosanna (off-white), 180x200 cm.; p/n 17763 (Billigen), 14331 (Rosanna), $14.50 CAD (sufficient fabric to make two 1-metre diameter canopies). Fabric for both is identical (100% nylon). The latter has a water-repellant coating, but this can be eliminated (before dyeing) by washing the fabric in hot water with laundry detergent. Properties listed for this fabric were determined by measurement and/or testing.
One half of the quantity of fabric that was used to make the canopy was dyed red. The dye used was:
The type that I used was braided nylon cord, the kind that is sold in the camping department of stores. The specific type that I used was:
The approximate width and thickness of the cord, measured under light tension loading, are :
and the cord tested breaking strength is:
The thread that was used for machine stitching the canopy together and for sewing the shroud lines to the canopy was the following:
The measured diameter, and tested breaking strength of the thread are:
The seam binding that was used to join the canopy panels was as follows:
The measured dimensions and tested breaking strength are: