---------------------------------------------------------- Zenith640-List Digest Archive --- Total Messages Posted Tue 01/06/09: 7 ---------------------------------------------------------- Today's Message Index: ---------------------- 1. 08:11 AM - leading edge bends? (pilot4pay) 2. 09:40 AM - Re: leading edge bends? (Carlos Sa) 3. 12:33 PM - Re: leading edge bends? (Christian Tremblay) 4. 01:02 PM - Re: leading edge bends? (Keith Ashcraft) 5. 01:47 PM - Re: leading edge bends? (Carlos Sa) 6. 06:40 PM - Re: leading edge bends? (Ron Lendon) 7. 07:15 PM - Re: leading edge bends? (ZodieRocket) ________________________________ Message 1 _____________________________________ Time: 08:11:19 AM PST US Subject: Zenith640-List: leading edge bends? From: "pilot4pay" Chris, being that you are a scratch builder, I would like your advice on leading edge bending. How did you achieve the proper radius? did you use a cylinder of the same diameter as the radius design spec? Just asking, as I will need to make an appropriate leading edge bend in my tank skins. Any others wishing to offer intuition on the topic is welcome. Thanks! -------- Craig Smith CH640 builder SN: 0078 "Just think how stupid the average person is, and then realize that half of them are even stupider!" --George Carlin Read this topic online here: http://forums.matronics.com/viewtopic.php?p=223133#223133 ________________________________ Message 2 _____________________________________ Time: 09:40:02 AM PST US From: "Carlos Sa" Subject: Re: Zenith640-List: leading edge bends? Craig, I am building a 601HD, but the process still applies. I have used a 2 3/8" OD PVC pipe. The radius on the HD wing is 53 mm. I attached the pipe to a 2x6 to make sure it would not flex, and used those cargo straps to start the bend. After things were in place, I used a 8'x1'x5/8" board (from the hw store, to make shelves) to "squeeze" it. I'll email a picture off-list, as it is > 1 MB. Another method involves bagging the skin and applying vacuum from a vacuum cleaner. I've seen a video, and it is amazing ! Unfortunately it has been removed from youtube, but you can find postings on the subject on the zenithlist: search for Leading Edge Skin Vacuum Forming. Good luck Carlos CH601-HD, plans 2009/1/6 pilot4pay > pilot4profit@sbcglobal.net> > > Chris, being that you are a scratch builder, I would like your advice on > leading edge bending. How did you achieve the proper radius? did you use a > cylinder of the same diameter as the radius design spec? > Just asking, as I will need to make an appropriate leading edge bend in my > tank skins. > Any others wishing to offer intuition on the topic is welcome. > Thanks! > > -------- > Craig Smith > CH640 builder > SN: 0078 ________________________________ Message 3 _____________________________________ Time: 12:33:31 PM PST US Subject: Zenith640-List: Re: leading edge bends? From: "Christian Tremblay" I Craig and Carlos, Happy New Year 2009 [Laughing] I am not an expert, but what I did and understand on that matter : 1 - From Document Standard Spec of Chris Hans for CH640, CH specifyed to bend with a radius of 3mm for bending 6061-T6 in 0.016, 0.025, 0.032 and 0.040 thickness and a radius of 6mm for bending 0.050 and 0.063 thickness. 2 - The radius is half of a circle diameter. 3- To bend 0.025 or 0.023 of your tank you shoud acheive this with a 3mm radius. 4 - More thick are the alum sheet, more radius you should have. If radius is to small, "microcrak" are too numerous. Il radius is too high, it could made bends less loose or weak. 5- A rod of 1/8 inch in diameter have a diameter of +- 5-6mm (You can buy those rod in a Home Hardware Store). If you wrap a 0.025 alum sheet around this rod, you will obtain +- 3mm radius. This will be pretty close for 0.025 and 0.032, a little bit loose for 0.016, a bit stiff for 0.040. But all will be in the tolerance values calculated by in the CH. For my alu brake, I welded to rod, 1/8 and 1/2 on both side of a plate (see my web site : section Tool). www.zodiac640.com See you Chris -------- Christian Tremblay - Montreal, Qc A guy who build a CH640 from plan - SN0059 www.zodiac640.com Read this topic online here: http://forums.matronics.com/viewtopic.php?p=223191#223191 ________________________________ Message 4 _____________________________________ Time: 01:02:01 PM PST US From: Keith Ashcraft Subject: Re: Zenith640-List: leading edge bends? All, I have the MOV file on my computer, but... it is 705MB. It was from the Sonex guys, so maybe check the Sonex web site and see if they have the video. Keith CH701 -- scratch N 38.9940 W 105.1305 Alt. 9,100' ***************************************************** ________________________________ From: Carlos Sa Sent: Tuesday, January 6, 2009 10:39:50 AM Subject: Re: Zenith640-List: leading edge bends? Craig, I am building a 601HD, but the process still applies. I have used a 2 3/8" OD PVC pipe. The radius on the HD wing is 53 mm. I attached the pipe to a 2x6 to make sure it would not flex, and used those cargo straps to start the bend. After things were in place, I used a 8'x1'x5/8" board (from the hw store, to make shelves) to "squeeze" it. I'll email a picture off-list, as it is > 1 MB. Another method involves bagging the skin and applying vacuum from a vacuum cleaner. I've seen a video, and it is amazing ! Unfortunately it has been removed from youtube, but you can find postings on the subject on the zenithlist: search for Leading Edge Skin Vacuum Forming. Good luck Carlos CH601-HD, plans 2009/1/6 pilot4pay Chris, being that you are a scratch builder, I would like your advice on leading edge bending. How did you achieve the proper radius? did you use a cylinder of the same diameter as the radius design spec? Just asking, as I will need to make an appropriate leading edge bend in my tank skins. Any others wishing to offer intuition on the topic is welcome. Thanks! -------- Craig Smith CH640 builder SN: 0078 ________________________________ Message 5 _____________________________________ Time: 01:47:50 PM PST US From: "Carlos Sa" Subject: Re: Zenith640-List: leading edge bends? One more thing I forgot to mention: the tank can follow the curvature of the wing nose skin - but you can also simplify and make it straight, like the XL tanks... See bottom half of this page: http://www.zenithair.com/zodiac/xl/design-wings.html Carlos ________________________________ Message 6 _____________________________________ Time: 06:40:42 PM PST US Subject: Zenith640-List: Re: leading edge bends? From: "Ron Lendon" pilot4pay wrote: > Chris, being that you are a scratch builder, I would like your advice on leading edge bending. How did you achieve the proper radius? did you use a cylinder of the same diameter as the radius design spec? > Just asking, as I will need to make an appropriate leading edge bend in my tank skins. > Any others wishing to offer intuition on the topic is welcome. > Thanks! I'm not Chris but you can see the process I used to bend my leading edge skins Go to mykitlog site, click on the Wings link and search for "Cut and bend LE Skin". I have eight entries there showing the process I used. The 58mm stop block is right for the XL leading edge radius. Just some food for thought, -------- Ron Lendon, Clinton Township, MI WW Corvair with Roy's Garage 5th bearing Zodiac XL, ScrapBuilder ;-) http://www.mykitlog.com/rlendon Read this topic online here: http://forums.matronics.com/viewtopic.php?p=223261#223261 ________________________________ Message 7 _____________________________________ Time: 07:15:59 PM PST US From: "ZodieRocket" Subject: Zenith640-List: Re: leading edge bends? http://www.ch601.org/resources/Nose%20Skin/bending_a_nose_skin.htm Pictures tell the whole story Mark Townsend Alma, Ontario Zodiac CH650 C-GOXL, CH701 Rotax 912, STOL CH750 Just started www.ch601.org / www.ch701.com / www.Osprey2.com ------------------------------------------------------------------------------------- Other Matronics Email List Services ------------------------------------------------------------------------------------- Post A New Message zenith640-list@matronics.com UN/SUBSCRIBE http://www.matronics.com/subscription List FAQ http://www.matronics.com/FAQ/Zenith640-List.htm Web Forum Interface To Lists http://forums.matronics.com Matronics List Wiki http://wiki.matronics.com Full Archive Search Engine http://www.matronics.com/search 7-Day List Browse http://www.matronics.com/browse/zenith640-list Browse Digests http://www.matronics.com/digest/zenith640-list Browse Other Lists http://www.matronics.com/browse Live Online Chat! http://www.matronics.com/chat Archive Downloading http://www.matronics.com/archives Photo Share http://www.matronics.com/photoshare Other Email Lists http://www.matronics.com/emaillists Contributions http://www.matronics.com/contribution ------------------------------------------------------------------------------------- These Email List Services are sponsored solely by Matronics and through the generous Contributions of its members.