Date: Tue, 21 Jan 1997 09:18:50 -0500 From: william l kleb Organization: NASA Langley Research Center Subject: COZY: chap 8: rear heat duct seatbelt attach tube the plans say to do a 7 ply uni layup, centered over the seatbelt attach tube on the rear heat duct (as was done in chap 6 for the front). however, in this case, the tube is only 6 inches ahead of the hole for the square-to-round transition piece and the 7 ply layup is 24 inches long... so what does one do with the extra 6 inches that hangs off the back end of the heat duct when you center the 24 inch long piece over the seatbelt attach tube? bil Date: Tue, 21 Jan 1997 13:07:24 -0500 From: Phillip.Johnson@kan.lmcda.lmco.com (Phillip Johnson) Subject: COZY: chap 8: rear heat duct seatbelt attach tube Bill Kleb writes: > so what does one do with the extra 6 inches that hangs > off the back end of the heat duct when you centre the 24 inch long > piece over the seatbelt attach tube? Bill unless I am misunderstanding you, you have the lay-up going the wrong way. The 24 inch lay-up goes across the heat duct and onto the floor. Your description has the 24 inch lay-up running down the length of the heat duct. This would not be strong enough if this is the case. Same applies to the front seat belt attach point. Phillip Johnson From: Marc J. Zeitlin Subject: COZY: chap 8: rear heat duct seatbelt attach tube (fwd) Date: Tue, 21 Jan 97 14:18:39 EST Phillip Johnson replied: > > Bill Kleb writes: > > > so what does one do with the extra 6 inches that hangs > > off the back end of the heat duct when you centre the 24 inch long > > piece over the seatbelt attach tube? > > Bill unless I am misunderstanding you, you have the lay-up going the > wrong way. The 24 inch lay-up goes across the heat duct and onto the > floor. Your description has the 24 inch lay-up running down the > length of the heat duct. This would not be strong enough if this is > the case. Same applies to the front seat belt attach point. If I remember correctly, there were two of these reinforcing layups. There's one longitudinal one (the 7 ply UNI) that goes on the top of the heat duct. I don't remember the length, but I also don't remember it hanging off the end of the heat duct too far. The second (BID) layup is the 24" long one that Phillip refers to that goes _across_ the seat belt attach, down the sides of the heat duct, and onto the floor of the fuselage. Does this help? -- Marc J. Zeitlin Email: marcz@an.hp.com Date: Wed, 22 Jan 1997 07:16:11 -0500 From: william l kleb Organization: NASA Langley Research Center Subject: Re: COZY: chap 8: rear heat duct seatbelt attach tube Marc J. Zeitlin wrote: > > If I remember correctly, there were two of these reinforcing layups. exactly. > There's one longitudinal one (the 7 ply UNI) that goes on the top > of the heat duct. I don't remember the length, but I also don't > remember it hanging off the end of the heat duct too far. this is one i am asking about, mine hangs off the back end of the duct by 4", if it were to continue up the 45 deg baffle. it is made by folding a trapezoid that is 24" wide at the base and 5" wide at the top, so you end up with a piece that is 24" long. this piece is supposed to be centered on the rear seatbelt attach tube, i.e., 12" either side of the tube. however, the seat belt attach tube is only 8-3/4" ahead of the forward landing gear bulkhead; and by the time you cut out the hole for the transition tube and account for the 45 deg baffle area, you only have about 5" of duct-top left for the rear 12" half of this 7 ply layup... the text says that you are supposed to do this layup before you make the transition piece, but figure 16 shows the layup extending onto the transition piece. (?) either way, you only have about 5" of load-carrying glass in the back which seems like the most important load path direction. i guess this is just another hint that you should not load toward the aft cg, i.e., the rear seat passengers better light because otherwise the center seatbelt attach point will fail... > The second (BID) layup is the 24" long one that Phillip refers > to that goes _across_ the seat belt attach, down the sides of > the heat duct, and onto the floor of the fuselage. right, except its an alternating uni/bid combination. i don't know about the 24" bit, it just says to make it ~4" wide and extend ~6" on either side of the heat duct, feathering the edges so as to avoid a `bump'. maybe it works out to 24" but i haven't got to those yet. bil From: Marc J. Zeitlin Subject: Re: COZY: chap 8: rear heat duct seatbelt attach tube (fwd) Date: Wed, 22 Jan 97 9:39:49 EST bil kleb writes; >the text says that you are supposed to do this layup before >you make the transition piece, but figure 16 shows >the layup extending onto the transition piece. (?) I definitely did mine before the transition piece. >either way, you only have about 5" of load-carrying glass >in the back which seems like the most important >load path direction. Not really. There's almost no structure tying the heat duct to the LG bulkhead. The (as you correctly said) UNI and BID layup that goes on over the seat belt attach tube area later ties the seat belts to the fuselage floor. I believe that this is the main load path for seat belt loads. I believe the first (UNI folded triangle) layup is there to act as a transition load path for the stress on the small cross-wise oriented tube to the cross-wise oriented 2nd layup. If the first UNI layup wasn't there, there would be nothing to spread the load over the full 4" width of the 2nd layup in question. -- Marc J. Zeitlin Email: marcz@an.hp.com Date: Wed, 22 Jan 1997 12:38:59 -0500 From: Phillip.Johnson@kan.lmcda.lmco.com (phillip johnson) Subject: Re: COZY: chap 8: rear heat duct seatbelt attach tube Bill Kleb writes: > i think (hope) you have: > there are two sets of lay-ups for the center seatbelt attach tubes. > the first is the 2" wide by 24" long (tapered to 5"), 7 ply uni > lay-up which goes along the top of the heat duct. then, after > covering the heat ducts with 2 plies of bid and flox/taping them to > the floors, they get the 7 ply alternating uni/bid, spanwise lay-ups > of which you speak... I wrote my response to your note when I was away on business with no reference material with me and it was a long time ago that I did mine, I seem to remember doing what you said. I was just concerned that you were putting the crosswise piece in the wrong direction. Phillip Johnson Date: Fri, 24 Jan 1997 10:01:33 -0800 From: wkasty@ix.netcom.com Subject: COZY: Canopy Hinges I just started chapter 8 and floxed on the aft canopy hinge in order to install the screw which is hidden by the shoulder support. After aligning and re-aligning hundreds of times, I came up with my best placement for the hinges. They overlap the inside of the longeron and will need trimming later. By moving them inward (toward BL 0) will I have problems later when building the canopy? Also, has anyone found a better hinge solution? They aren't that offensive on the outside if not sticking out too far, but they are rather do-it-yourselfer looking inside. Besides, the screws and nuts are visible inside under the longeron unless covered with a cloth/leather/? interior. Bill Kastenholz Cozy MKIV #536 wkasty@ix.netcom.com Date: Fri, 24 Jan 1997 10:07:43 -0800 From: wkasty@ix.netcom.com Subject: COZY: Seatbelt Hardware Chapter 8 I have been cutting the seatbelt attachment fittings and don't have the seatbelts themselves. Can someone tell me what size hole, and how much clearance from the inside edge I will need to drill the hole to mount the belt fitting. I believe it will be easier to drill the hole now. Thanks! Bill Kastenholz Cozy MKIV #536 wkasty@ix.netcom.com From: Marc J. Zeitlin Subject: COZY: Seatbelt Hardware Chapter 8 (fwd) Date: Fri, 24 Jan 97 13:26:47 EST Bill Kastenholz writes; >..... Can someone tell me what size hole, and how much >clearance from the inside edge I will need to drill the hole to mount the >belt fitting. If I remember correctly (someone please correct me if I'm wrong!) you use a 1/4 bolt to hold the seat belt to the attach fitting (the aluminum angle bracket). The plans show what's used. The seat belts that I got from Wicks work fine with my bracket hole drilled about in the middle of one of the "L" sides. I just followed the plans for hole placement and size, as well as bracket shape and everything worked out just fine. P.S. Bill - your editor is putting all your text on one line. Please set your editor to insert a line wrap at 72 characters or less. This will make your messages much easier to read. Thanks. -- Marc J. Zeitlin Email: marcz@an.hp.com Date: Mon, 27 Jan 1997 08:36:38 -0500 From: william l kleb Organization: NASA Langley Research Center Subject: COZY: chap 8: shoulder rest as evidenced by some comments in the archives, some people don't like the method of installing the nutplates in the shoulder rest after it is installed (for whatever reason). i happened to be one of those, so i thought i'd pass along what i ended up doing to install these before glassing the shoulder rest to the seatback. 0) i bought a scrap of 3/8" G-10 (1-1/2" x 6") for $5 from one of my local plastics dealers and used it in place of the 6 mm birch plywood / 12 bid plies arrangement.* 1) i installed the hardpoints in the foam, drilled 1/4" holes through the center of the hardpoints, and assembled the shoulder rest foam pieces. 2) i installed the nutplates on rectangles of 0.063" 2024-T3 sheet. the rectangles were the same width as the hardpoint (1-1/4"), but slightly undersize in the other direction to allow room for the micro on the inside corner. thus, the 1/4" holes are not centered on the rectangles. 3) i bolted the nutplates to the G-10 hardpoints with AN4-7A bolts and drilled a #34 hole in each corner of the nutplate to accept #6 x 3/8" panhead sheet metal screws. these screws are for alignment purposes during glassing. 4) i unbolted the nutplates and "car"-waxed the bolts and the inside of the nutplates. then i masked the 1/4" holes and glassed the inside of the shoulder rest. 5) after partial cure, i trimmed the glass and masking tape from the 1/4 holes, floxed the nutplates in place, installed the #6 alignment screws, inserted the AN4-7A bolts, and tightened the bolts until a decent amount of flox squeezed out the sides. 6) i then installed the shoulder rest per plans; and after cure, removed the bolts and masked the 1/4" holes for glassing the outside. as a side note: i accelerated the cure of the inside layup by putting it in my (emptied) garbage can and placing a space heater at the entrance. bil --- *this method is not dependent on the use of G-10. it should work equally well with the plans-specified 6 mm birch plywood also. Date: Sun, 2 Feb 1997 20:37:40 -0800 From: wkasty@ix.netcom.com (william g kastenholz) Subject: COZY: Chapter 8 heatduct question is how do the throttle, mixture, and carbheat control cables get around the transition piece? I don't see any mention in later chapters of any bracket to go around the transition tube. If I need to make space for these control cables I could cock the tube to one side now while I am building it. If I get no response I'll just ignore it and proceed with full faith in the plans. I hope this message came out in normal paragraph form, I couldn't for the life of me find any line-wrap function or editing feature in the Netcomplete software. Bill Kastenholz wkasty@ix.netcom.com Cozy MKIV #536 From: Marc J. Zeitlin Subject: COZY: Chapter 8 heatduct (fwd) Date: Mon, 3 Feb 97 9:37:52 EST Bill Kastenholz wrote; >question is how do the throttle, mixture, and carbheat control cables >get around the transition piece? I don't see any mention in later >chapters of any bracket to go around the transition tube. If I need to >make space for these control cables I could cock the tube to one side >now while I am building it. This is an interesting question. Just yesterday I cut out the foam for the rear heat duct cover, which also covers the transition piece. I didn't think about where the cables, etc. would go. I had to hollow out some of the foam to get the width right as it went around the transition piece. I _believe_ that there's enough room inside this cover (and you can adjust this stuff to make more room if you need it) so that the cables, etc. can travel up and over the transition piece and then go straight back to the firewall. > I hope this message came out in normal paragraph form, I couldn't >for the life of me find any line-wrap function or editing feature in >the Netcomplete software. Worked fine for me, and I usually see problems with this sort of stuff first. Thanks for asking. -- Marc J. Zeitlin Email: marcz@an.hp.com From: Marc J. Zeitlin Subject: COZY: Seat Belt Attach Brackets (fwd) Date: Tue, 10 Jun 97 13:54:59 EDT Larry Schuler writes: > Had trouble finding the bolt hole size and the hole center dimentions > for the belt-end attachment. Maybe I didn't look in the right place. > > Is a 1/4" hole centered on the bracket appropriate? Yes. Maybe just a smidge toward the edge - you want to be sure to have clearance for the bottom of the belt-end metal including the radius at the inside corner of the angle bracket. 1/4" is the correct diameter - it uses AN-4 bolts for the attachment (I'm going from memory here, but I KNOW it's not AN-3's, and I don't believe it was AN-5's - too big). -- Marc J. Zeitlin Email: marcz@an.hp.com From: lschuler@cellular.uscc.com Date: Tue, 10 Jun 97 12:08:57 -0600 Subject: COZY: Seat Belt Attach Brackets Hi all. Been a while since I posted here..... work has both pro's and con's. Pro is it provides $$$ for airplane; con is I'm extreemely busy making the $$$ for the airplane, and food, and morgtage, and.... I am on Chaper 8. Fabricating side seat belt attach brackets. Want to put off buying the belts until later. Had trouble finding the bolt hole size and the hole center dimentions for the belt-end attachment. Maybe I didn't look in the right place. Is a 1/4" hole centered on the bracket appropriate? I could drill these later after I get seat belts (much later), but would rather do it now before Alodining the brackets. Hope to see many of you at Oshkosh. Thanks, Larry Schuler MK-IV-#500; CH-8 slow but sure. lschuler@cellular.uscc.com Date: Tue, 10 Jun 1997 13:32:43 -0600 (MDT) From: Ron Lee Subject: Re: COZY: Seat Belt Attach Brackets (fwd) At 13:54 97/6/10 EDT, you wrote: >Larry Schuler writes: > >> Had trouble finding the bolt hole size and the hole center dimentions >> for the belt-end attachment. Maybe I didn't look in the right place. >> >> Is a 1/4" hole centered on the bracket appropriate? > >Yes. Maybe just a smidge toward the edge - you want to be sure to have >clearance for the bottom of the belt-end metal including the radius at >the inside corner of the angle bracket. > >1/4" is the correct diameter - it uses AN-4 bolts for the attachment (I'm >going from memory here, but I KNOW it's not AN-3's, and I don't believe >it was AN-5's - too big). > >-- >Marc J. Zeitlin Email: marcz@an.hp.com > > I just looked at Ch 8 in my LONG-EZ plans and the seat belt attachment uses an AN4-5A (1/4") bolt. The hole MAY be about 1/16" closer to the edge from center. (in my plans it is 1/8" thick by 1" x 1" aluminum angle). Ron Lee From: lschuler@cellular.uscc.com Date: Tue, 10 Jun 97 15:12:38 -0600 Subject: COZY: Seat Belt Attach Brackets (fwd) --simple boundary Content-Type: text/plain; charset=US-ASCII Content-Transfer-Encoding: 7bit I asked: >> >> Is a 1/4" hole centered on the bracket appropriate? Marc wrote: >Yes. Maybe just a smidge toward the edge - you want to be sure to have >clearance for the bottom of the belt-end metal including the radius at >the inside corner of the angle bracket. Agree; the interference concern is why I am stumped without a belt-end to measure. But, doesn't the belt-end go outside the bracket? If so, the inside radius of the bracket wouldn't matter; fuselage hardpoint would be the concern for interference. Could be I looked at the drawing wrong though..... Maybe someone could measure the distance from center of the belt-end hole to the edge on a "stock" belt-end? I'd appreciate it. Also, while I'm thinking of it Marc, your notes indicate you floxed over the bolt heads on the outside of the fuselage. Plans don't call for this (at least at this point); just to counterbore so the head is flush with the fuselage. Did you make flats on the heads first? Or, would it be safe to assume I would never need to remove (and re-attach) the brackets at some point? I thought about floxing as you did, but I'd hate to have one spin under the flox... Is it just a few chapters down the road that call for the flox (ie. finishing)? Larry 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 homer.uscc.com by cellular.uscc.com (ccMail Link to SMTP R8.00.00) ; Tue, 10 Jun 97 13:43:24 -0600 Return-Path: Received: from www.uscc.com. (ns.uscc.com [204.179.101.2]) by homer.uscc.com with ESMTP id OAA13345 for ; Tue, 10 Jun 1997 14:31:58 -0400 (EDT) Received: from palrel1.hp.com (palrel1.hp.com [156.153.255.235]) by www.uscc.com. with ESMTP id OAA00584 for ; Tue, 10 Jun 1997 14:26:44 -0400 (EDT) Received: from hpwarhw.an.hp.com (hpwarhw.an.hp.com [15.57.193.122]) by palrel1.hp.com with SMTP (8.7.5/8.7.3) id KAA26292 for ; Tue, 10 Jun 1997 10:56:34 -0700 (PDT) Received: by hpwarhw.an.hp.com (1.37.109.8/15.5+IOS 3.22) id AA21192; Tue, 10 Jun 1997 13:55:00 -0400 Received: by hpwarhw.an.hp.com (1.37.109.8/15.5+IOS 3.22) id AA21185; Tue, 10 Jun 1997 13:54:59 -0400 From: "Marc J. Zeitlin" Message-Id: <9706101754.AA21185@hpwarhw.an.hp.com> Subject: COZY: Seat Belt Attach Brackets (fwd) To: cozy_builders@hpwarhw.an.hp.com (Cozy MK-IV Builders) Date: Tue, 10 Jun 97 13:54:59 EDT Mailer: Elm [revision: 70.85] Sender: owner-cozy_builders@hpwarhw.an.hp.com Precedence: bulk Reply-To: "Marc J. Zeitlin" --simple boundary-- Date: Tue, 10 Jun 1997 15:43:54 -0600 (MDT) From: Ron Lee Subject: Re: COZY: Seat Belt Attach Brackets >my long-ez supplied belts are as follows: > >hole in end is 5/16" diameter. > >Distance from outer (away from webbing) hole to edge of metal >is 7/32", thus center of hole to metal edge is 3/8". > >angle up (towards webbing of the metal that is attached to the >hardpoint is about 30 degrees (eyeballed). > >My long-ez plans show the metal tab on the INSIDE of the angle. > >Your Cozy might be different. > >Ron Lee > This raises the now obvious question. The plans call for a 1/4" bolt to secure these belts. Would it not be appropriate practice to use a bolt that is the same diameter as the hole in the belt metal piece instead of a slightly smaller one (5/16' vs 1/4") ? Ron Lee From: lschuler@cellular.uscc.com Date: Tue, 10 Jun 97 17:01:33 -0600 Subject: Re: COZY: Seat Belt Attach Brackets --simple boundary Content-Type: text/plain; charset=US-ASCII Content-Transfer-Encoding: 7bit Ron Lee wrote: >>my long-ez supplied belts are as follows: >> >>hole in end is 5/16" diameter. SNIP >This raises the now obvious question. The plans call for a 1/4" >bolt to secure these belts. Would it not be appropriate practice >to use a bolt that is the same diameter as the hole in the belt >metal piece instead of a slightly smaller one (5/16' vs 1/4") ? >Ron Lee Or use a bushing.... Larry 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 homer.uscc.com by cellular.uscc.com (ccMail Link to SMTP R8.00.00) ; Tue, 10 Jun 97 16:56:10 -0600 Return-Path: Received: from www.uscc.com. (ns.uscc.com [204.179.101.2]) by homer.uscc.com with ESMTP id RAA13957 for ; Tue, 10 Jun 1997 17:44:45 -0400 (EDT) Received: from palrel1.hp.com (palrel1.hp.com [156.153.255.235]) by www.uscc.com. with ESMTP id RAA01014 for ; Tue, 10 Jun 1997 17:39:29 -0400 (EDT) Received: from hpwarhw.an.hp.com (hpwarhw.an.hp.com [15.57.193.122]) by palrel1.hp.com with SMTP (8.7.5/8.7.3) id OAA05782 for ; Tue, 10 Jun 1997 14:53:06 -0700 (PDT) Received: by hpwarhw.an.hp.com (1.37.109.8/15.5+IOS 3.22) id AA27252; Tue, 10 Jun 1997 17:51:43 -0400 Received: from relay.hp.com by hpwarhw.an.hp.com with SMTP (1.37.109.8/15.5+IOS 3.22) id AA27247; Tue, 10 Jun 1997 17:51:40 -0400 Received: from jerry.pcisys.net by relay.hp.com with ESMTP (1.37.109.16/15.5+ECS 3.3) id AA094589459; Tue, 10 Jun 1997 14:50:59 -0700 Received: from estelle169.pcisys.net (estelle169.pcisys.net [207.76.102.169]) by jerry.pcisys.net (8.8.5/8.8.5) with SMTP id PAA07409 for ; Tue, 10 Jun 1997 15:43:54 -0600 (MDT) Date: Tue, 10 Jun 1997 15:43:54 -0600 (MDT) Message-Id: <199706102143.PAA07409@jerry.pcisys.net> X-Sender: ronlee@pcisys.net X-Mailer: Windows Eudora Light Version 1.5.2 Mime-Version: 1.0 Content-Type: text/plain; charset="us-ascii" To: cozy_builders@hpwarhw.an.hp.com From: Ron Lee Subject: Re: COZY: Seat Belt Attach Brackets Sender: owner-cozy_builders@hpwarhw.an.hp.com Precedence: bulk Reply-To: Ron Lee --simple boundary-- From: Marc J. Zeitlin Subject: COZY: Seat Belt Attach Brackets (fwd) Date: Wed, 11 Jun 97 9:46:49 EDT Larry Schuler wrote: > Maybe someone could measure the distance from center of the belt-end > hole to the edge on a "stock" belt-end? I'd appreciate it. Dang, I meant to check it last night - I forgot. I'll write myself a note. > Also, while I'm thinking of it Marc, your notes indicate you floxed > over the bolt heads on the outside of the fuselage. Plans don't call > for this (at least at this point); just to counterbore so the head is > flush with the fuselage. I can't imagine that I did something not called out in the plans - I'll check this tonight too:-), and try and find the place in the plans that calls it out. > ..... Did you make flats on the heads first? No. > ..... would it be safe to assume I would never need to remove (and > re-attach) the brackets at some point? According to the plans (as I remember them from 2 years ago) you flox the bracket in place, install the two screws, and then flox their heads in. I'd venture a guess that Nat doesn't ever expect you to have to take this apart :-). -- Marc J. Zeitlin Email: marcz@an.hp.com Date: Wed, 11 Jun 1997 10:17:29 -0400 From: wilhelmson@scra.org Subject: Re[2]: COZY: Seat Belt Attach Brackets The seat belt attachment requires a bushing that is longer than the belt attach bracket is thick. This allows the bolt to be torqued and still lets the bracket rotate so that the belt aligns properly. I did this ten years ago, but the conversation brought back the old memory. I am not sure this is in plans, but it is the way everyone ends up doing it. Date: Wed, 11 Jun 1997 11:23:42 -0400 (EDT) From: Pmsunset@aol.com Subject: COZY: Re: Seat Belt attach bracket Mr. Wilhemson writes: >The seat belt attachment requires a bushing that is longer > than the belt attach bracket is thick. This allows the bolt >belt aligns properly. I did this ten years ago, but the >conversation brought back the old memory. I am not sure this >is in plans, but it is the way everyone ends up doing it. >From personal experience, the above is really the only correct way to do this. The seat belt attach fitting must be free to rotate on the bushing. Long story, but a few years back, I hit the ground in a nose down attitude. The seat belts had been installed by an A&P a few years prior to this. He caught a lot of grief from the Feds for tightening down the belt attach to where it could not articulate. The belt end attachment broke from the bolt hole across. In a scene reminiscent from "Gunsmoke" days where Doc is loudly dropping bullets probed out of the victim in a metal pan, I found myself. The "Doc" probing pieces of my eyeglasses, various toggle switch handles, etc. out of my face.... which had impaled itself on the instrument panel toggle switches. The above (barring getting flamed too much) could greatly influence the safety layout of an instrument panel, crash-absorbing seat structures (besides your spine), etc. Of course, this will never happen to any of us, but.... Maybe this will save 63 sutures, Eddie Date: Wed, 11 Jun 1997 11:54:18 -0600 (MDT) From: Ron Lee Subject: Re: COZY: Re: Seat Belt attach bracket At 11:23 97/6/11 -0400, you wrote: >Mr. Wilhemson writes: >>The seat belt attachment requires a bushing that is longer >> than the belt attach bracket is thick. This allows the bolt >>belt aligns properly. I did this ten years ago, but the >>conversation brought back the old memory. I am not sure this >>is in plans, but it is the way everyone ends up doing it. > >>From personal experience, the above is really the only correct way to do >this. The seat belt attach fitting must be free to rotate on the bushing. >Eddie > Could someone elaborate on the length of the bushing. In my case the OD would be 5/16" and the ID 1/4". With 1/8" bracket, would you make it "about" 1/4" long or longer? Oops, forgot to add the thickness of the seat belt tab. Bottom line, about how much more than the combined thickness of the seat belt tab and attach bracket (In my case that it 1/4") Ron Lee From: Marc J. Zeitlin Subject: COZY: Seat Belt Attach Brackets Date: Fri, 13 Jun 97 9:50:27 EDT People; OK, hopefully I can put this stupid seat belt issue to bed, after finally making some measurements and checking my belts this morning. Larry Schuler wrote: >> Maybe someone could measure the distance from center of the belt-end >> hole to the edge on a "stock" belt-end? I'd appreciate it. I bought the recommended belts from Wicks. The hole for the bolts in the belt-end tab is 3/8" diameter, and the CENTER of the hole is ~0.46" from the closest edge. I put my holes in the angle brackets pretty much dead center on the 1" leg, as the tab does go on the flat side (not the side with the internal corner, as I had previously incorrectly stated). The tab is shaped like this: --------------------------- --- ------------- --- --- --- --- O --- --- --- --- Imagine the "O" is the 3/8" diameter hole, and the bottom is the closest edge. The tab is 3/32" thick chromed steel. As stated, bushings are necessary to ensure free rotation of the tab, however each Wicks supplied belt _COME_ with two 5/16" diameter O.D. 1/4" I.D. washers to use for exactly this purpose. The washers are 1/16" thick each, so there's 1/32" free play in the thickness direction when the bolt is clamped down. >> Also, while I'm thinking of it Marc, your notes indicate you floxed >> over the bolt heads on the outside of the fuselage. Plans don't call >> for this (at least at this point); just to counterbore so the head is >> flush with the fuselage. I scoured the plans and could NOT find anywhere that called out what to do with the bolt heads (other than to c'bore them below the surface). So, two years later I have no clue what I was thinking when I did that, other than figuring that I had to fill the c'bores with _something_, and flox was probably stronger than micro :-). As I said in my previous response, the angle brackets are floxed on, as well as bolted, so I don't think they're ever coming off again. -- Marc J. Zeitlin Email: marcz@an.hp.com From: lschuler@cellular.uscc.com Date: Fri, 20 Jun 97 16:57:52 -0600 Subject: COZY: Seat belt fuselage attachements After measuring for proper length bolts for the fuselage side seat belt brackets (I'm a perfectionist), I called Wicks to order the appropriate length MS525 screws. Found that quite a few of the sizes have been discontinued due to lack of supplier. They suggested going with longer screws and using several washers. That would be ok, but I would have needed 4 or 5 washers on a few by using the lengths they had in stock. Thought you all should know about the supply issue. If I remember correctly (didn't look it up), 2 - 3 washers is max recommended in AC repair manuals and at the beginning of the AN hardware section in the Wicks catalog, so I opted for AN4 bolts for three of the brackets (no step). I Just happened to have the right size MS525 screws for the left front (with step). The 5/8" facing bit allows for just enough room to use a thin-wall socket on the bolt head. I also could have drilled deeper with facing bit to allow me to use shorter screws, but that would have reduced the strength of the bottom longeron; not a good idea for safety sake. Strength of the AN4's should be same or better than MS525 and the hex heads will let me sleep better knowing I can check tightness of the nuts during future inspections etc. without worrying about bolts turning in the flox. Just one guys answer.... If anyone sees a good safety reason to NOT use the AN4's; please let me know. Larry Schuler #500 Ch-8 lschuler@cellular.uscc.com Date: Sat, 21 Jun 1997 19:46:06 -0400 (EDT) From: DFinn7971@aol.com Subject: Re: COZY: Seat belt fuselage attachements In a message dated 97-06-20 21:33:11 EDT, lschuler@cellular.uscc.com writes: << They suggested going with longer screws and using several washers. >> Possibly some of the real experts will take exception to this but I would suggest placing two nuts on the longer screw (use them to lock each other into position) at the desired length. You could then saw the screw off to the proper length with a hack saw using the outer nutr as a guide. Unscrewing the nuts will repair any damage to the threads. Dick Finn DFINN7971@AOL.COM Cozy Mark IV #46 Date: Thu, 14 Aug 1997 17:03:35 -0700 (PDT) From: "Mr. Radon" Subject: COZY: Shoulder support harness hardpoints. I've had some time to look over, think over and talkover Nat's method of hardpoint installation on the shoulder support. A good hardpoint should be able to take 50G's in a crash. Your body may be black and blue but as long as the hardpoints hold you should be all right. I didn't want to compramise the strength of the hardpoints by cutting into the support to install the nutplates. Also you only have three layers of glass holding the support to the seatback. Here's my solution: I used a longer hardpoint (2.75") out of G-10, I installed these and then drilled the holes. I then vacume bagged two layers of BID to the inside surface, no over hang. Floxed in a piece of extruded Al angle the entire length of the support (holes pre drilled, nutplates installed). pluged the holes with wax, taped the support to the seatback. Then I applied two ply of BID tape over the hard points and around to the back of the seat back, then applied the top two plys BID over the top. I figure two 170# people can put a lot of force on these four hardpoints, you don't want them ripping out of the foam, anyhow they now make ideal lift locations if needed. Has anyone known of an airframe which has loaded the existing shoulder support design? Roy #503 Chap. 8.6 From: N11TE@aol.com Date: Fri, 15 Aug 1997 09:54:53 -0400 (EDT) Subject: Re: COZY: Shoulder support harness hardpoints. Re: Your concern over strength of sholder support hard points. It was my understanding, by third-hand report, that the sholder hard points had ripped out of the Cozy MK IV that crashed on landing in Florida and killed the two in the front seat while the two passengers lived. I would appreciate more information from someone who has knowledge of this accident. I mentioned this report to Nat shortly after the accident to see if he wanted to review the mounting method but did not get much of a reaction. Nor have I seen any plans changes since then. All I can say is that in my plane I am adding several additional plies of uni over the hard points going both directions and lapping over the back of the seat. Just a personal opinion and personal solution. Tom Ellis N11TE@aol.com Cozy MK IV plans #25 now AeroCanard 540 From: cdenk@ix.netcom.com Date: Sat, 16 Aug 1997 07:57:45 -0500 (CDT) Subject: Re: COZY: Shoulder support harness hardpoints. On 08/15/97 09:54:53 you wrote: > >Re: Your concern over strength of sholder support hard points. > >It was my understanding, by third-hand report, that the sholder hard points >had ripped out of the Cozy MK IV that crashed on landing in Florida and >killed the two in the front seat while the two passengers lived. I would >appreciate more information from someone who has knowledge of this accident. > >I mentioned this report to Nat shortly after the accident to see if he wanted >to review the mounting method but did not get much of a reaction. Nor have I >seen any plans changes since then. > >All I can say is that in my plane I am adding several additional plies of uni >over the hard points going both directions and lapping over the back of the >seat. > >Just a personal opinion and personal solution. > >Tom Ellis >N11TE@aol.com >Cozy MK IV plans #25 >now AeroCanard 540 > > > It may not be that bad to have the attach points fail at some point. The idea is not to suddenly stop, but slow quickly in a controlled fashion, and we're talking in an area that even auto mfg. and NTSA can't figure out what is best. Its OK to hit your head lightly or maybe moderately, and if the attach points fail before doing damage to upper torso, and light damage to cranium, that may not be that bad. Nobody can say if survival (or not)was for this cause or that, with exception not wearing seat belt, get thrown out of vehicle, and then vehicle crushing when rolling on top of vehicle. Also could build aircraft with NASCAR roll cage. What would it weigh?? From: N11TE@aol.com Date: Sat, 16 Aug 1997 13:29:41 -0400 (EDT) Subject: Re: COZY: Shoulder support harness hardpoints. You raise some valid points, Carl, as a good engineer should. There is no question that a full roll cage is impractical and would weigh far to much. And still might not protect one. All designs are compromises we have to live with. Obviously, the proper way to determine the proper mounting method would be destructive testing, as done in th automotive business. After this much work building this plane, frankly I am not willing to do this. I should have gone farther in my original post to state that I had reviewed the number of layers of glass called for in the plans to mount the sholder harness and then looked at the strength of the attachments of the lower seat belt mounts. From this I was somewhat uncomfortable with the comparison. You are very correct in pointing out that in some cases it might be better to have the upper mounts fail first. But, this is the reason I chose a plans-built plane.... so I could make whatever changes I felt would be best for me. I am planning to only add a small amount of additional glass over these hard points. Recognizing that this would add a few more ounces to the plane but not pounds. (Yes, I know these ounces add up.) Also, I did not intend to imply that any additional reinforcement to these hard points would have made any difference in the results of the Florida accident. The purpose of my post was to express my personal concern over one small detail in the building process and to let others know how I was going to address it in my plane. Each builder then can make their own decision about their own plane. Thanks for your response, Carl, obviously someone needs to follow up after me. Tom Ellis N11TE@aol.com Cozy plans #25 now AeroCanard 540 From: SBLANKDDS@aol.com Date: Sat, 16 Aug 1997 22:53:31 -0400 (EDT) Subject: Re: COZY: Shoulder support harness hardpoints. <<<>>> I did not see the wreck, but knew Chuck and miss him. I understood that the plane was very low and slow, ( long final at an unfamiliar airport) with a nose high pitch attitude, and hooked a power line with the main gear just inches below the fuselage. This resulted in the power line pulling off the support poles but not breaking. The Cozy hit nose first, hanging by the wires with the engine still running. The fact that the 2 kids in the back were not killed is a miracle. A stronger shoulder support does not seem to be the solution. Perhaps saftey devices like helicopters use to cut power lines???? Air bags, Or better area familiarization and altitude management. Some mistakes you only get to make once........ My .02c Steve Blank Date: Mon, 18 Aug 1997 18:14:54 -0700 (PDT) From: "Mr. Radon" Subject: Re: COZY: Shoulder support harness hardpoints. > <<< survived>>>> > > A stronger shoulder support does not seem to be the > solution. Perhaps saftey devices like helicopters use to cut power lines???? > Air bags, Or better area familiarization and altitude management. Some > mistakes you only get to make once........ > I've lost a friend too, my local crop duster hit a wire, augered in and died because one of his shoulder harness's webing was inadvertently wraped over a tube. The tube buckled causing enough damage when the plane came to rest he was crushed to death. More then likly the roll cage would have prevented the death, but attention to detail killed him. Now about the shoulder harness attach points. At Boeing we assume 40% of the load in a four point harness is going into the shoulders. With a nominal force of 10G's and a 180# person you have 360# on each shoulder harness. This isn't much but it is what we call shock loading. The way the design calls out a cut to be made just where the structure will fail is bad design and I've told Nat so. The question is, when, not if, I forget to pay attention to detail, my body will be found straped to a seat with no question wether or not reinforcing a seat belt could have saved me. I think Nat needs to change at least the way the nutplates are installed, there is no reason to cut into the layups to install them. Roy MK IV #503 - Chapter 9.1 Date: Thu, 21 Aug 1997 09:40:10 +0200 From: Rego Burger Subject: Re: COZY: Shoulder support harness hardpoints. -Reply Reply to Tom Ellis's ideas on Seat belts. I think making an effort to strengthen them is good! I just feel one must make sure that the accident report is accurate.\ 1.) Did they rip out, or did the bolts sheer off? 2.) By strengthening the mount are we not going to cause the whole seat to be ripped off? 3.) Sometimes, designs are of such a nature that warrants breakage at some point to absorb certain loads. Naturally we all want to survive! The fact that the rear seat passengers survived may be attributed to them being lighter.???? Another point to consider is, if not flying with passengers is to "link" the harness points front to rear with an interconnecting strap and buckle system. You will then have more displacement of restraint. Chew on it :-) Rego Burger Port Elizabeth RSA ( Rep. South Africa ) cozy Mk 4 # 139 http://home.intekom.com/glen/rnb.htm mailto:rnb@intekom.co.za above e-mail = home 041-386113 (W) 041-381757 (H) From: "Nat Puffer" Subject: COZY: Shoulder harness hardpoints Date: Sat, 23 Aug 1997 15:44:54 -0500 In response to the unfounded rumor that the shoulder harness attach points failed in the Florida accident, we have photographs following the crash that show that the shoulder harness attach points and shoulder harnesses were intact and in place after the crash. The front seat occupants died from impact with the ground (the airplane hit the ground vertically nose first at a high rate of speed). Let's not post on internet unfounded rumors. Nat From: N11TE@aol.com Date: Tue, 26 Aug 1997 00:33:54 -0400 (EDT) Subject: COZY: Sholder Harness Hardpoints To: Nat Puffer First of all, Nat, I'm glad to see you respond to the net. I think it would be good for all builders if this medium could be used by you to address specific subjects as required. In this case, I did not read my messages for a couple of days and returned to find quite a number of E-mails from you with the impression given to the cozy builders group that I am personally spreading "unfounded rumors". You even sent an e-mail demanding that I personally respond to you that I received your message! It is not my nature to do anything without making a reasonable investigation of the facts. You should know that as you and I have had several long conversations recently and you are currently flying your plane with a version of the electric nose lift mechanism that I designed. I have no interest in perpetrating "unfounded rumors." While attending Sun 'n Fun after the Florida accident I had a long conversation with another Cozy builder who told several of us (this conversation has been verified by another builder) that he had made a trip over to personally view the wreckage. I was interested in his description and was particularly impressed by the fact that two people had survived. It appeared a real credit to the construction of the plane. This builder volunteered the information that the front sholder support mounts had failed. When a known builder tells me he personally sees something, my first reaction - maybe not correct in this case - would be to assume this is not just an unfounded rumor. Attempting to follow up this input in the proper manner, I brought it to your personal attention when I saw you at the following Oshkosh. You and I discussed it briefly and it was your suggestion that we might want to consider adding a couple extra layers of uni over the hard points. But, I never heard anything more after this. Another builder sent an E-mail to the group expressing his concern over the mounting method of the sholder harness hard points. It was only my intention to reply to his message with the fact that I felt the same way. And to tell him that I was going to add a little more glass to be extra strong. I still plan to do this. I mentioned this accident only because, if it were true that the hard points did pull out, it would be a safety issue that might need to be addressed and could be solved very easily. And, if you read my original post, I stated "I would appreciate more information from someone who has knowledge of this accident." I was asking for a response from someone like yourself, Nat, who could put closure to this issue. I certainly did not mean to imply that any deaths or injuries might have been due to this. Although, in hindsight, I can see how someone might misinterpret what I said. To any who took offense, I apologize. Frankly, rather than leveling "posting of unfounded rumors" charges, it seems to me that this situation is a perfect example of how this forum can be used in a positive manner to get the truth out to a wide audience. If someone has a reasonable question, it should be directed to this forum with a request for response so that someone who has the actual facts can come forward. As you have done in this case. I am curious as to why the original story was told and I will try to contact the individual to see why he told it. Tom Ellis N11TE@aol.com Date: Sun, 26 Oct 1997 20:56:34 -0800 From: marcna Subject: COZY: The Step This is a multi-part message in MIME format. --------------54C0D2A73D286C5CB9FB0EFA Content-Type: text/plain; charset=us-ascii Content-Transfer-Encoding: 7bit I have been fighting with the idea of replacing the Brock step with a retractable one and have finally decided to put in the retractable. I've been thinking of using 1/2 inch square stock as the step sliding into a larger piece of steel square stock. Could anyone who has done this pass along some advice on how they did it. Marc Parmelee N425CZ --------------54C0D2A73D286C5CB9FB0EFA Content-Type: text/x-vcard; charset=us-ascii; name="vcard.vcf" Content-Transfer-Encoding: 7bit Content-Description: Card for Marc Parmelee Content-Disposition: attachment; filename="vcard.vcf" begin: vcard fn: Marc Parmelee n: Parmelee;Marc email;internet: marcna@concentric.net x-mozilla-cpt: ;0 x-mozilla-html: FALSE version: 2.1 end: vcard --------------54C0D2A73D286C5CB9FB0EFA-- From: Marc J. Zeitlin Subject: COZY: The Step (fwd) Date: Mon, 27 Oct 97 10:07:14 EST Marc Parmelee wrote: >I have been fighting with the idea of replacing the Brock step with a >retractable one and have finally decided to put in the retractable. >I've been thinking of using 1/2 inch square stock as the step sliding >into a larger piece of steel square stock. Could anyone who has done >this pass along some advice on how they did it. I put in a round aluminum retractable step (we discussed this a while back, I think) - my calculations showed that for a 4" extension, I needed at least a 5/8" diameter (I went with 3/4" just in case). I don't think the 1/2" square will be adequate - you should do the calculations for different materials to be sure (or else, load a bar with 300 lbs and see what happens). I mounted the rod in a aluminum tube that I glassed to the inside floor of the cabin just in front of the seat belt attach point under the pilot side thigh rest ribs. I cut a slot in the side of the tube, drilled and tapped the rod, and mounted a handle that sticks forward out of the small slot in the instrument panel under the thigh rest. This doesn't work too well - there's too much friction when moving the bar. I'm going to replace the bar with a push pull cable attached to a stub bar mounted to the rod. Actuating the rod very close to the bar attach point moves it very smoothly, so I think this will work OK. -- Marc J. Zeitlin Email: marcz@an.hp.com Date: Mon, 27 Oct 1997 12:19:29 -0500 From: Bulent Subject: Re: COZY: The Step (fwd) I already installed the standard Brock steps and they bother me just looking at them. I am tempted to just cut them off. Wonder if making retractible steps is worth the trouble. I would like to hear from people that already are using them. Thank You. Bulent From: Ken Reiter Date: Mon, 27 Oct 97 11:42:14 CST Subject: Re: COZY: The Step (fwd) Hello Group, I forget when, but Nat had a retract step plan in the Cozy III plan or newsletter in place of the fixed step. I have built it on our plane. Let's see if I can give a brief overview. 1.) At the location of the fixed step, on inside use a wood piece about 5" long to create a flat surface on top of bottom longeron and cover with glass. 2.) Now drill to vert. holes about 4.5" apart through the reinforced bottom longeron sized for AN4 bolt. 3.) Dish out bottom outside area of reinforced longeron. Cover area with release tape and layup ~4 layers bid, open the holes and insert two AN4 bolts length (to size of foot with shoe to clear bottom of fuse.) and cover with ~ 8-10 layers bid. After set, sand to conform to outside curve. 4.) Now remove step and bolts and open holes to fit steel/bronze sleeve so bolts will slide up and down easy and flox sleeves in place. (Make sure glassed step-bolts are inserted until sleeves are setup). 5.) Now place washers and nuts on AN4 bolts and the step will bottom on washer/nut and hold weight. Nat uses bolts with holes and saftey wire between bolts and velcro to hold step up when in flight. Somebody check number of layers to hold weight. PS. Vance has a nice retract step - that is a set of tubes that slides in and out of the fuse. side. Good Luck, Ken From: ponciroli@postoffice.worldnet.att.net Date: Mon, 27 Oct 1997 13:27:01 -0500 Subject: Re: COZY: The Step Marc Parmelee asked if anyone could help him with a retract step. Marc - I called Vance Atkinson for his design, just send him a SASE and he will pop a copy in the mail for you. Send to: Vance Atkinson, 3604 Willomet CT, Bedford, TX 76021-2431. Good Luck Don Ponciroli Date: Mon, 27 Oct 1997 15:29:15 -0500 From: Jim Hocut Subject: Re: COZY: The Step (fwd) I think I'm guilty of starting the discussion a few months back, so feel obligated to relate my experiences. I used a 3/4 inch 2024 Al rod riding inside a 7/8 inch .058 2024 Al tube, and did pretty much what Marc described as far as an actuating mechanism. In addition, I cut slots at a little greater than 90 degrees at the end of the horizontal slot so that it will lock in place in either the retracted or extended position. To aid holding it in place in the retracted position I put an end cap on the interior end of the tube with a short piece of spring to hold the step into the retracted notch (experiementation required). It works great, loose enough to slide easily but yet tight enough that there's no wobble when you stand on it. Jim Hocut jhocut@mindspring.com From: "Fred I. Mahan" Subject: Re: COZY: The Step Date: Tue, 28 Oct 1997 01:46:36 -0500 Marc-- The October 1994 Central States Newsletter, on pgs 19-21, had drawings and instructions for making the T-38 style Jim Voss pull out and drop down aluminum retracting step. Fred in Florida ---------- > From: marcna > To: Cozy Builders Group > Subject: COZY: The Step > Date: Sunday, October 26, 1997 11:56 PM > > I have been fighting with the idea of replacing the Brock step with a > retractable one and have finally decided to put in the retractable. > I've been thinking of using 1/2 inch square stock as the step sliding > into a larger piece of steel square stock. Could anyone who has done > this pass along some advice on how they did it. > > > Marc Parmelee > N425CZ > From: DFinn7971@aol.com Date: Tue, 28 Oct 1997 16:31:37 -0500 (EST) Subject: Re: COZY: The Step (fwd) In a message dated 97-10-27 12:52:02 EST, ken@quickturn.com writes: << PS. Vance has a nice retract step - that is a set of tubes that slides in and out of the fuse. side. >> Jeff Russell also has a retractable step. I haven't installed it yet but it basically fits behind the instrument panel and extends downward instead of outward. This might help some shorter people trying to step up. Dick Finn Date: Thu, 18 Dec 1997 07:04:01 -0600 From: timothy@directcon.net (Tim Sullivan) Subject: COZY: Retractable step Does anyone have the plans (10/94 issue), mention below, scanned? If so can they email them to me? I would appreciate it. Or if your close by, my fax number is 530 295-1683. As you can see I have Terry's permission. My new years resolution is to get back to building the plane after an 18 month pause. This would be a *step* in the right direction :) Thanks. L8tr. > >On Wed, 17 Dec 1997 10:06:07 -0800 Timothy >writes: >>you have an issue that explains how to install a step that retracts >>into >>the fuselage. Unfortunately I started CSA after that issue. How can >>I >>get a hold of it? I believe someone in the cozy group has that issue >>and is will to send it to me but I need your permission first. > >****** > >No problem. Go for it. If he doesn't have it tell me what issue & Page >& it is and I'll Xerox it for you. > >Terry > Tim Sullivan Placerville CA | * | Cozy MK IV Builder #470 |-----(/)-----| The journey began 8/10/95 / \ Current Status: Ch 9 o o