Date: Thu, 19 Jan 1995 06:07:15 -1000 From: peterk@wfw.wtb.tue.nl (Peter Kruijt) Message-Id: <3fm2nj$mbb@tuegate.tue.nl> Organization: Eindhoven University of Technology Subject: Kite making newbie asks stupid questions Dear Fellow kiters, I am making my first kite at the moment (the heavy duty from Neue Lankdrachen und Einleiner). There are some things I cannot quite figure out or not yet understand: 1. Are plans in general with or without seams? 2. This kite has dacron on the `bottom' (sorry for this, but I don't know what to call it correctly in english). Doesn't this make that the kite becomes noisier and less stable? 3. How important is symmetry? 4. How important is the weft? 5. Are there other important things one has to regard when making a kite? The bridle is, but are there some things one easily forgets or disregards? Thanks for your patience, Peter Kruijt (peterk@wfw.wtb.tue.nl) -- Peter Kruijt (peterk@wfw.wtb.tue.nl) Department of Mechanical Engineering Eindhoven University of Technology = = = = = = = = = = = = = = = = = = = = = = = = = = = = = = = = = = = = = = = Date: Thu, 19 Jan 1995 13:17:05 -1000 From: hayden1009@aol.com (Hayden1009) Message-Id: <3fmrth$gtj@newsbf02.news.aol.com> Organization: America Online, Inc. (1-800-827-6364) Subject: Re: Kite making newbie asks stupid questions Peter K. asks: >1. Are plans in general with or without seams? Depends on the plans, but when just dimensions are given, they are usually without the seam allowance. >3. How important is symmetry? Balance in the kite is important. symmetry is personal taste. >4. How important is the weft? In sewing in general the warp and weft is important, the warp being the stronger threads (will take more stress). In kites, the "straight of the goods" is important, the grain should run with the stress on the kite. Fabric on cross grain (diagonally) stretches. This could affect flight if the sail stretches where you don't want it to. Another important thing is stitch length (frequency). Small stitches close together (whether zig-zag or straight) is like adding perforations, which will tear under stress. A number of people I've talked to recommended no more than 6-8 stitches per inch. On the other hand, the most important thing in kite making is just doing it, starting, learning with your mistakes and going from there. And boy is it exciting when it actually flys. Alice Hayden 8^) = = = = = = = = = = = = = = = = = = = = = = = = = = = = = = = = = = = = = = = Date: Fri, 20 Jan 1995 05:48:25 -1000 From: Adrian Pierorazio Message-Id: Organization: Queen's University, Kingston Subject: Re: Kite making newbie asks stupid questions On 19 Jan 1995, Peter Kruijt wrote: > I am making my first kite at the moment (the heavy duty from Neue Lankdrachen > und Einleiner). There are some things I cannot quite figure out or not yet > understand: > > 1. Are plans in general with or without seams? If you are working with fabric, seams are very common as this is the way pieces are joined together. Although many 'flat' kites can be made without seams, it is often an inefficient use of cloth. Also, note that hems are used at all the outside edges to prevent stretch, improve strength, and reduce the possibility of fraying. > 2. This kite has dacron on the `bottom' (sorry for this, but I don't know what > to call it correctly in english). Doesn't this make that the kite becomes > noisier and less stable? As I am not familiar with the particular plan you are referring to, I will leave this question to someone else. > 3. How important is symmetry? Very (unless you're Istan Bodovsky (sp?)). If the kite is not symmetrical (and was designed to be), the kite will tend to fly off to one side of the wind. So what? Well, if the wind lulls, the kite will tend to turn towards the ground instead of keeping its nose in the air (ie. you will perform the 'premature landing at an unfavorable angle' trick otherwise known as the 'crash') > 4. How important is the weft? If you are using directionally reinforced material, the direction of the 'bias' of the fabric can be very important. Like most reinforced materials, ripstop nylon (and Icarex, Orcon, etc) is quite strong and dimensionally stable in the direction of the reinforcements (warp and weft in this case) but has a tendency to stretch significantly if force is applied at other angles. Again, what does this mean? This means that if the bias of the fabric is not symmetrical (even if the kite itself is), then one side will tend to billow more than the other and you will have a kite that flies off to the side again. Normally, you will align the fabric so that the reinforcing threads are aligned with the direction of the most force (leading edge, trailing edge, spars, etc) and, of course, its -always- a trade-off of where to line up the fabric. On the other hand, if you're using unreinforced material (silk, paper, plastic, etc) it's hardly significant at all. Check your material by pulling on it at various angles to see if it stretches the same way. > 5. Are there other important things one has to regard when making a kite? The > bridle is, but are there some things one easily forgets or disregards? Of course there are (literally) hundreds of books written about this. However, IMHO I feel that the fine details are learned by experience (ie after your first kite). Bridles are black magic and are made only by the high priests of a secret society where they make kites all the time and spend every spare moment flying (or not flying) their newest creations--secret handshakes, oaths, etc are administered after many long years of hard labor and the new 'bridlemaker' is sent forth into the world (or InterNet) to flame everyone asking 'newbie' questions. The preceeding paragraph is a joke (I hope). My point is--to quote a kiting friend of mine-- "Hey, it's only a kite". Take it easy, enjoy the experience and if it doesn't fly then try to do better next time. We're all adults in a child's world of toys and I think that many of us lose sight of the fact that this is a hobby--something to be savored. If you're not having fun... ...why the heck are you doing it? Adrian = = = = = = = = = = = = = = = = = = = = = = = = = = = = = = = = = = = = = = = Date: Fri, 20 Jan 1995 21:28:14 -1000 From: andrew@tug.com (Andrew Beattie) Message-Id: Organization: /usr/lib/news/organisation Subject: Re: Kite making newbie asks stupid questions Here's my answers to Peter's questions, I encourage others to put their views. peterk@wfw.wtb.tue.nl (Peter Kruijt) writes: >1. Are plans in general with or without seams? Good question. There is no standard. Some people mark the sewing-line and cut a seam alowance round it. This gives you a line to follow as you sew. My preference is to have a template the size of the fabric that I can quickly hot-cut round, and sew with a consistant seam allowance. The straight line that I follow is the edge of the fabric against the side of the foot rather than a pencil-line against the needle. >2. This kite has dacron on the `bottom' (sorry for this, but I don't know what > to call it correctly in english). Doesn't this make that the kite becomes > noisier and less stable? I would expect a Dacron trailing edge to make the kite quieter by damping vibration. >3. How important is symmetry? There is not hard and fast rule that says that kites should be symetric. Feel free to explore strange shapes. >4. How important is the weft? Alignment with the weft is important as the fabric will stretch. I don't differentiate between warp and weft when building. >5. Are there other important things one has to regard when making a kite? The > bridle is, but are there some things one easily forgets or disregards? Hmmm... Use big stitches to minimise the number of holes in the fabric Remember that the fabric has a front and a back Think *before* sewing. Andrew -- Read the Kite FAQ's: ftp.hawaii.edu:/pub/rec/kites/faq o /\ Kite Jumping: For sale: Prototype Keelless Rowlands Flowform. 2.3m^2 |_ \/ If you want 2.3m^2, Spectra Bridle, Flo-Yellow Carrington Fabric, US$80 (_\ to fly, use a >>Kite Fliers Site: http://www.kfs.org/kites<< andrew@tug.com Hangglider = = = = = = = = = = = = = = = = = = = = = = = = = = = = = = = = = = = = = = = Date: Sun, 22 Jan 1995 19:14:36 -1000 From: jburka@Glue.umd.edu (Jeffrey C. Burka) Message-Id: <3fvdvs$6m6@geog20.umd.edu> Organization: Project Glue, University of Maryland, College Park Subject: Re: Kite making newbie asks stupid questions In article , Andrew Beattie wrote: >Here's my answers to Peter's questions, I encourage others to put their views. >>1. Are plans in general with or without seams? >Good question. There is no standard. Some people mark the sewing-line and >cut a seam alowance round it. This gives you a line to follow as you sew. > >My preference is to have a template the size of the fabric that I can quickly >hot-cut round, and sew with a consistant seam allowance. The straight line >that I follow is the edge of the fabric against the side of the foot rather >than a pencil-line against the needle. Here's a partial agreement. I, too, use the edge of my presser foot as an alignment tool (and as a result, I use a 3/8" seam allowance). However, I like to make my templates to completed size, so they don't include a seam allowance. a) I've found that there are situations where it's useful to be able to see the sewing line on both pieces of fabric in order to line up panels b) I almost never press my hems (and especially never if it's a curved trailing edge); I roll them as they approach the presser foot. By having the finished edge marked with a line on the "right side" (ie against the face of the sewing machine), I know exactly how much to roll the edge. c) My "cutting table" is actually a pinball machine (one becomes quickly accustomed to working on a slant... ;-) and it's not big enough for many of the templates I use. For straight edges, I have a piece of heavy posterboard about two feet long which I use to do edges as series of segments. Because the curved pieces have the actually sewing/finished line marked, I don't worry about free-handing the cut. (applique pieces are another matter, and I virtually always hot cut around the template) d) For some reason, people are always asking to borrow my templates, and I prefer to let folks use whatever seam allowance they want Sure, there's some extra work in adding the extra cutting line once I've traced a template, but overall I've found my methods to suit me, and that's all I care about. >>3. How important is symmetry? >There is not hard and fast rule that says that kites should be symetric. >Feel free to explore strange shapes. Perhaps, but with respect to a kite that has *intended* symmetry, such as a delta, the symmetry is fairly important, though not vital, particularly in early attempts. For instance, a dual line kite with some asymmetry will still fly, and with minor inconsistenices, one might subconsciously make adjustments to the unequal ways in which the kite turns and not even realize that it's off. With a single line kite with a bridle attached along the central vertical axis, like an eddy or keeled delta, symmetry is pretty important. Kites with multiple bridles across the horizontal surface of the kite (flares, parafoils, roks, etc.) are much easier to adjust when the kite wants to fly to one side or the other. >Think *before* sewing. Yeah. What he said. Jeff -- |Jeffrey C. Burka | Pithy, insightful quote to be inserted | | | when one occurs to me. *If* one occurs | |jeffy@glue.umd.edu | to me. | = = = = = = = = = = = = = = = = = = = = = = = = = = = = = = = = = = = = = = = Date: Mon, 23 Jan 1995 01:39:47 -1000 From: travell@comics.enet.dec.com (I want to Go Fly a Kite!) Message-Id: <9501231139.AA28106@vbormc.vbo.dec.com> Organization: Harvard University Office of Information Technology Subject: Re: Kite making newbie asks stupid questions Andrew Beattie writes: >Remember that the fabric has a front and a back How do you tell which is which, Does it matter, except for colour or surface finish matching ?? John Travell. Solent Kite Flyers is a NEW Kite club based around Southampton, UK, Contact me by Email "travell@comics.enet.dec.com" for further info. = = = = = = = = = = = = = = = = = = = = = = = = = = = = = = = = = = = = = = = Date: Mon, 23 Jan 1995 01:33:18 -1000 From: plepez@ulb.ac.be (Philippe Lepez) Message-Id: <3g045u$dfd@rc1.vub.ac.be> Organization: Free University of Brussels Subject: Re: Kite making newbie asks stupid questions In article , andrew@tug.com (Andrew Beattie) says: > >>4. How important is the weft? >Alignment with the weft is important as the fabric will stretch. I don't >differentiate between warp and weft when building. I used to no differentiate. And one day I got the specs of a particular fabric. The warp was much stiffer (sorry if this is an inapropriate word). The weft beeing approximately equal to 45 degree. Good winds. Philippe. -- Philippe Lepez (CP 125), | | Good kite Universite Libre de Bruxelles, | Email: plepez@ulb.ac.be |+ Good wind 50 av. Roosevelt, | Phone: 32.2.6503553 |---------------- 1050 Bruxelles, Belgique. | Fax : 32.2.6503323 |= A lot of fun ! = = = = = = = = = = = = = = = = = = = = = = = = = = = = = = = = = = = = = = = Date: Mon, 23 Jan 1995 02:16:33 -1000 From: vogehe@etinovell.etec.uni-karlsruhe.de (Heinrich Vogelmann) Message-Id: Organization: Elektrotechnisches Institut Uni Karlsruhe Subject: Re: Kite making newbie asks stupid questions In article andrew@tug.com (Andrew Beattie) writes: ... >Here's my answers to Peter's questions, I encourage others to put their views. >peterk@wfw.wtb.tue.nl (Peter Kruijt) writes: >>1. Are plans in general with or without seams? >Good question. There is no standard. Some people mark the sewing-line and >cut a seam alowance round it. This gives you a line to follow as you sew. ... Ok, but how is it in the quoted book: Neue Lenkdrachen und Einleiner (New Stunt Kites and Single Liners) Text in German, Falken Verlag, price 24.80 DM, ISBN 3-8068-1353-1 80 pages ? In this book is no hint to the seam of the given measurements. Can someone clearing up this question definitely ? Axel, Bernhard ... ? ---------------------------------------------------- Heinrich Vogelmann Elektrotechnisches Institut Universitaet Karlsruhe 76128 Karlsruhe tel.: 049 0721 608 2700 fax: 049 0721 338854 e-mail: vogehe@etinovell.etec.uni-karlsruhe.de ---------------------------------------------------- = = = = = = = = = = = = = = = = = = = = = = = = = = = = = = = = = = = = = = = Date: Mon, 23 Jan 1995 09:36:30 -1000 From: andrew@tug.com (Andrew Beattie) Message-Id: Organization: /usr/lib/news/organisation Subject: Re: Kite making newbie asks stupid questions travell@comics.enet.dec.com (I want to Go Fly a Kite!) writes: >Andrew Beattie writes: > >>Remember that the fabric has a front and a back > >How do you tell which is which, Does it matter, except for colour or >surface finish matching ?? The front looks better and will look better longer. The difference is immediately obvious to any competent kite builder. I find it very difficult to tell which side is which, so I use one of two methods: 1) On the fabric that I use, the front is on the outside of the roll. 2) I make a mark with a fine felt-tip pen at the edge of the fabric (where it will be hidden in the hem). If you mark the front you get a small, well-defined spot. If you mark the back, the ink will spread between the fibres to make a much larger mark. You owe the Kite Oracle Zaphod Beeblebrox's other head on a platter. Andrew -- Read the Kite FAQ's: ftp.hawaii.edu:/pub/rec/kites/faq o /\ Kite Jumping: For sale: Prototype Keelless Rowlands Flowform. 2.3m^2 |_ \/ If you want 2.3m^2, Spectra Bridle, Flo-Yellow Carrington Fabric, US$80 (_\ to fly, use a >>Kite Fliers Site: http://www.kfs.org/kites<< andrew@tug.com Hangglider = = = = = = = = = = = = = = = = = = = = = = = = = = = = = = = = = = = = = = = Date: Mon, 23 Jan 1995 10:43:04 -1000 From: rolf@login.dknet.dk (Rolf V. Oestergaard) Message-Id: Organization: DKnet / EUnet Denmark - Login Tjenesten Subject: Re: Kite making newbie asks stupid questions Alice Hayden and others wrote: >Fabric on cross grain (diagonally) stretches. This could affect flight if >the sail stretches where you don't want it to. Is this really _that_ important? If so, how do You calculate the direction(s) where the stress over the kites lifetime will be maximum? I know everybody says it's important, and I know that many kites have the grain parallel to some part of their (curved) leading edge, but is that the whole story? How about the force from the bottom of the spine (no bungee!) 45 degree up in the sail on both sides? See You on FAN0, ______________ Rolf V. Oestergaard, Copenhagen, Denmark \ /\ / email: rolf@login.dknet.dk \/ \/ = = = = = = = = = = = = = = = = = = = = = = = = = = = = = = = = = = = = = = = Date: Tue, 24 Jan 1995 16:47:48 -1000 From: mgraves@leadingedg.win.net (Michael Graves) Message-Id: <1587@leadingedg.win.net> Subject: Re: Kite making newbie asks stupid questions >>4. How important is the weft? While others have addressed your other questions in good detail, this thing about weft deserves a bit more attention. My own experience with bias placement is that warp is very stable, bias is very UNstable, and weft somehwere in between. This is because the cloth is held in constant tension along its length as it is woven, but the shuttles stop and start each pass of the loom. In some brands of cloth the weft is almost as unstable as the bias, though I cannot recall off hand which ones I experimented with. Ultimately dimesional stability is something that has to be considered in the context of the kite design. I like Carrington K-42 because it reacts to wind pressue in a very organic manner, so my stunt kites are designed to take advantage of this fact. That is, the leading edge is placed on the bias, and trailing edge on the warp. Several people have told me they hate K-42 because its too "spongy". Ripstop polyesters are almost another matter competely, since they are VERY stable in general. This means that you the kitemaker have to plan any camber desired. That implies designin three dimesions instead of two, which can be a lot more difficult. My feeling is that ripstop polyester generally demands more of the kitemaker. Michael Graves ...who has spent the past 6 months getting to know Icarex by adapting an indoor variation of a previous design that used K-42. = = = = = = = = = = = = = = = = = = = = = = = = = = = = = = = = = = = = = = =