From: rloiseau@aol.com (RLoiseau) Subject: Carbon fighter spines. Date: Fri, 21 Jun 1996 12:28:30 -1000 Organization: America Online, Inc. (1-800-827-6364) Message-ID: <4qf7me$nki@newsbf02.news.aol.com> Does anyone have any experience with bowing carbon Fiber for fighter spines? I have heard that one can split the carbon, epoxy it, and let the epoxy dry in a mold. I have never tried it, it seems a bit hard though. I have also been told that carbon should be able to be bowed by heating it. It is held toghether with epoxy, so supposedly you can heat the epoxy to the right temparture, bend it, and let it cool. I tried it, but at a certain temparture the epoxy would fail, and there would be a "joint" in the carbon--just the fibers, and they could bend, but no epoxy holding them. Now I am thinking If I can find what kind of epoxy is used in the spars I can repar the joint, but leave a bend. Any suggestions? Later!! Robin Levick Transcendent Kites RLoiseau@aol.com(the bird) Transcendent kites Robin Levick = = = = = = = = = = = = = = = = = = = = = = = = = = = = = = = = = = = = = = = From: johnsen@eskimo.com (Brian Johnsen) Subject: Re: Carbon fighter spines. Message-ID: Organization: Tethered Airfoil R&D Pty. Ltd.(C)(R)(TM) CD CASS Date: Sat, 22 Jun 1996 07:30:07 -1000 In article <4qf7me$nki@newsbf02.news.aol.com>, RLoiseau wrote: >Does anyone have any experience with bowing carbon Fiber for fighter >spines? >I have heard that one can split the carbon, epoxy it, and let the epoxy >dry in a mold. I have never tried it, it seems a bit hard though. I have >also been told that carbon should be able to be bowed by heating it. It >is held toghether with epoxy, so supposedly you can heat the epoxy to the >right temparture, bend it, and let it cool. I tried it, but at a certain >temparture the epoxy would fail, and there would be a "joint" in the Once epoxy has cured, there is no way to way to form it subseqently. It's a one way only deal. The thing that gives epoxy spars their strength is the bonding of the fibers to each one next to it so they don't slide. Heating a cured epoxy matrix too much breaks the chemical bonds that hold things together and they no longer go back where they came from when it cools. The only reliable way I've found yet to put a kink in CF is to cut it and epoxy a triangle to the inside angle. I tried the split & reglue once but it broke along the split on the first nosedive. You can get some nasty splinters in the process as well. -- Swiss Computer Scientists Produce Clairvoyant Humor Impaired Kitten -- Brian Johnsen johnsen@eskimo.com Seattle, Washington USA = = = = = = = = = = = = = = = = = = = = = = = = = = = = = = = = = = = = = = = From: sendan Subject: Re: Carbon fighter spines. Date: Sat, 22 Jun 1996 19:22:05 -1000 Organization: Hawaii OnLine - Honolulu, HI Message-ID: <31CCD47D.55D3@aloha.net> Brian Johnsen wrote: > The only reliable way I've found yet to put a kink in CF is to cut it > and epoxy a triangle to the inside angle. > > I tried the split & reglue once but it broke along the split on the > first nosedive. You can get some nasty splinters in the process as well. I have heard of people bending fibreglass rod by putting a thin brass ferrule over the area they want to bend and then bending. this gives a fibre-filled clean bend. It is supposed to work. Whether or not it would work with carbon.... btw, i was in india for most of the past year. And i _just happened_ ;-) to bring back two hundred paper and bamboo fighters. Not the absolute best quality, but not bad. this is more than i could ever use. and besides, the rice paste they glue with breaks down in two years anyway. I also have limited quanties of manja-glass coated line. this is top quality stuff. This just might be an offer to anyone Really Interested. have fun. nathansendan = = = = = = = = = = = = = = = = = = = = = = = = = = = = = = = = = = = = = = = From: birdofplay@aol.com (BirdofPlay) Subject: Re: Carbon fighter spines. Date: Sat, 22 Jun 1996 17:42:00 -1000 Organization: America Online, Inc. (1-800-827-6364) Message-ID: <4qiee8$2e3@newsbf02.news.aol.com> Epox is OLD tech glue - it's the 90s try... Superglue... doesn't it work on everything ? You can even glue your wife to the work bench if you have a mind or an accident. Seeing the panic in her eyes was almost worth the accompaning grief. ... "If I just hadn't laughed" ;-( Ok, here's what I've done ... First I tried splitting the CF rods in half with an Xacto knife. The rods/spines were still a bit tough, so next I tried to split 'em twice, leaving three splinters. CF rod is made with CF strands and as such splits pretty easily and uniformly. ( use SHARP knife - be careful ) I split it back to , just short of, the upper line attach point ( if a two line bridle ie. Indian fighter ) then ... bend the rod to the desired shape and hit it with thin superglue. If you want you could put a piece of wax paper on top of a "pinable" surface ( balsa plank ) and use some straight pins to actually hold the CF rod splinters in "tight formation" all along the bend. The stuff tends to "kinda" seperate and go it's own way. The "thin" super glue should penetrate the split gaps via "capillary" action. If you are in a hurry and feel like treating yourself to the luxury of instant gratification then get some of the super glue "quick set" spray. It has a nice aromatic aroma. ( amines ) If you are truely a KLUTZ - be sure to wear surgical gloves and old clothes - lest you suffer the fate of my wife. See above. All the super glue stuff should be available at your local model aircraft supplier / hobby shop. Hey, if you wanna be able to skim launch you're fighter you gotta have a bow in the spine, right ? Or high grass/weeds ! I've flown mine without any bow in the CF and, with practice and luck, they can be flown "pretty OK" . IMHO It's pretty unstable, but, I hear, some guys like that ! Disclaimer deluxe : I'm not a Fighter jock with lots O experience. Just an old time model AC buider with ideas. I'm really looking forward to the BIG Fighter thang at WSKIF this Aug. ( Right Gina ? ) I fly for fun and have not been in any "sky duals" . Noone else in my area even considers fighters. Let me know how you make out with these techniques. Fighters are so cheap and easy to build that you can experiment your butt off and still not spend a fortune in cash or time. I think that guys are missing out on lots of fun when they dismiss fighters. Best regards -- Bob Neitzke birdofplay@aol.com http://members.aol.com/birdofplay = = = = = = = = = = = = = = = = = = = = = = = = = = = = = = = = = = = = = = = From: Marty Sasaki Subject: Re: Carbon fighter spines. Date: Mon, 24 Jun 1996 06:22:29 -1000 Organization: Division of Applied Sciences, Harvard University Message-ID: <199606241622.MAA17665@endor.harvard.edu> My suggestion is to not bother with carbon fiber spines. Just use bamboo. It is easily formed and shaped. It is inexpensive. If you blow a spine, you can use it to skewer meat and vegetables for the grill. The shape of a spine isn't that critical, so usable spines are easy to make. -- Marty Sasaki sasaki@das.harvard.edu = = = = = = = = = = = = = = = = = = = = = = = = = = = = = = = = = = = = = = = From: pp@win.tue.nl (Peter Peters) Subject: Re: Carbon fighter spines. Date: Mon, 24 Jun 1996 02:33:49 -1000 Organization: Eindhoven University of Technology, The Netherlands Message-ID: <4qm1vd$aj1@svin09.win.tue.nl> <4qepi3$i6c@newsbf02.news.aol.com> <4qf7me$nki@newsbf02.news.aol.com> In article <4qf7me$nki@newsbf02.news.aol.com>, rloiseau@aol.com (RLoiseau) writes: >Does anyone have any experience with bowing carbon Fiber for fighter >spines? >I have heard that one can split the carbon, epoxy it, and let the epoxy Why would you want to split it ? There is 0.3 mm carbon these days..is that too thick ? Or does splitting have other advantages ? Peter -- Peter Peters, pp@win.tue.nl, http://www.win.tue.nl/~pp/ Like kites.... look at http://www.win.tue.nl/~pp/kites/ = = = = = = = = = = = = = = = = = = = = = = = = = = = = = = = = = = = = = = = From: kitestudio@aol.com (Kitestudio) Subject: Re: Carbon fighter spines. Date: Mon, 24 Jun 1996 03:53:05 -1000 Organization: America Online, Inc. (1-800-827-6364) Message-ID: <4qm6k1$avu@newsbf02.news.aol.com> I have a fighter in the store made by Ed Shenk of Lankaster, PA. He uses .07 graphite in the spine and bows it by spliting then holding to a form and re-gluing with a fresh CA. After glueing, the two uneven ends are trimmed. I asked him how he keeps the rod from becoming glued to the form... He said it is a little messy and takes a lot of practice. Ed has used this technique on several kites an says they will hold up to those nose dives. I hope to test his claim soon. However, I have little reason to doubt him - he make some wonderfull kites and pays a lot of attention to detail. = = = = = = = = = = = = = = = = = = = = = = = = = = = = = = = = = = = = = = = From: "John F. Holland" Subject: Re: Carbon fighter spines. Date: Mon, 24 Jun 1996 11:35:54 -1000 Organization: Sandia National Laboratories Message-ID: <4qn1nq$h73@news.sandia.gov> Here, Here !! I could not agree with you any more Marty! Bamoboo (sorry Bamboo) is probably the best material for fighter kite spines and bows (IMHO). It is a heck of lot easier to work with than trying to shape v carbon fiber. ---- John Holland Albuquereque, NM = = = = = = = = = = = = = = = = = = = = = = = = = = = = = = = = = = = = = = = From: pdjnjvt@knoware.nl (Peter de Jong) Subject: Re: Carbon fighter spines. Date: Tue, 25 Jun 1996 09:48:45 -1000 Organization: Knoware Internet Message-ID: <31d000bc.3235576@news.knoware.nl> On 24 Jun 1996 21:35:54 GMT, John F. Holland wrote: >Here, Here !! > >I could not agree with you any more Marty! Bamoboo (sorry Bamboo) is probably >the best material for fighter kite spines and bows (IMHO). It is a heck of lot >easier to work with than trying to shape v carbon fiber. > >---- A possible source of suitable bamboo: Look for those rollup/rolldown window shades in an oriental store: made of thin bamboo sticks. Awfull lot of sticks in one roll.... Hope it helps... Regards, Peter Greetings from Holland Peter de Jong A&F Custom Kites Werkhoven NL = = = = = = = = = = = = = = = = = = = = = = = = = = = = = = = = = = = = = = =