From: Militch@aol.com Date: Sun, 24 Jan 1999 18:53:40 EST Subject: COZY: Aft landing gear attach bulkhead I looked in the archives, but didn't find an answer. The drawing for the aft landing gear attach bulkhead shows the orientation for the 8 layers of uni on one side and the three on the other side. I interpret the drawing to mean that the uni does not cover the entire bulkhead, but is layed on the left side at 340 degrees true and on the right side at 20 degrees true (the bottom of the bulkhead being on the 90/270 degree line) in such a way that it covers that the bulkhead tab and a lower section formed by extending a line from the inner edge of the tab. Is this correct? Thanks also for the replies I received on angle measurement tools. Thanks, Peter Militch Cozy Mark IV #740 Date: Sun, 24 Jan 1999 22:27:09 -0500 From: "Marc J. Zeitlin" Subject: Fwd: COZY: Aft landing gear attach bulkhead Peter Militch wrote: >I looked in the archives, but didn't find an answer. The right first sentence :-). >......layed on the left side >at 340 degrees true and on the right side at 20 degrees true (the bottom of >the bulkhead being on the 90/270 degree line) in such a way that it covers >that the bulkhead tab and a lower section formed by extending a line from the >inner edge of the tab. That's how I did it. -- Marc J. Zeitlin marcz@ultranet.com http://www.ultranet.com/~marcz/ From: lschuler@cellular.uscc.com Date: Mon, 25 Jan 1999 09:07:49 -0600 Subject: Re: COZY: Aft landing gear attach bulkhead Peter Militch wrote: >The drawing for the aft landing gear attach bulkhead shows the orientation >for the 8 layers of uni on one side and the three on the other side. >snip Sounds like you read it the same way I did. Larry Date: Thu, 25 Feb 1999 17:18:39 -0500 From: "Marc J. Zeitlin" Subject: Fwd: Re: COZY: seatback sides bil kleb writes; >"Mark D. Wunduke" wrote: >> >> Are these "sides" glass over or are they left bare foam >> to be later floxed at the joining of the fuselage. > > 4.6 - Do you cover the cutout areas (notches) in the seat > back with BID or leave them uncovered? > > There's no need to cover the notches or exposed foam. You'll > apply flox to the exposed edges and 2-BID tape the entire seat > back in place during fuselage assembly in Chapter 6. I believe Mark was referring to the SIDES of the bulkhead, not the notches. In this case, refer to figure 5, section A-A on page 1 of Chapter 4. You can see that the 1 BID of glass does in fact, wrap over the sides of the bulkhead, as well as over the flox corners on the top and bottom. If the FAQ is really addressing this issue, then it should probably be changed to indicate the correct procedure as shown in the plans (although I would probably agree that structurally it wouldn't make a difference if you wrapped the glass over the sides or not - on none of the other bulkheads is that done). -- Marc J. Zeitlin marcz@ultranet.com http://www.ultranet.com/~marcz/ From: "John Slade" Subject: COZY: Chap 4 - foam cutting Date: Sun, 7 Mar 1999 09:50:32 -0500 I cut my F22 last night. It went very well. I've read lots of archive stuff about CAD, tracing, drawing accuracy etc. and I thought I'd share the method I used. On the theory that I'm building only one of these I cut up the M4 drawing so I could see the critical edges. Following the layout diagram in Chap 2, I laid the drawing upside down on the left side of the foam, pinned it in place and used a v sharp pencil to poke through the lines. Then I laid the drawing right side up on the right side of the foam matching the center line and poked some more. Once the drawing was removed I had a "join the dots" shape. I drew the lines in pencil, then checked the measurements between various lines with those on the drawing. I cut with a stanley knife and had a nice looking F22 & doubler in about 1 hour. Looking at someones pictures of F22 on their web site helped. I couldn't find anything in the plans about cutting the doubler - just the layout in Chap 2 and placing it later. Not much on M4 about it either. A few words about the doubler on M4 would have helped. (next edition, Nat?). In general the plans drawings worked well once I figured them out. Someone in the archives said keep the big picture in mind, so I thought about where the curve I was cutting would go in the airplane. The curve which matches the fuselage I cut REAL carefully. The one above my legs in the cutout I cut with care, but a little faster knowing this just had to be close and look good. One question: The pieces needed to join the top and bottom of F22 are really small - about 1.5 inches. Why does the Chap 2 foam layout show them coming from three seperate pieces of scrap? John Slade From: cdenk@ix.netcom.com Date: Sun, 7 Mar 1999 10:05:01 -0600 (CST) Subject: Re: COZY: Chap 4 - foam cutting Was Said I heartly recommend keeping the originals intact! Although this one might never be used, I have numerous times referred to the originals for details and dimensions in the 5 years of flying. From: "John Slade" Subject: COZY: Chap 4 - foam cutting Date: Sun, 7 Mar 1999 12:02:16 -0500 >Was Said >I heartly recommend keeping the originals intact! Although this one might never be used, I have numerous times referred to the originals for details and dimensions in the 5 years of flying. I put the pieces of the originals in an envelope attached to my plans. Nothing is lost. From: "Nat Puffer" Subject: Re: COZY: Chap 4- Instrument panel drawings Date: Mon, 8 Mar 1999 14:16:37 -0600 John, Both work, but I like M-3 best. Nat ---------- > From: John Slade > To: Cozy Builders > Subject: COZY: Chap 4- Instrument panel drawings > Date: Sunday, March 07, 1999 9:17 PM > > Its me again. > I'm ready to cut out the instrument panel, then I noticed an anomoly in the > drawings / pictures. > The two photo's of the instrument panel on page 4.4 clearly show material > around the hole for the electrical conduit. The edge of the hole appears to > be parallel to the slightly larger cutout above it. Page 4.2 Fig II shows > the elect hole offset further to the right so that it intersects with the > edge of the panel. The drawing M3 agrees with page 4.2 fig II. Was the plan > for the elect conduit moved after the photos were taken? > > I took me a while to figure out that "before carving" and "after carving" on > M4 refer to the fuslage bottom construction. > John Slade > > Date: Mon, 15 Mar 1999 11:04:51 -0500 From: Austin Subject: COZY: Trouble visualizing! Builders, I think I have built it right, but I still cannot figure out this view in my plans (#706). Chapter 4 Page 1. In the lower right hand corner, Fig. 5 is comprised of two seperate drawings. The upper drawing on the work bench is easily understood. My brain refuses to understand the lower drawing. I know that I am NOT supposed to round and glass the side edges of the seatback.What edge is this drawing looking at? The seatback turned out pretty nice (I think?). It's probably obvious, but I just don't see it. Thanks, John Austin Millington Date: Mon, 15 Mar 1999 12:00:16 -0600 From: "Joseph H. Hart IV" Subject: Re: COZY: Trouble visualizing! Austin wrote: > I know that I am NOT supposed to round and glass the > side edges of the seatback.What edge is this drawing looking at? John: I am not at home so I can't look at my seatback; however, I seem to recall having the exact same question and posting it back in October or so of last year. As I recall, you DO round the sides of the seatback. I never understood why, unless it was simply for practice! Check the archives to confirm what I am saying. Good luck with your project. Jody Hart Date: Mon, 15 Mar 1999 11:14:37 -0800 From: Michael Antares Subject: Re: COZY: Trouble visualizing! At 11:04 AM 3/15/99 -0500, you wrote: >Builders, > I think I have built it right, but I still cannot figure out this >view in my plans (#706). Chapter 4 Page 1. In the lower right hand >corner, Fig. 5 is comprised of two seperate drawings. The upper drawing >on the work bench is easily understood. My brain refuses to understand >the lower drawing. I know that I am NOT supposed to round and glass the >side edges of the seatback.What edge is this drawing looking at? The >seatback turned out pretty nice (I think?). > It's probably obvious, but I just don't see it. >Thanks, >John Austin Millington > The reason for the rounding is that it is impossible to make a right angle bend with the fiberglass and still have it attached to the foam. ALL corners that glass has to form around will have a radius either by rounding the foam or by making a radius with micro (in the case of an inside right angle bend). Hope this helps! Good luck on your project... 11597 Summerhome Park Road Forestville, CA 95436 707.887.7260 Cozy#413 Finished through chap 14 except chap 13. Chaps 16 & 24 mostly finished. Chapters 20 and 21 finished. Date: Mon, 15 Mar 1999 13:28:21 -0500 From: bil kleb Subject: Re: COZY: Trouble visualizing! Austin wrote: > > I know that I am NOT supposed to round and glass the > side edges of the seatback. ah, but you are. > What edge is this drawing looking at? this second drawing is section a-a (the orientation of the section is indicated on the "work bench" sketch above). it shows a view as you were looking from the top or bottom of the airplane,* so you see that the starboard and port edges of the bulkhead are indeed rounded (per chapter 3 instructions about rounding for glass to conform to outside corners). *actually not quite correct: above and below the airplane in the sense of being in the plane of the installed seatback (i.e., about a 37 deg inclined plane from the vertical). -- bil From: jetpilot@execpc.com Date: Sat, 3 Apr 1999 19:38:09 -0600 Subject: COZY: Aft Landing Gear Attach Bulkhead Hi builders, I have a question concerning the aft gear attach bulkhead on drawing M-6. On the foward face where you have to lay 8 plies of UND at the shown angle, is that in all one angle all the way across the front face or is it to the center and since when we had to trace the drawing then flip it over to get the identical side, do we lay the 8 plies of UND at that angle also and just meet in the middle. (Like a big "V" shape on the foward face). This may sound stupid, but I had to ask. Will the UND look like this\\\\\\\\\\\\\\\\\\ or like this \\\\\\\\\\\\\\\\////////////////////. Any advice would greatly be appreciated. Mark Wunduke, builder #748 Date: Sun, 04 Apr 1999 14:58:44 -0500 From: Michael Amick Subject: Re: COZY: Aft Landing Gear Attach Bulkhead jetpilot@execpc.com wrote: > Ref: aft gear attach bulkhead on drawing M-6. > On the foward face where you have to lay 8 plies of UND at the > shown angle, is that in all one angle all the way across the front face ... > or is it to the center...... The 8 extra plys are added only on the ends of the bulkhead, not all the way across. > Wil the UNI lok like this\\\\\\\\\\\\\\\\\\ or like this > \\\\\\\\\\\\\\\\////////////////////. More like this \\\ /// Michael Amick From: "Denis Thomassin" Subject: RE: COZY: Aft Landing Gear Attach Bulkhead Date: Mon, 5 Apr 1999 13:57:40 -0400 I had the same interrogation when it came to apply the 8 layers on the Aft Gear Attach. Since I consider myself a man of compromise I finished doing 4 layers one way / and 4 others one the other way \ alterning between each one each time. So I go a 8 play X at 20 degrees angles. What do you think? should I put the piece on the wall with a label that say: " Flying is no compromise" or use it like that ? Happy Easter to all. Denis Thomassin Montreal, Canada 705 From: "Russ Fisher" Subject: Re: COZY: Aft Landing Gear Attach Bulkhead Date: Mon, 5 Apr 1999 17:29:24 -0400 > So should the front face look like this\\\\\\\\\\\\\\\\\\\\\\\\\ or would it > look more like this with the angles meeting in the > center\\\\\\\\\\\\\\\\\\\\\\//////////////////////////// (like a big "V"). Any > advice would be greatly appreciated. Mark Wunduke, builder #748 Howdy, Had the same question and posed it to Nat just for confirmation. He countered with the question, "In which direction does UNI give its strength?" The answer, of course, is along the length of the fibers. The strength we are looking for here is in the vertical or near vertical direction, actually angled upward and out from the center of the bulkhead. It is also only required locally on the outside "ears" of the panel. The vertical UNI layers DO NOT go all the way across. If you draw an imaginary line from the inside of the "ears" all the way down to the bottom, that is where the edge of the 8 & 3 layer UNI layers stop - all layers running parallel to that line. Therefore the layups should look something like: |\\ //| |\\\\ ////| |\\\\\\=x=x=x=x=x=//////| |\\\\\\\\=x=x=x=x=////////| with the =x= indicating the BID and horizontal UNI layers. I did run the horizontal UNI layers all the way up so I wouldn't have a bump on the ears where the landing gear will attach. See ya, Russ From: "Russ Fisher" Subject: COZY: Chap 4 - Blind screws in firewall Date: Mon, 5 Apr 1999 22:59:06 -0400 Hi folks, Well after 15 months, I'm embarrassed to say, I'm back to work on my Cozy. Did a little home remodeling and took _just_ a little longer than I thought. Anyway, in reading some posts from a few months ago, I came upon an idea for fixing the firewall blind screws in place. My plan is to use a cut-off wheel in a Dremel and cut a 1/16" slot in the head extending into the plywood about 1/2" on either side of the screw. Then I can insert a piece of 1/16" music wire in the slot and it shoud prevent the screw from turning. I will try to undercut the slot slightly (like a dovetail for you woodworkers) so that if the flox should break loose, the torque will keep the wire in the slot rather than ejecting it. In cross section, it should look something like: __________ __________ /O\ _______________________ Top view: =======(==)======== This method relies completely on mechanical forces rather than a weld or solder joint on a backing plate like some have suggested. I'll let you know how it turns out. Russ Fisher rfisher@spacetech.com Date: Tue, 06 Apr 1999 08:32:47 -0500 From: Michael Amick Subject: Re: COZY: Aft Landing Gear Attach Bulkhead The purpose of this bulkhead is to transfer the landing load to the fusalage sides & the spar. Your description say you made the part incorrectly. It will weigh more and be weaker than the design specifies. It is not very expensive to correct now. In my opinion there is no choice here: Make the part over and read all directions more carefully in the future. If English is difficult for you GET HELP!! In the air, you do not want to HOPE everything is correct; you want to KNOW!! Michael Amick Denis Thomassin wrote: > I had the same interrogation when it came to apply the 8 layers on the Aft > Gear > Attach. Since I consider myself a man of compromise I finished doing 4 > layers > one way / and 4 others one the other way \ alterning between each one each > time. > So I go a 8 play X at 20 degrees angles. > > What do you think? should I put the piece on the wall with a label that say: > " Flying is no compromise" or use it like that ? > > Happy Easter to all. > > Denis Thomassin Montreal, Canada 705 From: "Russ Fisher" Subject: Re: COZY: Aft Landing Gear Attach Bulkhead Date: Tue, 6 Apr 1999 23:28:51 -0400 Michael Amick wrote: > Make the part over and read all directions > more carefully in the future. If English is difficult for you GET HELP!! > In the air, you do not want to HOPE everything is correct; you want to >KNOW!! Michael, If everyone understood everything in the plans, there would be no need for this forum. Insults do not belong here, please take them somewhere else. Russ Fisher From: "John Slade" Subject: Re: COZY: Aft Landing Gear Attach Bulkhead Date: Wed, 7 Apr 1999 02:18:20 -0400 Russ. I doubt that our friend in Canada took that as an insult, rather good advice; and I doubt that an insult was intended. The plans are complex enough that, in a second language, interpretation must be difficult at times. Email lacks body language and expression, hence the :} etc. and is far from a perfect communication medium. Don't react so strongly to what you think was meant by someone else's text. Personally I welcome dumb questions and blunt answers. I have posed a few of the former and received a few of the latter myself. Regards, John Slade #757 Cozy progress site http://kgarden.com/cozy > >Michael Amick wrote: >> Make the part over and read all directions >> more carefully in the future. If English is difficult for you GET HELP!! >> In the air, you do not want to HOPE everything is correct; you want to >>KNOW!! > Russ Fisher wrote >If everyone understood everything in the plans, there would be no need for >this forum. Insults do not belong here, please take them somewhere else. From: cdenk@ix.netcom.com Date: Wed, 7 Apr 1999 16:29:26 -0500 (CDT) Subject: Re: COZY: Aft Landing Gear Attach Bulkhead Was said I don't believe there are any dumb questions, therefore, I don't react to dumb questions, just all questions Some answers need to be blunt, many times the answer could have been worded more graceful, the important issue is THE ANSWER. For those, whose native language in not American (Queen's English is different), don't be shy at speaking, prehaps a little different wording will clear the issue. Example: At work the Cad software package I use, says "don't copy" when you wnat to copy, very strange. Date: Thu, 08 Apr 1999 13:41:34 -0500 From: Michael Link Subject: Re: COZY: Chap 4 - Firewall hardpoints Russ Fisher wrote: > I read in the archives where someone recommended making the upper firewall > hardpoints 2" long in the vertical dimension. For those of you who have > mounted your engine, have you found it difficult to hit these? > > Russ Fisher Russ, Like about everything in the Cozy plans, if you build it to the listed dimensions, it fits. My engine mounts lined up in the center of the hardpoints.(I used the Cozy approved engine mount supplier). Regards, Michael Link Cozy MK-IV N-171-ML Date: Thu, 08 Apr 1999 18:15:01 -0400 From: "Marc J. Zeitlin" Subject: Fwd: Re: COZY: Chap 4 - Firewall hardpoints >Russ Fisher wrote: > >> I read in the archives where someone recommended making the upper firewall >> hardpoints 2" long in the vertical dimension. For those of you who have >> mounted your engine, have you found it difficult to hit these? While I would agree with Michael Link that if you build it to the plans it'll work fine (I did, and it did), I was a little nervous about hitting everything dead nuts on center (which I didn't - a couple of the bolts are 1/4" or so off center of the aluminum insert). If I was to do it again, I'd probably make the inserts 1.5" square, just to allow for more variability in my positioning and in the engine mount manufacturing. -- Marc J. Zeitlin mailto:marcz@ultranet.com http://www.ultranet.com/~marcz/ Date: Sat, 10 Apr 1999 20:59:48 -0400 Subject: COZY: Ch 4: Fwd Landing Gr Bulkhead 1/4" hole placement From: Dana Hill Dear Builders, Please Help.............. Upon preparing the fwd landing gear lower bulkhead for floxing into the fuselage I measured for drilling the two required 1/4" holes. It turns out that the M drawing of this bulkhead shows a locating dimension for this hole at 4.3" up from the bottom edge. Measuring the drawing shows about 4.1". My guess is, is that the vertical location of these holes is very important, ie. fixing the eventual height of the landing gear with respect to the fuselage. Did anyone else run into this? Would appreciate any help. I do not recall seeing anything in the archives about this. If I missed it please steer me in the right direction. ________________________________ Thanks in advance, Dana Hill CZ IV #676 ___________________________________________________________________ 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/getjuno.html or call Juno at (800) 654-JUNO [654-5866] Date: Sun, 11 Apr 1999 23:06:26 -0400 Subject: COZY: Ch 4: Fwd Lower Landing Gr. Bulkhead 1/4" holes From: Dana Hill Thanks to all for the help. For those interested, it turns out that the 4.3" dimension (in M-5 or 6) was included as a change in Newsletter #38, from 4.1". However it confused me because the location of the hole on the M drawing scales to the original dimension. I guess the lesson I learned here was: a. Trust indicated dimensions before its corresponding scaled dimension b. If building from 2nd set of CZ IV plans (tan cover) it's still good to be aware of changes to plans listed in the pre- #52 newsletters ____________ Dana Hill CZ IV #676 ___________________________________________________________________ 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/getjuno.html or call Juno at (800) 654-JUNO [654-5866] From: "Russ Fisher" Subject: COZY: Chap 4 - Firewall rudder cable pulley location Date: Mon, 19 Apr 1999 21:26:47 -0400 In the Cozy Newsletter 39 page 4, correction #3 states to locate the two groups of three blind screws 2.0 inches higher than shown on M-7 & M-8 to provide more clearance between the rudder cable and the aileron push rods. This newsletter was pre-second edition of the plans. Since a number of corrections had been inadvertently omitted from the second edition (which I have), I called Nat to find out if the change had been made. He said he couldn't remember, but if the pulley got in the way to just add a couple of washers under one or two screws to "tilt" the pulley in the direction needed. I understood what he meant, but I couldn't get him to understand that all the washers you could possibly fit under a screw was not going to make up for 2 inches! Trouble is, if the plans had been corrected, then the original location would have been just barely above the lower longeron. If not, then when I move the screws up 2 inches, they will be just BELOW the upper longeron. Could he possibly have meant 0.2 inches? Could someone who has a functional control system installed measure the distance from, say, the bottom of the upper longeron to the center of the uppermost screw and let me know the distance? Thank you. Russ Fisher Date: Mon, 31 May 1999 10:02:03 -0400 From: Phillip Subject: COZY: F22 Hi folks, How do I put this......I have a ......."FRIEND" who after making the F22 bulkhead realized "HE" made a mistake. It appears that I ..........I mean my "FRIEND".....in doing the local layup of 5 UND and 4 BID.....covered the entire forward bulkhead instead of just the left and right first five inches at the top and the left and right sides as depected on FIG 10 on page 4-2. Do I.... I mean "HE" need to make the entire bulkhead over, or can it be used as is...and just accept the additional weight? It hasn't been weighed yet, but it will obviously be heavier. Any advice would be appreciated. Thanks, Phillip Sill Chapter 4, #707 From: SWrightFLY@aol.com Date: Mon, 31 May 1999 13:19:12 EDT Subject: Re: COZY: F22 In a message dated 5/31/99 9:05:03 AM Central Daylight Time, LUV2AV8@compuserve.com writes: << "HE" need to make the entire bulkhead over, or can it be used as is...and just accept the additional weight? It hasn't been weighed yet, but it will obviously be heavier. Any advice would be appreciated. >> Phil.... .Should you ever decide to install a Nose Lift you will have already done the reinforcement needed for the installation of the unit. You have done an excellent job of planning ahead. Steve Wright Stagger EZ N700EZ Wright Aircraft Works LLC: Electric Nose-Lift for EZEs Date: Mon, 28 Jun 1999 14:27:09 -0400 From: George Berven Subject: COZY: Ch. 4: Firewall bulkhead Quick question, On the firewall bulkhead, the upper and lower sections are to be cut out of the birch plywood? If so I get dimensions from the drawing of (24.5" height by 37.25" width). In my shipment I recieved one 1/4" birch plywood [24" x 48"]. I seem to be short by 0.5" of plywood. Did anyone else have this problem. I probably have some sort of concept error that I just haven't resolved. If not, what's the deal? Thank you, George... gberven@erols.com From: "John Slade" Subject: Re: COZY: Ch. 4: Firewall bulkhead Date: Mon, 28 Jun 1999 15:04:43 -0400 George, Fit the curved part of the upper piece into the NACA cutout in the lower piece & you'll get the missing half inch back. There is a picture somewhere in plans that shows this. John Slade http://kgarden.com/cozy >On the firewall bulkhead, the upper and lower sections are to be cut out >of the birch plywood? If so I get dimensions from the drawing of (24.5" >height by 37.25" width). In my shipment I recieved one 1/4" birch >plywood [24" x 48"]. I seem to be short by 0.5" of plywood. Did anyone >else have this problem. I probably have some sort of concept error that >I just haven't resolved. If not, what's the deal? Date: Mon, 28 Jun 1999 16:16:46 -0400 From: George Berven Subject: Re: COZY: Ch. 4: Firewall bulkhead Thanks, Just noticed picture on page 4-4. Concept error resolved. gberven@erols.com Date: 28 Sep 99 21:07:48 MDT From: Brian Norquist Subject: COZY: making less work for the trauma surgeon I'm thinking of making the legholes taller (Chapter 4) by an inch or so and filling the extra space with a high density foam. The foam will also be wider and will extend back under the instrument reinforcement bar. The idea is to reduce edges, provide more surface area to spread out the contact with the legs and absorb energy with HD foam. I will probably also cover all edges of the legholes with an automotive dashboard material. I've heard the Renault material is very good. My questions are: Should I laminate this foam or just cover it (perhaps just one BID?) Will I need to reinforce the instrument panel more? Is there a better energy absorption material to use for lining the legholes? Are there other edges that also should be analyzed in terms of their occupant interface during a crash? ____________________________________________________________________ Get free email and a permanent address at http://www.netaddress.com/?N=1 From: "John Slade" Subject: Re: COZY: making less work for the trauma surgeon Date: Tue, 28 Sep 1999 23:48:04 -0400 > Are there other edges that also should be analyzed in terms of > their occupant interface during a crash? What about the back of the front seat headrest? I've seen a couple which were so sharp you'd end up with the rear seat passenger's head in your lap if you stopped too quick and they didnt have a full harness on. From: "Jim White" Subject: Re: COZY: making less work for the trauma surgeon Date: Tue, 28 Sep 1999 21:44:15 -0700 Save yourself a lot of time and trouble and build it like it is shown in the plans. Resist the urge to change anything. Believe me, you will have a much safer airplane if you do. When I first started, I too thought of making changes. In the end, most changes end up adding weight and/or taking way more time to complete. Significant improvements to the design, especially in the early chapters are few and far between. These chapters have been heavily scrutinized by the 1600+ plans owners and builders, not to mention the 1000++ that reviewed the Long-Ez plans when they were available. A majority of Cozy's end up weighing more than they need too. Your best bet for avoiding a visit to your emergency ward is to keep it simple, lightweight, and put in a reliable engine. Heavy airplanes with big engines may take off and climb faster, but they also land faster. Enjoy, Jim White -----Original Message----- From: Brian Norquist To: cozy_builders@canard.com Date: Tuesday, September 28, 1999 8:37 PM Subject: COZY: making less work for the trauma surgeon >I'm thinking of making the legholes taller (Chapter 4) by an inch or so >and filling the extra space with a high density foam. Date: Wed, 29 Sep 1999 10:31:12 -0500 From: Bulent Aliev Subject: Re: COZY: making less work for the trauma surgeon Brian Norquist wrote: > > Will I need to reinforce the instrument panel more? > > Is there a better energy absorption material to use for lining > the legholes? > > Are there other edges that also should be analyzed in terms of > their occupant interface during a crash? I would reinforce the seat belt hard poits instead. It may make a difference between open and closed casket...:) > > > ____________________________________________________________________ > Get free email and a permanent address at http://www.netaddress.com/?N=1 From: cdenk@ix.netcom.com Date: Wed, 29 Sep 1999 17:09:08 -0500 (CDT) Subject: Re: COZY: making less work for the trauma surgeon On 09/28/99 21:07:48 you wrote: > >I'm thinking of making the legholes taller THat means the instrument panel vertical space will be reduced. Per the drawings, there is just enough space to get two 3.125" gauges (airspeed, dg, roate of climb, altimeter, etc) above each other. This provides a standard instrument layout. Also an IFR panel radios take space. More important pilot has good instrument layout for safety. Remember, 1st priority is "Fly the Plane". From: "Rick Maddy" Subject: COZY: Novice Chapter 4 Questions Date: Thu, 28 Oct 1999 21:48:22 -0600 I'm being a good boy and studying the plans in detail in preparation for building. While studying chapter 4 I came across several questions. I scoured the archives and had some questions answered. I read ALL the chapter 4 postings and all the Peel Ply postings. What follows is a list of very specific questions I didn't find answers for. Please keep in mind I have only studied chapter 3, I haven't built the educational stuff. 1) Chapter 4, page 1, figure 6. I read all about how the diagrams aren't perfect with regard to sizes but... This figure shows several fractions that add up to 28.0". Chapter 4 page 1, figures 1 & 2 show the foam as 28.8" - 0.75" for angle = 28.05". I know 0.05" isn't much and I wouldn't bring it up except someone sent me an email indicating that several builders had trouble with the seatback being too short. Maybe it needs to be 29.0". Anyone experience this? 2) I was trying to visualize the 1 BID on the back of the seatback. It covers the aft face, the left and right sides, and the angled bottom. That I got. My question was how well does the glass sit where the sides and angled bottom meet? Do the cut out corners help? It's probably obvious if I was doing it but I can't yet. 3) I read that you don't cover the cutouts of the bulkheads but I just want to confirm this on the seatback since it is the only bulkhead that have the sides glassed. Is the end result of the seatback as if the corners where cut out after all the glass was applied? 4) A peel ply question I didn't see in the archives. The plans say to peel ply the edges of the aft face ply. Is this just the left and right edges or does this include the angled bottom edge too? If so, why don't the plans mention anythings about peel plying the angled top edge. 5) On F-22 the plans say to press the doubler into place on the wet layup. The plans don't mention to micro the face of the double first as is indicated as a standard practice in chapter 3. The plans do state to micro the aft face of the doubler before glassing it though. Should I micro the forward face of the doubler before pressing it into place? 6) After glassing the aft face of F-22 the plans say to weight bulkhead flat for cure. It then says to use peel ply and wax paper. Should the whole face be peel plyed or just the overlap of the UND from the doubler? 7) Is the whole aft face of the IP peel plyed or just the area above the leg holes? 8) There is no cross section of the vertical ribs on the forward face of the IP. Do these have channels as well? Seems like they wouldn't but I'm not sure. What did you do? 9) Picture of firewall on page 4 shows different cutout location for electrical than is shown on drawing M-3. I know not to cutout the holes until assembly but which is right - the picture or the drawing? 10) The plans say to do some sanding on the IP to prepare for the rib installation. Wouldn't it be easier to peel ply where the ribs will go instead? Is this acceptable? 11) Same issue with landing gear bulk hard points. Should the hard points be peel plyed instead of sanding after installtion into bulkheads? 12) Plans say to micro forward surface of landing gear bulkhead (as expected). I just want to confirm that this doesn't include the hard points (since chapter 3 says not to micro between two layers of glass). 13) Any advice on cutting square holes like those on the firewall? 14) Last one - I read all the debates on peel ply (only where needed vs. everything). The entries in the archive for peel ply only go through December '97. I just wondered if there was an update. It seemed pretty even but maybe leaned in the direction of peel plying everything. Any thoughts? (silly question :) ) I think I'm in trouble. This many questions for such a simple chapter. I'm one of those people who measure everything to the nearest 64th of an inch. Heck, I was measuring drywall to the nearest 16th of an inch for my garage and got mad when there was an 1/8" gap! Hopefully I quickly learn when to pick my battles. I'm sure many of you have gone through this. Off to tear apart chapter 5 while I wait for all your wisdom to these questions. Thanks, Rick Maddy (cozy@maddyhome.com) Cozy Mk IV #0824: Pre-build (www.maddyhome.com/cozy) From: Militch@aol.com Date: Fri, 29 Oct 1999 10:02:13 EDT Subject: Re: COZY: Novice Chapter 4 Questions Here is my input: Regarding a message dated 10/29/99 3:50:53 AM, in which cozy@maddyhome.com wrote: >1) Chapter 4, page 1, figure 6. I read all about how the diagrams aren't >perfect with regard to sizes but... This figure shows several fractions >that add up to 28.0". Chapter 4 page 1, figures 1 & 2 show the foam as >28.8" - 0.75" for angle = 28.05". I know 0.05" isn't much and I wouldn't >bring it up except someone sent me an email indicating that several builders >had trouble >with the seatback being too short. Maybe it needs to be 29.0". Anyone >experience this? The seatback was fine as built for me. The trick was to install it so the top is flush with the top of the sides and the bottom is flush with the bottom. If that means it's actually at a 46 degree angle instead of 45, then that's the way to install it. > >2) I was trying to visualize the 1 BID on the back of the seatback. It >covers the aft face, the left and right sides, and the angled bottom. That >I got. My question was how well does the glass sit where the sides and >angled bottom meet? Do the cut out corners help? It's probably obvious if >I was doing it but I can't yet. Not great - I had a couple of strands / air-bubbles sticking out here and there. It gets covered by flox when you install the seatback, so it did not appear to be a cosmetic or strength issue. I sanded it flush, and think I then put small patches on just to be safe. > >3) I read that you don't cover the cutouts of the bulkheads but I just want >to confirm this on the seatback since it is the only bulkhead that have the >sides glassed. Is the end result of the seatback as if the corners where >cut out after all the glass was applied? Yes. >4) A peel ply question I didn't see in the archives. The plans say to peel >ply the edges of the aft face ply. Is this just the left and right edges or >does this include the angled bottom edge too? If so, why don't the plans >mention anythings about peel plying the angled top edge. The top, bottom and sides get glued into the fuselage. Actually you end up adding a shoulder support to the top, but a little sanding takes care of the necessary scuffing. > >5) On F-22 the plans say to press the doubler into place on the wet layup. >The plans don't mention to micro the face of the double first as is >indicated as a standard practice in chapter 3. The plans do state to micro >the aft face of the doubler before glassing it though. Should I micro the >forward face of the doubler before pressing it into place? Yes, foam gets microed. > >6) After glassing the aft face of F-22 the plans say to weight bulkhead flat >for cure. It then says to use peel ply and wax paper. Should the whole >face be peel plyed or just the overlap of the UND from the doubler? I peel plyed the whole thing. It was easier. > >7) Is the whole aft face of the IP peel plyed or just the area above the leg >holes? Same as 6 for me. > >8) There is no cross section of the vertical ribs on the forward face of the >IP. Do these have channels as well? Seems like they wouldn't but I'm not >sure. What did you do? I didn't put channels on. > >9) Picture of firewall on page 4 shows different cutout location for >electrical than is shown on drawing M-3. I know not to cutout the holes >until assembly but which is right - the picture or the drawing? I don't have the information in front of me, but I always use the drawings as the authority. > >10) The plans say to do some sanding on the IP to prepare for the rib >installation. Wouldn't it be easier to peel ply where the ribs will go >instead? Is this acceptable? Sanding is also easy. > >11) Same issue with landing gear bulk hard points. Should the hard points >be peel plyed instead of sanding after installtion into bulkheads? As above. > >12) Plans say to micro forward surface of landing gear bulkhead (as >expected). I just want to confirm that this doesn't include the hard points >(since chapter 3 says not to micro between two layers of glass). Correct. > >13) Any advice on cutting square holes like those on the firewall? I used a drill and a flat file. > >I think I'm in trouble. No you're not. Just beginning that's all. When it gets to the point that you are happy trimming the foam by biting the edges off with your teeth, then you will know that you have really got comfortable with the medium :-) Regards, Peter Militch #740 Chapt 7/8 From: "John Slade" Subject: Re: COZY: Novice Chapter 4 Questions Date: Fri, 29 Oct 1999 10:26:53 -0400 Rick, >I'm being a good boy and studying the plans in detail in preparation for >building. This is when I started asking similar questions. Its a frustrating time. You'll find that most of your questions are answered when you actually DO stuff. Here's my 2c on your questions... >1) Chapter 4, page 1, figure 6. I read all about how the diagrams aren't >perfect with regard to sizes but... This figure shows several fractions Don't sweat the details. No, I think its the instrument panel that tends to come up a bit short. A 1/4 inch extra there wouldn't hurt. Probably not necesssary, but if you'd like to build the seat a little longer, go ahead. You can always trim it later. Its easier to trim than to add length. - but most build it per the drawings and fit it with no problem. >2) angled bottom meet? Do the cut out corners help? It's probably obvious if >I was doing it but I can't yet. Works fine. When you do it you'll figure it out. Tough to visualize some of these things.... but I know - you have nothing else to do right now. >3) I read that you don't cover the cutouts of the bulkheads but I just want >to confirm this on the seatback since it is the only bulkhead that have the >sides glassed. Is the end result of the seatback as if the corners where >cut out after all the glass was applied? I think this is in the archives. Some discussion about wether to glass the sides of the seatback or not. The part is taped in place with 2 BID tape along all joins, so glassing the sides is not really relevant. Many don't bother. I suspect some of the instructions in the early stages are there to teach you things rather than to achieve a particular structural purpose. Best way is to just do what the plans say, even if it sounds a bit pointless. At the least you'll learn not to do that next time, but it won't stop your airplane from flying. What WILL stop your airplane from flying is sweating all the details and figuring out how to change lots of things to the extent that you never finish it. Not kidding. This is probably the main reason many airplane projects don't get finished. Personally, I don't want to invest thousands of hours into a project with no end result, so I usually just do what it says and move on. >4) A peel ply question I didn't see in the archives. The plans say to peel >ply the edges of the aft face ply. Is this just the left and right edges or >does this include the angled bottom edge too? Chaper 3 tells you when to peel ply. The idea is that you need a good bonding surface if more glass is going to go there, so yes, peel ply all the edges. Note that the plans tell you something once, then sometimes skip telling you the same thing again. Plans would be three times as big if everything was said every time. You're supposed to learn the standard rules as you go along. >5) On F-22 the plans say to press the doubler into place on the wet layup. >The plans don't mention to micro the face of the double first as is See above. Chap 3 gives you the rules for glass to glass, glass to foam, foam to foam bonding. >6) Should the whole face be peel plyed Some peel ply everything. Others say this adds weight. I've started using 4mm plastic on top of the layup and / or peel ply. (see analysis of results on my web page http://kgarden.com/cozy/chap19.htm ) . As with the seat back - you need to peel ply where there will be a glass bond. >7) Is the whole aft face of the IP peel plyed or just the area above the leg holes? See above >8) There is no cross section of the vertical ribs on the forward face of the >IP. Do these have channels as well? I think plans show a vertical rib, same as the horizontal, either side of the central support. Adds structure and you need somewhere to run wires. >9) Picture of firewall on page 4 shows different cutout location for >electrical than is shown on drawing M-3. Sketches in plans are often just to give you an idea what something looks like. Not to scale. Use the drawings. >10) The plans say to do some sanding on the IP to prepare for the rib >installation. Wouldn't it be easier to peel ply where the ribs will go >instead? Is this acceptable? Sure. But plans often suggest that you rough up the surface even if you peel plyed. >11) Same issue with landing gear bulk hard points. Should the hard points >be peel plyed instead of sanding after installtion into bulkheads? Both, but don't sand into the fibers. >12) Plans say to micro forward surface of landing gear bulkhead (as >expected). I just want to confirm that this doesn't include the hard points >(since chapter 3 says not to micro between two layers of glass). Correct. >13) Any advice on cutting square holes like those on the firewall? Drill, then jig saw >14) Last one - I read all the debates on peel ply (only where needed vs. See notes above. >I think I'm in trouble. This many questions for such a simple chapter. No. You're just doing what I did while waiting for materials. Relax. Just read read read. If it doesnt seem to make sense, suspect you're understanding first and the plans being wrong last. Reread, get the big picture by looking at the drawings and subsequent chapters, then reread again. Takes a while to get your head around some of the stuff, but it usually comes clear eventually. >I'm one of those people who measure everything to the nearest 64th of an inch. Stop this immediately! We airplane builders measure in decimal ( to nearest 1/100th) :) Was once said - measure with a micrometer, mark with a ruler, cut with a chainsaw. >I'm sure many of you have gone through this. Oh yea! >Off to tear apart chapter 5 while I wait for all your wisdom to these >questions. Don't read the chapters one by one in great detail. Read the entire plans, then the study the drawings. Then read the chapers in detail as you come to them jumping forward to see how things will be used or fitted in later chapters. This should give you the big picture (while also keeping you quiet for a few weeks till your materials arrive). Regards, John Slade Cozy MKIV #757 (glassing wings) From: "John Slade" Subject: Re: COZY: Novice Chapter 4 Questions Date: Fri, 29 Oct 1999 13:07:10 -0400 Rick, I misdirected you in my previous post. My "plastic peel ply experiment" is detailed in http://kgarden.com/cozy/chap20.htm Note that my web page starts with the immortal words: "This is just my opinion. I could be wrong. " John Slade Cozy #757 From: Wayne Hicks Subject: RE: COZY: Novice Chapter 4 Questions Date: Fri, 29 Oct 1999 14:28:26 -0400 Rick Maddy asked these questions. Wayne Hicks responds: 1) Maybe (the seatback) needs to be 29.0". ---------> many new builders try to make the math work here. :-) When installing the seatback in Chapter 6, don't worry about getting it exactly at 45 degrees, just make sure the top is flush with the upper longerons, the bottom flush with the bottom. Your back won't be able to tell the difference between 47 and 45 degrees, especially with seat cushions. 2) how well does (BID) glass sit where the sides and angled bottom meet? --------> 1 ply of BID will conform to almost any complex curve, so don't worry. 3) I read that you don't cover the cutouts of the bulkheads but I just want to confirm this. --------> It would be a pain in the butt to do flox corners on the cutouts. Plus, you'll flox and 2-BID tape the seatback to the fuselage in Chapter 6. You'll end up with lots of strength. 4) A peel ply question (snip) --------> Peel plying the bottom edge is a good idea even if it's not mentioned in the plans. If you want to PP on the top :-) , take a look at Chapter 8 to determine the area where future glass layups for the shoulder brace will go. 5) On F-22 the plans say to press the doubler into place on the wet layup. The plans don't mention to micro the face of the double first as is indicated as a standard practice in chapter 3. ---------> Better ask Nat. I just followed the plans. 6) After glassing the aft face of F-22, the plans say to use peel ply and wax paper. ---------> Look at figure 10. Put PP there where the next reinforcing layups will go. Put wax paper (better to use plastic) under the weights to keep them from sticking to the bulkheads. 7) Is the whole aft face of the IP peel plyed or just the area above the leg holes? --------> the plans say just the leg holes 'cause you'll be glassing other stuff there later on. But PP on the whole thing if you want a nice cosmetic finish to the IP. Skip it if you intend to use an overlay of some type. 8) There is no cross section of the vertical ribs on the forward face of the IP. --------> I assumed we made them all like shown in Figure 13, so I included channels on all ribs. 9) Picture of firewall on page 4... which is right - the picture or the M-3 drawing? --------> Ask Nat, but I'd go by the M drawings. Just my guess, but some of the pictures from the plans may be of the prototype. Maybe not. 10) The plans say to do some sanding on the IP to prepare for the rib installation. Wouldn't it be easier to peel ply where the ribs will go instead? Is this acceptable? ----------> Yes. You catch on quick! Sure you haven't done this before? 11) Same issue with landing gear bulk hard points. Should the hard points be peel plyed instead of sanding after installtion into bulkheads? --------> That's what I did was to start the hardpoint layups on a piece of peel-ply and finish off the final layer with peel ply. But remember, there's nothing wrong with sanding an area for next glass application. PP is just more convenient, and some say it provides a better bond surface. I STILL lightly sand all peel ply areas to knock off the shine so as to get good chemical bonding. (Topic covered will in the recent Ron Alexander articles in Sport Aviation.) 12) I just want to confirm that this doesn't include the hard points (since chapter 3 says not to micro between two layers of glass). ---------> Correct. I shall not micro between glass. 13) Any advice on cutting square holes like those on the firewall? ---------> Mark the square. Draw lines through opposite corners to find the center. Use a hole saw to cut most of it out. Use a coping saw or hand hold a hack saw blade to cut out the corners. 14) Last one - I read all the debates on peel ply --------> The REAL danger with PP'ing on everything is FORGETTING to remove the peel ply between layups. Forget on a critical part and you'll not only PP on yourself, but all over everything else too as you watch your airframe fall apart around you. I think I'm in trouble. This many questions for such a simple chapter. --------> Rick, you're not the only one, you're just one of the less timid souls to have asked! I'm one of those people who measure everything to the nearest 64th of an inch. Heck, I was measuring drywall to the nearest 16th of an inch for my garage and got mad when there was an 1/8" gap! --------> Then we should expect to see your plane as the Oshkosk Grand Champion is 4 years or so? ___________________________________ Wayne Hicks Cozy IV #678 Chapter 18 http://www.geocities.com/yosemite/falls/2027 From: "Capps Family" Subject: COZY: Seat:Size and Angle Date: Fri, 29 Oct 1999 07:49:51 -0500 - Rick Maddy Wrote - SNIP" 1) Chapter 4, page 1, figure 6. I read all about how the diagrams aren't perfect with regard to sizes but... This figure shows several fractions that add up to 28.0". Chapter 4 page 1, figures 1 & 2 show the foam as 28.8" - 0.75" for angle = 28.05". I know 0.05" isn't much and I wouldn't bring it up except someone sent me an email indicating that several builders had trouble with the seatback being too short. Maybe it needs to be 29.0". Anyone experience this? SNIP" ================================================== Front Seat Back Size & Angle (Brace) As stated in the plans the front seat back shall be "inclined at approx. 45 deg". Well being one who can't sleep at night knowing something isn't exact, I whipped out my trusty CAD program and laid out the Fuselage side as shown on (Chap 5 - page 3, fig 5), then I positioned the seat back as called for on (Chap 6 - page 1, fig 3). Also included, is the dimensions needed for the Front Seat Back Brace, as called out on (Chap 6 - page 4, fig 15) Findings for Front Seat Back: Angle = 47.35 ( using Nat's 60 x 40 method, which I think greatly simplifies things). Length = 28.92 (point to point, Total length needed). Brace = 18.5 (height) x 17.04 (base) x 25.15 (hypotenuse) note: do to the fact that the fuselage bottom in the area of the brace is not level, the brace bottom is .09" to wide along it's (base), furthest from the seat back. I must say, I have thoroughly studied the plans, and am greatly impressed with the quality and tolerances provide. One thing that makes building my Cozy even more sweeter, is this forum, and the ability to have access to the archives. My hats off to Nat Puffer for designing such of skillful piece of engineering. For those of you who would like a technical drawing illustrating the above, I would be happy to forward one to you via email. Blue Skies; Larry Larry A. Capps #829 cappsfan@ameritech.net Naperville, IL From: "Rick Maddy" Subject: COZY: Front Seatback Corner Cutout Dimensions Date: Thu, 4 Nov 1999 22:10:35 -0700 I need a sanity check here. I was studying the plans and diagrams for the first few chapters and ran across a big discrepancy in the dimensions for the top cutouts in the front seatback. If you look at chapter 5, page 3, figure 7, section CC you will see a block of foam that is 2.5" high, 0.75" wide, and 1.4" high on the inside. If you add the upper longeron and stiffener you get an additional rectangle that is 0.75" wide and 1.4" high. Now imagine the seatback intersecting all this at a 45 degree angle. The 2.5" dimension becomes 3.54". The 1.4" dimension becomes 1.98". Now if you go to large drawing M-1 and measure the top cutout for the seatback you will get much different dimensions. I get about 3.1" and 2.05" respectively. This is a difference of -0.44" and +0.07" respectively. The latter isn't much but the former is. Am I missing something here? Am I too anal? I can see the cutout being too big to take into account fiberglass, epoxy, and flox but the 3.1" dimension is too small. Rick Maddy (cozy@maddyhome.com) Cozy Mk IV #0824: Pre-build (www.maddyhome.com/cozy) From: jhocut@mindspring.com Date: Fri, 05 Nov 1999 07:41:20 -0500 Subject: Re: COZY: Front Seatback Corner Cutout Dimensions It's been so long since I've built the seatback and fuselage I can't remember exact dimensions, but I do know that I just did what the plans said, with maybe a little minor adjusting with a sanding block here and there, and everything worked out fine. Jim Hocut Cozy IV #448 - ch 19 From: "John Slade" Subject: Re: COZY: Front Seatback Corner Cutout Dimensions Date: Fri, 5 Nov 1999 08:17:41 -0500 >I was studying the plans and diagrams for the >first few chapters and ran across a big discrepancy in the dimensions for >the top cutouts in the front seatback. Rick, When are your materials scheduled for delivery??? Could you call Wicks and request urgent handling? Perhaps we builders could club together and help pay for Fedex shipping :) >I need a sanity check here. No. You need zanex. :) Am I too anal? Since you asked... Yes. Make the seatback per the M drawings. If it doesnt fit... make it fit. Chances are your fuselage will not be exactly per plans size. I didnt try to follow your calculations. Don't have time... I have an airplane to build. If you think your calculations are right, make it bigger. You can always trim it later. Chances are that you're missing something and the M drawing size is right. My input would be to stop wasting you're time checking things like this. This project is complex enough without coming at everything from three directions. As you move deeper into the project the calculations will get much harder. Keep in mind that just about anything that's wrong can be fixed. Making a few mistakes (and you will) is MUCH better than being perfect and never getting anything done. Regards, John Slade Date: Fri, 05 Nov 1999 08:00:17 -0600 From: David Domeier Subject: Re: COZY: Front Seatback Corner Cutout Dimensions Rick, It's been some time since I built the fuselage so I do not recall much about it, but I can say that this was not a problem. I'd remember that. In looking at the plan, it would appear that CC begins aft of where the seat back joins the fuselage. The BB section is where the seat back joins the side. Do it per the plan, it will work out. After all these years,there are not many errors left in it. We harassed Nat alot in the beginning over stuff like this. dd From: "RICH LETO" Subject: COZY: peel ply Date: Thu, 4 Nov 1999 18:36:59 -0700 I finished the seatback bulkhead, but forgot to peel ply the edges, is it too late to peel ply now that it is dry? any tips would be appreciated. rich leto From: cdenk@ix.netcom.com Date: Thu, 4 Nov 1999 21:38:18 -0500 (EST) Subject: Re: COZY: peel ply I understand it's possible to add epoxy, and fiberglass or peal ply up to the point of knife trim. Probably OK for some non structural situations. But the instruction's comments, to sand with 80 grit after cure. Sand only enough to remove the sheen, with minimum of fiberglass removed. I would just sand, and not worry about it. From: "Paul Kuntz" Subject: Re: COZY: Front seat back. Date: Sun, 21 Nov 1999 16:27:39 -0800 I noted an earlier incorrect reply to this question. Refer to Figure 5 at the bottom of Chapter 4 Page 1. It clearly shows in Section A-A, and in the explanatory text, that the bid cloth on the back side of the seat back wraps down over the sides so that it joins the front side layup on the sides as well as at the top and bottom edges of the seat back, with flox corners all around. The seat back is the only bulkhead made this way, however. The rest of the bulkheads will have bare foam edges. Paul Kuntz Cozy MK IV England My question revolves >around glassing the rear surface. As I understand it the rear lay up will lay >down each 45 degree end where it will meet the front lay up at a flox edge. >What about the sides? Does the rear lay up fold down each side and therefore >meet the front again at a flox? > Date: Tue, 23 Nov 1999 13:19:20 -0500 From: John Subject: Re: COZY: Front seat back. Paul and new builders, I built my front-seatback in the same way as Paul is saying. I also was confused and asked for clarification on the list. All of the rigtht information IS there in the plans. The section A-A diagram (The one in the extreme lower right corner of the page) is an edge view and is how the finished piece will look when viewed on edge from the bottom or the top, just like in the picture. The finnished piece is a nicely rigid (completely enclosed) cocoon of fiberglass. I waited until after cure to cut any cutouts. I haven't really seen any significant reason that the edges of this bulkhead is done differently than the others, however, I found that it was a good reason to break out the router and put a nice radiused edge on the seat-back.Good practice with foam shaping that will come in handy later. The back-side fiberglass wraps nicely around the edges and meet at the front edge with a nice strong floxed 90 degree corner as is shown on chapter 3, page 11, flox corner sequence 4. I would bet that most builders have not put the rounded sides because of either the same confusion or the decision that the difference is not an important point. Having fun with my Star-Wars interior design, John A. Millington Plans # 706 Paul Kuntz wrote: > I noted an earlier incorrect reply to this question. Refer to Figure 5 at > the bottom of Chapter 4 Page 1. It clearly shows in Section A-A, and in the > explanatory text, that the bid cloth on the back side of the seat back wraps From: JERSKIP@aol.com Date: Tue, 30 Nov 1999 08:18:48 EST Subject: COZY: Firewall Bulkhead Stupid question, but I haven't had one in a while, so I guess I'm entitled. The plans say use 1/4" fir for the temporary firewall. Home Depot said they don't stock it. Is plain old 1/4" plywood OK, or do I need to keep hunting? Thanx, Jerry Schneider #768 Finishing Bulkheads From: "John Slade" Subject: Re: COZY: Firewall Bulkhead Date: Tue, 30 Nov 1999 09:23:10 -0500 Jerry, >The plans say use 1/4" fir for the temporary firewall. Home Depot said they >don't stock it. Is plain old 1/4" plywood OK, or do I need to keep hunting? I used plain old home depot 1/4 plywood for the temp firewall. Just be sure its not warped. Regards, John Slade, Cozy #757 http://kgarden.com/cozy From: cdenk@ix.netcom.com Date: Tue, 30 Nov 1999 19:33:28 -0500 (EST) Subject: Re: COZY: Firewall Bulkhead I believe the instructions call for aircraft plywood, which is probably close to marine plywood, without the quality control of usual aircraft materials. The proper plywood in my eyes would have these requirements: a: Waterproof glue b: All plys (interior and face) to be high quality wood, with fairly straight grain, and no voids (space between pieces in one ply or knot holes. c: The grain should not be coarse. d: A grade stamp or other certification that it meets some standard. This gets a little gray, without knowing the specifics of the stated grade, its difficult to know what is good and bad. The most common plywood grading organization is the American Plywood Association (APA). Most people are familiar with the grade "CDX" which approximately says there are small (1" dia.)unfilled knot holes on one face, and filled on the other. Neither face is sanded, or what one would consider an good appearance grade. The "X" is exterior exposure glue. This does not assure acceptable performance for continued exterior exposure. It will resist a few rains during the construction, but the interior voids will trap moisture, with deterioration. Having said all that, the EZ firewall is a major structural member, taking loads from the spar, engine mount items, and landing gear, and distributing them to the fuselage, strakes, etc. We are talking exactly one piece of material, which for most of us (At least those in the US and Canada) is readily available without terrible cost, and would recommend using the aircraft quality. Marine grade plywood does have waterproof (I didn't say water resistant) glue, and no internal voids, which probably qualify it for consideration. The quality control one needs to do, is: From the scraps cut off and out, examine for no voids, and a good glue line. The glue line can be checked by pealing, breaking at the glue line. The wood should break first. Even a small defect should be reason to strap, since it could be worst elseware. Date: Tue, 30 Nov 1999 20:08:47 -0500 From: Jeff Russell Subject: Re: COZY: Firewall Bulkhead cdenk@ix.netcom.com wrote: > > I believe the instructions call for aircraft plywood, > Having said all that, the EZ firewall is a major structural member, > taking loads from the spar, engine mount items, and > landing gear, and distributing them to the fuselage, strakes, etc. I think the question was about the false firewall and not the real one? What about the firewall that the Berkut people use. It is out of 18 Lb urethane foam with alum hardpoints for the engine mount? It has no plywood at all. -- Jeff From: Roy Grossinger Subject: RE: COZY: Firewall Bulkhead Date: Wed, 1 Dec 1999 09:46:24 -0800 While still in college we made a firewall out of Urethane foam too, using G-10 for hard points and firewall passthroughs. But that was a tail dragger, no loads other then the engine and battery. As long as your material has properties to handle the environment and loads you can make the firewall out of just about anything. ROY cdenk@ix.netcom.com wrote: > > I believe the instructions call for aircraft plywood, > Having said all that, the EZ firewall is a major structural member, > taking loads from the spar, engine mount items, and > landing gear, and distributing them to the fuselage, strakes, etc. I think the question was about the false firewall and not the real one? What about the firewall that the Berkut people use. It is out of 18 Lb urethane foam with alum hardpoints for the engine mount? It has no plywood at all. -- Jeff From: cdenk@ix.netcom.com Date: Wed, 1 Dec 1999 17:34:06 -0500 (EST) Subject: Re: COZY: Firewall Bulkhead Jeff wrote >What about the firewall that the Berkut people use. It is out of >18 Lb urethane foam with alum hardpoints for the engine mount? I was referring to EZ's, the Berkut is a different aircraft in many ways. One must rely upon the competence or lack of.., and make a decision whether the entire package is safe. And this is not any reflection on Berkut, but a much more general statement. From: "Barry Gardner" Subject: Re: COZY: Firewall Bulkhead Date: Wed, 1 Dec 1999 20:36:22 -0600 As an ex-employee of International Paper Company, I'm aware that there is more to plywood than "plain old 1/4". See: http://www.fpl.fs.fed.us/pdcomp/handbook/plywood.htm#t3 to learn more than you probably wanted to know about the grades, types, and engineering characteristics of plywood. The better grades have limits on internal voids, which considerably weaken the strength of plywood. That's not to say that some of the commonly available lesser grades wouldn't work for our application but rather to point out that some plywood grades are definitely better than others. Barry Gardner Wheaton, IL ----- Original Message ----- From: To: ; ; Sent: Wednesday, December 01, 1999 7:01 PM Subject: Re: COZY: Firewall Bulkhead > > In a message dated 11/30/99 8:33:56 AM, JERSKIP@aol.com wrote: > > >Is plain old 1/4" plywood OK, or do I need to keep hunting? > > Yes it is. That's what I used. I was under the impression that plain old > plywood was made from fir. > > Regards > From: "fmooers" Subject: Re: COZY: Firewall Bulkhead Date: Thu, 2 Dec 1999 19:43:59 -0800 1/4" plywood is 3 to 5 plys. Typically a soft wood like pine, doug fir, etc. Using hard wood, the plywood is usually for finishes, cabinets, paneling, etc. Imports are usually soft hard woods for either finishes or cabinetry. The grading tells the type of face, core and backing materials. the rating for exterior or interior will be based upon the type of adhesives used for adhering the plys. The flooring business (my business) has a 5 ply white Russian Birch, 1/4''x 4'x8', it uses a phenolic resin, has passed boil tests for delamination, all plys are void free. We have sold millions of square feet with minimal complaints maybe a couple dozen annually. This product is used under vinal floors in kitchens and baths. This a specialized product and typically you will not find this product at a Home Depot or equivilant. If anyone should like to explore this product, please feel free to contact me. Fred Mooers (visinry@itis.com) Madison, WI ----- Original Message ----- From: Barry Gardner To: ; ; ; Sent: Wednesday, December 01, 1999 6:36 PM Subject: Re: COZY: Firewall Bulkhead > As an ex-employee of International Paper Company, I'm aware that > there is more to plywood than "plain old 1/4". See: > > http://www.fpl.fs.fed.us/pdcomp/handbook/plywood.htm#t3 > > to learn more than you probably wanted to know about the grades, > types, and engineering characteristics of plywood. The better > grades have limits on internal voids, which considerably weaken > the strength of plywood. That's not to say that some of the > commonly available lesser grades wouldn't work for our > application but rather to point out that some plywood grades are > definitely better than others. > > Barry Gardner > Wheaton, IL > > ----- Original Message ----- > From: > To: ; ; > > Sent: Wednesday, December 01, 1999 7:01 PM > Subject: Re: COZY: Firewall Bulkhead > > > > > > In a message dated 11/30/99 8:33:56 AM, JERSKIP@aol.com wrote: > > > > >Is plain old 1/4" plywood OK, or do I need to keep hunting? > > > > Yes it is. That's what I used. I was under the impression that > plain old > > plywood was made from fir. > > > > Regards > > > > From: "fmooers" Subject: Re: COZY: Firewall Bulkhead Date: Thu, 2 Dec 1999 19:43:59 -0800 1/4" plywood is 3 to 5 plys. Typically a soft wood like pine, doug fir, etc. Using hard wood, the plywood is usually for finishes, cabinets, paneling, etc. Imports are usually soft hard woods for either finishes or cabinetry. The grading tells the type of face, core and backing materials. the rating for exterior or interior will be based upon the type of adhesives used for adhering the plys. The flooring business (my business) has a 5 ply white Russian Birch, 1/4''x 4'x8', it uses a phenolic resin, has passed boil tests for delamination, all plys are void free. We have sold millions of square feet with minimal complaints maybe a couple dozen annually. This product is used under vinal floors in kitchens and baths. This a specialized product and typically you will not find this product at a Home Depot or equivilant. If anyone should like to explore this product, please feel free to contact me. Fred Mooers (visinry@itis.com) Madison, WI ----- Original Message ----- From: Barry Gardner To: ; ; ; Sent: Wednesday, December 01, 1999 6:36 PM Subject: Re: COZY: Firewall Bulkhead > As an ex-employee of International Paper Company, I'm aware that > there is more to plywood than "plain old 1/4". See: > > http://www.fpl.fs.fed.us/pdcomp/handbook/plywood.htm#t3 > > to learn more than you probably wanted to know about the grades, > types, and engineering characteristics of plywood. The better > grades have limits on internal voids, which considerably weaken > the strength of plywood. That's not to say that some of the > commonly available lesser grades wouldn't work for our > application but rather to point out that some plywood grades are > definitely better than others. > > Barry Gardner > Wheaton, IL > > ----- Original Message ----- > From: > To: ; ; > > Sent: Wednesday, December 01, 1999 7:01 PM > Subject: Re: COZY: Firewall Bulkhead > > > > > > In a message dated 11/30/99 8:33:56 AM, JERSKIP@aol.com wrote: > > > > >Is plain old 1/4" plywood OK, or do I need to keep hunting? > > > > Yes it is. That's what I used. I was under the impression that > plain old > > plywood was made from fir. > > > > Regards > > > > From: "John Slade" Subject: Re: COZY: temporary Firewall Bulkhead Date: Sun, 28 Nov 1999 22:11:00 -0500 >As an ex-employee of International Paper Company, I'm aware that >there is more to plywood than "plain old 1/4". Yea, but we're talking about the TEMPORARY firewall. All it does is hold the longerons in place while you're assembling the tub. It gets thrown away after Chapter 7! Regards, John Slade From: Roy Grossinger Subject: RE: COZY: temporary Firewall Bulkhead Date: Thu, 2 Dec 1999 07:12:55 -0800 I beg to differ. I never throw away good wood you can use for sanding blocks, stiffeners for jigs, jigs.... Keep them scraps :-) Lets say the temporary firewall gets converted. Subject: Re: COZY: temporary Firewall Bulkhead >As an ex-employee of International Paper Company, I'm aware that >there is more to plywood than "plain old 1/4". Yea, but we're talking about the TEMPORARY firewall. All it does is hold the longerons in place while you're assembling the tub. It gets thrown away after Chapter 7! Regards, John Slade From: "John Slade" Subject: Re: COZY: temporary Firewall Bulkhead Date: Thu, 2 Dec 1999 11:08:26 -0500 >I never throw away good wood you can use for sanding >blocks, stiffeners for jigs, jigs.... Keep them scraps :-) Lets say the >temporary firewall gets converted. Absolutely. I have a large area under my workbench for "used" wood. John Slade From: "dewayne morgan" Subject: COZY: chapter 4 firewall template Date: Fri, 10 Dec 1999 13:59:30 -0500 builders, Everyone has said to stay on the lines and that will get you into chapter 6 but the templates for the temporary firewall bulkhead is about 1/8 to 1/4 inch out of alignment at the centerline from top to bottom. are there any other dimensions available that i can use for reference other than the 3.1 x 7.5 dimension at the bottom? Or is the temporary one that critical in the first place. thanks dewayne From: "Russ Fisher" Subject: Re: COZY: G-10 HARDPOINTS Date: Sun, 19 Dec 1999 07:49:46 -0500 David, If you live near a metropolitan area, most any plastics supply house should carry it. The first one I called in Rochester, NY stocked it and had a piece about 12" x 15" in their scrap bin, which saved me cutting charges. This was enough for my landing gear bulkhead hardpoints. I paid about $15 for it. Be sure to use carbide to cut it. I used a carbide blade in my tablesaw for the major cuts and a carbide coated jigsaw blade (available at any home center) for the detail cuts. If you can't find it locally, the place I obtained it from is Cadillac Plastic 1328 University Ave. Rochester, NY (zip is not in phone book) (716) 442-6690 Russ Fisher >Could someone send me the phone/address of the individual that >had a G-10 hardpoint source? Thanks >David Burkes #837 Chpt. 4