Date: Wed, 31 Dec 1997 19:51:18 -0500 From: Ian Douglas Subject: COZY: Shear Web Bubble Hi All, Second shear web is complete! I have to say that Peter and I DID check over the shear web about a million times before closing shop but to my dismay, I found a big air bubble the next morning in the lower spar cap trough about .15" high and about 1.5" x 2" in area (it does not get close to going around the corner onto the vertical. The biggest pain is that it is at the transition point from 4 layers to 2 layers of UNI. What I want to run by everyone is which of the following choices you would pick for repair: 1. Do as per the plans and cut it out with a 1" overlap of BID over the repair (I don't like this as it will cause a joggle in the spar cap at the repair point - since we go to all the trouble of removing the cross weave from the spar cap glass to make it lay PERFECTLY FLAT I'm thinking a joggle this size HAS to be bad). If I go with this I won't want to keep or even fly the plane as I sometimes like to stress to the limits when flying... 2. Cut out the offending layers while keeping the 45degree alignment of the weave and create a patch that will butt up against the glass left behind (same as when the butt joints are done during the origional layup). This will expand into the removal in length along the spar of almost a foot of glass on each side but!, will give me the peace of mind that the glass will be laid flat and will no longer require the BID over the repair area. This will also bring the strength back to 99.99% with NO joggle in the spar cap (no BID required). This is what I want to do, the amount of work involved is almost the same as constructing another wing, so a shove here is what I need / want ;-) 3. Make a new wing. -- Ian D.S. Douglas MK0069 Date: Wed, 31 Dec 1997 20:19:12 -0500 From: Ian Douglas Subject: COZY: Shear Web Bubble I just had another thought. I could cut the shear web off of the wing from the bubble to the tip and bond a new piece of foam on. Then just reglass the two 13" pieces back on. -- Ian D.S. Douglas Director of Technology Workplace Technologies Corporation If you write software, send me your resume! Date: Thu, 01 Jan 1998 12:45:05 -0500 From: Ian Douglas Subject: Re: COZY: Shear Web Bubble Hi All, Thanks for the good tips. Nat sent the following: > Dear Ian, > If I understand you correctly that the bubble is in the spar cap trough > and less than 39 inches from the tip of the wing, I think it would be okay > to just sand through the bubble so the spar cap has a flat surface to rest > on. The shear web layers do not really contribute very much underneath the > spar cap. But before you sand through it, why don't you try injecting some > epoxy into the bubble and then hold the bubble down with a real heavy > weight while the epoxy cures, and then if the glass isn't quite level, sand > it level. You could even slit the fiberglass layer a little if that would > help it to lay down flat. Let me know how it turns out. Regards, Nat I have a sirenge and have drilled a couple of holes. I will heat the area with a hair dryer and then clamp the hell out if it. With any luck I will be ready for my first inspection by next week... -- Ian D.S. Douglas MK0069 From: Bes1612 Date: Sat, 3 Jan 1998 09:48:07 EST Subject: COZY: Main wing spar I was able with the canard, and the bottom of the right wing spar layups to put all of the indicated plys into the spar trough. But in the top layup of the main wing I had to shorten one sooner than indicated, and just could not put one last short one in place. The plans state that these are only sugjested lengths and to put in whatever it takes to fill the trough, but I prefered to put in at least the number indicated. My guess is that there is sufficient plys there, what do you guys think? From: "norm & monda" Subject: Re: COZY: Main wing spar Date: Sat, 3 Jan 1998 10:02:52 -0500 we had the same problem, wound up being 1 ply short on the top of the wing, everyone who looked at it said it was fine. norm & monda cozy IV #202 From: "norm & monda" Subject: Re: COZY: Frustrated, Date: Sun, 1 Mar 1998 18:32:18 -0500 my plans call for a 7/16 solid rod, my friend used a 1/2" 4130 holow tube and installed lead shot so the balance could be changed after painting, by removing the end plug and adding or removing some shot, he puts steel slug dowels in to keep the shot from sliding around. norm From: cdenk@ix.netcom.com Date: Sun, 1 Mar 1998 18:25:34 -0600 (CST) Subject: Re: COZY: Frustrated- Aileron Balance Norm Doty writes Like the idea, 3 cautions: 1: Maybe the weight should be somewhat uniformally distributed along the length, and not all at one point. 2: The weight should be solidly anchored in the tube. 3: This is not to allow sloppy workmanship. AND: why not use a 7/16" tube, possibly heavy wall, and then shot for fine tuning. I start to get concerned when the external shape starts to deviate from the drawings, not being an aerodynamic person. Date: Mon, 30 Mar 1998 11:02:39 +0200 From: Rego Burger Subject: COZY: WING ATTACHMENTS Hi all, I was doing one of my pre-prep periodic inspections and noticed the wing attachments where the bolts go through the wing are exposed bare 2024..... my thoughts are, "now what do I do to prevent corrosion". Can I just paint the bare bits with some chromate prior to painting...? Rego Burger, web site: http://home.intekom.com/glen/rnb.htm (home e-mail) mailto:rnb@intekom.co.za RSA From: Bes1612 Date: Mon, 13 Apr 1998 22:10:40 EDT Subject: COZY: Ailerons; Hello everyone: I'm not happy with the peel-ply strip, placed under the skin of the wing, for the glass-to-glass bond on the ailerons. I've had a devil of a time getting all of it out of there. It lookes to me, if there was only foam and micro, you could just grind all that off, sand it good, and your in business. A little micro would be much better than peel- ply, if you happen to miss some. You have to be sure to get all of the peel-ply out, and its hard to tell sometimes. I've gone through the skin a couple of times makeing sure. I'm almost done with one, but if anyone has any sugjestions for the next one, I would appriciate it. But if I was doing it over, I would not use the peel- ply. Bob Smith From: Marc J. Zeitlin Subject: COZY: Ailerons Date: Tue, 14 Apr 98 8:40:16 EDT Bob Smith writes: >I'm not happy with the peel-ply strip, placed under the skin of the wing, for >the glass-to-glass bond on the ailerons. I've had a devil of a time getting >all of it out of there. It lookes to me, if there was only foam and micro, you >could just grind all that off, sand it good, and your in business. A little >micro would be much better than peel- ply, if you happen to miss some. Personally, I didn't have any problems removing the peel ply. I used the 1" roll that Wicks or ACS sells, which is pretty thick and holds together well. I think that while it is certainly possible to grind foam and micro off, you've got the possibility of grinding away some glass too. With the PP, you don't have to sand anything, and you guarantee that you've got the full thickness of glass for the Glass to Glass bond on the Trailing Edge. You're right that the edge of the peel ply does not always come away cleanly - it leaves some threads sometimes, but this isn't a problem - it's right next to the foam, and you still end up with the full GG bond width (at least I did). I'd be very cautious about changing to a technique that could cause a strength problem - I'd just make sure to use the coarse peel-ply. My $0.02. -- Marc J. Zeitlin Email: marcz@an.hp.com From: Epplin John A Subject: RE: COZY: Ailerons Date: Tue, 14 Apr 1998 08:02:05 -0500 I am going to add my .02 to this also. I used the same thing that Marc did. On one side I made a mistake and placed the tape in the wrong place, on the wrong side of the line. When I discovered this I had to grind off the micro and pieces of foam to get things back where they belonged. It was MUCH easier to remove the tape than to grind the micro etc. away. Take my word for it! I also had to remove the tape and replace the foam under it. What a day. John e. Mk4 #467 70% done, 95% to go. From: cdenk@ix.netcom.com Date: Tue, 14 Apr 1998 16:17:49 -0500 (CDT) Subject: Re: COZY: Ailerons Marc writes My $0.02 DITTO From: Bes1612 Date: Wed, 15 Apr 1998 17:18:24 EDT Subject: COZY: ailerons: Maybe I did something wrong in putting my PP on the foam. I understand the need for the glass to glass bond. And I used the roll of PP from ASS. But it is not coming off like it did on the wing TE, or the canard. It did set for about two months befor I cut the aileron out, if that has anything to do with it. But I am microing the tape into place. This process worked well in the other places. (wing and canard) But here on the aileron it will not come off clean. It comes off in little pieces, and has to be scraped and ground off for the most part. Evidently I'm alone in this problem so it must be my technique. I'm working through the problem, I only bring it up again hoping to find the reason. Bob Smith From: Marc J. Zeitlin Subject: COZY: ailerons: Date: Wed, 15 Apr 98 17:33:56 EDT Bob Smith wrote: >.......... It did set for >about two months befor I cut the aileron out, if that has anything to do with >it. It definitely could - the longer the peel ply stays on the layup, the harder it is to get it off. Try not to wait that long on the second one - maybe a couple of weeks? >... But I am microing the tape into place. I'm not sure what you mean here. There shouldn't be any micro between the PP and the glass skin layup. There can be micro between the PP and the foam, but that'll be removed anyway, so it's immaterial. If there's micro between the PP and the foam, and the PP gets impregnated with micro (rather than pure epoxy), that could also make it harder to peel off. It would also mean that you'd have to sand the micro off to get the Glass/Glass bond later on, negating the utility of putting the PP on in the first place. Hope this helps. -- Marc J. Zeitlin Email: marcz@an.hp.com From: cdenk@ix.netcom.com Date: Wed, 15 Apr 1998 20:16:40 -0500 (CDT) Subject: Re: COZY: ailerons: Bob Smith wrote Usually peal ply will remove easier when the epoxy is fully cured. If it is partially cured, instead od a brittle fracture of the bond, its a gummy elastic failure. The cured many times can be easily removed after getting it started with a sharp (exacto #2 blade) pointed knife, gentlly nibbling ot get a loose end even if starting not a a end, but getting a little (1/8" long) lifted with the knife, then turning the sharp edge up, cutting the peal ply a little, getting another bite, etc. until you can grip with pliers. Date: Thu, 16 Apr 1998 12:09:34 -0500 Subject: Re: COZY: ailerons: From: mikefly@juno.com (Michael B Bowden) On Wed, 15 Apr 1998 17:18:24 EDT Bes1612 writes: >Maybe I did something wrong in putting my PP on the foam. I >understand the >need for the glass to glass bond. And I used the roll of PP from ASS. >But it >is not coming off like it did on the wing TE, or the canard. It did >set for >about two months before I cut the aileron out, if that has anything to >do with >it. But I am microing the tape into place. This process worked well >in the >other places. (wing and canard) But here on the aileron it will not >come off >clean. It comes off in little pieces, and has to be scraped and >ground off >for the most part. > >Evidently I'm alone in this problem so it must be my technique. I'm >working >through the problem, I only bring it up again hoping to find the >reason. > > >Bob Smith > The peel ply in the aileron trough was more difficult than other areas for me to. I was able to remove it by grabing an end with needle nose pliers and rolling the peel ply slowly around the jaws. Sort of like opening an old style sardine can. Mike _____________________________________________________________________ You don't need to buy Internet access to use free Internet e-mail. Get completely free e-mail from Juno at http://www.juno.com Or call Juno at (800) 654-JUNO [654-5866] From: Guy TERREN Subject: COZY: Foam around LW6 Date: Thu, 30 Apr 1998 09:24:59 +0100 Hi all, When carving foam aroud LWA6 before glassing the inboard layup of the = wongs, I can't understand the different schemes: Do we have to remove the foam on the three sides of LWA6 and make a = glass to glass layup , or let the foam rounded on the lower side and the = foam flush with the wing side of LWA6 ? thanks for your answer From: Marc J. Zeitlin Subject: COZY: Foam around LW6 Date: Mon, 4 May 98 15:28:26 EDT Guy Terren wrote: >Do we have to remove the foam on the three sides of LWA6 and make a >glass to glass layup , or let the foam rounded on the lower side and the >foam flush with the wing side of LWA6 ? Surprisingly I have not seen an answer to Guy's question in the past 5 days. Here's how I read it: The plans say (Ch. 19, pg.8 MKIV): "The foam is also completely removed at the LWA6 (1/4" thick aluminum) block." I did this, surrounded the block with flox as a transition, and glassed over that to get glass/glass bonding around the LWA6. Hope this helps. -- Marc J. Zeitlin Email: marcz@an.hp.com From: "Marc J. Zeitlin" Subject: COZY: Wing/Spar attachment Date: Thu, 28 May 98 10:36:38 EDT People; So, after getting the spar on, I made the LWA9 bushings myself, not wanting to give Brock the money. Takes my about 20 minutes per bushing on a Hardinge lathe, so it's a good thing I'm not paying myself here :-). Anyway, I dry fitted the bushings to the right wing and right side of the spar, and then cut them to length for each appropriate hole. I then supported the wing on my table behind the spar with all of the bushings inserted, and bolts in the wing bushings. I shimmed it to be level and even with the spar holes, and then slowly worked it forward. Every once in a while the fates smile on me, and the bolts slid smoothly into all three holes in the spar without any banging or forcing on my part - bingo! Now, getting the washers and nuts on seems to be a major nightmare here, or else I'm just not glomming onto the technique - if anyone has any good ideas for dealing with these bolts and nuts, I'd love to hear it. I'm thinking of machining up some sort of nutplate equivalent to hold these monster nuts in place inside the spar (actually, the plans don't say whether the bolts should go in the spar or the wing - is there a preferred location? I found that my wing is somewhere between 1/10 degree and 2/10 degree off level from the spar/fuselage. I'd taken the canard off before mounting the wing, so I don't know how those two compare, but I might need to use one VERY thin washer between the lower bushings to shim the wing to dead nuts level if the wing and canard don't match up exactly level (assuming I can measure to that accuracy). On to the strakes...... -- Marc J. Zeitlin Email: marcz@an.hp.com Date: Thu, 28 May 1998 21:19:58 +0200 From: blecoq Subject: Re: COZY: Wing/Spar attachment Marc J. Zeitlin wrote: > Now, getting the washers and nuts on seems to be a major > nightmare here, or else I'm just not glomming onto the technique - if > anyone has any good ideas for dealing with these bolts and nuts, I'd > love to hear it. I'm thinking of machining up some sort of nutplate > equivalent to hold these monster nuts in place inside the spar > (actually, the plans don't say whether the bolts should go in the spar > or the wing - is there a preferred location? > Mark , I had the same problem at the beginning, and after a while you will get used to it. First of all, If you look at the pictures in the wing chapter, it shows that bolts should be in the spar. I indeed bolted and unbolted both wings on the spar numerous times during the final contouring. (Sanding of the strakes and wings was done wings bolted but the applying of the micro was done wings off to avoid glueing them on). So I got pretty quick after some time.The washer is put by sliding it on a light metal rule , then I move the ruler inside the bolt hole in the wing barely touching the bolt that was already inserted from the other side. Then with a small screwdriver I push the washer along the ruler and then up around the bolt.You have to find out the ruler that works the best and make sure you keep it ( No kid picking it up). Then comes the trickiest: putting the bolt on. The easiest way I found was to slightly screw it on the tip of my longest finger .The diameter is such that it gets on a little bit. ( Don't hurt yourself by using a wrench, just hand turning it works ).Then you insert the finger with the bolt on top inside the hole , push it on the bolt and do a slight turning movement clockwise. After an education time you should be able to get it on slightly. ( I am now quite quick). You then insert the wrench extension with the proper diameter insert at the end being cautious not to turn counter clockwise and turn by hand the extension up to a point where the wrench is needed. This is a point where the bolt will not get out so you are set. Hope this helps. Happy building. > I found that my wing is somewhere between 1/10 degree and 2/10 degree > off level from the spar/fuselage. I'd taken the canard off before > mounting the wing, so I don't know how those two compare, but I might > need to use one VERY thin washer between the lower bushings to shim the > wing to dead nuts level if the wing and canard don't match up exactly > level (assuming I can measure to that accuracy). When I did the very final angle of attack setting of the wings before contouring.( after the strakes were done because before I found that the spar was a bit light torsionwise ) I found that I had to lightly sand a washer to be exactly set.This took me several days because each time you unbolt the wing you detune the fuselage levelness.So when you check , you have to level everything out. And I had made the decision that to do that final check, both wings should be on. It usually took me 2 hours to shim everything back again level and be able to check the wing angle of attack. Happy building Benoit LECOQ From: "Marc J. Zeitlin" Subject: Re: COZY: Wing/Spar attachment Date: Thu, 28 May 98 15:46:17 EDT Benoit Lecoq wrote; >First of all, If you look at the pictures in the wing chapter, it shows that >bolts should be in the spar. Hmmm. Since you pointed that out, I found the pictures on page 19-12 and 19-13 which show the bolts in the wing and the nuts in the spar. I wonder if it makes any difference at all, except for the ease of assembly - I wouldn't think it would. >Hope this helps. Happy building. Thanks for the technique - if I don't end up making my "nutplate" idea, I'll probably use this, as it clearly works. If I do figure out some sort of "nutplate" idea, I'll let everyone know..... -- Marc J. Zeitlin Email: marcz@an.hp.com Date: Fri, 29 May 1998 11:00:17 +0200 From: blecoq Subject: Re: COZY: Wing/Spar attachment > Benoit Lecoq wrote; > > >First of all, If you look at the pictures in the wing chapter, it shows that > >bolts should be in the spar. > > Hmmm. Since you pointed that out, I found the pictures on page 19-12 > and 19-13 which show the bolts in the wing and the nuts in the spar. I > wonder if it makes any difference at all, except for the ease of > assembly - I wouldn't think it would. > Oooops, I goofed there!!! The double check on my plans showed up the mistake. Well, kind of agree with you that it does not make any difference. May be Nat has an idea on that. I just hope I did not make more mistake when reading the plans. Obviously this one is easy to correct. This is a good wake up call as we could say. The one you need when you start to be too confident because it has no impact. Yours sincerely. Benoit LECOQ Date: Fri, 29 May 1998 05:18:40 -0400 From: Eddie VANN <100740.3723@compuserve.com> Subject: COZY: Copie de : Wing Bolts ---------- Message r=E9achemin=E9---------- De : Eddie VANN, 100740,3723 A : Cozy Forum, INTERNET:cozy_builders@hpwarhw.an.hp.com DATE : 29/05/98 07:51 RE : Copie de : Wing Bolts I simplify this task by gluing the washers on to the nuts with a dab of superglue. Then I use a socket extension which brings the nut onto the bolt with the proper alignment and my helper turns the bolt. Mounting the wings, which seemed so formidable the first time, now takes less than 30 mins. Eddie Vann Long-Ez F-PGEV Date: Fri, 29 May 1998 13:11:03 +0200 From: Rego Burger Subject: COZY: Wing/Spar attachment Few things. Use plain nuts for temp. fitting of wing..makes screw on by hand easy, get young kid with small hands to hold head or nut in place through spar...my son enjoys it. Remember to use castle or grip nuts on FINAL assembly. Tools: Match socket extensions for easy grip. I don't think the direction of the bolts make much difference. If the nuts come off the wing comes off anyway. My idea is to make a hex "stamped" plate to hold bolts in place when finsihed, this will allow me to "slip" the wing onto the three bolts pointing out at me. It's then a case of fitting the nuts and washers. The plate can be bolted with an AN3 bolt like the aileron belcrank plates... there is enough clearance between the wing gaps. If anyone has some technical reasons why the bolts can only go in one way please share them with us. Rego Burger, web site: http://home.intekom.com/glen/rnb.htm (home e-mail) mailto:rnb@intekom.co.za RSA From: cdenk@ix.netcom.com Date: Fri, 29 May 1998 08:15:36 -0500 (CDT) Subject: Re: COZY: Wing/Spar attachment Rego writes I prefer the bolts inserted into the center spar, pointed aft. I use a couple of long forceps clipped onto the protruding bolts (on top the washers (all mine are one thin washer) to keep the bolts from slipping inward as the wing is slipped on. For the bolt head, I use a 1/2" drive ratchet with a deep socket. The length of the socket/ratchet is critical, experiment with the wing off. Just going to hold the bolt, turn the nut. For the inner bolts I use a box or open end wrench. For the nut, I use a 3/8" socket, short extension, u-joint, long extension. Remember to provide a drain hole for the top nut access area. Date: Fri, 29 May 1998 06:09:44 -0500 From: Wayne Walter Peterson Subject: COZY: Aileron travel I was wondering what the aileron travel in degrees is as measured off the outboard wing at just outboard to the aileron? The Long-EZ plans look as if 70 total,35 up, 35 down. Any idea? Wayne Peterson,a Berkut builder. Date: Sat, 30 May 1998 22:29:06 -0400 From: Ian Douglas Subject: COZY: Wings - Peel Ply and Floxed Corners Just a quick question. Can I replace the peel ply that is placed for the ailerons and along the trailing edge with duct tape? It seems to me that it would be easier to remove duct tape than peel ply from those positions. Anyone try this? The plans state that flox corners are required (section B-B) at the wing attach hard points. When I made mine I radiused the corners and it has turned out that the spar caps ended up flush with the tops of the hard points. Since I already have a radiused corner there is no place to add flox. Can I just skip the flox or do I have to mill the LWs? Seems to me that I should be able to ignore the flox. -- Best regards, Ian D.S. Douglas Director of Technology Workplace Technologies Corporation If you write software, send me your resume! Date: Thu, 28 May 1998 23:14:23 -0700 From: "LCDR James D. Newman" Subject: Re: Wing/Spar attachment Hi Marc, > Now, getting the washers and nuts on seems to be a major nightmare here, or else I'm just not glomming onto the technique - if anyone has any good ideas for dealing with these bolts and nuts, I'd love to hear it. Put a drop of Super Glue or Lock Tite to hold the washers in place on the bushings. Also - very important - mark which washers go where on the wing (and in the aircraft log book and/or owners manual) so that the next time you take the wings off you won't forget where they go. Have marked spare washers along in the plane too. > I'm thinking of machining up some sort of nut plate equivalent to hold these monster nuts in place inside the spar (actually, the plans don't say whether the bolts should go in the spar or the wing - is there a preferred location? The plans do show the nuts going into the center section spar with the wing bolts through the wing first (page 19-12 of the Long-EZ Wing and Aileron Chapter). It actually doesn't matter which way the bolts go, but the reason Rutan put them in through the wing is because most builders do not get the wing bolt holes near perfectly parallel to each other and/or horizontal and/or the bolt holes are tweaked from side to side. If the wing bolts are sticking out the back of the center section spar and any of the previous is the situation, the builder can not get the wings on or off. But if he gets the wing bolt holes near perfectly parallel to each other, horizontal and not tweaked, it is a great pleasure and easier to put/get the wings on and off. One could do it by himself with a frame the wings set on to just slide the wings onto the protruding bolts. Sticking the wing bolts through the wing is easy with 1 preferably 2 people helping you. But if the wing bolts stick out the back of the center section spar, you would need to have a way to hold the bolt head inside the center section spar. Capping off a box wrench would work, but you would still need the access hole in the bottom of the center section spar [ :-( ]. I like and must have the wing bolts sticking out the back of the center section spar for the wing bolts hold the back support plate for my main retracts (unless one installs an extra set of AN-3 bolts through the back support plate to hold the gear). And as I said above, I have a machined means to hold the bolt heads to act as a wrench so I don't need a access hole in the bottom of the center section spar just to slide a wrench onto the bolt heads. HTH. Infinity's Forever, JD Date: Mon, 1 Jun 1998 22:13:46 -0400 From: Bill Theeringer Subject: COZY: Solo wing attach? After reading the posts about wing attach bolts and how the best way might be to attach the wings it dawned on me that I might just be the only person who regularly removes and installs Long EZ wings by themselves. I didn't give it much thought because I thought everybody did this! I will share with you what I have done hoping that It might make some one elses job a little easier. The wing attach bolts all have specific lengths (dash numbers) for their respective locations. Write the lengths and shim washer requirements on the forward face of the spar with a magic marker, where it will never be lost. Bolt lengths are (of course) determined after washer requirements are established. Two threads sticking out of the bolt when tight defined the lengths. The bolts are AN916-XXXA and the washers are AN960-816, or AN960-816L for the thin ones. The bolts are inserted into the CS spar. Three spring loaded devices were made up to provide a constant pressure on each of the 3 bolts. These devices are made from 2 pieces of 6061-T6 .065 wall pipe, two sizes. One just fits inside the other and each has a blind end plug similar to the torque tube on the old Long EZ elevator. Insert a suitable diameter stiff spring inside the assembly and put a rubber crutch tip on each end. You now have a compressible stubby pipe with crutch tips on each end. Make three and put them inside the spar between the bolt heads and the forward face of the inside of the spar box. Install the required spacer washer shims and install the wing. The bolts will tend to align themselves and as you push the wing in place the bolts will force themselves into the wing fittings and will "pop" into place. To do this solo I have a 5 foot step ladder with a wedged shaped piece of blue foam stuck to the top caped off with non skid rubber. After much experience the ladder is placed just so with the end of the wing on top. The inboard bolt is started first with the other two being compressed by the springs. With the inboard bolt in the wing, the outboard end is lifted or lowered slightly until the other two pop into alignment. Bill Theeringer N29EZ See our award winning Long EZ with Jim Newmans excellent retractable gear at http://www.flash.net/~infaero/infgear.htm Composite Aircraft Accessories HOME: 805-964-5454, SHOP: 805-964-5453 E Mail: Composite_Aircraft_Accessories@Compuserve.com PO Box 21645 Santa Barbara, CA 93121 Date: Tue, 23 Jun 1998 09:53:22 -0700 Subject: Re: COZY: comparing canard to main wing incidence From: alwick@juno.com (ok How) On Mon, 22 Jun 1998 09:38:06 -0500 "Nat Puffer" writes: SNIP >of the light wing. Either will level the wings, but then the question is, >how is the resulting incidence compared with the canard incidence. The only >way to determine that would be to level the airplane and then check the >incidence of both the canard and the main wings. If the main wings have too >much incidence in relationship to the canard, that will reduce the stall margin. >In our flight tests, after adding lower winglets and shortening the canard >span, we checked for stall resistance in level flight at idle power, slowly SNIP I could use some advice here. What is the best way to define the main wing incidence? I know, level longerons, place latest template on canard, measure angle with precision level. But when you do the wings, what is the datum? Top of strakes? Bottom of strakes? Or do you use tool to find center of leading edge, center of trailing edge and define that as the level of the wings. RC guys use this center finding tool. I guess what I'm trying to say is that I want to make sure that when I measure the main wing incidence, that I'm not measuring some slight builder variation and arriving at wrong conclusion. Maybe the answer is measure all of the above. But I need something to compare it to. I already knocked off the board secured to main wing. But it was dead on when I checked it months and months ago. I've put one of my RC planes in flat spin before, and couldn't get out of it. Sorta paranoid about that. Thanks -al _____________________________________________________________________ You don't need to buy Internet access to use free Internet e-mail. Get completely free e-mail from Juno at http://www.juno.com Or call Juno at (800) 654-JUNO [654-5866] From: "Nat Puffer" Subject: Re: COZY: comparing canard to main wing incidence Date: Tue, 23 Jun 1998 11:37:43 -0500 Dear Al, You raise a very good question. If a Cozy requires a lot of roll trim, it might require an investigation to determine the cause. Rego Burger suggested that one wing might be heavier in weight than the other, which would require roll trim. That is probably true. Also, the elevators in the canard might not be exactly in-line. This could also cause a roll problem. If the canard span on one side wasn't the same as on the other (don't laugh, I know of one case where this was true), it could also cause a roll problem. Maybe, in a first flight, with just the pilot on one side and fuel in the tank on the same side as the pilot, you would need more roll trim than with a passenger and fuel in both tanks, etc. I seldom have to adjust roll trim for fuel burn, but I notice that my Navaid is sensitive to weight on one side or the other of the fuselage. But getting back to wing incidence, I have used the procedure recommended in the plans on 3 different Cozys, and did not encounter any problems, nor have most other builders. This procedure, without reviewing it in detail, is considered much superior to the procedure in the Long EZ plans, where you first mount the center spar in the fuselage, and then build a frame for both wings to jig bore the wings to the centerspar after it is in the airplane. If the procedure in the plans is followed carefully, both wings should be at the correct incidence automatically. I know of one case where a custom shop built a Cozy very sloppily for Dick Smith, and it had to be completed and then rebuilt by Ken Francis. It flew very badly. Apparently the custom shop did not follow the procedure in the plans and both wings were badly at the wrong incidence. If I remember, one wing had to be changed about 1/4 in. at the leading edge, compared to the strake, and the other about 3/8 in. This required a lot of washers, and wasn't a good fix. I believe the way Ken finally determined what the problem was, was to use the jigs shown in the plans to hold the wings level while glassing them and while installing the level boards prior to mating them with the centerspar. Use of these jigs is the logical way to check wing incidence, and the only way I know of. The longerons would obviously have to be level, and the jigs would have to be used at the correct butt line. I have never had to check wing incidence in a completed airplane, but Ken Francis and Vance Atkinson (they hangar together) have used this procedure. Again, if you carefully follow the procedure in the plans, it shouldn't be necessary. And if Dave only had to install one (or two) thin washers, it probably isn't a big deal. It is a valid point, however, that for the airplane to perform the same as the one we tested, both the wings and the canard have to be at the correct incidence, and if you follow the plans, you shouldn't have to worry. Hope this helps. Nat Date: Tue, 23 Jun 1998 16:25:21 -0400 From: David Domeier Subject: Re: COZY: comparing canard to main wing incidence Nat, re "Rego Burger suggested that one wing might be heavier in weight than the other, which would require roll trim." Or it might be longer. Truth is my left wing tip comes in a BL 169 and the right wing is at BL 169.5. Both are at FS 156. That would produce more lift on the right side. When I had my LEZ certified by the FAA in 1983, I sort of apologized to the inspector 'cause some of my measurements were off a bit. He replied, "Don't sweat it, I've seen Cessna's off by more than an inch". My LEZ flew straight from day one. The incidence was OK without adjustment. On this airplane it could be the elevators not true to each other and also, I need to tweek the left rudder a bit. It needs some right rudder to center the ball, but it is fared. The left rudder is out just a bit and needs it's stop filed down. Other than that I think a straight airplane on the first flight may be a bit of luck . I had to drill my wing attach holes with each wing in place seperately, since my garage was not big enough to do it otherwise. A different position on the garage floor might have made a difference. This business isn't perfect but the machines fly great anyhow. dd From: "Wilhelmson, Jack" Subject: RE: COZY: comparing canard to main wing incidence Date: Tue, 23 Jun 1998 17:12:18 -0400 Al: After it's all said and done the relative incidence between the wing and the canard is what is most important. This is easy to check once the airplane is flying and before you let the airplane out of it's test CG box. The elevator postion at cruise should be as shown on the plans. If it is down the canard incidence is probably to low. Right NAT? This is a good reason not to do the final finishing until after the first few test flights. Jack Wilhelmson N711CZ From: cdenk@ix.netcom.com Date: Tue, 23 Jun 1998 18:05:19 -0500 (CDT) Subject: Re: COZY: comparing canard to main wing incidence Al Wick writes I used a female top (made from the hot wire template) template to determine the water line of the leading edge. The trailing edge is a sharp edge, with the elevator in line top and bottom. Now that you know where the waterline references are, refer to the plan (top) view of the wing in the book, where the waterline elevations are noted. I used a water level (plastic tube) and ruler to check. Probably an engineer's (optical) level would be better, but if you don't know how to peg test one, I would question it. It may take only a small bump to put one out of adjustment. Just because the level will stay put, doesn't attest to its accuracy. I went around and around for several nights, using mixing sticks for shims on solid supports, a little change here caused a change there. When everything looked a good as it was going to be, I buit the strake. I even did this with the airframe upside down in the garage with the engine and wings mounted. From: "Marc J. Zeitlin" Subject: COZY: Incidence Date: Wed, 24 Jun 98 10:58:27 EDT Nat Puffer wrote (but for some reason that I hope Wayne Wright can help me fix, the message didn't get through): >All, >Jack Wilhelmson (one of the first to fly a Cozy) is correct. It is the >relationship between the wing and canard incidences that is important. If >the relationship is correct, at mid to aft c.g. and fast cruise, the >elevator trailing edge should be between neutral and trailing edge up about >2 degrees. The tip off that Nick Ugolini had a canard incidence problem on >the Long EZ he purchased was that in cruise, the elevator trailing edge was >down several degrees. The other tip off was that it was unstable in pitch, >that is, if he pulled back a little on the stick, he said it would climb >"like a banshee". I recall that after Pat Young's deep stall accident he >told me that he noticed the same characteristics with his airplane. >According to our data, his elevator position did not agree with where he >said his c.g. was, indicating that either his canard incidence was too low, >or his c.g. was too far aft. In newsletter 56, page 5, we re-published our >test data on elevator position as a function of c.g. and speed. Use this to >double-check your c.g. calculations and incidences before you test the aft >portion of the flight envelope in slow flight. For normal solo operation we >suggest you ballast so you are ahead of the aft c.g. If you have any >questions, please contact me. >Regards, >Nat -- Marc J. Zeitlin Email: marcz@an.hp.com Date: Tue, 30 Jun 1998 13:49:54 -0400 From: "Johnson, Phillip" Subject: Re: COZY: comparing canard to main wing incidence When I set my wings onto my spar and my spar into my fuselage, I was concerned about the wing incidence so I developed my own scheme for measuring incidence and wing twist (no wing is perfect). To do this I attached the wings to the spar (spar not yet attached to the fuselage) and set the level as best I could using the two boards as per plans. I then attached a piece of 1" wide white masking tape to the leading edge of the wing. Now with a 48" spirit level touching the floor, and the leading edge of the wing, and as vertical as possible, rub the masking tape with the level using a piece of carbon paper in between. The mark left is the leading edge of the wing. (Any errors from incorrect incidence are second order.) I did this down the full length of the wing. It is now possible to identify the leading edge since the irregularities become obvious. Now I went to the wing assembly jig templates that come with the plans, and measured the difference in height between the leading edge and the trailing edge and tabulated the results for each jig location. I also created values, by interpolation, for virtual jigs placed between the real jigs. I now marked the location of the jigs accurately on the leading and trailing edges including the virtual jigs. Now comes the measuring bit. I used a water gauge (a piece of clear plastic tubing with water and food dye in it) to measure the difference in height between the leading edge and the trailing edge and again tabulated the results. From the measured data and the jig data I was able to measure the error in the incidence angle over seven points down the wing and graph the results. I could detect a slight twist in the wing in the order of 0.1 degrees on one wing. I elected to make the outboard end of the wing within spec leaving the inboard end of the wing to be in error when assembled to the spar and shimmed. I chose to correct in this manner since the outboard end of the wing will produce the most roll effect. (we'll see on the first flight if I was right). The reason I went to all this trouble is that I did not believe that it was possible to make a perfect wing, there is always some error no matter how small, so the two boards that were bonded to the wing during assembly give a reference at one position only. I had also heard some horror stories from builders who had had their wings twist during storage between build and final assembly. This method allows the builder to quantify the quality of build/storage. I hope this description is of use to someone. ---------------------------------------------------------------------- Phillip Johnson Tel (613) 253 2229 (H) Ottawa, (613) 599 3280 ext. 232 Ontario, Cozy MKIV RG #30 Canada. Subaru EG33 ----------------------------------------------------------------------- From: lschuler@cellular.uscc.com Date: Tue, 30 Jun 98 16:41:19 -0600 Subject: Re[2]: COZY: comparing canard to main wing incidence Phillip Johnson Wrote: >snip >I had also heard some horror stories from builders who had had their >wings twist during storage between build and final assembly. This >method allows the builder to quantify the quality of build/storage. If I understood correctly, you ended up with only a 0.1 degree twist in one wing after a couple years in the rafters? If true, seems like storage may be a minor issue. I would have been more concerned about the squirles taking chunks of foam for bedding..... :-) (inside joke) >I hope this description is of use to someone. Thanks for the neat idea. Sure will be of use to me. I'll make use of it in a year or two when I get to that mounting point. Should I be thinking of adding some level boards outboard of plans version at the appropriate time during wing construction? Larry Schuler MK-IV plans #500 (working on my nose :-)) lschuler@cellular.uscc.com From: Epplin John A Subject: RE: COZY: comparing canard to main wing incidence Date: Wed, 1 Jul 1998 11:19:22 -0500 Nat Puffer writes > I have always stored my > wings and canards leading edge down, winglets supported, in special jigs > which are airfoil shaped and lined with carpet. Storing them this way > imparts the least bending or twisting stress. [Epplin John A] I totally agree with Nat. An easy way to come up with a support is to use the webbing material sold to repair lawn chairs. I made a simple cradle with bottom dollar 2X4 lumber, it rests the wing on the spar face against a scrap of foam and the tip is supported with 3 strands of the webbing spaced about 12 to 18 in apart. This gives a lot of support area and it is leading edge down. Made two of these and they stack neatly against the garage wall. I do screw them to the wall so there is no chance of them getting blown over. A lot of surface area there. I have not yet attached the winglets, elected to leave this till the end of the structure building phase. Makes it much easier to store. John epplin Mk4 #467 From: "Wilhelmson, Jack" Subject: RE: COZY: comparing canard to main wing incidence Date: Wed, 1 Jul 1998 13:00:38 -0400 Nat: I seem to remember that the Cozy wings have a built in washout twist to counteract the twisting moment of the winglet drag and the lift vector. Is this correct? Also I remeber that John Ash built one of his wings without the twist and tried to use Burt's procedure to twist it with no success. He gave up and rebuilt the wing. Jack Wilhelmson N711CZ > -----Original Message----- > From: Nat Puffer [SMTP:cozy@extremezone.com] > Sent: Wednesday, July 01, 1998 9:28 AM > To: David Domeier; Johnson, Phillip > Cc: 'Cozy Mailing List' > Subject: Re: COZY: comparing canard to main wing incidence > > David, Phillip, and All, > I have never noticed distortion of any of the components on any of the > airplanes I have built, but then I have never accurately checked for > distortion. Factors to consider, my projects have never exceeded 24 > months > from start to finish, and during construction, I have always stored my > wings and canards leading edge down, winglets supported, in special > jigs > which are airfoil shaped and lined with carpet. Storing them this way > imparts the least bending or twisting stress. I seem to remember many > years > ago Burt published something in one of the Canard Pushers, in which he > suggested a way to change the twist in a wing, but it involved > applying a > lot of twisting force (weight on the end of a beam) while cooking the > wing > at about 150 deg. F. If someone has one of the CDs, maybe he could > look > this up and see if my memory is correct. I was left with the > impression > that it was so difficult to impart a twist, that it wasn't likely to > occur > under normal circumstances. > Regards, > Nat > > ---------- > > From: David Domeier > > To: Johnson, Phillip > > Cc: 'Cozy Mailing List' > > Subject: Re: COZY: comparing canard to main wing incidence > > Date: Wednesday, July 01, 1998 6:43 AM > > > > Phil, > > > > Good post on incidence. > > > > re "I had also heard some horror stories from builders who had > had > > their wings twist during storage between build and final assembly." > > > > My rudders were stored on a shelf subject to temps over 100 > degrees > > for about 3 years and I'm sure the left one warped somewhat. It > does > > not fit the winglet as if it were cut from it and the middle hinge > line > > is off just a bit. The rudder functions OK but I am not satisfied > with > > the fit - but haven't figured out what to do about it. > > > > dd > > Date: Thu, 02 Jul 1998 08:46:35 -0400 From: "Johnson, Phillip" Subject: Re: COZY: comparing canard to main wing incidence Nat Writes: Snip> I have never noticed distortion of any of the components on any of the airplanes I have built, but then I have never accurately checked for distortion. end< The point that I am trying to make is that all wings will be imperfect. It is not possible to make the perfect wing. The question is: How close to perfect are "YOUR" wings (Nat this is not referring to your wings specifically), and what is an acceptable limit? A 0.1 degree twist in the wing is an error of 0.05 inches (1.25 mm) when the chord is 30 inches. No one is going to notice this unless they have performed measurements such as the ones that I wrote about in my last post. If the wing did have a visible twist, scrap it. ---------------------------------------------------------------------- Phillip Johnson Tel (613) 253 2229 (H) Ottawa, (613) 599 3280 ext. 232 Ontario, Cozy MKIV RG #30 Canada. Subaru EG33 ----------------------------------------------------------------------- Date: Thu, 02 Jul 1998 09:02:02 -0400 From: "Johnson, Phillip" Subject: RE: COZY: comparing canard to main wing incidence Jack Wilhelmson writes: snip> The wings are supposed to have a leading edge downward twist to compensate for the twisting moment that comes from the lift vector. Nat can give you the correct amount if you ask him. Subject: COZY: main wing airfoil listing david lednicer has announced the availability of a list of airfoils used on various aircraft. mike selig is hosting it off of his uiuc site: http://amber.aae.uiuc.edu/~m-selig/ david is asking for additions and corrections, particularly: the Douglas A-26, the Martin B-26, the original DC-3 (he has the Super DC-3), the Lockheed 049 Constellation and 2049 Starliner and the DeHavilland 88 Comet racer. he has the long-eze (found in the special canard section) as using an eppler 1230 airfoil for the main wing. i thought it was a MODIFIED eppler 1230? the modification is rumored to be that the aft of the lower surface was straightened to reduce the pitching moment with a slight penalty in drag. has anyone made the comparison of the templates to the standard 1230 to confirm or deny this? according to the cozy archives (same airfoil), no one has reported doing so. -- bil Date: Sun, 09 Aug 1998 17:49:18 -0500 From: Bulent Aliev Subject: Re: COZY: Oxydation on A13 "Hi All, A friend of mine told me that he saw a Cozy with oxydation in front of the ailerons. It is surely the A13 steel bar which corrodes. Has anyone got the same problem. Being ready to bond the rod, i would like to know if any treatment is useful to prevent the corrosion Thanks Guy" Hi Terry, I was concerned with oxidation during the whole construction of my Cozy. Here in FL it is a big problem with everything - from planes to boats. I purchased the steel roads as per plans, but could not accept the fact using raw steel in my ailerons since once steel encased in fiberglass starts rusting, you can not stop it. It will even brake out and deform the fiberglass. I went to Home Depot and purchased the same size steel rod but galvanized. BTW I was looking at the original (per plans) rods yesterday and they are real rusty mess already. My brakes are the marine version 3 puck from Matco with SS disks and hardware. Regards Bulent in FL Date: Thu, 13 Aug 1998 08:03:56 +0200 From: Rego Burger Subject: COZY: Oxydation on A13 This same fear of rust lead me to modify mine at my own risk...... I installed a brass tube in place of the steel rods . The idea was to get away from rust prone materials...( I live by the sea.) To balance the ailerons I made a LEAD mould to cast 2" long slugs that slip into the tube. All I must do now is make sure the lead slugs will not come out... some form of split pin at the ends for safety , but they will be bonded in the tube to prevent vibration problems. Rego Burger, web site: http://home.intekom.com/glen/rnb.htm (home e-mail) mailto:rnb@intekom.co.za RSA From: "terren" Subject: COZY: Covering the end of A13 Date: Sat, 15 Aug 1998 19:28:53 +0200 Hi, All Still my problems covering A13. but now the ends of A13. A13 is full span, so i think very difficult to cover extremities of A13 while waking the ribs layup #11 after recessing the foam. My question: during what layup #10 or 11 do we do it ?. Do we nned to cut A13 to 65" less 0.8" ? Thanks for an answer today, i'll try layup#10 tomorrow. Guy From: wkasty@ix.netcom.com Date: Mon, 17 Aug 1998 16:43:58 -0500 (CDT) Subject: Re: COZY: Covering the end of A13 On 08/15/98 19:28:53 you wrote: > >Hi, All >Still my problems covering A13. but now the ends of A13. >A13 is full span, so i think very difficult to cover extremities of A13 >while waking the ribs layup #11 after recessing the foam. >My question: during what layup #10 or 11 do we do it ?. Do we nned to cut >A13 to 65" less 0.8" ? > >Thanks for an answer today, i'll try layup#10 tomorrow. > >Guy > > > > Guy, I just finished my first wing. I simply roughed up the end of A13 and then applied a small amount of micro to cover it up. This can be sanded smooth and if needed, the wing can be trimmed down to match closely. Bill Kastenholz Cozy MKIV#536 wkasty@ix.netcom.com Date: Tue, 18 Aug 1998 10:22:18 -0400 From: Neil Clayton Subject: COZY: Re: Wing Bolt holes; Dull Spotfacing Thanks to everone who replied on this. I thought of a way to avoid having to drill the Alum plates (MG1&2) with the spotfacing tool. I machined out the plates to their final diameter (5/8") then made up push-fit insert disks 5/8" dia, with a central reamed 1/4" hole. I'll use the 1/4" holes to align the plates, bolt them onto the bulkhead, then punch out the inserts leaving the 5/8" holes, then use a standard hole saw to open up the bulkhead to 5/8". Might work? Neil At 07:46 AM 8/18/98 -0400, you wrote: >[The Canard Aviators's Mailing list] > Subj: Re: Wing Bolt holes; Dull Spotfacing Tool > Author: sschlam@HME.com > Date: 8/17/98 > >It sounds like this would be a good suggestion in a machine shop type of >operation where you are just cutting on the Aluminum. However for the >wing bolt holes I would think the wax would contaminate the hole >preventing (or at least detracting from) good integrity of the epoxy >bond to the bushing. I will be cutting the holes for wing attach >fittings on a Long EZ in the next week or so. > >I plan to sharpen the tool as necessary, alternate drilling between >holes rather than drill through in one shot (so they have time to cool), >and if I get brave, use water to cool the hole. > >Subject: [canard-aviators] Re: Wing Bolt holes; Dull Spotfacing Tool >Author: SE:tbartley@waterchem.com at INTERNET >Date: 8/16/98 8:33 AM > > >Lubricate your spotfacing tool with beeswax when drilling aluminum. You >will find that the tool will continue to work well. The beeswax melts >as the metal heats up. > >Terry Bartley > > >---------------------------------------------------------------------- >For details on sponsors of this list, copyrights, and how to remove >yourself from this list, please visit: > >http://www.canard.com/ca-ending.html > >(c) 1997,1998 Canard Aviators. support@canard.com >---------------------------------------------------------------------- > > Date: Tue, 18 Aug 1998 18:13:30 -0500 From: "DONALD E. HENRY" Subject: COZY: Re: [canard-aviators] Re: Wing Bolt holes; Dull Spotfacing Neil Clayton wrote: > [The Canard Aviators's Mailing list] > Thanks to everone who replied on this. I thought of a way to avoid > having to drill the Alum plates (MG1&2) with the spotfacing tool. > Hi all, I had the same problem as everyone else using a spot face. I bought an eight inch long 5/8" drill, had local machine shop grind down the cutting end back about 3/8" to produce a 1/4" pilot, then regrind the cutting edge to 12 degrees (less aggressive bite) its still aggressive if you put a lot of pressure behind it. I drilled all 6 holes without having to resharpen and it produces very little heat and is a lot cheaper than a spot face. From: cdenk@ix.netcom.com Date: Mon, 14 Sep 1998 19:45:41 -0500 (CDT) Subject: COZY: Wing shims hrogers writes If the wing is attached to the spar and properly aligned when installing the strake tops and bottoms and with 1 thin washer at each bolt, this will be your final alignment. The spar is flexible in torsion until the strakes are complete. From: cdenk@ix.netcom.com Date: Sun, 27 Sep 1998 11:01:54 -0500 (CDT) Subject: COZY: Control Bearings Here are the bearings I used in my COSY CLASSIC, with comments: Wing Aileron: Spherco COR-10, 5/8" Bore Stainless Steel Spherical ball bearing. Mounted in the CS-150 phenolic bearing material by boring the hole to fit, then laid up 2 plys BID on both sides as a retainer for the spherical bearing. Then installed CS-150 per instructions. Changed CS-152 5/8" tube to stainless steel, anticipating possibility of corrosion of steel, since there is some axial (lengthwise) movement and occasionally removing aileron. Firewall: Spherco COR-10, 5/8" Bore Stainless Steel Spherical ball bearing. The bearings are floxed directly into the firewall, with aluminum retainers front and rear. The forward retainer has 2 nut plates and is floxed and 2 plies BID to hold in place if necessary to remove. Machine screws go through aft retainer and anchor in nut plates. All spherical bearings get a squirt of silicone spray at annual to flush dirt out and lubricate. Fuselage at F.S. 80: Bunting Rulon PTFE #DRF101406, 5/8" I.D. x 7/8" O.D. x 3/4" O.A.L., Flange 1/8" thick x 1" O.D. plastic sleeve bearings. Floxed into CS-117 1/4" phenolic bearing retainers, roughened O.D. of bearings first with Dremel cutter. Had to go back at later date and clean out bearing I.D. due to minor misalignment. Changed CS-115 5/8" tube to stainless steel, anticipating possibility of corrosion of steel, since there is some axial (lengthwise) movement. Hindsight, might use the COR-10 or ball bearings here also. Fuselage at Control Stick: Used 5/8" bore ball bearings (my records are missing a part number). They should have seals both sides and be self-aligning to about +/- 2 degrees. If I remember, they had a snapring like shoulder that allowed floxing to the CS-109, with a one sided aluminum retainer with 2 machine screws. As a result of low friction, I was able to change the aileron trim springs to ones with approximately ½ the force, and much lighter side stick force. Then the autopilot servo slip clutch can also be set to a lowere force, allowing easy overide for brief periods. From: cdenk@ix.netcom.com Date: Thu, 19 Nov 1998 07:47:38 -0600 (CST) Subject: Re: COZY: Melted Wing (Chp 19) On 11/19/98 03:16:00 you wrote: > > >Advice needed to rectify a self induced problem. >Just about to finish my second wing and do the wing rib lay ups when I let my >gas heater get too close to part of the wing. Needless to say it got too hot >and melted some of the foam underneath. It has also made the skin bulge in >places. >The area is about 12inx12in directly behind the main spar, top surface, and >11in from the inboard attatch bolt. Main spar and shear web not affected. >Anyone else had to do this kind of repair? >Should I cut the affected area, repair the foam, re-contour and re-cover with >same number of plies and orientation overlaping etc . (How much) What extra >layers (UNI spanwise maybe?) should I put over the patch if any? > >Thanks for your help > >Richard Goodwin (England) > > I would do the following: 1: Cut a neat hole in the existing foam. 2: Cut a new block of foam to fit snug, so it will slide in without binding, and excessive clearance. Don't try to match top surface at this time, just that there is more than enough. 3: punch many little (1/8" or less) (say 3 or 4" spacing) vent holes through the blind side, to allow trapped air to escape. 4: Butter all mating surfaces with micro, a little thicker than slurry, but not anywhere near dry. You want it to flow slightly to fill irregularities under light pressure. 5: Install the block, and weight down. 6: along the visible foam block edges, inject with a syringe micro slurry to fill any voids. There should not be many or other than small voids if you have done everything correctly. 7: Contour the top surface 8: Repair the fiberglass, see the chapter that describes repairs. It says something like same layups, 1" lap per ply, plus 1 ply BID over the repair. I would do the extra ply BID only 1" beyond the repair lap on top, and 1" beyond the existing ply underneath. Would look at recessing foam to accommodate this added thickness of 1 ply BID. From: cdenk@ix.netcom.com Date: Fri, 20 Nov 1998 17:53:35 -0600 (CST) Subject: Re: COZY: aeleron controls in wing (chap 19) On 11/20/98 10:37:40 you wrote: > >Firstly thanks very much for all the advice on my melted wing. Repair under >way and looking good so far. > >I am in the process of fitting the welded belhorn (CS152R) from brock. With a >standard AN 3 bolt through the end ( short end in the wing root) there is too >much play in the concentric shafts. I measured the hole and informed Brock. >They admitted that the hole was .004 in oversize and sugested a close >tolerence bolt or send them back. (not so easy from UK) I was thinking of >using some tapper pins and have read (somewere) about others using them in the >past. Which are the best part Nos. to order from ACS for the control system? >Thanks for your help. > >Richard Goodwin > > Could you drill it out to a metric size, that would be just slightly larger. Tapered pins need something to hold them in, make sure that is taken care of. From: "Nat Puffer" Subject: Re: COZY: New WEB Address - www.deford.com Date: Mon, 23 Nov 1998 15:22:03 -0600 Dear Mara, The ailerons should be cut out before doing any contouring, to keep them as light as possible. Lightness of the ailerons is the reason it is very bad practice to cover the wings with tri-ax cloth (as someone recommends). The two layers of UNI specified in the plans for the area over the ailerons makes them much lighter. We are trying to avoid any possibility of aileron flutter. A minimum of fill, primer, and paint should be used to finish the ailerons for this reason. Burt Rutan recommends keeping the ailerons as nose-heavy as possible. Nat ---------- > From: Mara Liston > To: cozy_builders@canard.com > Subject: Re: COZY: New WEB Address - www.deford.com > Date: Monday, November 23, 1998 12:34 AM > > Hi all! > > re: > >I have heard that some people contour the > >wing prior to cutting out the ailerons. Any comments from those who > >have been there on the pro's and con's of doing this? > > > > What about the layup that wraps from one side of the aileron, around the > counter weight and the torque tube in the aileron (A10?)and then back > down the other side of the aileron? I think that if you did the finish > contouring before you cut it out it might be a bit of a mess trying to > do that layup. I haven't finished the part of the wing around the > aileron yet, but I'm not anticipating too much trouble. > > The only other suggestion I have is that I think you mentioned putting > the winglets on before you start your finishing process. I am finishing > the bottom right now and am quite glad that I can put the wing on while > the plane is upside down. It makes it pretty easy to get nice even gaps > in between the cowl, strake and wing without having the plane quite high > off the ground or working on it from the underside. I try to avoid too > much sanding above my head, my arms are sore enough as it is from > sanding right side up! > > Almost done with the bottom, > > Mara Liston > N559CZ > > > > ______________________________________________________ > Get Your Private, Free Email at http://www.hotmail.com Date: Wed, 11 Nov 1998 01:49:33 +0100 From: Jean-Jacques CLAUS Subject: Re: COZY: Chap 19 - Aileron end ribs DeFord, Brian wrote: > > it > makes for an extremely small area to try and put two plies of BID! > / \ > / \ > / \ > / \________ > /_________________________________________O <- - - counterbalance > bottom skin > ^ > | > this is the area in question Brian, I did this 2 month ago. Like you i had a doubt before, but now i can tell you that there is no problem to put 2 plys of BID here ( with your fingers and micro arround of the 3/8" rod to avoid air bubbles). Don't hesitate to download all the previous discussion ( if not yet ) about placing the aileron's hinge ( it's really a shit to do this ! ). Hope that help you, Jean-Jacques CLAUS From: "Bill Kastenholz" Subject: Re: COZY: Chap 19 - Aileron end ribs Date: Wed, 2 Dec 1998 08:05:28 -0500 -----Original Message----- From: DeFord, Brian To: 'cozy_builders@canard.com' Date: Tuesday, December 01, 1998 6:47 PM Subject: COZY: Chap 19 - Aileron end ribs >Folks, > >I'm ready to build glass the end ribs on the aileron and was curious as to >how it should be done. Brian, I finished the ailerons over the past few months, and routed out the entire end area right up to the counterbalance weight. The bid I layed in one layer at a time with no trouble. I have a thin layer of micro over the very end of the steel rod, although it isn't really necesary. The micro allows you to sand the end perfectly flat. Bill Kastenholz wkasty@ix.netcom.com Date: Wed, 02 Dec 1998 07:57:21 -0500 From: David Domeier Subject: Re: COZY: Chap 19 - Aileron end ribs Brian, re "Should the foam be removed .04 inches in this area also with the rib going right up to the rod?" I'd take a bit more than .04 our of this area, then fill it with flox, and cover it with 2 plies of BID. It won't easily damaged should you drop it or bang the edge later on. dd From: "Brian & Susan DeFord" Subject: COZY: Chap 19 - Aileron end rib question Date: Tue, 1 Dec 1998 19:56:14 -0700 Folks, Sorry for the earlier message that came across like garbage. I was trying to ask about the details of the aileron end ribs and how far the rib should be built toward the counterbalance rod. Since the rod is 3/8" in diameter and it sits at the end of a 1-2" wide piece of foam of approximately the same dimension in thickness, it seems to me that it will be very hard to get two plies of BID in that area to form the rib. For those that have done this already, am I concerned for nothing? I'll try to illustrate in ascii art and I'll apologize ahead of time for those with a fixed pitch font editor - I'm using Microsoft's editor and it probably will look odd. This is the cross section of the aft end of the aileron: o <- elevator hinge \ \ \________ ___________O <- this is the counterbalance rod bottom skin The area I am questioning is right above the word "skin" - do you remove foam in this area as well to form the end rib? If so, is it difficult to get the BID in this small area? I hope this is clear enough. Any thoughts and/or comments would be appreciated. From: Epplin John A Subject: COZY: Composite joint bolt torque Date: Mon, 7 Dec 1998 12:30:37 -0600 I think there has been some discussion before but cannot put my finger on it at the moment. There are at least two places in the Cozy that have highly loaded critical bolted joints that are comprised of metal and composite materials. The two in mind are the engine mount to firewall and the wing to spar fittings. I would think using the published values from AC 43.13 would be excessive torque for these joints. It may be in the construction manual somewhere but I don't recall seeing it. There is a value for the lift tab attachment to the canard spar. Anyone care to comment? I just mounted the engine this past weekend, first of many times to come I am sure. John Epplin Mk4 #467 From: "Nat Puffer" Subject: Re: COZY: Composite joint bolt torque Date: Mon, 7 Dec 1998 15:07:08 -0600 Builders, I agree. I think Burt once said that 1/4" bolts would have been strong enough on the wings. With 1/2" bolts, you sure don't have to tighten them to the limit. Nat ---------- > From: Michael Pollock > To: Epplin John A > Cc: Cozy_builders@canard.com > Subject: Re: COZY: Composite joint bolt torque > Date: Monday, December 07, 1998 3:00 PM > > John Epplin wrote: > > >I would think using the published values from AC 43.13 would > >be excessive torque for these joints. John, > > > The bolts used to hold the wing to the carry through spar and the > canard tab bolts are in shear. I do not believe the maximum torque > value for the bolt should be used in these cases. On our Velocity, we > simply tighten the locknuts on those bolts with a 3/8" drive ratchet > until tight while someone moves the wing or canard up and down. We > have found that using a 3/8" ratchet and tightening as tight as we can > only gets around 35 foot-pounds of torque on the bolt. Just my .02 worth. > > Michael.Pollock@mci.com > Flying Velocity N173DT > Building Cozy MKIV #643 > > > > > Date: Mon, 07 Dec 1998 16:55:59 -0800 From: "LCDR James D. Newman" Subject: COZY: Re: Composite joint bolt torque Hi Nat and All, > Nat Puffer wrote: > I think Burt once said that 1/4" bolts would have been strong enough on the wings. He did - two 1/4" bolts minimum per wing (for a 1325 lb. Long-EZ). But felt many would not fly in it if he did, so he went with the 1/2" bolts. Three bolts are used so wing incidence and sweep can be adjusted/changed. > With 1/2" bolts, you sure don't have to tighten them to the limit. Concur. Infinity's Forever, JD From: mikefly@juno.com Date: Sat, 12 Dec 1998 00:29:59 -0600 Subject: Re: COZY: Chap 19 - Aileron end ribs Brian, I wasn't sure either, but recessed all of the foam, even up to the counter weight. Worked fine ! Good Luck MBB BTW Liked the art work ! From: "Tim" Subject: Re: COZY: Fwd: prefab parts Date: Wed, 16 Dec 1998 19:20:35 -0600 Merry Christmas Wes. Is cutting the cores out of the question? I have had very little foam cutting experiance before starting the Cozy IV. If you have a healper with a steady hand and follow the instructions and prepare everything before you start it is not that difficult. Good luck Tim -----Original Message----- From: Wesley Tidd To: cozy_builders@canard.com Date: Wednesday, December 16, 1998 7:00 PM Subject: COZY: Fwd: prefab parts > > > > > > Merry Christmas Everyone! > I,m new at this so everyone will have to be patient with me. I >> guessI have to agree with Larry on this subject. I am using all the >prefered >> parts on N569cz, my Cozy MK4. Featherlite main gear, thats installedand >the >> nose gear that I am currently working on. Hope I don't start something >here >> but here goes. I'm looking ahead to building my main wings. Aerocad " >sorry >> Nat " has precut foam wing cores for $800.00 and featherlite has them for >> $1200.00. My question is, is there any difference in these cores or am I >> wasting $400.00 for nothing. I am building my plane as close to Nat's >plans >> as possible and will probably buy the featherlite cores. I would like to >buy >> the cores to ensure that the airfoil is right and to save some time. I >> commend Nat on a beautiful plane. >> >> staighten up and fly right >> wes >> >> >> >> >> _______________________________________________________ >> Get your free, private e-mail at http://mail.excite.com/ > > > > > >_______________________________________________________ >Get your free, private e-mail at http://mail.excite.com/ > Date: Thu, 17 Dec 1998 10:07:37 +0100 From: Jean-Jacques CLAUS Subject: Re: COZY: Fwd: prefab parts At 16:19 16/12/98 PST, Wesley Tidd wrote: >>I'm looking ahead to building my main wings. Aerocad " sorry >> Nat " has precut foam wing cores for $800.00 and featherlite has them for >> $1200.00. I was worried before, now i can say you that it's easy and fun to do. It cost me a total of $600 of styrofaom plates (from Dow Chemical). With these plates i cut the 2 wings, the 2 winglets, the canard and the 2 elevators ( yes it's possible, after an hard discuss with the vendor ). >> I would like to buy >> the cores to ensure that the airfoil is right and to save some time. Your airfoil will be right if you cut them as per plans. You will not save a lot of time because the time you will wait from your supplier, the time you have to do yourself. Merry christmas from France, Jean-Jacques CLAUS - "No SANTA is not my uncle" From: "Brian & Susan DeFord" Subject: Re: COZY: Fwd: prefab parts Date: Thu, 17 Dec 1998 16:49:21 -0700 Wes asks: >My question is, is there any difference in these cores or am >I wasting $400.00 for nothing. I am building my plane as close to Nat's >plans as possible and will probably buy the featherlite cores. >I would like to buy the cores to ensure that the airfoil is right >and to save some time. I commend Nat on a beautiful plane. The last part of your post says you want to save time. The precut cores will certainly accomplish that as long as they ship them to you when you want them. I've recently finished my wings and went the route you are considering. I didn't have to build the templates or take the time to cut the cores. Both time savers. Is it worth $400 - you have to make that judgement. Some people spent $10,000 over sticker price to get a new VW beetle earlier this year! I guess in their mind it was worth it... As far as the quality goes, I think there are two factors - the templates and the cutting. If the templates are not very accurate you have already decreased the chances of "right" airfoils. A poor cutting job decreases it more. My wife and I cut the cores for my canard and I KNOW we could have done the same quality work on the wings as well. It isn't that hard if you take the time to do it well. I wasn't as happy with the quality I received on my pre-cut cores. For whatever reason, the aileron cutouts weren't right and I had to do a repair job which cost be time. My point in saying that is that just because someone will build the part for you doesn't mean you will get a perfect part. I did a stupid thing and trusted that they were indeed perfect. Not until I had glassed the wing did I reveal the problem - too late to get it exchanged! So - check all of your pre-fab stuff when you get it that it meets the requirements of a part you would have built yourself. I think in most cases you will be satisfied. Regards, Brian DeFord brian@deford.com http://www.deford.com/cozy From: cdenk@ix.netcom.com Date: Thu, 17 Dec 1998 18:41:19 -0600 (CST) Subject: Re: COZY: Fwd: prefab parts I with various others hot wired all normal things and a few not normal. Usually I had trained help, but when the time came to do the canard, no one was available, and I enlisted, NO! drafted the aid of my wife for a first time. The cores came out perfectly!! Usually there are templates available for borrowing. Use care that the templates are accurate, then its almost difficult to make a bad hot wire job. Also in shipping the hot wired pieces are subject to damage. Date: Thu, 17 Dec 1998 20:51:28 -0500 From: Bulent Aliev Subject: Re: COZY: Fwd: prefab parts I did two sets (for me and Todd Silver) of wings, winglets etc. in two steps. The first step was hot wiring the cores about 1/8" over size with over sized templates. Then mounting the real template made of aluminum and match drilled with the first one. Sending with long sending block to final shape. All the cores came perfect. One of them is shown in the last newsletter with Todd Silver's name underneath?? He was my hot wire man. The advantages are: If you or your helper are not experienced, there is one more step to fix screw ups. Hot wire always leaves some ridges and valleys that you must fill or sand anyway. My cores came finished ready to glass. If anyone needs details, please let me know. I know this is old news to some but may help someone that is getting ready to do his wings. Regards Bulent 954 524-3284 From: cdenk@ix.netcom.com Date: Fri, 18 Dec 1998 17:26:40 -0600 (CST) Subject: Re: COZY: Fwd: prefab parts Much important to spend time aligning the cores before every layup. I don't mean measuring to the jigs, but to the actual foam using the dimensions on the wing plan view. The waterlines of the leading and trailing edges are there. Make concave templates that set on the foam surface to mark the leading edge reference waterline. I still think hot wiring is one of neat fun things to do!! Not difficult, quick results, not much time required. I probably spent 3 times the wing hot wire time aligning the cores, shimming the jigs with stirring sticks. Used 3 string lines with wing on edge, 1 top offset from leading edge waterline, one directly (plumb bob) below at trailing edge, one offset from trailing edge (measure from the other bottom line). Put together all cores fore and aft, checking location, shimming from jigs. When happy, remove top (leading) section and layup spar diagonal plys. Then install leading section shimming from jigs. From: "Hunter Welch" Subject: Re: COZY: Fwd: prefab parts Date: Thu, 17 Dec 1998 22:18:11 -0800 Hello all, Just to put my 2 bits in.. I was concerned about the airfoils also. I had featherlite precut my cores for the canard and it came out great. I became ambitious on the wings.. I ended up redoing the wing and now have a wing that has some less than smooth areas that will need extra fill when I begin that wonderful job (fill/sand/fill/sand.....) I recommed getting the precut cores. True, they might have a bad day and cut something incorrect, but they do present themselves as a business that does this type of work, thus they are liable to create an accetable product. You make a mistake...you are responsible! Bill w From ???@??? Sat Dec 19 17:51:54 1998 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 HAA26782 for ; Sat, 19 Dec 1998 07:16:29 -0500 (EST) Received: (from majordomo@localhost) by twc2.betaweb.com (8.8.5/8.8.5) id HAA22307 for cozy_builders-list; Sat, 19 Dec 1998 07:14:12 -0500 X-Authentication-Warning: twc2.betaweb.com: majordomo set sender to owner-cozy_builders@betaweb.com using -f Received: from x5.boston.juno.com (x5.boston.juno.com [205.231.100.23]) by twc2.betaweb.com (8.8.5/8.8.5) with ESMTP id HAA22300 for ; Sat, 19 Dec 1998 07:14:08 -0500 From: mikefly@juno.com Received: (from mikefly@juno.com) by x5.boston.juno.com (queuemail) id DWT3SUME; Sat, 19 Dec 1998 07:13:54 EST To: jkl@sonet.net Cc: cozy_builders@canard.com Date: Sat, 19 Dec 1998 06:15:11 -0600 Subject: Re: COZY: Fwd: prefab parts Message-ID: <19981219.061519.-817761.2.mikefly@juno.com> X-Mailer: Juno 2.0.11 X-Juno-Att: 0 MIME-Version: 1.0 Content-Type: text/plain Content-Transfer-Encoding: 7bit Sender: owner-cozy_builders@betaweb.com Precedence: bulk Reply-To: mikefly@juno.com X-UIDL: 2a66862d20be1c3d3ba14456bb4d3177 On Wed, 16 Dec 1998 19:20:35 -0600 "Tim" writes: >Merry Christmas Wes. > Is cutting the cores out of the question? I have had very little >foam >cutting experiance before starting the Cozy IV. If you have a healper >with a >steady hand and follow the instructions and prepare everything before >you >start it is not that difficult. >Good luck Tim I agree, Cutting my cores was easy and FUN ! Mike Bowden