Date: Sun, 18 Jul 1993 23:54:18 -1000 From: engel@irisa.fr (Jean-Christophe Engel) Message-Id: <22dr0a$38d@irisa.irisa.fr> Organization: IRISA-INRIA, Rennes, France Subject: Paneling Advice needed/required/sought Hello everyone, I'm about to start building my first ripstop kite, more precisely a clone of a Phantom. Each wing is made of three triangular panels: 1. a central panel, vertical side along the spine, one side along the leading edge 2. a side panel at the tip of the leading edge 3. an intermediate panel joining the previous two Each panel has an edge adjacent to the leading edge of the kite. (Hope you get the idea; see ASCII picture below ...) Wingspan is (approx.) 240cm, Height ~110cm, leading edge ~160cm I have some small pieces of ripstop of different weight, (ie g/m2) unfortunately I don't know the absolute values: I can only tell which is heavier ... Now my questions: 1. Where is it best to place the heaviest/strongest ripstop panel: close to the nose and spine (panel I), close to the tip (panel II), or inbetween (panel III) ? 2. More generally, what is the ripstop weight commonly used in building kites ? 3. Since I only have small pieces of ripstop, I may have to divide my panels into smaller parts. I imagined to divide panel #1 in two right-angled triangles (1top and 1bottom, see picture), but this would make a horizontal seam (_____ on the picture), a little below the upper spreader. Would'nt this horizontal seam (badly) modify the shape of the sail in flight, thus degrading it's flynig performances ? Any advice/comment ? ^ /|\ / | \ / | \ / 1top | \ /________|________\ / \ | / \ / \ 1bot | / \ / \ | / \ /_ 2 \ | / 2 _\ / - _ \ | / _ - \ / 3 ____- _ \ | / _ -____ 3 \ /____---- - _\ | /_ - ----____\ \ | / \|/ V ^ |____ vertical spine -- Jean-Christophe Engel, IRISA Rennes, France e-mail: engel@irisa.fr, Tel: +33 99 84 73 43 = = = = = = = = = = = = = = = = = = = = = = = = = = = = = = = = = = = = = = = Date: Mon, 19 Jul 1993 05:59:01 -1000 From: sasaki@das.harvard.edu (Marty Sasaki) Message-Id: <1993Jul19.155901.11971@das.harvard.edu> Organization: Harvard University Subject: Re: Paneling Advice needed/required/sought In article <22dr0a$38d@irisa.irisa.fr>, engel@irisa.fr (Jean-Christophe Engel) writes: >I'm about to start building my first ripstop kite, more precisely a clone of a >Phantom. Each wing is made of three triangular panels: stuff deleted >1. Where is it best to place the heaviest/strongest ripstop panel: close to the nose > and spine (panel I), close to the tip (panel II), or inbetween (panel III) ? I don't know that it makes any difference with different weights/strengths of fabric panels. I've made kites with polyester and nylon panels of different weights with no ill effects. >2. More generally, what is the ripstop weight commonly used in building kites ? Most kite makes use 3/4 ounce ripstop nylon. Icarex polyester is strong enough that many are using it in 1/2 ounce weight. >3. Since I only have small pieces of ripstop, I may have to divide my panels into > smaller parts. I imagined to divide panel #1 in two right-angled triangles > (1top and 1bottom, see picture), but this would make a horizontal seam (_____ > on the picture), a little below the upper spreader. > Would'nt this horizontal seam (badly) modify the shape of the sail in flight, > thus degrading it's flynig performances ? The folks who make the various forms of the Phantom say that the shape of the panels and the layout of the grain is very important for the performance of the kite. I know that with the Katana, the layout of the grain can make a very noticeable difference in the way the kite flys. I would suggest that you just try it and see. Compare your kite to a "real" phantom and report to the net the differences, if any. -- Marty Sasaki Harvard University Sasaki Kite Fabrications sasaki@noc.harvard.edu Network Services Division 26 Green Street 617-496-4320 10 Ware Street Jamaica Plain, MA 02130 Cambridge, MA 02138-4002 phone/fax: 617-522-8546 = = = = = = = = = = = = = = = = = = = = = = = = = = = = = = = = = = = = = = = Date: Mon, 19 Jul 1993 05:59:01 -1000 From: sasaki@das.harvard.edu (Marty Sasaki) Message-Id: <1993Jul19.155901.11971@das.harvard.edu> Organization: Harvard University Subject: Re: Paneling Advice needed/required/sought In article <22dr0a$38d@irisa.irisa.fr>, engel@irisa.fr (Jean-Christophe Engel) writes: >I'm about to start building my first ripstop kite, more precisely a clone of a >Phantom. Each wing is made of three triangular panels: stuff deleted >1. Where is it best to place the heaviest/strongest ripstop panel: close to the nose > and spine (panel I), close to the tip (panel II), or inbetween (panel III) ? I don't know that it makes any difference with different weights/strengths of fabric panels. I've made kites with polyester and nylon panels of different weights with no ill effects. >2. More generally, what is the ripstop weight commonly used in building kites ? Most kite makes use 3/4 ounce ripstop nylon. Icarex polyester is strong enough that many are using it in 1/2 ounce weight. >3. Since I only have small pieces of ripstop, I may have to divide my panels into > smaller parts. I imagined to divide panel #1 in two right-angled triangles > (1top and 1bottom, see picture), but this would make a horizontal seam (_____ > on the picture), a little below the upper spreader. > Would'nt this horizontal seam (badly) modify the shape of the sail in flight, > thus degrading it's flynig performances ? The folks who make the various forms of the Phantom say that the shape of the panels and the layout of the grain is very important for the performance of the kite. I know that with the Katana, the layout of the grain can make a very noticeable difference in the way the kite flys. I would suggest that you just try it and see. Compare your kite to a "real" phantom and report to the net the differences, if any. -- Marty Sasaki Harvard University Sasaki Kite Fabrications sasaki@noc.harvard.edu Network Services Division 26 Green Street 617-496-4320 10 Ware Street Jamaica Plain, MA 02130 Cambridge, MA 02138-4002 phone/fax: 617-522-8546 = = = = = = = = = = = = = = = = = = = = = = = = = = = = = = = = = = = = = = = Date: Tue, 20 Jul 1993 08:29:53 -1000 From: sasaki@das.harvard.edu (Marty Sasaki) Message-Id: <1993Jul20.182953.28997@das.harvard.edu> Organization: Harvard University Subject: Re: Paneling Advice needed/required/sought In article <1993Jul20.130732.5740@aber.ac.uk>, puc@aber.ac.uk (Paul Crowley) writes: >On a similar note, does anyone have any tips on how to sew up the >panels to give a taut trailing edge? My self-built phantom is >incredibly noisy and flies a little slower than commercial versions >so I'd like to modify it if possible. I've just tried flexors a la >scorpion with some success - less noise, smoother flight, faster >turns and greater stability at the wind edge. Generally, keep the grain parallel to the trailing edge. A straight edge is inherently noisier than a curved one. Most kites will benefit by the use of outboard standoffs or "flexors". Some kites do use binding on the trailing edge and also run a line, often made of Kevlar, along the trailing edge. Dean Jordan uses multiple layers of fabric along the wing tip. The curved trailing edge is easy to do, once you get the hang of it. The Katanas have a curve near the wingtip. Practice sewing large radius curves first, then smaller ones until you get to the size that you need. -- Marty Sasaki Harvard University Sasaki Kite Fabrications sasaki@noc.harvard.edu Network Services Division 26 Green Street 617-496-4320 10 Ware Street Jamaica Plain, MA 02130 Cambridge, MA 02138-4002 phone/fax: 617-522-8546 = = = = = = = = = = = = = = = = = = = = = = = = = = = = = = = = = = = = = = = Date: Tue, 20 Jul 1993 03:07:32 -1000 From: puc@aber.ac.uk (Paul Crowley) Message-Id: <1993Jul20.130732.5740@aber.ac.uk> Organization: University of Wales, Aberystwyth Subject: Re: Paneling Advice needed/required/sought In article <22dr0a$38d@irisa.irisa.fr> engel@irisa.fr writes: > >Hello everyone, > >I'm about to start building my first ripstop kite, more precisely a clone of a >Phantom. Each wing is made of three triangular panels: > > 1. a central panel, vertical side along the spine, one side along the leading edge > 2. a side panel at the tip of the leading edge > 3. an intermediate panel joining the previous two > > >Now my questions: > >1. Where is it best to place the heaviest/strongest ripstop panel: close to the nose > and spine (panel I), close to the tip (panel II), or inbetween (panel III) ? > >2. More generally, what is the ripstop weight commonly used in building kites ? > >3. Since I only have small pieces of ripstop, I may have to divide my panels into > smaller parts. I imagined to divide panel #1 in two right-angled triangles > (1top and 1bottom, see picture), but this would make a horizontal seam (_____ > on the picture), a little below the upper spreader. > Would'nt this horizontal seam (badly) modify the shape of the sail in flight, > thus degrading it's flynig performances ? > Any advice/comment ? > > > stuff deleted >Jean-Christophe Engel, IRISA Rennes, France >e-mail: engel@irisa.fr, Tel: +33 99 84 73 43 On a similar note, does anyone have any tips on how to sew up the panels to give a taut trailing edge? My self-built phantom is incredibly noisy and flies a little slower than commercial versions so I'd like to modify it if possible. I've just tried flexors a la scorpion with some success - less noise, smoother flight, faster turns and greater stability at the wind edge. However, there is a (small) weight penalty and the flexors dont look pretty. Has anyone tried edge binding the trailing edge rather than hemming? How would the addition of a length of cord affect performance? Lastly, how do manufacturers such as Rare Air cut a curved trailing edge and keep it tight? Thanks, Paul (puc@decb.aber.ac.uk or puc@aber.ac.uk)