From: "James E. Marker" Subject: COZY: Q: Forward Face of F-22 Date: Sun, 19 Jan 1997 21:02:59 -0500 The forward face of F-22 should be layed up as follows, right? UNI - Local BID - Local UNI - Local BID - Local UNI - Local BID - Local UNI - Local BID - Local UNI - Local BID - Overall BID - Overall UNI - Above Leg Holes The plans seem to say lay up BID-Overall then UNI-Above Leg holes then UNI/BID local pieces, but figure 10 chapter 4 seems to imply the above. Which is correct? The above seems to make more sense. Does it really matter? P.S. I am very worried about making errors that cost me time. I didn't see this in the 1996 archives. ============================================================================ ================= Jim Marker Email: jemstone@csra.net Web: http://www.csra.net/jemstone/ Cozy Mark IV #0581 Cozy Web Page: http://www.csra.net/jemstone/cozy.htm From: Marc J. Zeitlin Subject: COZY: Q: Forward Face of F-22 (fwd) Date: Mon, 20 Jan 97 9:26:32 EST Jim Marker writes: >The forward face of F-22 should be layed up as follows, right? >. >. >The plans seem to say lay up BID-Overall then UNI-Above Leg holes then >UNI/BID local pieces, but figure 10 chapter 4 seems to imply the above. >Which is correct? The above seems to make more sense. Does it really >matter? I don't have the plans in front of me, but in almost every case I've run into both on the Q2 and on the COZY, you lay up the overall layers of glass first, and then do the local ones. The reason for this (as far as I can determine, having tried the other way once or twice) is that if you try to lay up a large piece of glass over a small piece, you tend to get air bubbles at the ends of the smaller piece under the larger ones. You don't get this when going from large to small. So, I'd follow the text of the plans in this case. >P.S. I am very worried about making errors that cost me time. I didn't >see this in the 1996 archives. Jim, don't worry about errors that cost time. Worry about errors that cost safety. -- Marc J. Zeitlin Email: marcz@an.hp.com From: "James E. Marker" Subject: COZY: Q: Chapter 4 - Instrument Panel Ribs Date: Thu, 23 Jan 1997 09:13:40 -0500 Questions about the instrument panel ribs: 1. Should the fillets be floxed? 2. Should the forward glass to glass corner be a flox corner? ============================================================================ ======= Jim Marker Email: jemstone@csra.net Web: http://www.csra.net/jemstone/ Cozy Mark IV #0581 Cozy Web Page: http://www.csra.net/jemstone/cozy.htm From: Marc J. Zeitlin Subject: COZY: Q: Chapter 4 - Instrument Panel Ribs (fwd) Date: Thu, 23 Jan 97 9:49:47 EST Jim Marker writes; >Questions about the instrument panel ribs: > >1. Should the fillets be floxed? Dry micro is fine - in a case like this, the fillet is just to allow the glass to conform - not for bending strength. >2. Should the forward glass to glass corner be a flox corner? Not sure which corner you're referring to here, but I don't remember any flox corners on any of the bulkheads. Nat's pretty good about calling out flox corners when they're needed - if the plans don't call for one (especially in the early chapters when he pretty much tells you when to breath in and out as well :-) ) you don't need it. If you need a radius in a corner, use micro unless told otherwise. -- Marc J. Zeitlin Email: marcz@an.hp.com Date: Thu, 23 Jan 1997 08:18:14 -0700 (MST) From: Ron Lee Subject: Re: COZY: Q: Chapter 4 - Instrument Panel Ribs (fwd) Another way to think about when FLOX is needed is if the layups glass to glass contact is only a narrow line...as in a corner, in that case a flox corner is needed. When you overlap glass an inch or more, you just put the dry micro in to make the bend work...As Marc describes below. Ron Lee At 09:49 97/1/23 EST, you wrote: >Jim Marker writes; > >>Questions about the instrument panel ribs: >> >>1. Should the fillets be floxed? > >Dry micro is fine - in a case like this, the fillet is just to allow the >glass to conform - not for bending strength. > >>2. Should the forward glass to glass corner be a flox corner? > >Not sure which corner you're referring to here, but I don't remember any >flox corners on any of the bulkheads. Nat's pretty good about calling >out flox corners when they're needed - if the plans don't call for one >(especially in the early chapters when he pretty much tells you when to >breath in and out as well :-) ) you don't need it. > >If you need a radius in a corner, use micro unless told otherwise. > >-- >Marc J. Zeitlin Email: marcz@an.hp.com > > From: "James E. Marker" Subject: COZY: Autocad Instrument Panel Drawing (U) Date: Sat, 25 Jan 1997 15:32:34 -0500 I printed out all the Autocad drawings from Marc's excellent web page, and they are all perfect, except the insrument panel is about 1/2" narrow. All the edges agree perfectly, but the centerline is about 1/4" on each side too narrow perfectly symmetrical. Has anyone else built from these. I have to assume the template from Nat is correct. Was this narrower panel an improvement that someone found out worked better? I really liked being able to cut these out an save tracing, etc. Anymore of these around? Jim... P.S. I printed a 1 x 1 inch square and it was perfect. I also printed a 36 x 36 and it was perfect so I feel confident the plotter is calibrated correctly. ============================================================================ ======= Jim Marker Email: jemstone@csra.net Web: http://www.csra.net/jemstone/ Cozy Mark IV #0581 Cozy Web Page: http://www.csra.net/jemstone/cozy.htm Date: Mon, 27 Jan 1997 08:44:22 -0500 From: william l kleb Organization: NASA Langley Research Center Subject: Re: COZY: Autocad Instrument Panel Drawing (U) James E. Marker wrote: > except the insrument panel is about 1/2" narrow. hmmm...i don't recall this problem. if this is the case, i would just make them plans width, otherwise when assembling the sides in chapter six you'll have to use much more than strapping tape to clamp the sides together... > Has anyone else built from these. i built F22, F28, the IP, and the seatback from these. everything worked fine. (thanks lee d and marc z!) bil From: Lee Devlin Subject: Re: COZY: Autocad Instrument Panel Drawing (U) Date: Mon, 27 Jan 1997 9:23:06 MST > > I printed out all the Autocad drawings from Marc's excellent web page, and > they are all perfect, except the insrument panel is about 1/2" narrow. All > the edges agree perfectly, but the centerline is about 1/4" on each side > too narrow perfectly symmetrical. > > Has anyone else built from these. I have to assume the template from Nat > is correct. Was this narrower panel an improvement that someone found out > worked better? > > I really liked being able to cut these out an save tracing, etc. Anymore > of these around? > > Jim... > > P.S. I printed a 1 x 1 inch square and it was perfect. I also printed a > 36 x 36 and it was perfect so I feel confident the plotter is calibrated > correctly. I created the templates and built from them and did not find this problem. I went out to the garage (after recovering from a minor heart attack!) and measured the fuselage spacing at that point and came up with 39.25". I then measured the Nat's templates and found that each is 19.625" wide and so the panel agrees with Nat's templates. I haven't had a chance to bring up the template on my CAD system, but I'll do so at the first opportunity. Try using a 'measure' command on your CAD system and see where the error occurs , i.e. in the .dxf file or on the plotter. I'm encouraged you are _checking_ to see if any errors crept into the CAD/.dxf/plot transformations. This will prevent a lot of heartache later on. You might also want to plot out a 39.5" square to see if some compressing is being done by your drivers to get all of the template on the paper. Lee Devlin Date: Tue, 15 Apr 1997 15:05:13 -0700 From: robert mancuso Subject: COZY: forward landing gear bulkhead I made a major Boo Boo !!! I made the forward landing gear bulkhead too short. I dont' know if I should cut it in half and add the 3/8" and reinforce with fiberglass or should I add some extra flox on the sides or scrsp it and start over.. I would like to salvage the piece if at all possible.. I would appreciate any knowledge or wisdom anyone can throw my way .. Thank you Robert Mancuso #537 From: "Steve Campbell" Subject: RE: COZY: chapter 4,front seatback Date: Tue, 13 May 1997 10:40:10 On Tue, 13 May 1997 10:13:17 -0500, tpierce@ghg.net wrote... >In chapter 4 on the front seatback, the back side calls for 1 ply of BID >at 45 degrees. Being 42 inches wide, I had to add a small triangular >piece of bid to finish the covering. Do I need to put something over >this joint? > >The front side called for 2 plys of UNI, at 90 degrees to each other. I >did the same thing on it, filled in with a small triangular piece of >cloth. I didn't worry about it because it got covered with the second >ply. Did I do this right? > >Thanks, > >Terry Pierce >Cozy Mark IV #600 > > Terry, I had the same question on a Saturday night at 10 PM. I put it on the net and had my answer. (Thanks Marc). The answer is that when you lay two pieces of uni side by side (with the glass fibers running parallel to the discontinuity in the cloth, all is fine. When you put two pieces of BID side by side, or when the discontinuity in the UNI is perpendicular to the weave, you must overlap the fibers. This is discussed in the education chapter. I don't recall off hand if the minimum overlap is 1" or 2". Steve **************************************** Stephen A. Campbell Associate Professor, EE University of Minnesota ***************************************** Date: Tue, 13 May 1997 10:13:17 -0500 From: tpierce@ghg.net (Terence J. Pierce) Subject: COZY: chapter 4,front seatback In chapter 4 on the front seatback, the back side calls for 1 ply of BID at 45 degrees. Being 42 inches wide, I had to add a small triangular piece of bid to finish the covering. Do I need to put something over this joint? The front side called for 2 plys of UNI, at 90 degrees to each other. I did the same thing on it, filled in with a small triangular piece of cloth. I didn't worry about it because it got covered with the second ply. Did I do this right? Thanks, Terry Pierce Cozy Mark IV #600 by InfoAve.Net (PMDF V5.1-7 #17060) with SMTP id <01IITILD57RU9JH2M4@InfoAve.Net> for cozy_builders@hpwarhw.an.hp.com; Tue, 13 May 1997 11:36:49 EST Date: Tue, 13 May 1997 11:33:09 -0400 From: Jeff S Russell Subject: Re: COZY: chapter 4,front seatback Organization: AEROCAD INC. Terence J. Pierce wrote: > > In chapter 4 on the front seatback, the back side calls for 1 ply of BID > at 45 degrees. Being 42 inches wide, I had to add a small triangular > piece of bid to finish the covering. Do I need to put something over > this joint? Terry, did you overlap this small piece to the larger piece by at least one inch? All BID that is not big enough to fit the part should always be overlapped by at least this much. This also includes BID tape to hold the bulkheads in place. UNI only needs butt joints. If you wish, you can peel ply over the seam to smooth out the overlap for later finishing. -- Jeff Russell/AeroCad Inc. E-mail: Jeff@aerocad.com Phone/ fax (call first): 910-961-2238 AeroCad: http://www.aerocad.com Composite workshop info: http://www.Sportair.com Date: Tue, 13 May 1997 11:55:35 -0400 From: bil kleb Organization: NASA Langley Research Center Subject: Re: COZY: chapter 4,front seatback Terence J. Pierce wrote: > > In chapter 4 on the front seatback, the back side calls for > 1 ply of BID at 45 degrees. Being 42 inches wide, I had to > add a small triangular piece of bid to finish the covering... > Did I do this right? this is covered in a cozy iv plans correction from newsletter 41 (see http://www.ultranet.com/~marcz/cozy_mkIV/newsletters/mkIV_correct.html) -- bil Date: Tue, 13 May 1997 12:05:10 -0500 From: tpierce@ghg.net (Terence J. Pierce) Subject: Re: COZY: chapter 4,front seatback Thanks everyone for the help. I did read chapter 3, but it was awhile ago. I guess I need to read it over again. Now to fix what I messed up. I did put peel ply over the joint, in case I had to add a ply of tape over the joint. I made two mistakes. One I didn't remove the slevege on the BID. And two, I made a butt joint. Should I cut the slevege off now? I know I need to put a piece of BID tape on, overlaping 1 inch on each side. Terry Pierce Cozy Mark IV #600 Terence J. Pierce wrote: > > In chapter 4 on the front seatback, the back side calls for 1 ply of BID > at 45 degrees. Being 42 inches wide, I had to add a small triangular > piece of bid to finish the covering. Do I need to put something over > this joint? > > The front side called for 2 plys of UNI, at 90 degrees to each other. I > did the same thing on it, filled in with a small triangular piece of > cloth. I didn't worry about it because it got covered with the second > ply. Did I do this right? > > Thanks, > > Terry Pierce > Cozy Mark IV #600 Subject: COZY: Front Seat Back From: gmellen@juno.com (George J Mellen Jr.) Date: Tue, 13 May 1997 14:24:31 EDT Should I cut the slevege off now? I know I need to put a piece of BID tape on, overlaping 1 inch on each side. I would not bother . You will have a slight joggle there, but no ones going to see it . You could sand the selvage down though Posted-Date: Wed, 14 May 1997 14:09:50 -0500 (CDT) Date: Wed, 14 May 1997 14:09:24 -0500 From: Darren DeLoach Subject: COZY: Chap 4 Alum Inserts For the small aluminum inserts on the firewall (and any more I do in the future): Should I alodine these guys first? The plans Chap 3 just says sand them and paint epoxy on (I assume this means immediately before glassing them in, so the epoxy is still wet on the aluminum...). I need to know whether to add alodine solution to my Wicks order or not. If I alodine them, do I still sand them and paint epoxy on immediately before glassing? TIA, -- Darren DeLoach http://www.deloach.com Garage is clean, jigging table finished, epoxy warming box done, ready to start! Date: Wed, 14 May 1997 13:30:38 -0600 (MDT) From: Ron Lee Subject: Re: COZY: Chap 4 Alum Inserts I will add my input based upon a discussion on this that was held several months ago. For any exposed aluminum pieces (and maybe even enclosed), I would clean the aluminum with something like alumiprep, then alodine. Supposedly epoxy sticks well to alodine so sanding after alodine would not be needed. Allow alodine to dry after treatment. Having said this, the people who really know will correct any gross mistakes I made!!!! Ron Lee At 14:09 97/5/14 -0500, you wrote: >For the small aluminum inserts on the firewall (and any more I do in the >future): > >Should I alodine these guys first? The plans Chap 3 just says sand them and >paint epoxy on (I assume this means immediately before glassing them in, so >the epoxy is still wet on the aluminum...). I need to know whether to add >alodine solution to my Wicks order or not. > >If I alodine them, do I still sand them and paint epoxy on immediately >before glassing? > >-- Darren DeLoach Date: Wed, 14 May 1997 17:38:26 -0700 From: Mahan Subject: Re: COZY: Chap 4 Alum Inserts Darren DeLoach wrote: I need to know whether to add alodine solution to my Wicks order or not. Darren, you can buy the aluminum prep and the alodine from your local auto paint store -- no need to ship it. Fred in Florida Date: Thu, 15 May 1997 22:23:32 -0400 From: INFINITY Aerospace Subject: COZY: Re: Chap 4 Alum Inserts Hi Bill and All, >sand (220 grit) the aluminum to get a rough surface so that the epoxy can make a decent _mechanical_ bond.< Use 60 to 80 grit. Infinity's Forever, JD From: Epplin John A Subject: RE: COZY: Several Chapter 4 questions Date: Wed, 20 Aug 1997 09:14:24 -0500 Darren: A hole saw works fine. Just use a little care and run it slowly with a variable speed drill. Tip: use a long pilot drill so the drill flutes are through the part before the saw contacts it or drill the pilot hole first and use a piece of drill rod as a pilot for the hole saw. I didn't cut these holes until last evening when I was putting in the torque tubes. I found that using the template leaves the holes about a half inch too close to the side wall. You may want to drill a small pilot hole for now and see how it comes out when you get to the control section. F28. I found the ends didn't mate with the longerons very well anyway. Fortunately I had to remove material to get a good fit. You might consider leaving the end cutouts with plenty of material for final fitting. The instrument panel and F22 locate the longerons at this point and F28 must be made to fit as the longerons will not flex appreciably at this point. Firewall. There is a cad drawing available on Marcs web site that is much better than trying to piece the original drawings together and then mirroring them. I ignored the cosmetic parts up till this time. When I get to that part maybe there will be a problem but I cant see it now. Hope this helps some. John Epplin Mk4 #467 > -----Original Message----- > From: Darren DeLoach [SMTP:ddeloach@texoma.net] > Sent: Wednesday, August 20, 1997 8:43 AM > To: cozy_builders@hpwarhw.an.hp.com > Subject: COZY: Several Chapter 4 questions > > 1. For the two 1" 45-degree holes on the seatback: How do I cut them > out? > Looking at the hole saws at my local hardware store, the large teeth > meant > for wood look like they would tear my part up leaving jagged edges on > the > glass. Maybe drill at a half inch, them ream them out? Some other > tool? > > 2. F28 using the "new rounded curvature": On the original curve, it > looks > like the cutout for the longerons would be "L"-shaped, and sit on the > outside edge of the part. Using the new curve, am I correct that I > should > cut out a squared "U" shape for the longerons (since the curve > continues on > past them), meaning they're contained inside the part? > > 3. On the permanent firewall parts: On the top portion of the > drawings, the > rounded piece on the outside is marked "cosmetic, installed in chapter > xxx" > or something similar. As I cut my 4 pieces, should I therefore > continue the > curve down then over toward the longeron cutout, leaving out the > portion > marked "cosmetic" (meaning, I guess, is the firewall really 6 pieces, > not > four)? > > Thanks in advance! > -- Darren DeLoach > http://www.deloach.com > Halfway done with Chap. 4 Mail-For: Date: Wed, 20 Aug 1997 11:51:19 -0500 From: Darren DeLoach Subject: RE: COZY: Several Chapter 4 questions >F28. I found the ends didn't mate with the longerons very well anyway. >Fortunately I had to remove material to get a good fit. You might >consider leaving the end cutouts with plenty of material for final >fitting. The instrument panel and F22 locate the longerons at this >point and F28 must be made to fit as the longerons will not flex >appreciably at this point. > Will do. My question was of the shape of the cutout itself, though: for the "new" curvature, it should be "U" shaped with more of F28 on the outside of the longeron hole, right? >Firewall. There is a cad drawing available on Marcs web site that is >much better than trying to piece the original drawings together and then >mirroring them. I ignored the cosmetic parts up till this time. When I >get to that part maybe there will be a problem but I cant see it now. > Got that and I'm using it. It includes the cosmetic parts though, my question is do I cut out my plywood into 4 parts, the top which includes the cosmetic part as does Lee's CAD drawing, or into 6 parts, the basic 4 plus two separate cosmetic parts. Also, on the temporary firewall which is a single large piece do I leave the cosmetic parts in? -- Darren DeLoach http://www.deloach.com Halfway done with Chap. 4 From: Marc J. Zeitlin Subject: RE: COZY: Several Chapter 4 questions (fwd) Date: Wed, 20 Aug 97 13:14:47 EDT Darenn DeLoach writes: >Will do. My question was of the shape of the cutout itself, though: for >the "new" curvature, it should be "U" shaped with more of F28 on the outside >of the longeron hole, right? I didn't find it to be shaped like that, if I'm interpreting your question correctly. The outer top sides of the F28 didn't change substantially - I think that it was only the center area that got raised a bit - I may be wrong, but I didn't have anything that wrapped over the top of the Longerons. >...... It includes the cosmetic parts though, my >question is do I cut out my plywood into 4 parts, the top which includes the >cosmetic part as does Lee's CAD drawing, or into 6 parts, the basic 4 plus >two separate cosmetic parts. The deal here (as far as I can tell) is that at some point you will have to cut off the "cosmetic parts" in order to do the outside layup that wraps from the turtleback/fuselage onto the firewall/engine mount hard point. I cut out the upper firewall and left the "c.p.'s" in place. I then installed the upper firewall into the turtleback with the inside and outside 2 BID tapes, but it's fairly obvious that the "c.p.'s" will have to be removed prior to the other layup. You can either cut them out at firewall cut out time, or wait until later - either way should work. >....... Also, on the temporary firewall which is a >single large piece do I leave the cosmetic parts in? Worked for me - the temp. firewall "c.p.'s" don't get in the way, so you can cut it out either way. -- Marc J. Zeitlin Email: marcz@an.hp.com From: DFinn7971@aol.com Date: Thu, 21 Aug 1997 07:24:27 -0400 (EDT) Subject: Re: COZY: Several Chapter 4 questions In a message dated 97-08-20 10:13:39 EDT, ddeloach@texoma.net (Darren DeLoach) writes: << 1. For the two 1" 45-degree holes on the seatback: How do I cut them out? Looking at the hole saws at my local hardware store, the large teeth meant for wood look like they would tear my part up leaving jagged edges on the glass. Try drilling the holes using one of the hole saws running in reverse. It will cut OK and will not tear out. 3. On the permanent firewall parts: On the top portion of the drawings, the rounded piece on the outside is marked "cosmetic, installed in chapter xxx" or something similar. As I cut my 4 pieces, should I therefore continue the curve down then over toward the longeron cutout, leaving out the portion marked "cosmetic" (meaning, I guess, is the firewall really 6 pieces, not four)? >> As I remember it (I'm out in Philadelphia and the plane and planes are in Chicago) you need to include the piece in the firewall. The cosmetic piece buts against this part of the firewall. Dick Finn Cozy Mark IV #46 DFINN7971@AOL.COM Mail-For: Date: Mon, 25 Aug 1997 09:53:33 -0500 From: Darren DeLoach Subject: COZY: Chap 4 Firewall holes Based on the archives and others' suggestions, I've skipped the torque tube holes in the seatback and LG bulkheads for now, to be done later when installing the tubes. I cut out all the firewall parts yesterday, and per plans did not cut out the longeron holes in the permanent firewall. I did do the alum insert holes. My question is: Should I cut the electrical duct holes and the torque tube holes in the firewall now, or like the other torque tube holes is it better to wait on these until later? Related question: In the LG bulkeads, the plans say drill the pair of quarter inch holes in the hardpoint area now on one of them, and do the other pair one on the other bulkhead later. Should I go ahead and drill the one pair of holes now per plans, or like the torque tube holes should I delay these two as well? -- Darren DeLoach http://www.deloach.com Halfway done with Chap. 4 Date: Tue, 26 Aug 1997 12:08:26 -0400 From: bil kleb Organization: NASA Langley Research Center Subject: Re: COZY: Chap 4 Firewall holes Darren DeLoach wrote: > > Should I cut the electrical duct holes and the torque tube > holes in the firewall now, or like the other torque tube holes > is it better to wait on these until later? i vote for waiting until you're in chapter 6 (fuselage assembly), and have thoroughly figured things out with your temporary firewall piece. however, for the same reasons as mentioned earlier, i still didn't drill the torque tube holes. > In the LG bulkeads...Should I go ahead and drill the one pair > of holes now per plans yes, it is easier that doing it after it is installed. the other pair of holes are delayed so that you can make a jig to be sure that the two sets of holes are lined-up once the two bulkheads are epoxied to the fuselage sides. -- bil Date: Wed, 27 Aug 1997 18:59:43 -0700 (PDT) From: rfisher@spacetech.com Subject: COZY: Chapter 4 - Instrument Panel After talking with Vance and Nat at Osh, I've pretty much decided that I'm going to have to raise my canopy (when I get there :-) ) at least one inch. Since I know in advance that I will be doing this, I was thinking about raising the instrument panel an inch also. This would give me another inch of thigh room, hopefully making us feel a little less confined. Do any of you who have gotten far enough to know see any reason why this won't work? I've looked over the plans, and the way I see it, with the canopy up an inch, there should be room for a higher inst panel. Whatcha think? See ya, Russ Fisher From: N11TE@aol.com Date: Thu, 28 Aug 1997 00:02:11 -0400 (EDT) Subject: Re: COZY: Chapter 4 - Instrument Panel I used the Lancair 320 canopy to accomplish the same objective of increasing headroom. Plus, it was much less expensive. I originally installed the instrument panel 1-1/2 in higher than plans. This weekend I looked at it and realized there might be a conflict with the boxes I wanted to install so I cut out cardboard boxes and checked for fit. I did find a problem so I just went back and lowered the instrument panel to 1" higher than plans. This, along with the fact that I removed the vertical center support, has made a large increase in leg room. I also used the AeroCad 3-dimensional instrument panel (which works great!) and installed it to be totally removable. Again note that you are your own airplane manufacturer and you can make any changes you feel comfortable with. I only list these changes to let people know what I have decided to do. Tom Ellis N11TE@aol.com Cozy MK IV plans #25 Now AeroCanard 540 From: AlWick@aol.com Date: Thu, 28 Aug 1997 01:28:14 -0400 (EDT) Subject: Re: COZY: Chapter 4 - Instrument Panel In a message dated 97-08-27 23:09:53 EDT, you write: << After talking with Vance and Nat at Osh, I've pretty much decided that I'm going to have to raise my canopy (when I get there :-) ) at least one inch. Since I know in advance that I will be doing this, I was thinking about raising the instrument panel an inch also. This would give me another inch of thigh room, hopefully making us feel a little less confined. Do any of you who have gotten far enough to know see any reason why this won't work? I've looked over the plans, and the way I see it, with the canopy up an inch, there should be room for a higher inst panel. Whatcha think? >> I'm 6'2", looks like I DON'T need to raise canopy. But all you have to do is make the FWD jig ribs for the turtleback taller. That way you don't get caught up in unnecessary mods like firewall, engine covers, etc. Leave the rear turtleback jigs stock. No mods necessary till you get to the very end of the process. I wouldn't make panel taller, would just increase opening at your feet. Would also require moving lower panel rib up a bit. Not sure of effect on fit of instruments. Good luck! -al Date: Thu, 28 Aug 1997 19:38:29 -0700 (PDT) From: rfisher@spacetech.com Subject: Re: COZY: Chapter 4 - Instrument Panel On Thu, 28 Aug 1997, N11TE@aol.com wrote: >I used the Lancair 320 canopy to accomplish the same objective of increasing >headroom. Plus, it was much less expensive. Sounds interesting, is your tub stock width or did you widen it? >I originally installed the instrument panel 1-1/2 in higher than plans. This >weekend I looked at it and realized there might be a conflict with the boxes >I wanted to install so I cut out cardboard boxes and checked for fit. What "boxes" are you referring to? >Again note that you are your own airplane manufacturer and you can make any >changes you feel comfortable with. I only list these changes to let people >know what I have decided to do. I understand, but I'm trying to stay as close to the plans as possible since I am no aeronautical engineer. I was just trying to find out if there was any known problem with adding an inch to the top of the panel since the canopy was going to be an inch higher. Thanks for your input. Russ Fisher Date: Mon, 1 Sep 1997 20:16:06 -0700 (PDT) From: rfisher@spacetech.com Subject: Re: COZY: Chapter 4 - Instrument Panel Hi Phil, Lois and Emma, I thought about the visibility thing too. I figure, though, if Nat with his short little frame can see over the standard panel, I ought to be able to see over one that is only one inch higher. My original thought was to make the leg holes per plans and extend the top of the panel one inch. That way, if the top worked out, I could just cut the leg holes bigger - otherwise I could cut the top back down. The problem here is that electrical chanel just above the leg holes. If I place it according to plans, I can't cut the leg holes bigger. If I place it one inch higher, I may as well make the leg holes bigger from the start, 'cause the space between it and the holes is useless anyway. Doing it this way, however, means that if I have to cut the top down, I've lost an inch of panel space - something I don't want to do. My real main concern is, with the top one inch higher, will I be able to fair everything in to the top of the panel cleanly? I'm not worried about the canopy hitting it, it will be 1-1/2 to 2 inches higher anyway. But instead of the top of the panel being flush with the top of the longerons, it will now be an inch higher. My gut feeling is that with a lot of urathane foam and some patience, I should be able to make everything look ok. The reason for my posting was to find out if there were any hidden "gotchas" that I should look out for. Thanks for your reply, Russ Fisher On Sat, 30 Aug 1997, "Johnson, Phillip" wrote: >Russ, > >I raised my canopy about two inches which allowed me significant head >room. Raising the instrument panel may reduce your visibility slightly >so you may want to reconsider this. If you build the instrument panel a >little higher now you can always cut it down later. It is more difficult >to add height at a later date. I suggest that you go ahead with height >panel now but be prepared to cut it back later. > >Lois & Emma say hello. > >Phillip Johnson > Date: Tue, 2 Sep 1997 20:31:41 -0700 (PDT) From: rfisher@spacetech.com Subject: RE: COZY: Chapter 4 - Instrument Panel On Tue, 2 Sep 1997, "Johnson, Phillip" wrote: >Russ, > >The simple solution is not to install the lower electrical conduit now, >do it at a later date. The upper electrical conduit will provide you >with enough stiffness. > >You might want to consider the Vance Atkinson instrument panel. This is >where you remove the foam in the vicinity of the instruments and add >five more plies of BID to give the strength. This makes instrument >installation a lot easier and smarter. Phil, Good idea. I have been toying with the idea of using an aluminum insert, although I spent over an hour this evening talking with Tom Ellis who used Aerocad's panel which is angled in a little on the passenger side. I've seen this in other types of planes and really like it. One reassuring note from Tom was to go ahead and build it - it can always be changed later. We'll see. Thanks again - Joan says hi. See ya, Russ Fisher From: Greg and Jill Hilliard Subject: COZY: ch 4, f28 contour Date: Sun, 14 Sep 1997 23:04:19 -0500 Greetings, cozy folk. I am happy to say that cozy mk4 #456, after two years, is out of the = pre-build stage and into chapter 4. Seatback & f22 done, wondering about = f28. In newsletter 36, we're told to change the 3.3" dim to 4.0", for a more = rounded appearance. Is any pleasing contour ok here or is there a = specific shape you all have followed? I've plotted out the cad files on = this subject, but don't trust my plotter enough to go off them. If it's = no big deal as I suspect, I'll just proceed with a "nice" 4 inch f28. Thanks in advance, Greg Hilliard cozy mk4 #456 gjhilliard@idcnet.com From: Marc J. Zeitlin Subject: COZY: ch 4, f28 contour (fwd) Date: Mon, 15 Sep 97 9:01:24 EDT Greg; > I am happy to say that cozy mk4 #456, after two years, is out of the >pre-build stage and into chapter 4. Seatback & f22 done, wondering about >f28. Congratulations! >.... Is any pleasing contour ok here or is there a >specific shape you all have followed?........ If it's >no big deal as I suspect, I'll just proceed with a "nice" 4 inch f28. "nice" is the operative word here. This is purely a cosmetic issue. The original size made it look square and boxy - some people have raised f28 even more for a more rounded look. -- Marc J. Zeitlin Email: marcz@an.hp.com From: cdenk@ix.netcom.com Date: Mon, 15 Sep 1997 18:30:49 -0500 (CDT) Subject: Re: COZY: ch 4, f28 contour (fwd) The height of F-28 determines your forward lower sightline. Ideally as low as possible, but high enough to clear instrument panel items. The Cosy Classic had a specific shape for the top. I don't think it wants to be any higher. From: cdenk@ix.netcom.com Date: Mon, 15 Sep 1997 20:57:47 -0500 (CDT) Subject: Re: COZY: ch 4, f28 contour On 09/14/97 23:04:19 you wrote: > >Greetings, cozy folk. > I am happy to say that cozy mk4 #456, after two years, is out of the >pre-build stage and into chapter 4. Seatback & f22 done, wondering about >f28. > In newsletter 36, we're told to change the 3.3" dim to 4.0", for a more >rounded appearance. Is any pleasing contour ok here or is there a >specific shape you all have followed? I've plotted out the cad files on >this subject, but don't trust my plotter enough to go off them. If it's >no big deal as I suspect, I'll just proceed with a "nice" 4 inch f28. > Thanks in advance, > >Greg Hilliard > To loft (draw) nice curves I know 3 methods: 1: Use Autocad to spline the curve. 2: Use something homogenous (not wood with wild grain) like a strip of metal or plastic (I like steel strap iron for long curves). Keep tight (tangent) at meeting surfaces, slide in or out to get roundness you need. 3: Once you have a curve, rock a steel strip on edge over the curve. It will click or you will feel a flat spot easily with little practice. I prefer the backside of a hacksaw blade, or the 12" steel rule from a combination square. Of course all the above items must be perfectly straight and no nicks in the edges. For long straight, I prefer a 7' paperhangers alum. straight edge, $40 at your local paint store. Date: Mon, 22 Sep 1997 07:40:39 +0200 From: Rego Burger Subject: COZY: Firewall-Engine Mnt. Hardpoints. I thought I could do the mounting of the +/- 2" squares one day like this past week. These are the ones inside the cabin. Well let me tell you floxing them in the vertical is not easy, they simply slip down...I think it's gravity's fault. Solving this problem was easy...I drilled a 6mm hole through all the parts and "clamped" it in place. Now, when it came to removing the bolts...mmm....! I now found a new use for epoxy...Lock TiTe ! The heads just sheared off...now I can practice my skills of drilling out sheared bolts. Please if anyone wants to try this trick just remember to apply some release agent to the threads. Even better simply apply the 2024 -T3 rear support pads on while you have the firewall loose and horizontal...much easier. Happy Building. Rego Burger CZ4#139 RSA Date: Mon, 22 Sep 1997 10:52:20 -0500 From: Bulent Subject: Re: COZY: Firewall-Engine Mnt. Hardpoints. HI Rego, About your bolts glued in the epoxy: I had removed parts like that epoxied solid by not so bright friend of mine, by heating fast the metal with a propane torch while pulling on the part. Only the epoxy touching the metal melts and releases the metal without heating the rest of the aerea. Good luck. Bulent CZ MK-IV #66 From: cdenk@ix.netcom.com Date: Mon, 22 Sep 1997 20:07:48 -0500 (CDT) Subject: Re: COZY: Firewall-Engine Mnt. Hardpoints. On 09/22/97 11:02:54 you wrote: > >This technique also works for removing mis-located or damaged canard >hangars from canards. > >Fred in Florida > >---------- >> From: Bulent >> To: Rego Burger >> Cc: Cozy Builders >> Subject: Re: COZY: Firewall-Engine Mnt. Hardpoints. >> Date: Monday, September 22, 1997 11:52 AM >> >> HI Rego, >> About your bolts glued in the epoxy: I had removed parts like that >> epoxied solid by not so bright friend of mine, by heating fast the metal >> with a propane torch while pulling on the part. Only the epoxy touching >> the metal melts and releases the metal without heating the rest of the >> aerea. Good luck. >> Bulent >> CZ MK-IV #66 > > Any epoxy (except for those few that are intended for higher temperature service) that is heated above say 200 degrees F should be removed (and the fibers that go with it). I wish people would try to put appropriate cautions with their messages if they are aware, or question the procedures to the group before doing it. I realize that this is no small undertaking, where we get too old to soon, and to smart to late. From: cdenk@ix.netcom.com Date: Mon, 22 Sep 1997 20:12:31 -0500 (CDT) Subject: Re: COZY: Firewall-Engine Mnt. Hardpoints. On 09/22/97 07:40:39 you wrote: > >I thought I could do the mounting of the +/- 2" squares one day like >this past week. These are the ones inside the cabin. > >Well let me tell you floxing them in the vertical is not easy, they >simply slip down...I think it's gravity's fault. Solving this problem >was easy...I drilled a 6mm hole through all the parts and "clamped" it >in place. >Now, when it came to removing the bolts...mmm....! I now found a new use >for epoxy...Lock TiTe ! The heads just sheared off...now I can practice >my skills of drilling out sheared bolts. > >Please if anyone wants to try this trick just remember to apply some >release agent to the threads. Even better simply apply the 2024 -T3 rear >support pads on while you have the firewall loose and horizontal...much >easier. > >Happy Building. > >Rego Burger >CZ4#139 >RSA > > A light coating of oil, grease, vaseline, or wax usually work fine. From: "Ian Martin" Subject: COZY: Re: Firewall Date: Fri, 26 Sep 1997 15:23:07 -0700 Hello Fellow Builders, I could use some help in understanding why the firewall is built in four pieces and why is there a large hole in the center? Also when is it needed, though the plans say chapter 4, it appears that it is not needed till chapter 6, and that you use the temporary firewall as a template. If it is in four pieces where is the strength, one might think that its in reality just a solid core material. Trying to determine if a ACS&S run is necessary this weekend. Thanks for the insight ------------------------------------------------------------------------------- J. Ian Martin Phone: (619) 874-7000 x184 4950 Murphy Canyon Rd. San Diego, CA. 92123 email: imartin@gstone.com From: Marc J. Zeitlin Subject: COZY: Re: Firewall (fwd) Date: Sun, 28 Sep 97 16:56:44 EDT Ian Martin wrote: > I could use some help in understanding why the firewall is built in four >pieces and why is there a large hole in the center? Also when is it needed, >though the plans say chapter 4, it appears that it is not needed till chapter >6, and that you use the temporary firewall as a template. The two main piece are used seperately - the bottom when assembling the fuselage tub, and the top when assembling the turtleback. The space in between is where the main spar goes, in chapter 14/19. You don't need it until chapter 6, but since you're making all the other bulkheads in chapter 4, that's where it goes. The two small pieces go between the large pieces in the space behind the spar - I believe they hold some rudder cable hardware, which couldn't just be bolted to the rear of the spar (no hardpoints). It's a good idea to read the whole plan set through at least once or twice, so that you have a good idea of why you're doing what you're doing at the time you're doing it. Even though I did that, I still killed myself trying to get the UNI fibers on the inside fuselage side layups to lay down flat over the pointy longerons, when, if I had just paid attention, I would have known that I was just going to cut the dang things off and chuck them in chapter ??? when I started to do the fuselage front where the canard goes. -- Marc J. Zeitlin Email: marcz@an.hp.com From: lschuler@cellular.uscc.com Date: Mon, 29 Sep 97 12:28:40 -0600 Subject: COZY: Re: Firewall --simple boundary Content-Type: text/plain; charset=US-ASCII Content-Transfer-Encoding: 7bit Ian Martin wrote: >I could use some help in understanding why the firewall is built in four >pieces and why is there a large hole in the center? Also when is it needed, >though the plans say chapter 4, it appears that it is not needed till chapter >6, and that you use the temporary firewall as a template. It's actually 5 pieces. Number one reason it's in pieces is so you can get the center spar mounted. The bottom piece will be installed fairly soon; when the fuselage tub and bulkheads are put together. The top piece is installed about the time you do the turtleback and after the center spar is in. The hole in the middle as you call it, is filled in with a sheet of foam after the center spar is installed and the other pieces are in place. The two outside pieces are used for some control brackets later. You do need to make a firewall jig from the drawings. The jig must be of the entire firewall (no pieces). I made mine out of 1/2" plywood reinforced with trued-up (planed) 2X4s to keep it from warping and to make sure it was dead flat (still is flat after two years). Hope this helps. Larry Schuler #500 starting ch-10 lschuler@cellular.uscc.com --simple boundary Content-Type: text/plain; charset=US-ASCII; name="RFC822.TXT" Content-Transfer-Encoding: 7bit Content-Disposition: attachment; filename="RFC822.TXT" Received: from gatekeep.uscc.com by cellular.uscc.com (ccMail Link to SMTP R8.00.01) ; Fri, 26 Sep 97 17:27:04 -0600 Return-Path: Received: from www.uscc.com (www.uscc.com [204.179.101.2]) by gatekeep.uscc.com with ESMTP id SAA08456 for ; Fri, 26 Sep 1997 18:23:24 -0400 (EDT) Received: from palrel1.hp.com (palrel1.hp.com [156.153.255.235]) by www.uscc.com with ESMTP id RAA06451 for ; Fri, 26 Sep 1997 17:24:07 -0500 (CDT) Received: from hpwarhw.an.hp.com (hpwarhw.an.hp.com [15.57.193.122]) by palrel1.hp.com (8.8.6/8.8.5tis) with SMTP id PAA06027 for ; Fri, 26 Sep 1997 15:26:09 -0700 (PDT) Received: by hpwarhw.an.hp.com (1.37.109.8/15.5+IOS 3.22) id AA28039; Fri, 26 Sep 1997 18:25:27 -0400 Received: from hp.com by hpwarhw.an.hp.com with SMTP (1.37.109.8/15.5+IOS 3.22) id AA28034; Fri, 26 Sep 1997 18:25:26 -0400 Received: from indy3.gstone.com ([199.35.226.23]) by hp.com (8.8.5/8.8.5tis) with ESMTP id PAA13186 for ; Fri, 26 Sep 1997 15:23:32 -0700 (PDT) Received: from imartin.gstone.com (imartin.gstone.com [199.35.226.148]) by indy3.gstone.com (8.8.5/8.8.3) with ESMTP id PAA10588 for ; Fri, 26 Sep 1997 15:16:50 -0700 (PDT) Message-Id: <199709262216.PAA10588@indy3.gstone.com> From: "Ian Martin" To: "builders list" Subject: COZY: Re: Firewall Date: Fri, 26 Sep 1997 15:23:07 -0700 X-Msmail-Priority: Normal X-Priority: 3 X-Mailer: Microsoft Internet Mail 4.70.1161 Mime-Version: 1.0 Content-Type: text/plain; charset=ISO-8859-1 Content-Transfer-Encoding: 7bit Sender: owner-cozy_builders@hpwarhw.an.hp.com Precedence: bulk Reply-To: "Ian Martin" --simple boundary-- Date: Mon, 6 Oct 1997 20:52:17 -0700 (PDT) From: rfisher@spacetech.com Subject: COZY: Chap. 4 - Bulkheads Well, have 37 hours on my project and have the front seat-back, F22, F28 and the instrument panel done. Nat suggests that the entire chapter should take about 25 hours. Either he's not figuring in the time for tracing and cutting out patterns, or I'm being WAAAAAAY too anal about getting things right. Speaking of patterns, has anyone else noticed on drawing M3, that the bottom of the instrument panel is more than 1/8" farther from the horizontal match line in the center than it is in the corner. If you went by the match lines, the panel would have a shallow 'V' bottom. I called Nat about this, he asked how the bottom of F22 turned out. I said "flat", he said "go ahead and make the panel flat too - it's not a critical dimension." And the landing gear bulkheads! Forget about tracing them - they're so far off it's not even funny. That must be why there are so many dimensions on them. Since I don't have access to an accurate plotter, I'm stuck with drawing them from scratch. Kind of makes you wonder about the accuracy of the other drawings - you know, the ones without any dimensions to verify. Anyway, after perusing the archives, I decided to get a piece of G-10 for the landing gear attach points. The first plastics dealer I called had a piece of scrap the exact size I needed - $15. I asked him how to cut it, and he said "good luck, we use a diamond blade." I'm happy to report that it cuts perfectly fine with a carbide tipped saw blade in my table saw - 60 tooth, I don't think I would use anything less. For tha inside cuts and curves, I used a carbide coated jig saw blade - Black & Decker #75-191, M grit. Got it at the local home builder store for about $5. Cuts the stuff like butter. The archives mentioned that G-10 eats band saw blades, and since mine was brand new, I thought I'd try something else. Carbide is the answer. Enough rambling, I have to go knife trim the instrument panel and go to bed. See ya, Russ Fisher rfisher@spacetech.com Date: Tue, 7 Oct 1997 20:39:14 -0700 (PDT) From: rfisher@spacetech.com Subject: Re: COZY: Chap. 4 - Bulkheads On Tue, 07 Oct 97, lschuler@cellular.uscc.com wrote: > > Wait till you get to the canard templates; make up the templates and > try to match them for drilling the nail holes..... Good luck matching > them. That's were I'm at at the moment. > > And don't try to measure one inch between water line marks on the side > of the firewall drawing.... > > Larry Schuler #500 ch-10 > lschuler@cellular.uscc.com Ok, here's a question, then. I've heard claims that the cad files on Marc's page are extremely accurate. Accurate to what? From what I'm reading, it's anyone's best guess as to how these parts are to be constructed. With no dimensions given on the patters, and "match lines" that don't match, what did the creator of these files use as a pattern? See ya, Russ Fisher rfisher@spacetech.com From: Marc J. Zeitlin Subject: Re: COZY: Chap. 4 - Bulkheads (fwd) Date: Wed, 8 Oct 97 8:46:34 EDT Russ Fisher asks: >Ok, here's a question, then. I've heard claims that the cad files on Marc's >page are extremely accurate. OK, small engineering definitional regression here. We've got two terms - "accurate" and "precise". If someone tells you that their airspeed measures 167.685 kts., that's "precise", but it sure isn't "accurate". "Accuracy" is a measure of how close something is to what it should be - what's the error? "Precision" is a measure of how well something is defined - it could still be completely wrong, but perfectly defined. >........ Accurate to what? I think that people have meant a combination of "precision" and "accuracy" when speaking of the CAD files of the bulkheads. >........ From what I'm reading, it's >anyone's best guess as to how these parts are to be constructed. With no >dimensions given on the patters, and "match lines" that don't match, what did >the creator of these files use as a pattern? The bulkhead CAD files were created by Lee Devlin, using the templates _AS WELL AS THE DIMENSIONS CALLED OUT IN THE PLANS AND TEMPLATES_. Since they were created in a CAD tool by a (assumedly) competant drafter, we can state that they are more accurate than the paper templates would be, as well as being _perfectly_ symmetric - something the templates certainly aren't. They will also be far more "precise", but we don't give a ?$%@ about "precision" here - you can't cut to 0.001" with a hacksaw blade anyway. So, they're not perfect, and certainly not completely "accurate" (since all the dimensions to define every part in the plane aren't given anywhere [this drives me, as a M.E., completely nuts :-) ]) but they're better than the original alternative. Whether it makes a difference on anything other than the airfoil templates (or even there, given the number of aircraft that have been built and flown using the current methodology) is a matter for each person to decide for themselves. -- Marc J. Zeitlin Email: marcz@an.hp.com From: Lee Devlin Subject: Re: COZY: Chap. 4 - Bulkheads Date: Wed, 8 Oct 97 11:56:52 MDT Russ wrote: > Ok, here's a question, then. I've heard claims that the cad files on Marc's > page are extremely accurate. Accurate to what? From what I'm reading, it's > anyone's best guess as to how these parts are to be constructed. With no > dimensions given on the patters, and "match lines" that don't match, what did > the creator of these files use as a pattern? It's in the 'Readme' file that is in the CAD files section of Marc's www page. Please don't use the CAD files unless you have read it completely. The following is a document that describes the files for printing out full sized bulkhead templates for the Cozy MkIV. I am contributing these files for free to all Cozy builders with the stipulation that I cannot guarantee their fitness for use. I have just started building the plane and don't know if any errors crept into my measurements of the original templates. I have printed them out on vellum and laid them over the originals and am satisfied that they are close enough and have accuracy that is at least on par with tracing the templates by hand. I know that the symmetry is perfect since the images are mirrored about the center. There are small differences with the curvatures, as matching up splines can never be exact, but the critical dimensions are the same as originals. .... Using the CAD templates is a convenience and not necessarily a way to achieve greater accuracy. Most of the Chapter 4 templates are mirrored by hand by the builder so if they don't match up you can't blame the designer. I think that the top section of the instrument panel is the only template that has a left and right-hand pattern. My plans templates matched up to at least the degree of accuracy achievable with the moldless construction technique (~l/32"). Lee Devlin Posted-Date: Sat, 11 Oct 1997 14:55:17 -0500 (CDT) From: "Darren DeLoach" Subject: COZY: Drawing M-5 discrepancy Date: Sat, 11 Oct 1997 14:56:23 -0500 I put off drilling the holes in the forward gear bulkhead, and just now prepared to do them when I ran into a problem with drawing M-5. According to the measurements on the left side of the drawing, the hole should be at 5.5 - 4.3 = 1.2 inches from the top flat side, and 16.25 - 13 = 3.25 inches from the left. However, when you actually measure the hole you drew in the bulkhead it's at 1.45 inches from the top, a full 0.25 inches off of the calculated location. The line labeled 4.3 is actually 4.15 inches long when measured, accounting for the quarter inch difference. So which is correct: 1.2 inches from top per the computation, or 1.45 inches from top per the actual drawing? -- Darren http://www.deloach.com Finished with Chap 4 this weekend! Posted-Date: Sat, 11 Oct 1997 16:16:07 -0500 (CDT) From: "Darren DeLoach" Subject: Re: COZY: Drawing M-5 discrepancy Date: Sat, 11 Oct 1997 16:18:04 -0500 > Darren, I assume your talking about the hole for the touque tube? No, the holes for the landing gear in the middle of the 22-layer hardpoint. You're supposed to drill two in the forward gear bulkhead now, and the other two in the aft bulkhead in a later chapter. -- Darren http://www.deloach.com Date: Sat, 11 Oct 1997 23:14:43 -0400 From: Jim Hocut Subject: Re: COZY: Drawing M-5 discrepancy >So which is correct: 1.2 inches from top per the computation, or 1.45 >inches from top per the actual drawing? > I vaguely remember something about this. If my recollection is correct the "problem" has to do with the fact that the top of this bulkhead is cut at a 45 deg angle, so it's just a matter of where you do the measuring from. From: wkasty@ix.netcom.com Date: Sun, 12 Oct 1997 09:48:30 -0500 (CDT) Subject: Re: COZY: Drawing M-5 discrepancy On 10/11/97 14:56:23 you wrote: > >I put off drilling the holes in the forward gear bulkhead, and just now >prepared to do them when I ran into a problem with drawing M-5. According >to the measurements on the left side of the drawing, the hole should be at >5.5 - 4.3 = 1.2 inches from the top flat side, and 16.25 - 13 = 3.25 inches >from the left. However, when you actually measure the hole you drew in the >bulkhead it's at 1.45 inches from the top, a full 0.25 inches off of the >calculated location. The line labeled 4.3 is actually 4.15 inches long >when measured, accounting for the quarter inch difference. > >So which is correct: 1.2 inches from top per the computation, or 1.45 >inches from top per the actual drawing? > >-- Darren >http://www.deloach.com > >Finished with Chap 4 this weekend! > > > Hi Darren, I remember coming across this discrepancy. I decided to use the drawing for my hole location because it was closer to the center of the hardpoint. After drilling it, a fellow builder at work , who is an AP, said he would have trusted the dimensions (1.2) instead. I was upset to have to go through this mental torture thinking of how I screwed up the angle of incidence of the whole airplane and how I would correct it! Well, later when I was mounting the landing gear strut, the mistake didn't make any difference really. I elongated the holes upwards towards the 1.2 dimension. The gear came out in (as close as I can measure) the exact correct position reference the F.S.. Considerations for vertical placement are: 1. clearance of the gear cover door. 2. clearance of the angled supports on top of the forward attach points, which is very close using the 1.2 When I went back to measure from the center of the attach hole to the approximate top of the bulkhead( its hidden in layers of glass) the 1.2 still looks good to me. In the long run there are alot of tolerances built in to a plans-built airplane. Maybe one mistake will offset another. Every plane will be a bit different in the end. If you measured this same dimension on 100 different airplanes you would get 100 different measurements, but most would fall within a close proximity. Bill Kastenholz wkasty@ix.netcom.com From: wkasty@ix.netcom.com Date: Sun, 12 Oct 1997 11:37:19 -0500 (CDT) Subject: Re: COZY: Drawing M-5 discrepancy I forgot to say after elongating the holes, they get drilled out to a larger size for the bearings. So even if you made a mistake early, in this case, no damage is done. Bill Kastenholz Date: Sat, 18 Oct 1997 15:17:45 -0400 From: Jim Hocut Subject: Re: COZY: Chapter 4 Seatback Bulkhead whittaker@mindspring.com (Glen Whittaker) wrote: > >If the intent is to form a 45 degree bevel, shouldn't we taper the top edge >by 0.75" instead of 0.65"? > Don't have plans or a fuselage in front of me for reference so can't quote numbers, but am sure that the top of the seat-back is supposed to be parallel with the top longerons. Whatever the angle of incline on the seatback will be the angle on the top of the seatback. Jim Hocut jhocut@mindspring.com Date: Sat, 18 Oct 1997 20:47:12 -0400 (EDT) From: whittaker@mindspring.com (Glen Whittaker) Subject: COZY: Chapter 4 Seatback Bulkhead Refer to Chapter 4 Page 1, Fig 2 I just finished cutting the 28.8" X 42" foam for the front seatback. The plans say that we should taper the top edge of the foam by 0.65". The foam is 0.75" thick. If the intent is to form a 45 degree bevel, shouldn't we taper the top edge by 0.75" instead of 0.65"? I also noticed that the Front Seat Back Side Template has lines that are 0.75" apart. Glen Whittaker Cozy Mk IV # 0563 From: "Steve Campbell" Subject: RE: COZY: Chapter 4 Seatback Bulkhead Date: Mon, 20 Oct 1997 09:28:52 On Mon, 20 Oct 1997 08:52:57 -0500, EpplinJohnA@JDCORP.deere.com wrote... > > >It was hared for me to visualize how this thing fit at >first. I finally made copies of the large drawings and pieced them >together from nose to firewall and taped them on the wall. This helped >a lot, also kind of gives you a better overall perspective of what you >are going to end up with. > Let me second this. I did the same thing about two months ago. It really helps the first time builder visualize the big picture. I wish I had done it at the start of the project. Now when I have difficulty understanding a detail drawing, I refer to my picture wall, and it often makes more sense. Steve ************************************************ Stephen A. Campbell, Associate Professor, ECE University of Minnesota 200 Union Street Minneapolis 55455 (612) 625-5876 phone / (612) 625-4583 fax Campbell@ee.umn.edu ************************************************* From: Marc J. Zeitlin Subject: COZY: Chapter 4 Seatback Bulkhead (fwd) Date: Mon, 20 Oct 97 9:38:54 EDT Glen Whittaker writes: >If the intent is to form a 45 degree bevel, shouldn't we taper the top edge >by 0.75" instead of 0.65"? Yep. Ask Nat about this. It's not critical, and as Jim Hocut says, it's just supposed to be horizontal where it meets the longerons. I'd venture a guess that this is a typo of some sort, or just a slight mismeasurement of a part that Nat had already built. Another possibility is that since you can't make a perfectly sharp corner with that blue foam (or any foam, for that matter), you end up with the taper being a bit shorter than the theoretical distance. >I also noticed that the Front Seat Back Side Template has lines that are >0.75" apart. Go with that - but again, it's not critical. -- Marc J. Zeitlin Email: marcz@an.hp.com From: Epplin John A Subject: RE: COZY: Chapter 4 Seatback Bulkhead Date: Mon, 20 Oct 1997 08:52:57 -0500 > Refer to Chapter 4 Page 1, Fig 2 > > I just finished cutting the 28.8" X 42" foam for the front seatback. > The > plans say that we should taper the top edge of the foam by 0.65". The > foam > is 0.75" thick. > > If the intent is to form a 45 degree bevel, shouldn't we taper the top > edge > by 0.75" instead of 0.65"? > > I also noticed that the Front Seat Back Side Template has lines that > are > 0.75" apart. > > Glen Whittaker > Cozy Mk IV # 0563 > > [Epplin John A] I measured the seatback angle on one of the large drawings and cut the same angle on the foam. If I remember correctly, it was not quite 45 deg. It was hared for me to visualize how this thing fit at first. I finally made copies of the large drawings and pieced them together from nose to firewall and taped them on the wall. This helped a lot, also kind of gives you a better overall perspective of what you are going to end up with. Good luck and have fun. John epplin Mk4 #467 Date: Wed, 22 Oct 1997 22:46:46 +0100 From: Paul Kuntz Subject: COZY: Chapter 4 Seatback Bulkhead Glenn, As Marc said in his reply, this angle is simply not that critical over the relatively small thickness of the seat back. I had the same question when I built the seat back bulkhead. Since this is the first thing we all build, we want to get everything exactly right because we don't know yet how it's all going to go together eventually. We haven't built anything yet when we start Chapter 4, so we are afraid that we are going to make a mistake. In my case, not knowing the exact angle really bothered me, so I spent the time to look through the plans for something that would answer the question. The answer is in Chapter 6, figure 15 which shows the dimensions for the seat back brace. A little trigonometry applied to those dimensions reveals the actual seat back angle, which as I recall is something like 41 degrees, rather than the 45 degrees mentioned in the Chapter 4 instructions. Not having my scientific calculator at hand, I'm not sure what the tangent of .65/.75 is, but it's probably close enough to the right angle that you don't have to worry about it. Knowing the right angle made me feel better at the time, though. You'll get a better feel for these things as you proceed through the plans. As far as the seat back bulkhead is concerned, 41 degrees vs 45 degrees is not a problem and a standard 45 degree triangle can be used to lay out the cuts. What I will confirm, based on my own progress through Chapter 9 is that if you follow the plans exactly, having carefully applied all the changes from the newsletters, everything will fit perfectly. A couple of times I was convinced I had found a new error, but was later proven wrong. Stick with the plans and it will all become clear later if it doesn't seem so right now. I would also note that at times some minor point may appear to be missing or unclear, but if you dig around a bit in the plans, the answer is always there somewhere. I'm continually amazed at how Nat did all this and got it so nearly perfect, even considering the fact that he started with the MK 3 experience. What's even more amazing is how he designed and built the original Cozy from scratch all by himself, and how Burt came up with the original Varieze and Longeze designs that we all benefit from. As you proceed, imagine having to look ahead to all the design details before you build those first components. I for one am extremely grateful for such a good set of plans. They have given me a lot of confidence and have kept me from having to do any rebuilding of parts to correct mistakes. Good luck, Paul Kuntz Date: Sun, 7 Dec 1997 22:46:49 -0500 (EST) From: whittaker@mindspring.com (Glen Whittaker) Subject: COZY: Chapter 4 Bulkheads Question 1. On page 1 of chapter 4, we are instructed to trim the corners of the seat back bulkhead before glassing the backside. I am wondering if there would be less chance of damaging the foam if the back was glassed first. Can we glass the front and back sides first and then trim the corners after curing? Question 2. Can we destroy the structural integrity of the airframe by installing too many instruments on the instrument panel? I would think that each hole drilled into the panel would make the panel a little weaker. Glen Whittaker Cozy Mk IV 0563 From: Marc J. Zeitlin Subject: COZY: Chapter 4 Bulkheads (fwd) Date: Mon, 8 Dec 97 11:45:59 EST Glen Whittaker asks; >On page 1 of chapter 4, we are instructed to trim the corners of the seat >back bulkhead before glassing the backside. I am wondering if there would >be less chance of damaging the foam if the back was glassed first. Can we >glass the front and back sides first and then trim the corners after >curing? You can certainly do it in this order, but I don't think it would make a difference either way. Sometimes I'll glass panels and cut parts out of them - sometimes I'll cut the foam to shape and then glass each side. Depends on the situation and how much I'm glassing. For the seatback, it's 6 of one, 1/2 dozen of the other, I think. >Can we destroy the structural integrity of the airframe by installing too >many instruments on the instrument panel? This is the least of your worries :-). >....... I would think that each hole >drilled into the panel would make the panel a little weaker. It does, but you'd have to have no material at all between the instruments and/or between the instruments and the top/bottom of the panel before it would matter. Also, you'd have to destroy the stiffeners (both top and bottom). -- Marc J. Zeitlin Email: marcz@an.hp.com From: cdenk@ix.netcom.com Date: Mon, 8 Dec 1997 12:13:26 -0600 (CST) Subject: Re: COZY: Chapter 4 Bulkheads (fwd) My insstrument panel is 1/8" aluminum. The original glass panel is removed except for a 1/4" flange alround. The aluminum is fastened to the flange with numerous 10-32 screws to transfer loads. With more than 500 hours on the installation, including some moderate turbulence at near 1900 lbs gross, there is no indication of problems. If I was going to do it again, I might use slightly thinner aluminum. The aluminum goes from fuselage side to side and from leg holes up to the panel cover. It is almost solid holes with instruments as close together as possible. by post.larc.nasa.gov (8.8.6.1/pohub4.2) with SMTP id JAA12171; Tue, 9 Dec 1997 09:52:23 -0500 (EST) Date: Tue, 09 Dec 1997 09:39:03 -0500 From: Paul Krasa Subject: Re: COZY: Chapter 4 Bulkheads (fwd) > >>Can we destroy the structural integrity of the airframe by installing too >>many instruments on the instrument panel? > >This is the least of your worries :-). > >>....... I would think that each hole >>drilled into the panel would make the panel a little weaker. > >It does, but you'd have to have no material at all between the >instruments and/or between the instruments and the top/bottom of the >panel before it would matter. Also, you'd have to destroy the >stiffeners (both top and bottom). > >-- >Marc J. Zeitlin Email: marcz@an.hp.com > I agree with Marc. Most canards have instrument panels that look like swiss cheese. The panel is very flimsy until the instruments are installed. With the instruments in the panel is stiff again. There are a number of Long EZ flying with AL instrument panels mounted on with screws thus effectively, any structural strength of the panel has been negated. Paul Krasa Long EZ 214LP Date: Mon, 29 Dec 1997 14:26:17 -0600 From: "Joseph H. Hart IV" Subject: COZY: Chap. 4, Fig. 5 Well, I am now the proud owner of plans no. MK-648 and plan on building the bulkheads next month. In reading over Chap. 4, I am having trouble understanding Fig. 5 on page 1---I'm a real dumbass, huh? I can't seem to reconcile the cross-section A-A with the other drawing in Fig. 5. I checked the archives and failed to locate an answer. In the upper drawing, both the upper and lower layups have one end that goes up (or down) the bevel and attaches to the layup of the other side. In the cross-section, it appears that the front is a flat layup and the back is the layup that goes up bevels on both ends to meet with the front, flat layup. Is the cross-section incorrectly drawn or am I dense and missing something? Thanks in advance. Jody Hart jodyhart@communique.net MK-648 Date: Mon, 29 Dec 1997 15:59:50 -0500 From: bil kleb Organization: NASA Langley Research Center Subject: Re: COZY: Chap. 4, Fig. 5 Joseph H. Hart IV wrote: > > Well, I am now the proud owner of plans no. MK-648 and plan on > building the bulkheads next month. excellent news! > In reading over Chap. 4, I am having trouble understanding Fig. 5 ... > Is the cross-section incorrectly drawn? not really, no. as with everything else, just read, read, read, and read again ;) reading ahead will usually make the pieces fit together a little smoother...e.g., see figures 3, 5, and 7 on pages 1 and 2 of chapter 6. here is a muttled attempt at explaining figure 5, chapter 4: the top drawing shows a cross section of the seatback as seen from the side. the beveled edge on the left will be the top edge of the seat when it is installed in the airframe and the beveled edge on the right will be joined to the bottom. the top surface is the backside and the bottom surface is the front. the lower drawing shows a section of the seat as if you were looking in the plane of the seatback from the top (or bottom---it really doesn't matter) of the airframe when the seatback is installed in the plane. the left and right edges in this drawing are the port and starboard sides of the seatback. -- bil