Date: Tue, 14 Feb 1995 16:55:20 +1100 (EST) From: Allan Aaron Subject: Re: Mailing List Members/personal progress You've probably had a heap of advice regarding the dry spots in the lay ups. I'll add my 2 cents worth. I found that locally heating the layup works really well in getting an even distribution of epoxy. This seems even more important when you are peel plying since the peel ply has a different absorption rate than the glass. I use a hair drier (so whats new!). I also find the problem is much greater at lower temperatures. I'm currently completing my cannard (having skipped ahead a bit and done some more things in the nose and fuselage. One tip when you put the peel ply tape on the trailing edge of the canard is to only overlap as much as is needed to get a good bond between the top and bottom skins. I didn't think about it till too late and took off some of the foam at the trailing edge which I then had to fill with pour foam and micro. Finally, as far as personal skills are concerned I guess it depends on who you ask :-). My qaulifications are as an aeronautical engineer but I haven't worked as one for about ten years. I do see a lot of technology though through my job with a technology based venture capital investor. One piece of useful technology which I 'll follow up on later was developed by the national reseach body in Australia (CSIRO) and used by an acquaintance there who built a defiant. It is a UV protective undercoat that he used and swears by. If anyone is interested I'll get further details sooner rather than later. Allan Aaron | InterConnect Australia Pty. Ltd. Sydney, Australia | Australia wide Internet Access. | Telnet FTP Talk Email News and more. allana@interconnect.com.au | Voice: 03 528 2239 Email:info@interconnect.com.au Date: Fri, 17 Mar 1995 15:00:22 +1000 From: allana@interconnect.com.au (allana@interconnect.com.au) Subject: Canard/Elevator Fit Any advice about how to get an even gap between the trailing edge of the canard and the elevators. My surfaces all seem pretty straight however there are minor irregularities that mean that once mounted, the gap wont be consistent along the length of the surface. I had thought about covering the elevators with duct tape and filling the recess in the canard with micro and then squeezing the elevator into it. Any thoughts. A second question - probably done to death, is what is the preferred approach to filling the surfaces and getting the right contour before finishing. I've used a micro/safetyPoxy mix but I'm a bit concerned about the weight. I have had to add a fair bit to get the airfoil section to match the template precisely. Is there any alternative (better preparation I guess). Thanks in advance for any input. Date: Fri, 17 Mar 95 17:33:08 EST Subject: Canard/Elevator Fit (fwd) Allan Aaron asks: >Any advice about how to get an even gap between the trailing edge of the >canard and the elevators. My surfaces all seem pretty straight however >there are minor irregularities that mean that once mounted, the gap wont be >consistent along the length of the surface. I had thought about covering >the elevators with duct tape and filling the recess in the canard with micro >and then squeezing the elevator into it. Any thoughts. How much of a space do you have? If the maximum space you've got is smaller than the maximum allowable, I wouldn't put any more material on it (for weight reasons) - when you fill and paint the elevator and canard, the gap will get a reasonable amount smaller. I was very surprised how small the gap got when I painted my Q2. You might consider using a long sanding block on both the elevator trailing edge and canard (like 3 feet or so) to make them both dead straight with a reasonable gap. Conversely, if they both wiggle too much to sand enough off (even with a dry micro fill) to get them perfectly straight and matching, you could use a thin sanding stick (like a tongue depressor with 100 grit on it) to sand the canard trailing edge to a constant distance from the mounted elevator. Does any of this make any sense? >A second question - probably done to death, is what is the preferred >approach to filling the surfaces and getting the right contour before >finishing. I've used a micro/safetyPoxy mix but I'm a bit concerned about >the weight. I have had to add a fair bit to get the airfoil section to >match the template precisely. Is there any alternative (better preparation I >guess). There's been a lot of discussion of this lately on r.a.h (instigated by Sid, I think). Check it out. Using a dry micro mix is probably lighter than anything else you'll find out there - bondo and featherfill are pretty heavy, as are the straight epoxy or polyurethane primers. I'd guess it's best for 99% of the volume fill, and then use the other stuff for the surface finish. Be EXTREMELY careful hot-wiring the cores - that's where you'll get your shape accuracy. Any divots or bumps there will add a ton of fill later. Sand the cores to the template shape carefully if you've got bumps. -- Marc J. Zeitlin E-Mail: marcz@an.hp.com Date: Sun, 11 Jun 95 16:27:18 EDT Subject: Canard Shear Web Jigging People; In setting up the canard cores for glassing the shear web, the instructions say to use 8' 2x4's to support the cores. Turns out you need something like 11' 2x4's (or at least I do). Even with the shorter canard (let's not start THAT again!) the overall length of the three cores with shear web is 125" (10' 5"). Not a big deal if you happen to have more 2x4's lying around - just a head's up. Also, I'm probably going to be loaning my canard core hot-wire templates to Marty K. If anyone else is interested in using them after he's done (assuming he thinks they're usable and recommends them) you're welcome to - I just want them back eventually. They're made of 1/16" aluminum, and have the paper templates glued to one side. -- Marc J. Zeitlin E-Mail: marcz@an.hp.com From: Marc J. Zeitlin Subject: Canard Spar Caps Date: Tue, 20 Jun 95 13:13:14 EDT People; I glassed the bottom spar cap of the canard last night. It was very different, using the 3" tape and pulling out the cross threads, than using the UNI or BID. I was amazed how much glass you can pack into a given space. I do have a question for those of you who have glassed your canard already: How many layers of spar cap tape did you use? My layup looked like this; 1 -------------------- 2 -------------------------- 3 --------------------------------- 4 ---------------------------------------- 5 ---------------------------------------------- 6 ---------------------------------------------------- 7 --------------------------------------------------------- 8 --------------------------------------------------------------- 9 --------------------------------------------------------------------- and it filled (or even slightly overfilled) the trough, but I'm not completely comfortable with the notion that I should just fill the trough to the top, and not worry about the # of layers I use. I realize that Nat is tring to get a dimension and shape correct here, but if I use one layer too little, that's 11% of my bending strength! I have a lot more confidence in my ability to count the # of tape layers than in my ability to hot-wire to an EXACT dimension. So, is 9 layers a reasonable #? if some people say 8 and some say 10, I won't be too worried, but if a bunch of people say 12, I will. -- Marc J. Zeitlin E-Mail: marcz@an.hp.com Date: Tue, 20 Jun 1995 20:19:28 -0700 (PDT) From: Eric Westland Subject: Re: Canard Spar Caps Marc, My spar caps did not take the number of plies as shown in the plans as well. At first I suspected the cores were not cut out accurately, then I suspected a thicker shear web. I even did a test layup with the 3" tape and measured the thickness. I tried everything, double checked it all and finally settled on putting in what fit. I did stick with the schedule on both the canard and wings, but usually found the last couple of "short" layers were high. I was usually fine with the outer third of the span where there were 4 or 5 layers. I called Nat with the same concerns and he assured me there was enough glass there to be safe, but was not sure why all of the layers would not fit. After cure, I then sanded out the high spots so as not to change the airfoils. Not particularly pleasant work, but I knew I had in as much glass as possible and did not end up with a "bump" 25 to 50 thousandths high. I know what you're feeling, Marc. Despite the assurances from others that "it's ok", I would like a way to non-destructively test these parts before seat-belting myself inside of them. Any ideas? Eric p.s. Anyone coming to Arlington? Date: Wed, 21 Jun 1995 12:08:19 -0400 From: CozyBldr@aol.com Subject: Re: Canard Spar Caps In a message dated 95-06-20 13:15:57 EDT, Marc writes: >I glassed the bottom spar cap of the canard last night. It was very >different, using the 3" tape and pulling out the cross threads, than >using the UNI or BID. I was amazed how much glass you can pack into >a given space. I do have a question for those of you who have glassed >your canard already: > >How many layers of spar cap tape did you use? I went back and checked my log. My bottom spar cap came to 7 layers and my top was 10. I also ended up sanding it down a bit before skinning. I think you'll be fine with 9. Paul Stowitts Date: Thu, 22 Jun 1995 14:16:29 -0400 (EDT) From: Tech Support - Rick Subject: Re: Canard Spar Caps I seem to remember that in the Long Ez plans and newsletters that overfilling was a bad thing. The number of layers for the GU canard was minimally six I think, I'll double check this . Rick Date: Fri, 23 Jun 1995 08:00:13 -0400 From: MKansky@aol.com Subject: Uni tape for canard I just got the foam and uni-tape for the canard. What I received from wicks was looks like spar roving. Is this the right cloth? It doesn't look at all like the uni-cloth I have been using on the fuselage. I am calling Wicks today. I ordered foam, uni-tape, and about 8 machine screws. The total was 119.15. They then added 20.43 for shipping and a misc charge of $12. $32 for a $120 order seems very high! This was all in preparation for building the canard. ...Marty Date: Fri, 23 Jun 95 9:40:44 EDT Subject: Uni tape for canard (fwd) Marty K. writes; >I just got the foam and uni-tape for the canard. What I received from wicks >was looks like spar roving. Is this the right cloth? It doesn't look at all >like the uni-cloth I have been using on the fuselage. Yep - that's the right stuff. It should look like small bundles of fibers with a VERY loose thread running back and forth holding it together, and one plastic thread on one edge. That's the one you pull out, and then carefully pull all the cross-threads out. It comes out fairly easily, but you have to be careful and hold down the rovings when you do it. After you wet it out and squeegee it down, it packs INCREDIBLY tightly, since there are no cross threads at all. >I am calling Wicks today. I ordered foam, uni-tape, and about 8 machine >screws. The total was 119.15. They then added 20.43 for shipping and a misc >charge of $12. $32 for a $120 order seems very high! Does seem high. Foam is big, but not very heavy. -- Marc J. Zeitlin E-Mail: marcz@an.hp.com Date: Sat, 24 Jun 1995 23:05:03 -0700 (PDT) From: Eric Westland Subject: Re: Uni tape for canard On Fri, 23 Jun 1995 MKansky@aol.com wrote: > I just got the foam and uni-tape for the canard. What I received from wicks > was looks like spar roving. Is this the right cloth? It doesn't look at all > like the uni-cloth I have been using on the fuselage. > > I am calling Wicks today. I ordered foam, uni-tape, and about 8 machine > screws. The total was 119.15. They then added 20.43 for shipping and a misc > charge of $12. $32 for a $120 order seems very high! > > This was all in preparation for building the canard. > > ...Marty > I ordered some extra spar cap tape and ended up with about 8 pounds (however long that may be :-)) after I was all done with my canard and wings. If it looks like anyone may end up short, let me know and I will let it go for whatever it is worth. Shipping should be less than $32! Eric Date: Sun, 2 Jul 95 0:38:50 EDT Subject: Canard Antennae People; While lying on the beach, soaking up the rays (and trying to not hear my wife telling me about skin cancer :-) ) I was thinking about the bottom skin layup I had finished on Wednesday, before leaving on vacation. It struck me that I had COMPLETELY forgotten to install any antennae in the canard. After 2 minutes of panic, I thought; hey, if the antenna's in the bottom, the signal has to go through 3 layers of glass to get to it. If I put the antenna under the top skin (assuming I can still keep the skin VERY smooth) the signal will still have to go through the bottom 3 layers of glass, but will also have to go through 2 - 3 inches of foam. It's hard for me to imagine that this will make any difference at all, but before I do it, I figured I'd ask if any of you with some E.E. experience knew why this won't work. Thanks. (but mom, if I don't make mistakes, how will I LEARN?) :-). -- Marc J. Zeitlin E-Mail: marcz@an.hp.com Date: Thu, 6 Jul 1995 17:07:29 -0400 From: MKansky@aol.com Subject: Canard Templates Marc, your canard templates worked great. Thanks so much for letting me use them. Does anyone else want to borrow them? I plan to return them to Marc next week if I don't hear from anyone. It took me about four hours to cut the canard. A little more than the two hours stated in the plans. ....Marty From: Marc J. Zeitlin Subject: Canard Templates (fwd) Date: Thu, 6 Jul 95 17:40:04 EDT Marty K. writes; >Marc, your canard templates worked great. Thanks so much for letting me use >them. Great! Glad you liked them. >Does anyone else want to borrow them? I plan to return them to Marc next >week if I don't hear from anyone. > >It took me about four hours to cut the canard. A little more than the two >hours stated in the plans. Yeah, I think that's what it took me (and Deanie) too. One point to make here - I did the top spar layup last night, and put in 11 layers of glass. That, with the 9 layers in the bottom spar cap, took about 1.3 to 1.5 times as much tape as the plans called for. So, I make the assumption that my troughs were cut a little deep, as Marty's now are :-) and that I used more glass than Nat called for. Paul S. said he did 7 bottom and 10 top, Rick C. said he THOUGHT the L.E. plans said 6 minimum, and Eric W. didn't have an exact #, but seemed to indicate that the plans gave some indication of the # of layers and that he didn't hit it ?!? So, my interpretation (as a handwaving engineer) is that I've got more than anyone else, and more (as we all know :-) ) is better. No, no, wait, I mean that it'll be strong and stiff enough (I can't imagine that it would be TOO strong or stiff) but might weigh a pound or two extra. Better than the opposite, I guess. Just wanted to let anyone considering using these templates what they're in for. The frustrating thing is that the plans don't say how much glass to use, and Nat apparently wouldn't tell Eric W. when he asked. -- Marc J. Zeitlin E-Mail: marcz@an.hp.com Date: Thu, 6 Jul 1995 22:18:15 -0700 (PDT) From: Eric Westland Subject: Re: Canard Templates (fwd) > > Just wanted to let anyone considering using these templates what they're > in for. The frustrating thing is that the plans don't say how much > glass to use, and Nat apparently wouldn't tell Eric W. when he asked. > > -- No, not exactly. nat was helpful in trying to help me figure out how what I had 2000 miles away may have deviated from the plans, he just could not explain how the lay up schedule could have worked out different. Sorry if I was not clear. Eric Date: Fri, 7 Jul 1995 12:37:31 -0400 (EDT) From: Tech Support - Rick Subject: Re: Wing Templates I was looking in the Long - Ez plans and Cp's last night looking for the spar cap plies numberof minimum plies. Your answer to this question was to the inside of the line, not the outside. The number of plies for the canard in the Long plans is 11 plies of UND cloth. I'm still looking for the minimum plies needed. As far as gaps go, a 1/4" is supposedly allowable, bu no more than an 1/8" is really recommended. Rick On 6 Jul 1995, Judd Stewart wrote: > COZY Builders, > > 1) Do you trim to the OUTSIDE or INSIDE of the line. > > If my memory serves me I had to trim to the inside of the line of the elevator > (original Long EZ canard) otherwise they would be to heavy. All other surfaces > were to the line. > > Any Comments..... > > Judd > > Date: Mon, 10 Jul 1995 19:42:21 -0400 From: JIMWHI@aol.com Subject: Tips: Canard Layup Do not do the canard skin layups until after the spar caps have cured. Use your sanding block to bring the spar caps into contour before doing the outer skin layups. The plans give you option of doing it either way. The extra time spent doing it this way will pay off big when you do the finish contour later on, plus your canard airfoil shape will be right on. Jim White From: Marc J. Zeitlin Subject: Canard Spar Caps Date: Thu, 13 Jul 95 9:43:01 EDT I'm forwarding this for Nick P., who writes: (Sorry for the forwards, everyone, I had screwed up the alias list which forwards the mail around. Mea Culpa. Everything SHOULD be back to whatever passes for normal, now). >Canard Spar Cap slots. >====================== > >Assuming the following layup schedule is correct, there should be space for >more than 11 plies of uni tape in the slots of depth indicated on the >plans. If layup schedule is incorrect and there is interest, I will update >it and related thickness. > >Calculated thickness of web / spar cap using laminate analysis software. >(Cap is 11 plies of unidirectional tape). > > Ply Material Orientation ply thickness (in) > (degrees) dry wet out > ------------------ Web ----------------------- > 1 RA 7715 45 0.0095 0.011 > 2 RA 7715 -45 0.0095 0.011 > 3 RA 7715 45 0.0095 0.011 > 4 RA 7715 -45 0.0095 0.011 > 5 RA 7715 45 0.0095 0.011 > 6 RA 7715 -45 0.0095 0.011 > 7 RA 7725 45,-45 0.0125 0.016 > ----------------- Cap ------------------------ > 8 E-glas uni tape 0 0.025 0.039 > 9 E-glas uni tape 0 0.025 0.039 >10 E-glas uni tape 0 0.025 0.039 >11 E-glas uni tape 0 0.025 0.039 >12 E-glas uni tape 0 0.025 0.039 >13 E-glas uni tape 0 0.025 0.039 >14 E-glas uni tape 0 0.025 0.039 >15 E-glas uni tape 0 0.025 0.039 >16 E-glas uni tape 0 0.025 0.039 >17 E-glas uni tape 0 0.025 0.039 >18 E-glas uni tape 0 0.025 0.039 > ----- >Total thickness 0.502 (in) > > >Measured from the plans you will notice upper cap slot depth is 0.85 (in), >lower cap is 0.70 (in). Upper cap is in compression and lower cap is in >tension. Since ultimate tensile strength of E-glass is higher than >ultimate compressive strength of E-glass, lower cap can be thinner. > >There can be significant distortion in paper copies due to humidity etc., >for any real accuracy items requiring dimensional accuracy should be on >mylar film - especially the airfoil templates. From: Marc J. Zeitlin Subject: Canard Spar Caps (fwd) Date: Thu, 13 Jul 95 9:59:08 EDT So, Nick P. writes: >>Canard Spar Cap slots. >>====================== >> >>Assuming the following layup schedule is correct, there should be space for >>more than 11 plies of uni tape in the slots of depth indicated on the >>plans. If layup schedule is incorrect and there is interest, I will update >>it and related thickness. . . . >>Total thickness 0.502 (in) >>Measured from the plans you will notice upper cap slot depth is 0.85 (in), >>lower cap is 0.70 (in). Upper cap is in compression and lower cap is in >>tension. Since ultimate tensile strength of E-glass is higher than >>ultimate compressive strength of E-glass, lower cap can be thinner. Whoa!!! Marty K. (or maybe Lee D., by this point) has my canard templates so I can't measure them (guys?) but I don't think there's any way the trough for the shear web/spar caps was 0.85" or 0.70". My recollection was ~0.375" for the top, and ~0.25" for the bottom. I think it even says that in the plans (don't have them in front of me here at work). This would make your analysis layup too thick to fit, but my 11 ply layup did. I'm also not sure that the thickness of the spar cap tape would go from 0.025" to 0.039" per layer due to wetting out - given what seemed to happen during my layup, the thickness hardly increased at all with the addition of epoxy. There's some discrepancy here - I'm not sure exactly where. My guess is that my templates may have been a little deep, and the plies don't grow as much as calculated here. Just a guess. Oooh, wait, I just did a quick calculation; 0.85 cm (notice the "cm") works out to 0.335" (close to my recollection) and 0.70 cm works out to 0.276" (also close to my recollection). Nick, were you measuring in metric units? >>There can be significant distortion in paper copies due to humidity etc., >>for any real accuracy items requiring dimensional accuracy should be on >>mylar film - especially the airfoil templates. This is true, but the paper is all we've got. Also, the paper distortion (I studied paper distortion for a project here at work for a thermal recorder) tends to be omnidirectional, meaning that the paper may grow or shrink, but it shouldn't change shape with humidity. I would venture a guess that the variation in shape that will occur due to builder differences, hot-wiring differences, etc. would be much larger than the few percent differences in SIZE due to humidity effects. Good point, though. -- Marc J. Zeitlin E-Mail: marcz@an.hp.com Date: Mon, 17 Jul 1995 16:20:33 -0400 From: KSPREUER@aol.com Subject: Re: Canard Spar Caps I wrote a note a this a short time ago but would like to add some info from a test that Rutan did. I saw pictures of a test to failure on a canard. I don't remember the figures exactly, but I believe it was a total load of 1300 lbs worth of snd bags distributed on the canard. It was extremely impressive. I think the out come was that even at that load it did not break, but they couldn't stack the bags any higher. So while I put in the plans stack up in the spar caps, I certain a proof test will show good margin with fewer plies. Date: Mon, 17 Jul 95 16:31:11 EDT Subject: Re: Canard Spar Caps (fwd) Keith Spreuer wrote; >I wrote a note a this a short time ago but would like to add some info from a >test that Rutan did. I saw pictures of a test to failure on a canard. I don't >remember the figures exactly, but I believe it was a total load of 1300 lbs >worth of snd bags distributed on the canard. It was extremely impressive. I >think the out come was that even at that load it did not break, but they >couldn't stack the bags any higher. So while I put in the plans stack up in >the spar caps, I certain a proof test will show good margin with fewer plies. Hmmm. If it was 1300 lb., this isn't reassuring me. We (in the dim, dark past) calculated that the load on the canard could be ~23% of the gross weight. This works out to 0.23 x 2050 = 471.5 lbs. Normal category has a limit of 4.4 g's, which would work out to 2074.6 lbs. Usually, the designer will put a safety factor of anywhere from 10% to 50% on top of that, so I'd want to see 2282 lbs to 3111 lbs. 1300 lbs gives a load factor of 2.75 g's, with no safety factor. Now, it didn't break, but we don't know when it would have, either. If you said 2600 lbs., I'd be happy. -- Marc J. Zeitlin E-Mail: marcz@an.hp.com Date: Tue, 18 Jul 1995 01:15:33 -0400 From: KSPREUER@aol.com Subject: Re: Canard Spar Caps I went back and looked at the plans and of course you are not nuts. The plans do not give the number of plies. I did do some calculations to back into a number though. In the bill of materials (Ch 2) it specifies 42 yds of uni for chapter 10. I figured that it should be split in proportion to the thickness of the depth of the spar caps. I measured that off the template drawings as .341" for the top in the center and .256 for the bottom. That works out to 24 yds for the top and 18 yds for the bottom. In chapter 10 it also states that the proper distribution will probably take the cutting of each ply 4" shorter than the last. So starting at sta 19.5 and adding 4" to each ply you get out to sta. 62.5 in 6 plies and that adds up to 630" or 17.5 yds that is just right for the bottom. the top needs 6.5 more yds which equates to 2 more full length plies. So that would indicate that the plans standard is 6 plies on the bottom and 8 on the top. Like I said in the other e-mail the canard has a large margin of safety so this need not be considered a minimum. I feel a lot better knowing this though since I found large variation in the through depth. From: Marc J. Zeitlin Subject: Re: Canard Spar Caps (fwd) Date: Tue, 18 Jul 95 10:14:12 EDT Keith S. writes: (calculations deleted) . . >...... So that would indicate that the plans standard is 6 plies on >the bottom and 8 on the top. Like I said in the other e-mail the canard >has a large margin of safety so this need not be considered a minimum. >I feel a lot better knowing this though since I found large variation >in the through depth. This analysis makes the most sense of any so far - Thanks a bunch. Since I've got three extra plies top and bottom, I feel pretty secure. -- Marc J. Zeitlin E-Mail: marcz@an.hp.com Date: Wed, 19 Jul 1995 01:33:11 -0400 From: StetsonE@aol.com Subject: Spar Caps & EAA engines All this talk about canard spar caps caused me to check my Long-EZ plans (EGADS, a LONG-EZ builder! Who let him in here!) Anyway, as a previous message stated, the original GU canard for the Long used UND glass cloth that was flagged into the spar troughs, so we can't make a comparision. However, the special performance Roncz canard for the Long does use the 3 inch unidirectional tape. The plans for the Roncz canard just say to fill up the troughs and pay no attention to the number of plys. I think I know why Rutan decided to go that way. The Long-EZ spar and wings also use the 3 inch tape. Rutan originally called out the number of plys required for these parts. Later, he had to make a mandatory plans change and added to the total number of plys because he found some tape had less glass in it than his original test samples. In the case of the newer canard, just filling up the troughs with as much tape as they will hold solves this problem. Seemed like a good idea, so that's what I also did for the wings and centersection spar. I have no idea how many plys are in those parts. I just layed up the proper number of plys called out in the plans and the mandatory change. I then added whatever it took to fill up the troughs. That gave me more than was required and in case of the centersection spar, much more. Either I cut my troughs too deep, I got some lightweight tape, or my squeeging technique was more thorough than Rutan anticipated. You can pull alot of excess epoxy out of spar troughs with some diligent effort and a hair dryer. Now for something completely different - I checked on the engines that EAA Aviation Foundation has up for bid (mentioned in the last Sport Aviation). Not an O-320 or 360 in the bunch. They have one O-235C, one O-290G, a couple O/GO-435's, a bunch of GSO-480's, two Cont R975-C1's (from battle tanks!) and some other misc stuff that wouldn't be suitable for our aircraft. The one interesting thing was a "grab bag" of misc AN hardware - 300 lbs worth! Includes a large number of bolts of several sizes, star washers, zerk fittings, etc., all NOS hardware in original bags & boxes. But what with the bogus fastener scare, who knows..... If anyone wants a fax of the listing and bidding instructions, send me private email with your fax nbr. Stet Elliott Perpetual Long-EZ builder Date: Mon, 28 Aug 1995 13:44:37 -0400 From: Marcnadine@aol.com Subject: Canard Spar short on plys I ran into a little problem yesterday when laying up the top spar cap and am wondering if someone else has had the same problem. Last week I did the bottom spar cap layup and was able to fit 9 plys of uni-tape in the trough. Then yesterday when I did the top spar cap, I ran out of tape after the 8th layer. I ended up peel plying the layup and calling it a day. I called Larry today at Feather Lite (the maker of the foam core) and was told that adding the final layer will be OK, it that the canard if so overbuilt. He said that they do testing up to 12 Gs, on reject canards, before they break. Hope he's right. Marc P. N525CZ (1.38.193.5/16.2) id AA21104; Mon, 23 Oct 1995 15:53:02 -0400 From: "Volk, Ray" Subject: Canard Spar Cap Fill Date: Mon, 23 Oct 95 12:39:00 PDT Encoding: 20 TEXT I laid up my bottom Canard Spar Cap this past week end and after removing the peel ply and measuring over it's full length with the template, I noticed some dips below the ideal contour from front to rear of the slot of up to approximately .050 inches. This was especially true about 6 inches inboard of the two lift tabs. This theoretically could be filled with a few short strands of Spar tape, some UNI, flox, or nothing. The plans seem to indicate no micro on the spar cap. Question? Did anyone else have this problem and if so, should this be filled before applying the skin. and if so, with what? Ray Volk rvolk@space.honeywell.com From: Marc J. Zeitlin Subject: Canard Spar Cap Fill (fwd) Date: Mon, 23 Oct 95 17:16:01 EDT Ray Volk writes: >I laid up my bottom Canard Spar Cap this past week end and after removing >the peel ply and measuring over it's full length with the template, I >noticed some dips below the ideal contour from front to rear of the slot of >up to approximately .050 inches. This was especially true about 6 inches >inboard of the two lift tabs. > >This theoretically could be filled with a few short strands of Spar tape, >some UNI, flox, or nothing. The plans seem to indicate no micro on the spar >cap. > >Question? My $0.02 (I should put that in front of all my replies) or $0.05, as the case may be: 1) As long as you have a smooth transition from the spar cap to the foam, you will be able to glass the canard skin. Inboard of the lift tabs, the canard will be totally inside the fuselage, and I don't think that the aerodynamics will matter :-). Foam filler will go on the top surface, and on the bottom inside the fuse, who cares? 2) I had some flat spots (nothing ABOVE the template) as well, although I don't think any were over 0.030" deep. I glassed the skin over the spar cap, and filled to the contour with micro. 3) Jim White (I thought in the archives, but possibly in personal email [or else in my imagination]) mentioned a technique which I have not tried: Fill the cap OVER FULL with tape, and then use a power sander (GENTLY!!!) to bring the contour down to the template shape. Then, when you lay up the skin, you're perfect. 4) DON'T put micro between the cap and the skin - it has no structural integrity. Flox, in this case, would be unacceptable as well. If I was going to fill it with glass, I'd use extra tape, or UNI at the least. (Micro over the skin would be the lightest, but probably the most work). -- Marc J. Zeitlin Email: marcz@an.hp.com Date: Tue, 24 Oct 95 09:53:52 EST From: "Wilhelmson, Jack" Encoding: 13 Text Subject: Re: Canard Spar Cap Fill Ray: The "problem" you describe is common, I have built two canards and these low spots occur primarily because the taper of the spar cap slot must be greater than the thickness of the glass, other wise, the canard surfaces would have to be built up to match (you could not remove the excess glass without weakening the canard at a critical point) and this would change the canard airfoil shape which is critical to the flight characteristics. In any case, if they are inside the lift tabs, they are not going to be a aerodynamic problem, and they are going to be under the canard fairing, therefore they are not a problem. Date: Mon, 4 Dec 1995 21:55:29 -0500 From: StetsonE@aol.com Subject: Re: Templates In a message dated 95-12-02 22:44:04 EST, you write: >> The canard templates received with my set of plans were not identical >> in particular around the leading edge (the most critical area). >> According to the long-eze fraternity this is a known problem and >> should have been rectified long before our plans were ever issued. I'm >> not sure which one is correct A or B. First, I'm assuming the Roncz canard plans for the Cozy are identical to those for the Long-EZ. If this is so, then the following article is pertinent. It's from RAF's October 1985 Canard Pusher Newsletter 46: --------------- The New Roncz 1145MS Canard - Hotwire templates A and B are supposed to be identical. A few builders have reported that Template B is slightly larger than Template A. We have checked a bunch of plans here at RAF and have found this to be true in a few cases. We believe this must be due to paper shrinkage or offset printing variation. In our checking we have found Template A to be more consistently correct and we advise you to use A as the master, clamp A and B together and file them both as a pair down to be identical to Template A. --------------- I hope this helps. Stet Elliott Perpetual Long-EZ builder