So I have been working on and off on this 1.5 meter diameter parachute for a while now. It's been a great project and I have learnt loads especially about sewing machines! It's designed to be the correct size for my Level 2 certification rocket I am currently constructing. The parachute is designed with 16 "gores" or panels which are hot cut using a soldering iron.
flat felled seam but cut the inner and outer edges to be the designed size with no seam. I think that this is strong enough but I am interested to make another and experiment with adding binding to the edges as I have seen this done on some ex military parachutes I own.
Above showing the stage with all the inner diameter lines sewn in on the machine. I just used 2mm braided nylon for this build as I had some and its quite cheap which is important when you use about 45 meters in this construction. Now that I have worked out some design issues etc I will probably make another at some point and use a higher quality material for the lines.
Above is the first test inflation on a luckily breezy day. The geometry/shape of the annular design when inflated actually results in a much higher drag coefficient than other parachute designs which seems counter-intuitive particularly when you consider the huge hole that they have in them! Finally, massive thanks to my parachute making mentor BJ Gray of Bama Recovery Systems, who I heartily recommend if you want to purchase a very high quality parachute made by a true master of the art.