Date: Sat, 09 Jan 1999 14:06:45 +0100 From: Jean-Jacques CLAUS Subject: Re: COZY: Canard Spar Jannie Versfeld wrote : > Dear All > > I could only cram 9 plies in to get a smoot contour. I shortened the > layers every 5" with a 45 > deg cut-off and ended just outboard of the lift tabs? I did exactly the same. Jean-Jacques CLAUS Cosy F-PJJC ( Reserved ) From: lschuler@cellular.uscc.com Date: Mon, 11 Jan 1999 17:29:35 -0600 Subject: Re: COZY: Canard Spar Jannie Versfeld wrote: >Just completed he bottom spar cap on the canard. I would like to know >how many plies of 3" uni tape should go in. I could only cram 9 plies >in to get a smoot contour. I shortened the layers every 5" with a 45 >deg cut-off and ended just outboard of the lift tabs? Would like to >hear some opinions just to clear my mind. First, 9 plies on the bottom sounds about right from memory. You need more on top than bottom. Not sure if I read your note correctly (I hope NOT). The spar cap needs to run full length; including between the lift tabs. I over-filled my cap trenches very slightly, then after cure, I re-taped the foam along side the cap with duct tape and using a belt sander with 80-grit and a light touch, I sanded the cap to match my curvature template. Worked extrordinarily well and had very few minor indentations that needed micro-fill AFTER the skin was on. I had to pick a bit of torn tape and sticky stuff particles off the foam before skinning, but seemed like a cheap price to pay for excelent curve and depth. Larry Schuler Date: Tue, 12 Jan 1999 08:04:16 -0500 From: bil kleb Subject: Re: COZY: Canard Spar lschuler@cellular.uscc.com wrote: > > I over-filled my cap trenches very slightly, then after cure, I re-taped > the foam along side the cap with duct tape and using a belt sander with > 80-grit and a light touch, I sanded the cap to match my curvature template. i tried this as well, but determined that you really need a variable- speed belt sander to do this job properly. also, you have to be careful not to get the glass hot, or the foam underneath will start expanding, making your caps thinner than they should be. however, my main objection to this method is that now i don't really know how many layers i have on the spar caps and some of the top-most layers are just dead weight since they were most likely cut at various points along the spar due to slight waviness or sanding irregularities. -- bil From: lschuler@cellular.uscc.com Date: Tue, 12 Jan 1999 09:20:55 -0600 Subject: Re[2]: COZY: Canard Spar bil kleb wrote: >i tried this as well, but determined that you really need a variable- >speed belt sander to do this job properly. also, you have to be >careful not to get the glass hot, or the foam underneath will start >expanding, making your caps thinner than they should be. >however, my main objection to this method is that now i don't really >know how many layers i have on the spar caps and some of the >top-most layers are just dead weight since they were most likely cut >at various points along the spar due to slight waviness or sanding >irregularities. My belt sander is variable speed; and you are right about that providing better control; wouldn't do it otherwise. Thanks for mentioning that. Can get hot as you pointed out; trick is to know that and accomodate it. I moved along the spar somewhat to allow some cooling; never got warm enough to be of concern for me at all. Don't really want to stay in one area too long anyway; would defeat the intent of smooth taper... Don't think I mentioned this, but I did final finish/touch-up with some 60 grit glued to a short wood block (a piece of 2x4 about 4" long). As for the foam expanding/contracting, as long as the temp doesn't get out of control (permamnent deformation), I don't think it's much of an issue. Especially considering that we have now gone from sanding pencile lines in half when making templates to splitting the difference between two grossly mis-matched drawings. I'd be more concerned about making A and B templates identical and without twist relative to each other than some tiny foam heat expansion and cooling contraction (if temp gets over the Tg of the foam or epoxy; then it's time to worry). As for the number of layers 'left': my 'overfill' essentially amounted to extending the layer which would be cut, a couple inches further out on the span and not killing myself trying to achive best contour while simultaneously doing a wet layup; that's all. I ended up with one more layer at the center section than was required to fill the trench. Those extended ends and the extra ply at center are the only glass touched by the sander. Primary structure (plies required to fill the trench) is not affected in any way. Think about it: If you add a layer that is not needed for the structural integrity, then sand it (or most of it) off, what is gained or lost in the structure? Remanants of partial strands and an ounce or two of weight is the price for perfect contour, near zero finish work and probably stronger overall structure due to zero hills/valleys at fore and aft edges of the caps. The idea was to: a)taper the layups both longitudinaly and laterally a bit nicer than can be done simply by cutting the ends off at 45 deg; b)to eliminate any very minor hills/valleys at the surface contour; and, c)provide perfect contour after the skin is on that required little if any fill, especially at the fore and aft edges of the trench as is normally necessary per other's statements. If memory serves, there is no call out in the plans for just how many UNI plies are 'required' on either top or bottom. Just says to fill the trench to contour. Which is what I ended up with; not much more and certainly no less. Worked extraordinarily well for me. I plan same with wings (for now anyway; not there yet). As always, info is offered FYI/FWW only. Worked for me. Larry Schuler From: "Bill Kastenholz" Subject: Re: COZY: Canard Spar Date: Tue, 12 Jan 1999 10:51:59 -0500 >lschuler@cellular.uscc.com wrote: >> >> I over-filled my cap trenches very slightly, then after cure, I re-taped >> the foam along side the cap with duct tape and using a belt sander with >> 80-grit and a light touch, I sanded the cap to match my curvature template. > >i tried this as well, ... > >however, my main objection to this method is that now i don't really >know how many layers i have on the spar caps and some of the top-most >layers are just dead weight since they were most likely cut at >various points along the spar due to slight waviness or sanding >irregularities. > > I didn't use a belt-sander, mostly because I don't have one. I hand sanded the cap down to match the foam. The number of layers don't make a difference, the thickness is the determining factor. As long as you squeege well, the correct number of strands will fill the trough. After doing all 8 spar caps, I would recommend the following: 1. Don't work alone on these layups, 2 or 3 people works well. 2. Make sure the material is warmed up, not just the epoxy. 3. Instead of a hair dryer, use a hobby heat gun. Even though it is rated at a lower wattage, it concentrates the heat better. Mark Beduhn told about this tool at Oshkosh, and I like it. 4. Use some sort of strapping tape to protect the foam, NOT duct tape. The epoxy expands to cover the tape and makes the tape difficult to remove. A strapping tape would have better strength for pulling out. Bill Kastenholz From: cdenk@ix.netcom.com Date: Tue, 12 Jan 1999 16:57:48 -0600 (CST) Subject: Re: COZY: Canard Spar Kastenholtz said Fiberglass strands require a length to develope their strength, much like when you grip a rope with 2 hands. I don't know what this length, for concrete reinforcing bars it might be 24 diameters or more, and more if the bars are bundled together. When sanding wavy strands, the strands require additional length from their ends to develope their strength. This is unlikely to be an issue if the the strands are reasonably straight, if they are not, other criteria also become an issue. Careful of hot guns for heating, they could locally overheat the epoxy. I would prefer to stick with a low temperature gun, and even then keep it moving. Date: Wed, 13 Jan 1999 08:28:57 -0500 From: bil kleb Subject: Re: COZY: Canard Spar cdenk@ix.netcom.com wrote: > > Careful of hot guns for heating, they could locally overheat the epoxy. correct. > I would prefer to stick with a low temperature gun, and even > then keep it moving. exactly. i use an old monokote heat gun from my r/c airplane days. it has an adjustable air inlet to control the heat/flow output which is typically lower than the standard hairdryer. -- bil From: "Bill Kastenholz" Subject: Re: COZY: Canard Spar Date: Wed, 13 Jan 1999 17:22:57 -0500 >cdenk@ix.netcom.com wrote: >> >> Careful of hot guns for heating, they could locally overheat the epoxy. > > >> I would prefer to stick with a low temperature gun, and even >> then keep it moving. > Bill Kleb wrote: >exactly. i use an old monokote heat gun from my r/c airplane days. >it has an adjustable air inlet to control the heat/flow output >which is typically lower than the standard hairdryer. > >-- Actually, this is a heat gun for monokote use, from a hobby store! But, I have a question. How hot can the epoxy get before "overheating" it? Exotherm was not a problem. Bill Kastenholz > From: Wayne Hicks Subject: COZY: Brock Canard Lift Tabs Date: Thu, 14 Jan 1999 10:35:43 -0500 FYI: I received my Chapter 10-12 Brock hardware today. There's a scratch across the surface of one of the lift tabs (NC-2, do I have the correct lingo?). The scratch is as if the surface was gouged with a small nail. Furthermore, the scratch is the entire length on the long axis of the lift tab, coincidentally going though the center hole at the bottom and the hole at the top. (Just my luck, huh?) It's NOT a superficial scratch and I don't think it can be removed by 220 grit sandpaper...and you know that the plans say "Don't you dare scratch" the lift tabs. I plan on calling Brock for replacements as soon as the clock strikes 10:00 AM Pacific time. In the mean time, a few questions: 1. Have any of you experienced this? 2. Have any of you made your own lift tabs, particularly from thicker stock? 3. Should I etch and prime any of this Brock hardware, or does Brock's processing take care of that for me? __________________________________________ L. Wayne Hicks SpaceTec Sr. Engineer 3221 North Armistead Ave 757-865-0900 phone Hampton, VA 23666 757-865-8960 fax http://www.spacetec-inc.com From: lschuler@cellular.uscc.com Date: Thu, 14 Jan 1999 10:32:01 -0600 Subject: Re: COZY: Brock Canard Lift Tabs Wayne Hicks wrote: >1. Have any of you experienced this? Had some minor scratches that I was able to remove, but nothing major (yet). Sounds like you got a bad one. Ken's been fairly nice to me; he may offer to send you a replacement right up front at his cost. >2. Have any of you made your own lift tabs, particularly from thicker >stock? Check the archives, but I seem to remeber that some have gone to 1/4" thickness. Cozy Europe uses 1/4" FWW. >3. Should I etch and prime any of this Brock hardware, or does Brock's >processing take care of that for me? I talked with Brock folks and most of their stuff is not primed or finished in any way and NONE of the aluminum parts are. At best they go through a de-burring tub which leaves them looking like they were plated or something. (That's why I called them.) I alodine "all" my aluminum parts; including the stuff I get from Brock. Larry From: cdenk@ix.netcom.com Date: Thu, 14 Jan 1999 16:46:37 -0600 (CST) Subject: Re: COZY: Brock Canard Lift Tabs If the scratch can be polished out with 220 grit or finer, I would use it if replacement is difficult. The scratch is parallel to the lines of stress which is good. Perpendicular would be not good, and probably good reason to reject. I don't think Brock does any surface treatment on these pieces, but it would be a good idea to alodine the pices, and then zinc chromate and paint whats sticking out when the canard is painted. Date: Fri, 15 Jan 1999 18:31:49 -0500 From: "Marc J. Zeitlin" Subject: Fwd: COZY: Brock Canard Lift Tabs Wayne Hicks; >...... It's NOT a superficial scratch and I don't >think it can be removed by 220 grit sandpaper...and you know that the plans >say "Don't you dare scratch" the lift tabs. In this case, I'll be more conservative than Carl D. :-). Unless you can EASILY completely remove this scratch, get a new on (for free) from Brock. They should never have sent it to you. You've got a stress concentration inherent in the bolt hole (around a factor of 3, IIRC) and the last thing you want is another stress concentrator (cracks can be stress concentrators of factors of 50 or more) right at the place where you've already got the most stress. When Nat says don't scratch these tabs, there's a good reason - your butt is hanging from those two bolts. -- Marc J. Zeitlin marcz@ultranet.com http://www.ultranet.com/~marcz/ From: Wayne Hicks Subject: COZY: 1/16th off Canard Fishtail Date: Tue, 26 Jan 1999 15:11:23 -0500 Okay: So I'm moving on to Chapter 10 and I'm reading the archives. I understand all the commotion about needing to take off the 1/16th inch from the fishtail for elevator clearance. I just want to clarify something. Are the canard templates in the 2nd edition of the plans (#501 and up, tan covers) corrected to already include the 1/16th inch or do I need to modify the fishtail portion? __________________________________________ L. Wayne Hicks SpaceTec Sr. Engineer 3221 North Armistead Ave 757-865-0900 phone Hampton, VA 23666 757-865-8960 fax http://www.spacetec-inc.com Date: Tue, 02 Feb 1999 10:40:58 -0700 Subject: COZY: Cozy: 3" UNI Tape From: "Thomas Kennedy" Dear Spar Cap Builders: The 3" UNI tape that is used in spar cap layups used to be in fact a full 3" wide. I recently went to ACS and almost got a roll now 2-1/2" wide. ACS was very nice tried to wet it out to show that it would widen up to 3" wide (it didn't, but it was a nice try). I said heck on them and ordered it through Wicks. When my order came, I got the same 2-1/2" wide stuff. Called Wicks and they refered me to ACS! It turns out that ACS is the sole fabricator of this item and they are manufacturing it to some MIL spec and are not about to change it. They cannot explain why it is now narrower, but insist that the same amount of material is still being used. Go figure. Anyway, called Nat, he said that he was recently made aware of the problem by another builder and would like to know what I found out (hence this letter). Per Nat, we still need to fill the trough in the 3" wide dimension. This may entail laying in the narrower plies and squeeging them to bleed out to fill the 3" wide spar cap widths or laying in an additonal 1/2 inch of material with each layer, the important thing is to fill the troughs and that if it takes more layers , well it takes more layers. Do not make the trough deeper and 2-1/2" wide. OK the prize inside. There may still be a narrow window of opportunity here. ACS is charging the low low price of 70 cents a FOOT. When I bought my original roll, I think I paid 80 cents a yard. WICKS STILL HAS IT (or did) for 70 cents a YARD. This probably won't last so if you are at all in the market for Spar cap tape, I recommend that you pick up a couple of rolls (180 yds) fast before the price goes up 3x. Sincerely hope this helps. Thomas Kennedy #248 finishing up Spar Just about to start on wings From ???@??? Tue Feb 02 18:45:36 1999 Return-Path: owner-cozy_builders@betaweb.com Received: from twc2.betaweb.com (majordomo@betaweb.com [206.43.209.18]) by acestes-fe0.ultra.net (8.8.8/ult/n20340/mtc.v2) with ESMTP id OAA15637 for ; Tue, 2 Feb 1999 14:38:48From ???@??? Tue Feb 02 18:45:36 1999 Return-Path: owner-cozy_builders@betaweb.com Received: from twc2.betaweb.com (majordomo@betaweb.com [206.43.209.18]) by acestes-fe0.ultra.net (8.8.8/ult/n20340/mtc.v2) with ESMTP id OAA15637 for ; Tue, 2 Feb 1999 14:38:48 -0500 (EST) Received: (from majordomo@localhost) by twc2.betaweb.com (8.8.5/8.8.5) id OAA19164 for cozy_builders-list; Tue, 2 Feb 1999 14:35:07 -0500 X-Authentication-Warning: twc2.betaweb.com: majordomo set sender to owner-cozy_builders@betaweb.com using -f Received: from ndcrelay.mcit.com (ndcrelay.mcit.com [166.37.172.49]) by twc2.betaweb.com (8.8.5/8.8.5) with ESMTP id OAA19159 for ; Tue, 2 Feb 1999 14:35:03 -0500 Received: from omta2.mcit.com (omta2.mcit.com [166.37.204.3]) by ndcrelay.mcit.com (8.8.7/) with ESMTP id TAA28704 for ; Tue, 2 Feb 1999 19:28:11 GMT Received: from localHost ([166.34.97.45]) by omta2.mcit.com (InterMail v03.02.05 118 121 101) with SMTP id <19990202192827.UQFG5654@localHost> for ; Tue, 2 Feb 1999 13:28:27 -0600 Date: Tue, 02 Feb 1999 13:28 -0600 (CST) From: Michael Pollock X-Mailer: MailRoom for Internet v2.3b (www.SierraSol.com/SierraSol) To: Cozy_Builders Subject: Re: COZY: Cozy: 3" UNI Tape Message-Id: <19990202192827.UQFG5654@localHost> Sender: owner-cozy_builders@betaweb.com Precedence: bulk Reply-To: Michael Pollock X-UIDL: 160cd18cf4880ab2eae19f4aeefad250 Thomas Kennedy wrote: >The 3" UNI tape that is used in spar cap layups used to be in fact a full 3" >wide. I recently went to ACS and almost got a roll now 2-1/2" wide. ACS was >very nice tried to wet it out to show that it would widen up to 3" wide (it >didn't, but it was a nice try). I had the same problem with my canard spar cap tape. It was also 2 1/2 inches wide. My carry-through spar cap tape was 3" wide. It was exactly the same part number from Wicks. I counted the uni fibers in both rolls, and there are exactly 30 uni fibers in each. It appears to me that whoever spooled the spar cap tape on the rolls kept the tension too tight on the spooler which caused the fibers to stretch and pull closer together. In any case, the 2 1/2 in wide spar cap tape works fine if one alternates which side the tape will butt up to. I got 10 layers of this 2 1/2 spar tape into my bottom canard spar cap. I let it cure and sanded the top down for a good contour. It turned out great. The bottom canard template fits perfectly over the bottom of the canard over the entire span. From: Lee810@aol.com Date: Tue, 2 Feb 1999 16:04:46 EST Subject: Re: COZY: Cozy: 3" UNI Tape In a message dated 2/2/99 12:22:47 PM Mountain Standard Time, jackson@cecer.army.mil writes: > Check out the following URL and tell me if this tape meets the specifications. > > Its available in 3" widths at 5 mil thickness. > > http://www.deltronix.com/public/acp/acp-tape.htm This doesn't look like a good deal. Aside from it being a non-approved material, the weight specification for the above 5 mil material reference above is approximately 3 oz./sq. yd. The ACS and Wicks tapes are 25 mils thick (.025") and weigh 22 oz./sq. yd. which is more than 7 times the weight per sq yard. At a cost of $1.50 per yard for the product mentioned in the above posting, it costs more than 16 times as much as the ACS or Wicks product pound for pound. I suppose that if ACS now owns the tooling and tripled the price by making it .70/ft instead of .70/yd, then the difference would only be about 5.3 times as much. The Cozy MKIV needs 282 yards of the 3" UNI tape which is going to cost $197 at the .70/yd price or $592 if the original posting is correct and ACS just decided to triple the price. The unit of measure is conspicuously absent on the ACS web site but is still listed as yards on Wicks web site. By comparison, the equivalent amount of the tape referenced from the above referenced web site would cost about $3000! Lee Devlin LongEZ N36MX Cozy MKIV under construction http://members.aol.com/lee810 Date: Wed, 03 Feb 1999 08:04:04 +0200 From: Rego Burger Subject: COZY: 3" UNI Tape Now you guys can guess why I made my "RIG" in one of Nat's old newsletters around 1992 or 93. (sitting at work) 30 rolls of roving with NO cross weave, two simple clamps to pull them and lay over the trough. Not having seen the 2,5" tape it is possible the cross weave has been woven in such a way that it narrows things a bit. Check to see if their are 30 strands of roving of about 0.16" cross-section. ( as a guide). Each of these rovings are made up of up to and more than 500 filaments of between 9 and 19 micron...a bit difficult to check with the naked eye. ( the 9 being stronger ) If so once the cross weave has been pulled out it should flatten with some squegee work! Make a test trough about 12" long in some spare foam and test it as a confidence booster...you can then decide if it will work without messing up a good part on your aeroplane. Hope you get it sorted out. Happy Building Rego Burger RSA Date: Tue, 02 Feb 1999 20:41:14 -0500 From: Jeff Russell Subject: Re: COZY: Cozy: 3" UNI Tape  

Thomas Kennedy wrote:

Dear Spar Cap Builders:
The 3" UNI tape that is used in spar cap layups used to be in fact a full 3" wide. I recently went to ACS and almost got a roll now 2-1/2" wide. ACS was very nice tried to wet it out to show that it would widen up to 3" wide (it didn't, but it was a nice try). I said heck on them and ordered it through Wicks. When my order came, I got the same 2-1/2" wide stuff.
As long as there is 30 strands in the tape,  just pull out the cross
threads and as you wet them out the 2.50 wide will go to 3.00.
ACS needs better QC on what they make and sell.  I have seen
this machine and it's a beast to set up and get it right :-)
 
--
Jeff Russell/AeroCad Inc.                    E-mail:   Jeff@aerocad.com
2954 Curtis King Blvd.  Ft. Pierce, FL. 34946
Shop# 561-460-8020 7:00am to 3:30pm  Home# 561-344-6200
Website:   http://www.Aerocad.com
Composite workshop info:   http://www.Sportair.com
  From ???@??? Wed Feb 03 22:09:45 1999 Return-Path: owner-cozy_builders@betaweb.com Received: from twc2.betaweb.com (majordomo@betaweb.com [206.43.209.18]) by acestes-fe0.ultra.net (8.8.8/ult/n20340/mtc.v2) with ESMTP id WAA03203 for ; Tue, 2 Feb 1999 22:17:27 -0500 (EST) Received: (from majordomo@localhost) by twc2.betaweb.com (8.8.5/8.8.5) id WAA27938 for cozy_builders-list; Tue, 2 Feb 1999 22:07:54 -0500 X-Authentication-Warning: twc2.betaweb.com: majordomo set sender to owner-cozy_builders@betaweb.com using -f Received: from imo12.mx.aol.com (imo12.mx.aol.com [198.81.17.2]) by twc2.betaweb.com (8.8.5/8.8.5) with ESMTP id WAA27928 for ; Tue, 2 Feb 1999 22:07:29 -0500 From: Cozy7971@aol.com Received: from Cozy7971@aol.com by imo12.mx.aol.com (IMOv18.1) id 2FGVa04794 for ; Tue, 2 Feb 1999 21:55:18 +1900 (EST) Message-ID: <5abf64e8.36b7ba96@aol.com> Date: Tue, 2 Feb 1999 21:55:18 EST To: cozy_builders@canard.com Mime-Version: 1.0 Subject: Re: COZY: Cozy: 3" UNI Tape Content-type: text/plain; charset=US-ASCII Content-transfer-encoding: 7bit X-Mailer: AOL 4.0 for Windows 95 sub 236 Sender: owner-cozy_builders@betaweb.com Precedence: bulk Reply-To: Cozy7971@aol.com X-UIDL: 38cb8108bcc17d8289848c5b5833053e In a message dated 2/2/99 12:47:46 PM Central Standard Time, tmkpida@pacbell.net writes: << The 3" UNI tape that is used in spar cap layups used to be in fact a full 3" wide. I recently went to ACS and almost got a roll now 2-1/2" wide. >> As another point on changing products, I just received 30 yards of BID from Wicks. It came without the selvage edge. I suspect this will make it a whole lot harder to do get the strands straight on a layup. To make things worse, the idiot that packaged it wrapped the roll with masking tape before rolling it up in paper. The tape stuck like glue and ruined about 1.5 feet of the roll. At $4.80 a yard thats pretty expensive packaging. On the positive side, after about six to eight months of turning the garage into a heated workshop I'm back in production. I'm finishing a few pieces in the basement and will be moving the plane outside for final assembly in a few weeks. Dick Finn From: "Paul Comte" Subject: Re: COZY: Cozy: 3" UNI Tape / Roving dispenser/wetter Date: Wed, 3 Feb 1999 09:46:13 -0600 Hi People, I had the opportunity to see a Defiant project being built in the Milwaukee area. (engines hung, strakes closed, wings glassed, 90% to go???). Very nice project, VERY big plane... The builder explained a piece of equipment in his shop as a roving dispenser / wetter. I had never seen one before. I had seen a picture of our friend from SA's roving dispenser but I did not remember that if it could wet out the roving too. Basically picture a 3" wide x 6' diameter steel roller mounted on a frame so its axle is horizontal. The frame has guides on each side so roving material is pulled across the top of the roller. The roller gets partially submerged in an epoxy bath. A wide razor blade is set (very carefully I am told) to allow an exact amount of epoxy to be available for wetting out the roving. The builder's description of pulling one of the larger caps reminds me of guard duty. Back and forth for eight hours. But then his project has _BIG_ caps... Has anyone seen a set of plans for this tool? I got the impression the one I was looking at was one-off construction. Best Regards Paul Comte Milwaukee, WI Date: Tue, 16 Feb 1999 12:41:36 -0700 Subject: COZY: 3 inch uni tape From: "Thomas Kennedy" Dear Cozy builders, In conclusion to a lot of background email on the issue I am happy to pass along the following: ACS has e-mailed me that the 3" ( really 2.5") tape will be sold at 70 cents a YARD and extra discounts per whole roll. You may have to argue a bit for the price as the book does not yet reflect it, but this is per Jerry Aguliar at ACS. Hope this helps. Thomas Kennedy Wing cores ordered. From: "John Slade" Subject: COZY: Dihedral Canard? Date: Sun, 28 Feb 1999 23:48:32 -0500 What's the feeling about these bent canards? I've search the archives and didn't find any discusson on them. A cozy builder told me at the weekend that they were both approved and recommended. Perhaps that was just for the 3 place. Have I missed something? John Slade, #757 (workbench built. Awaiting delivery of supplies) Date: Mon, 01 Mar 1999 08:44:49 -0600 From: "V. Atkinson" Subject: COZY: dihedral John, I'm the one who started the dihedral in the COZY. My original GU canard was unsatisfactory in the rain. Eleven years ago I decided to replace my GU canard with the Roncz. Nat Puffer did not have any plans for this, nor did he approve of it. At Oshkosh I happened to be sitting next to John Roncz at a seminar and asked him about my conversion work. He didn't think there was a problem with what I had shown him. In ending the conversation with John, he said the he had discovered about 1 to 2 per cent less overall airframe drag if the canard was built with a certain amount of dihedral. It seems that the tip vortices were impacting wing lift and therefore, drag. If your canard tips are up high enough, the drag is minimized. This came straight from Roncz himself. Now, I did pick up an extra 2 knots, but this may be due to less drag on the new canard, (its physically smaller), better building technique, better finish, or any number of other things. I don't know. But one of the positive things I did notice was the increased roll stability. I mentioned this to Mike Melville once, and he said "of course its more stable". I said "why don't you publish these things" He said "are you nuts". So much for furthering aviation. I successfully adapted the Long EZ Roncz airfoil to the COZY 3 and will send out the conversion instructions free to anyone who would like them. However, you will need the Long EZ addendum of the RMS 1145 canard plans to make it work. RAF no longer supplies these and if you cannot beg, borrow or steal a set of these plans, (from the Long EZ guys) I will sell you a set for $50.00. You can then make your own canard Nat Puffer has never officially approved this conversion. His policy is, if the designer hasn't done it to prove it, ITS NOT APPROVED !!!! An overall good policy. However, since its been on the plane 11 years now and has about 1000 hours on it, ( there are several others flying the bent wing canard) its pretty safe. Some of the people who have done the conversion don't do the dihedral. Those folks just wanted the benefit of the Roncz airfoil itself ( no pitching in the rain). The dihedral itself is actually polyhedral (center section is flat with the remaining outboard panels elevated). On the airplane it looks like dihedral as the flat center section is in the fuselage. I did this for ease of building and mounting. There is not much more work in making the canard bent vs. straight. Looks wise, I like the dihedral much better, it seems to go with the overall design. Good Luck Vance Atkinson From: "Nat Puffer" Subject: Re: COZY: Dihedral Canard? Date: Mon, 1 Mar 1999 09:11:50 -0600 Dear John, I suppose that builders would expect me to comment on your question and also Vance's post (which was very good). First of all, the opposite of stability is maneuverability. Many people like the latter. I haven't seen a fighter with dihedral for a long time. I have tremendous respect for both Vance Atkinson and John Roncz. I don't wish to start an argument, but even Vance suggested that a difference of 2 kts is very difficult to measure, and doesn't prove anything if you have made other drag reducing changes as well, so we are talking theoretical, I believe. Not to imply anything against John Roncz, but I think the R1145MS airfoil was his 5th try, so apparently he wasn't right (or optimum) the first few times. Also when I was sitting next to him one time, he suggested I test my airplane 5 inches past the aft c.g. I asked if that wasn't dangerous, and it said it sure is, and don't let your airplane get below 100 kts airspeed. Basically, John likes to experiment, particularly if someone else does the testing. Along a different line, the NACA scoop works because the sharp edges set up vortices that get rid of the boundry layer. Also those little turbulators they put on the GU canard set up little vortices that keep the air flow from separating in the rain (no one is really sure what is happening). So vortices can have a beneficial affect. I have heard it argued that with a straight canard, the tip vortices help to keep the airflow on the main wing from separating at high angles of attack and make the ailerons more effective. But we are talking about things that are very difficult to prove, even by someone as precise as Vance. Taking all this into account, the straight canard on Mark IV works very well (220 mph on 180 hp), so I have had no reason to build, test, or recommend a more complex canard, and I don't like to approve or be responsible for someone else's design changes. This keeps me out of trouble. One time I asked Burt why he didn't put a sweep in the canard like he did on the wings, and he gave me this real strange look. Regards, Nat ---------- > From: John Slade > To: Cozy Builders > Subject: COZY: Dihedral Canard? > Date: Sunday, February 28, 1999 10:48 PM > > What's the feeling about these bent canards? > I've search the archives and didn't find any discusson on them. > A cozy builder told me at the weekend that they were both approved and > recommended. Perhaps that was just for the 3 place. Have I missed something? > John Slade, #757 (workbench built. Awaiting delivery of supplies) > > > Date: Mon, 01 Mar 1999 12:08:44 -0600 From: "V. Atkinson" Subject: Re: COZY: dihedral Michael Amick wrote: > V. Atkinson wrote: > > > I'm the one who started the dihedral in the COZY. ... Looks > > wise, I like the dihedral much better, it seems to go with the overall > > design. > > Vance, > > One item I don't remember being touched on with the bent canard is > restriction to vision. Is it easier or harder to see under/over the > bent canard since it is moved up higher into your line of vision? > > Michael Amick Mike, I've had a few other ez drivers fly my COZY and its split between better or worse on the vision. The amount of vision is the same, and the dihedral doesn't intrude on your side vision, but its different. The canard no longer represents the horizon (although even the flat one had some bow in at cruise and during a 2 g pull out would probably be the same as mine during a normal cruise condition). Therefore, its just something you have to get used to that is different than the normal flat canard. Takes about one flight. One advantage that I discovered later, is that if you have a recognition or landing lite in your strake leading edge (you don't want to put one in the WING leading edge) the main beam will go under the canard instead of bouncing off of it. Vance Atkinson Date: Mon, 01 Mar 1999 17:13:09 -0500 From: Jeff Russell Subject: Re: COZY: dihedral Michael Amick wrote: > restriction to vision. Is it easier or harder to see under/over the > bent canard since it is moved up higher into your line of vision? I went from a straight to a bent R1145MS and as Vance said, it only took one flight to get the change of the up sweep. I have no problem using it as a horizon to fly by. Has anyone gone from a Straight R1145MS to a Dihedral R1145MS on a EZ type. It seems that all the people flying the bent canard went from a GU to a Ronce or just started a bent one at the start. I have done both where I had a GU on my Cozy and then went to a Straight R1145MS and then on my AeroCanard, I went from a Ronce to a Ronce that had dihedral. We saw only a rain change in the Ronce on the Cozy and no speed or roll change. It was also a larger span Ronce than the GU to change the flying CG of the airplane. The Straight to the bent (with the same length) on the AeroCanard showed a slight speed change for the better but a faster roll rate at the bottom end when your slow. I did not see any faster roll after 110 knots and up. Nat's comments and concerns are all very good. I feel that it is more complex canard that has more parts involved than the straight. I was looking for results that would be beneficial if I used the dihedral over the straight. I tested it's affect to our airplane and that's what I found. The bent canard stalls the same in all CG ranges. I still would like the GU better than the Ronce IF it had no rain change. -- Jeff Russell/AeroCad Inc. E-mail: Jeff@aerocad.com 2954 Curtis King Blvd. Ft. Pierce, FL. 34946 Shop# 561-460-8020 7:00am to 3:30pm Home# 561-344-6200 Website: http://www.Aerocad.com Composite workshop info: http://www.Sportair.com From: "John Slade" Subject: Re: COZY: Dihedral Canard? Date: Tue, 2 Mar 1999 09:46:48 -0500 Nat, Thanks. I really appreciate your comments on the bent canard. They make a lot of sense and, based on your recomendation I’ll think I'll stick with the straight & narrow. Incidentally, having seen both I prefer the look of the straight one. >I have had no reason to build, test, or recommend a more complex canard, >I don't like to approve or be responsible for someone else's design >changes. This keeps me out of trouble. this begs a question.... I want my airplane to be a COZY. If I were to get the plans for a bent canard from Vance and install one, does this constitute a major change? Would I have to call it something else? Just trying to see where the lines are. Thanks again for your thoughtful reply. John (My bench is ready and I've read Chap 3 three times. Where ARE those supplies?) Slade #757 From: "Nat Puffer" Subject: COZY: Bent Canards Date: Tue, 2 Mar 1999 11:51:18 -0600 People, For what it's worth I went through my reference books looking for discussions on dihedral. I could find nothing to support the proposition that it caused less drag, in fact what I found seemed to support the opposite. Lift is the force perpendicular to an airfoil. If the airfoil is horizontal, the lift force directly opposes gravity. If you add dihedral, the lift force is no longer vertical, so it has to be increased to keep the vertical component the same. This means you have to make the airfoil work harder (use more elevator). This means the induced drag increases, and drag opposes thrust. The result should be slower, not faster. It might also reduce your front seat load limit. Now, you have all heard the admonition to "keep the fibers straight". Well, when you put a bend in the canard, you are not keeping the fibers straight, so you are weakening the resistance to buckling, while at the same time you have added a bending moment because of the dihedral. Both of these are additive, so you have to increase the spar cap thickness. How much, would require a lot of calculating. If you don't make the spar caps thicker, you are giving up safety factor. Even though our design is very strong, we don't like to see anyone giving up safety factor. The other thing I ran across was that dihedral tends to increase dutch roll, a rocking motion which makes some people airsick. Thought I ought to mention these so you can make an informed decision. Best regards, Nat From: Todd Carrico Subject: RE: COZY: Bent Canards Date: Tue, 2 Mar 1999 12:54:13 -0800 You left out the increased complexity of construction. Vance mentioned it, and it caught my eye. He may be able to clarify, but it sounded like the hinge mechanism was more complicated than the straight. I also saw on AeroCads page that it was worth 5k's. I would think that 2 to 5k's would be tough to attribute solely to a canard change. What about AOI, length, airfoil shape, Atmospheric difference's during the test, workmanship, etc. Not that I have anything against the bent wing, or that I am partial to the straight. I was just thinking in text. Todd Carrico ... Thought I ought to mention these so you can make an informed decision. Best regards, Nat Date: Tue, 02 Mar 1999 17:00:16 -0500 From: bil kleb Subject: Re: COZY: Bent Canards Nat Puffer wrote: > > For what it's worth I went through my reference books looking for > discussions on dihedral. I could find nothing to support the proposition > that it caused less drag [...] this is due to your references: they do not account for interference effects of the wake (or tip vortex) on an adjacent surface. this appears to be the effect that john r is banking on. if the wing tip core goes below the main wing, this is bad; if it goes above, this is good. this is not a subject that references address since it is so geometry/situation specific. to account for such interference effects requires some heavy-duty math (e.g, the biot-savart law, cfd, etc.), some very careful tests, or A LOT of experience in the field supplemented by the preceding two. actually, if someone has both canards available and a canard-tip smoke system installed, the location of the cores relative to the main wing could easily be identified. anyone up for this test program? ;) -- bil From: cdenk@ix.netcom.com Date: Tue, 2 Mar 1999 17:18:58 -0600 (CST) Subject: RE: COZY: Bent Canards Todd said Several years ago, had a friends VZ impact the ground near vertical due to (YES it was a totally differnt setup than the Long and Cozy) a control failure. The elevators were originally used a ailerons. His had the linkage tied together to work together. Something broke and an uncommanded roll inverted crashing 20 feet from the shoulder of I-480 at Cleveland Hopkins Airport at rush hour. He only had minor injuries. The point - keep it simple (everywhere, not any specific item) - With repect to those who have done a good job to date. From: cdenk@ix.netcom.com Date: Tue, 2 Mar 1999 17:23:57 -0600 (CST) Subject: Re: COZY: Bent Canards Nat said <"keep the fibers straight"> Instead of buckling, I might be concerned with the top center, canard loaded, negative, with loads downward. In this loading the top fibers are in tension, trying to straigten. THis could cause delamination of the fiberglass. Haven't done any calculations, just suggesting this is an item to review. Date: Tue, 02 Mar 1999 21:35:31 -0500 From: bil kleb Subject: Re: COZY: Bent Canards Nat Puffer wrote: > > What you don't realize is that there are builders out there who think it is > wonderful idea to get 2 unproven knts by doing a dangerous thing, bending > their canards without increasing the spar cap thickness, and installing > universal joints in the middle of their elevator torque tubes without > having proven drawings to go by. i fully realize that. sounds like you need a word with vance, he's even a supported columnist for your newsletter... > Its my neck on the line, not yours. yep, your choice, but it cuts both ways. > I don't meddle in other people's designs, what a minute... i seem to remember some designer named rutan in your past.. ;) in my little world, i don't see myself as meddling with anyone's design, i am just presenting aerodynamics considerations as my limited brain knows them. > and I think it would be nice ediquette if other experts didn't > meddle in mine. not possible, this is the real world. everyone has an opinion, and thanks to this fine country of ours, they are allowed to voice it. in fact that is what this email list is all about... sharing opinions. and i, as well as many others, value your opinions highly and i thank you for sharing them with us... > I don't mean to offend you. you would have a very hard time doing that, i promise you. i apologize if i offended you... > You are probably very well educated. don't know about that. a little knowledge is dangerous, and we all only have a little. > I don't know what ;) means. My language is english. again i implore you to have a look at: http://members.aol.com/bearpage/smileys.htm my remark about testing with a smoke system in the canard tip was sarcasm. review a portion of our group's charter: 13) All members will endeavor to learn the cult of the "smileys" [ :-), ;-), <-), :-(, etc. ] so that they will understand and not misinterpret humor, sarcasm, irony, or less than subtle remarks. > Good. Just tell my builders that you have more years of aero education > than I do, so they should disregard my advise and listen to you. i haven't told fellow canard builders anything about my background, i leave that domain for carl denk. actually, i don't value formal education very highly. take as an example, john roncz---no formal college course for that one... humbly, -- bil X-Authentication-Warning: twc2.betaweb.com: majordomo set sender to owner-cozy_builders@betaweb.com using -f From: "D.A. Teigen Enterprises" To: Subject: COZY: Bent Canard Cost & Construction Date: Wed, 3 Mar 1999 14:06:51 -0800 X-Mailer: Microsoft Outlook Express 4.72.3110.5 Sender: owner-cozy_builders@betaweb.com Reply-To: "D.A. Teigen Enterprises" Fellow Builders, I have been monitoring this user group since I started construction of my Aerocanard in August of 1996 and this is my first post. The purpose of this post is to discuss the construction of my bent canard and its costs. I ordered my bent canard spar from Jeff Russell in March of 1998 at a cost of $475.00. I think the spar costs $485.00 today. I also ordered the precut canard cores as well as his wingtips. The total cost for the prefab parts (including the spar) was $646.64. I then had the same costs as the rest of the straight canard builders to finish construction, with the exception of the MS20271 B10 universal joint placed in the middle of the center section canard torque tube. The construction time was very close to a buddy of mine building a Cozy IV with a straight canard. As to the degree of difficulty for construction, I can't say it was any more difficult then the straight canard with the exception of building the jig to hold the canard during skinning. Anyone with a little common sense and any knowledge of woodworking could easily construct the jigs. Jeff's construction video is excellent and leaves no room for guessing as to how to do this. The adding of the universal joint was no harder then cutting the center canard torque tube, machining the ends and putting the universal in place. The rest of the hardware is standard issue from Brock, just as the straight canard. As to the cost of a pre made bent canard -- Jeff's posted cost is $2,100, which is a far cry from the $5k that someone posted earlier. I just reread the post to was 2k to 5K. I would have to totally agree with Vance's post about not taking off your straight canard to install a bent canard. I do not think the "average" pilot and builder is going to notice any tremendous performance increases. I built the bent canard for three reasons. The first, was that Jeff has successfully flow a bent canard for many hours, as well as Vance and others. Secondly, I did not have a straight canard already built and lastly, I think the wing tip vortices generated from the canard will miss the main wing at slower speeds. THAT'S A HUGE PLUS IN MY BOOK. As to the strength issue, remember that the dihedral of the bent canard is only 3 degrees. I do not think that such a minor dihedral is going to "increase Dutch Roll" like the early Bonanza's did or cause any significant weakness. My bent canard, as Vance's, is incredibly strong. Nat's discussion of the center of lift is accurate. The center of lift will be pointed to some imaginary spot way above the center of the fuselage. Going back to the general portion of my A&P classes, this should cause a more stable ride, not an increase in Dutch Roll, since the center of lift from both sides of the canard are trying to reach a common point centered above the fuselage. Dutch roll mainly comes in when the degree of the dihedral is as radical as the early Bonanza's. Cessna has place dihedral in the Centurions and Cardinals for may years with no adverse effects. Besides all this stuff, in my opinion the bent canard looks great!! Thank you for your time. Dave Teigen Aerocanard #24 From ???@??? Thu Mar 04 23:05:00 1999 Return-Path: owner-cozy_builders@betaweb.com Received: from twc2.betaweb.com (majordomo@betaweb.com [206.43.209.18]) by acestes-fe0.ultra.net (8.8.8/ult/n20340/mtc.v2) with ESMTP id KAA10743 for ; Thu, 4 Mar 1999 10:30:00 -0500 (EST) Received: (from majordomo@localhost) by twc2.betaweb.com (8.8.5/8.8.5) id KAA09159 for cozy_builders-list; Thu, 4 Mar 1999 10:05:41 -0500 X-Authentication-Warning: twc2.betaweb.com: majordomo set sender to owner-cozy_builders@betaweb.com using -f Received: from linus.spacetec-inc.com (linus.spacetec-inc.com [209.108.93.11]) by twc2.betaweb.com (8.8.5/8.8.5) with ESMTP id KAA09154 for ; Thu, 4 Mar 1999 10:05:32 -0500 Received: by linus.spacetec-inc.com with Internet Mail Service (5.5.2448.0) id ; Thu, 4 Mar 1999 09:55:38 -0500 Message-ID: <117DAEEB6D9FD211835B00A076A01808036294@linus.spacetec-inc.com> From: Wayne Hicks To: Cozy Builders Subject: COZY: Chapter 10 Lessons Learned Date: Thu, 4 Mar 1999 09:55:36 -0500 MIME-Version: 1.0 X-Mailer: Internet Mail Service (5.5.2448.0) Content-Type: text/plain; charset="iso-8859-1" Sender: owner-cozy_builders@betaweb.com Precedence: bulk Reply-To: Wayne Hicks X-UIDL: 250cd0580504e35d21057578dc9912df Here's my list of lessons learned from building my canard. Hope it helps those that follow. 1. Drill a hole through the pipes for the hotwire saw and use a screwdriver to tighten the wire. The clamping force of the pliers kept collapsing the pipe, causing the pipe would start to buckle under load. (bil kleb--> by my account, I owe you about 4 feet of pipe ;-( ) 2. I used aluminum angles screwed onto the 2x4's and butted up against the aft canard cores to jig them bone straight. I drilled holes every six inches for drywall screw on both sides surfaces of the angles. 3. Clamp a piece of angle to the metal strip jigs that hold the inserts into the aft cores during micro cure. This ensures that the lift tabs will be in line with each other and are perpendicular with the chord line. 4. Before slurrying the shear web, I temporarily stuck the wood dowels back into their holes to keep slurry from running into the holes. 5. It's faster to lop the slurry onto the shear web with a brush, then follow with a squeegee. 6. Before glassing the shear web, I measured the "perimeter" of the shear web at several locations and made a pattern. I laid up the slightly oversized, biased-cut UND (two layers at a time) on wax paper on my workbench, then trimmed to exact shear web dimensions. WORKED GREAT, no scissor trimming required! 7. I used 10 pieces of UND, not 9 for the shear web layups. My mileage obviously varied.... 8. Remove the nails (or drywall screws :-) ) and remove the cores from the jig before pulling off the peel-ply from the shear web. Otherwise, you might rip the cores from the bondo'd nails, making huge holes in the cores and ruining your day. 9. I used a drywall screw to pull the silicone plugs from the lift tab inserts. Screw the drywall screw into the silicon plug, apply gentle heat, and pull out in one piece. 10. Although the plans give you the "one inch wide" dimension for the high density foam inserts (elevator hinges), I didn't recognize that I could use full-size figures 19, 49, and the full-size M drawing to get the length, height, profile, and placement of the inserts. (this could be because I don't have a good feel for when something's being represented as full-sized, but it's more likely due to that I copy my plans onto 8x11's for shop work, notes, and scribbling so as not to destroy my originals.) 11. I used 10 tapes on the bottom spar trough and 11 tapes on the top. I didn't experience any problems with the 2.5 inch tape. These layups were FUN! I purposely overfilled the bottom trough slightly, but after going through the hassles of sanding down to contour, I made sure to do a better job of filling the top trough "just right". 12. Make the E and F templates out of 1-inch wide wood. In that manner, you can put the template on the canard and the level on the top of template without having to delicately balance everything. Else, the level falls off the template and punches a big ding into the canard foam. ____________________________________________________ L. Wayne Hicks SpaceTec Division, Zel Technologies, LLC Sr. Engineer 3221 North Armistead Ave 757-865-0900 phone Hampton, VA 23666 757-865-8960 fax http://www.spacetec-inc.com http://www.zeltech.com From: Wayne Hicks Subject: COZY: One more Chapter 10 thing... Date: Thu, 4 Mar 1999 10:19:26 -0500 >From the plans, one of the canard cores is cut from one of the 64-inch blocks. Since one of the elevator cores is cut from that same block, I found it very convenient to lop off the whole section with the hotwire saw. In the next step, I lopped off the 13 (?) or so inches from the 64-inch piece. Then I cut across the whole length to cut away the canard piece from the piece for the elevator core. Well, guess what? My elevator core piece is 51 inches (because 64 minus 13 equals, yada, yada. yada...) instead of the 55 inches needed. Lesson learned---> Cut away the elevator core piece from the canard core piece first. Then lop off 13 inches from the canard core piece only. The elevator core piece gets cut differently later in Chapter 11. This is not a knock against the plans as I should have read ahead, but it sure seemed like the right thing to do at the time. It's very exciting to be finally hotwiring the cores and it's easy to get ahead of yourself. ____________________________________________________ L. Wayne Hicks SpaceTec Division, Zel Technologies, LLC Sr. Engineer 3221 North Armistead Ave 757-865-0900 phone Hampton, VA 23666 757-865-8960 fax http://www.spacetec-inc.com http://www.zeltech.com Date: Thu, 04 Mar 1999 09:26:58 -0800 From: hrogers@slac.stanford.edu (Howard Rogers) Subject: Re: COZY: Chapter 10 Lessons Learned Wayne Hicks wrote: >Here's my list of lessons learned from building my canard. >Hope it helps those that follow. >snip< >6. Before glassing the shear web, I measured the "perimeter" of the shear >web at several locations and made a pattern. I laid up the slightly >oversized, biased-cut UND (two layers at a time) on wax paper on my >workbench, then trimmed to exact shear web dimensions. WORKED GREAT, no >scissor trimming required! This is a great technique. It makes the whole process neat, and helps keep the fibers all oriented properly, and nice and straight. I have used it, in many places, but with one difference that I feel is important to point out. I would not use waxed paper, for the same reason that we are careful to not use waxed mixing cups. Wax can contaminate the epoxy. I have used heavy duty aluminum foil, brown kraft paper, and visquene polyethylene, though I am a little wary of that last one, because I have felt a "waxy" feeling stuff on the surface of some of it. My personal favorite is the heavy foil. One additional tip, is to use two pieces of foil, lapped about an inch, with the one that will wind up the unerneath foil piece folded back on itself like a pants cuff. This way, when you have lifted the glass into place, you can grab one foil piece and peel it off easily, while keeping the glass pressed down with a brush. The second piece will be easy to grab, because of the folded "cuff". I used this method for every bias taped seam, once I learned it, as well as for the winglet/wing attatch layups, and in countless other places. Try it. You'll like it! Howard Rogers Date: Sun, 07 Mar 1999 16:28:50 -0600 From: David Domeier Subject: Re: COZY: Bent Canards Bill, Re "actually, if someone has both canards available and a canard-tip smoke system installed, the location of the cores relative to the main wing could easily be identified. anyone up for this test program? ;)" It was tested on the Long EZ years ago. I once read that the canard vortex struck the wing on the up roll adding to wing lift and in effect cancelled the induced drag of the canard. I think NASA did the tests. It would seem the effect would be a function of airspeed,i.e., the vortex roll pattern and how it struck the wing would be subject to how fast the machine was moving. I do not recall at what speed that test result was based on, but I definitely remember reading it. dd Date: Mon, 08 Mar 1999 08:37:23 -0500 From: bil kleb Subject: Re: COZY: Bent Canards David Domeier wrote: > > bil kleb wrote: > > actually, if someone has both canards available and a canard-tip > > smoke system installed, the location of the cores relative to the > > main wing could easily be identified. anyone up for this test > > program? ;) i've had a few bites on this. it might behoove some to review the charter, specifically, 13) All members will endeavor to learn the cult of the "smileys" [ :-), ;-), <-), :-(, etc. ] so that they will understand and not misinterpret humor, sarcasm, irony, or less than subtle remarks. here's a decent catalog: http://members.aol.com/bearpage/smileys.htm > It was tested on the Long EZ years ago. `it' being the the canard tip vortex locations relative to the main wing. > I once read that the canard vortex struck the wing on the up roll > adding to wing lift and in effect cancelled the induced drag of > the canard. that is part of the story, yes. > I think NASA did the tests. yep, nasa langley even. nasa tp 2382 by long yip, march 1985 appears to be the most comprehensive. unfortunately long just moved offices and `recycled' all his old reports. however, as with all nasa reports, it is available from, ntis: http://www.ntis.gov/ (703) 605-6000 casi: http://netsrv.casi.sti.nasa.gov/ (301) 621-0390 (the nasa site is typically cheaper.) > It would seem the effect would be a function of airspeed, as you surmise it is a function of a bunch of variables. in summary, they took a full-size long-eze, stuck it in the tunnel, and tried to figure out what worked, what didn't, and why. they also played with configuration changes (winglets-no winglets, canard incidence, c.g. ranges, canard airfoil section, etc.). one configuration change was to mount the canard 15.25" lower "because of interest in improving pilot visibility." they found that for the normal canard location, canard tip-core impingement occurred between -1 and 3 deg aoa while with the canard mounted lower impingement occurred between 4 and 8 deg aoa. i have heard people typically sight that 2 to 3 deg is a typical cruise aoa. so, coupled with the above numbers, this indicates that the vortex almost clears the wing with the standard configuration. thus, with a little more help from dihedral, the cores would most likely pass above the wing. however, they also concluded that "placing the canard in the low position had little effect on lift, pitching moment, AND TRIMMED DRAG." thus, one might conclude that vance's reported 2 knot speed increase is at least debatable. long also gives a warning, "[a]lthough the static aerodynamic effects of moving the canard to a low position are small for this configuration, the dynamic effects of the canard tip vortex impingement MAY BE SIGNIFICANT in terms of handling characteristics." [emphasis added] -- bil Date: Mon, 08 Mar 1999 17:54:19 -0600 From: "V. Atkinson" Subject: COZY: [Fwd: dihedral] X-Mozilla-Status2: 00000000 Message-ID: <36DC80D8.4ADCB0F9@pop.flash.net> Date: Tue, 02 Mar 1999 18:22:48 -0600 From: "V. Atkinson" X-Sender: "V. Atkinson" <@mail.flash.net> (Unverified) X-Mailer: Mozilla 4.5 [en]C-FLASHNET (Win98; I) X-Accept-Language: en MIME-Version: 1.0 To: canard-aviators@canard.com Subject: dihedral Content-Type: text/plain; charset=us-ascii Content-Transfer-Encoding: 7bit Ok guys, what I didn't tell you was the master himself said he had accidentally discovered the reduced drag while playing around on something else on his computer. He VERIFIED it using some other calculations. If John Roncz sez so...its SO. The probability of Roncz being wrong is right next to zero, the rest of us schlock's have a pretty high probability of goofing up. After Roncz figures it out then there's the problem of transferring his masterful works into the finished product. I have included extra strength in the spar caps by deeping the spar troughs. My canard is so strong that you can lift the nose by the canard wing tip with no bend in the outboard panels. I would certainly not build a new canard just to have a bent one, the difference is not that noticeable. But when the great one suggests," if your gonna build a new canard anyway, put in the bend..........". and that's the rest of the story. Vance Atkinson Date: Tue, 09 Mar 1999 07:45:16 -0500 From: bil kleb Subject: Re: COZY: Bent Canards bil kleb wrote: > > in summary, they took a full-size long-eze, oops, sorry, that's vari-eze. (thanks jd) -- bil Date: Mon, 31 May 1999 11:49:52 +0200 From: "Rego Burger" Subject: COZY: Spar Cap - Rovings I made a total of 8 on my project. (Canard,main spar and each wing X 2) Then I decided to help Chris van Hoof with his canard and main spar. Canard finished ( another 2 now 10 ) and busy with his main spar cap this past weekend. Even using my "bobbin" machine, not having to deal with removing the cross threads, there had been the odd roving that would make life just that bit difficult for the prefectionist that pops up in me from time to time. ( generally I'm easy come easy go) The idea is to keep the rovings straight for maximum strength and the squeegee normally does the job quite well. However the odd roving sometimes rolls over another causing a cross over and it takes time to figure out which one at the end to pull on. I then saw my son coming the dog's hair on the lawn and ping! "All I need is a comb." A nice plastic comb with wide gaps about 1.5-3mm did the trick quite nicely. I trimmed it to about 2,75" to fit the trough nicely without jamming. Start at the centre once a ply is wetted and gentle "comb" either side. Nice straight rovings...far better than mine came out. Just don't be in a hurry and don't try it dry, it pulls too many filaments if not wet. I suggest if you have a chance to watch someone at work first you will save lot's of time and money. The plans are more than proffessional but it does not include all the tricks folks come up with. Never too old to learn hey? Is it worth the extra effort? I don't know, but it got the rovings nice and straight on my 11th cap far easier than I tried before. So I will use it on the 12th. :-) If it helps someone else, please try it. Régo Burger CZ#139 From: "james leturgey" Subject: COZY: bent 1145ms canard Date: Tue, 21 Sep 1999 10:44:46 PDT I thought I would post the results of my latest mod for the group to evaluate and comment on. Thanks to Vance Atkinson for his help and sketches, I was able to complete the new canard in just over two weeks. Then another three weeks for the painter to have time to do his thing (I don't spray urethane). Then wait another three and one weeks for the district inspector to look at it and sign me off for seven hours "in the box". Finally made the fist flight on the 17 of Sept with the mew canard. I'm still smiling after eight and a half hours of testing. With the stand GU canard I was getting about 147 knots at 8500 msl full throttle and leaned. The speed with the Roncz canard with 3" of dihydral increased to 155 knots at 8500 msl, leaned, 29.92 bm on the altimiter and 54 degrees oat. The plans stated that RAF experienced between 1 and 3 knots on the prototype. I can't explain it but I know it definatly that much faster. My engine is a 0235c1 and the mp was 20.7 at 2780 rpm in smooth air. The most rpm I could get with similar conditions with the GU canard was 2680. ______________________________________________________ Get Your Private, Free Email at http://www.hotmail.com From: "james leturgey" Subject: RE: COZY: bent 1145ms canard Date: Wed, 22 Sep 1999 06:42:00 PDT Hi Nick: I'd do it again the same way. The way the bend makes it look; and the performance gain may be attributed to the vortices being above the main wing. Building it was straight forward using Vance's method for gluing the foam together. It was quite easy to line everything up this way. The only problem I run into was making sure the control arms would not interfer with anything around the leg area and match up with the existing setup. I didn't want to have to re-rig my controls. I don't think the sealing of the tube was a problem as the tip of the canard is only 3" up from the center. I managed to reduce the air infiltration at the tube area significately due to the smaller arc of the tube on this hinge design. I did flox on to the canard small wedges that matched the tube arc and the fuselage both in front and arear of the tube just like the photo of Mark Zeitlin canard on his web page.This really helped close things up as I can feel no air on my legs. Then again the outside temps are not cold enough yet. Nice hearing from you again. Jim >From: "Ugolini, Nick" >To: 'james leturgey' >Subject: RE: COZY: bent 1145ms canard >Date: Wed, 22 Sep 1999 08:37:03 -0400 > >Hi Jim, >Congratulations on the new canard. I am planning to build a Ronz for my >cozy (replacing the GU) but I was thinking of the straight (easier to keep >lined up) and seals better around the tube.... > >What sort of problems did you have? Vances instructions are not so good and >I seem to remember it would be hard to seal the tube up properly... > >Nick > ______________________________________________________ Get Your Private, Free Email at http://www.hotmail.com Date: Wed, 22 Sep 1999 16:33:17 -0400 From: Jeff Russell Subject: COZY: Re: [c-a] bent R1145ms canard james leturgey wrote: > > [The Canard Aviators's Mailing list] > > I thought I would post the results of my latest mod for the group to > evaluate and comment on. Thanks to Vance Atkinson for his help and > sketches, I was able to complete the new canard in just over two weeks. Then > another three weeks for the painter to have time to do his thing (I don't spray > urethane). Then wait another three and one weeks for the district > inspector to look at it and sign me off for seven hours "in the box". > Finally made the fist flight on the 17 of Sept with the new canard. I'm > still smiling after eight and a half hours of testing. With the standard GU > canard I was getting about 147 knots at 8500 msl full throttle and > leaned. > > The speed with the Roncz canard with 3" of dihedral increased to 155 > knots at 8500 msl, leaned, 29.92 bm on the altimeter and 54 degrees oat. > The plans stated that RAF experienced between 1 and 3 knots on the > prototype. I can't explain it but I know it's definitely that much faster. > My engine is a 0235c1 and the mp was 20.7 at 2780 rpm in smooth air. The > most rpm I could get with similar conditions with the GU canard was 2680. We have been building and flying this style of canard for over 3 years now. We found a small speed change but saw the most change in slow speed roll. If anyone needs help on one of these canards give us a call. This is "not a Cozy approved mod". -- Jeff Russell/AeroCad Inc. E-mail: Jeff@aerocad.com 2954 Curtis King Blvd. Ft. Pierce, FL. 34946 Shop# 561-460-8020 7:00am to 3:30pm Home# 561-344-6200 Website: http://www.Aerocad.com Composite workshop info: http://www.Sportair.com From: cdenk@ix.netcom.com Date: Sun, 31 Oct 1999 13:30:50 -0500 (EST) Subject: Re: COZY: Canard hinge pin set screws P/N? GO to your local hardware, or industrial supply house, pay attention to the head, other end ( could be pointed, flat, serated teeth, etc, length, and of course diameter, thread. Date: Sun, 31 Oct 1999 15:20:13 -0500 From: Bulent Aliev Subject: Re: COZY: Canard hinge pin set screws P/N? David de Sosa wrote: > I stripped the head of one of my 10-32 set screws used to hold the hinge > pins in place on > the canard. I cannot seem to find reference to its' P/N in the Wick's > or ACS catalogs. > The plans reference P/N 222 (small screw thread locker) but this may > refer to the Loctite > P/N rather than the set screw. > > Does anyone know of a source for these screws or where they are in the > supply catalogs? > > Davd de Sosa > Cozy MKIV #080 I have mine still in the plastic bag from Wicks and they are marked: 8S1032 x 1/4 Bulent Date: Wed, 03 Nov 1999 17:07:34 -0500 From: Neil Clayton Subject: COZY: CS10 & CS11 weights The recent thread incenced me to cast my own elevator lead weights. Wonderfully successful! I got a chuck of lead roof flashing from Home Depot, and used a snall 3-in-1 oil can as the mold. After peeling off the steel skin from the can, Voila! A nicely shaped weight, just needing superficial machining to clean it up....and there's my question; What finished size (and therefore weight) are CS 10 and CS11 respectively? Does anyone have a set they can readily measure/weigh? I suspect they need fine tuning to balance the elevators after painting, but what's a good starting weight? Thanks in advance Neil C From: Militch@aol.com Date: Sun, 14 Nov 1999 21:58:35 EST Subject: COZY: Foam cutting templates I made the templates tonight for the canard. The first page of Chapt 10 tells you to cut the basic blocks needed from the 64" long foam using the straight-trim templates shown on drawing M-17. M-17 is the page I used for the various canard cutting templates (A - D), and it also includes a variety of templates for checking the canard during construction, but there aren't any straight-trim templates shown. I don't see anything that jumps out at me on the other drawings either. I assume I can do this with a couple of straight edges, but would appreciate it if someone could clarify this for me. Regards, Peter Militch #740 From: "John Slade" Subject: Re: COZY: Foam cutting templates Date: Sun, 14 Nov 1999 23:13:37 -0500 Peter, >straight-trim templates shown on drawing M-17. There are some straight templates somewhere in the drawings. I just used them for the wings. Maybe you have an off-cut of M17 lying around somewhere. I don't know which drawing they're on because mine are all cut up now. They're about 8 inches by 1.5 inches but, yes, you can use any straight edge that's as long as the cut plus about 1/2 inch at each end to rest the hot wire on. I bought a couple of 12 inch * 6 inch metal right angles (I think they're called set squares) from home depot and drilled them to take a nail every couple of inches. This worked well because the right angle comes in handy. I used these angles lots of times during my "hot wiring days". Regards, John Slade (just finished my last spar cap - ever) Cozy MKIV #757. http://kgarden.com/cozy From: jhocut@mindspring.com Date: Mon, 15 Nov 1999 07:29:30 -0500 Subject: Re: COZY: Foam cutting templates I'd suggest going to Big Lots or some other discount store and looking for some cheap steel rulers, I usually see them for around $1. Drill mounting holes about every inch and you're good to go. Jim Hocut Cozy Mk IV - ch 19 jhocut@mindspring.com