From: "Ian Martin" Subject: COZY: Cozy:LWX Angle Date: Mon, 19 Jan 1998 08:42:54 -0800 Hello fellow Builders, Does anyone know if the angle that the LWX set relative at is critical ? What is this piece used for; just the rearseat back or is the landing gear dependent upon the angle. I need to change the angle by a couple of degrees to take into account my deeper fuselage sides. Thanks for your help. Ian ------------------------------------------------------------------------------- J. Ian Martin Phone: (619) 874 - 7000 x184 email: imartin@gstone.com From: Marc J. Zeitlin Subject: COZY: Cozy:LWX Angle (fwd) Date: Mon, 19 Jan 98 11:58:51 EST Ian Martin wrote: > Does anyone know if the angle that the LWX set relative at is > critical ? > What is this piece used for; just the rearseat back or is the > landing gear dependent upon the angle. I need to change the angle by a > couple of degrees to take into account my deeper fuselage sides. The hardpoints of the Landing Gear are in the lower front LGB and the rear LGB. The angle of the upper front LGB determines the seat angle. A couple of degrees one way or the other on this shouldn't matter structurally, however you want to make sure that you'll still have the tie-in to the main spar, fuselage bottom and LGB's. Make sure that your lower front LGB is EXACTLY as called out distance-wise from the rear LGB, or you'll have a hell of a time fitting your gear legs later on in Chapter 9. My $0.02. -- Marc J. Zeitlin Email: marcz@an.hp.com From: cdenk@ix.netcom.com Date: Mon, 19 Jan 1998 11:24:39 -0600 (CST) Subject: Re: COZY: Cozy:LWX Angle Ian Martin writes angle not critical, but make sure the edge distance (edge of wood to bolt centerline) of bolts is not compromised. Possibly the Faa standard practices (wood airplane section) would be help. Idea is to have enough strength that bolt doesn't split out side. From: "Ian Martin" Subject: RE: COZY: Cutting the fuselage sides square - how ? Date: Thu, 5 Feb 1998 12:33:46 -0800 Hello fellow builders, For those who have successfully completed chapter 5 how did you complete the squaring cuts of the fuselage sides? One of the last steps is to cut the fore & aft edges perpendicular to the longerons and the work bench. Since we are dealing with a curved surface achieving a perfect cut is not obvious to me. My current approach is to set up a jig for a router then by varying the depth I should eventually get all of it. This is complicated by having to do each side separately. Any suggestions are welcome. Thanks for your advice. ++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++ J. Ian Martin imartin@gstone.com (619) 874 - 7000 x184 +++++++++++++++++++++++++++++++++++++++++++++++++++++++++++ From: Fritzx2@aol.com Date: Thu, 5 Feb 1998 17:09:25 EST Subject: Re: COZY: Cutting the fuselage sides square - how ? Ian Martin wrote: > For those who have successfully completed chapter 5 how did you > complete the squaring cuts of the fuselage sides? One of the last steps is > to cut the fore & aft edges perpendicular to the longerons and the work bench. > Since we are dealing with a curved surface achieving a perfect cut is not > obvious to me. Here's what I did. With a square lying on the top of the longeron, and down the front inside fiberglassed surface of the sides, mark a line down front of the sides. After the sides are popped loose from the molds, slide the sides up so that an inch or so hangs over the mold. Then, using a square across the table and up across the sides, cut along the line using a fine tooth hand saw so that the saw blade is parallel to the square placed against the sides. It is more important that the line down the front of the sides be perpendicular to the longeron than the cut be perpendicular to the workbence (within reason) since the cut is made on a thin section on the front and when the front gets matted to F22, lots of flox is involved. I repeated the same procedure for the back cut. It is better to leave a little more than 101.75 (I think that is the magic number that has been burned into my head) so that you can adjust for any slighly out of straight on the top longeron and other tolerances that become apparent when you mate the bulkheads to the sides. It is a whole lot easier to sand a little off then it is to add a little to meet the 101.75 dimension and also have the firewall and F22 square to the top longerons. John Fritz fritzx2@aol.com From: Cozy7971@aol.com Date: Thu, 5 Feb 1998 17:09:26 EST Subject: Re: COZY: Cutting the fuselage sides square - how ? In a message dated 98-02-05 15:38:02 EST, imartin@indy3.gstone.com writes: << One of the last steps is to cut the fore & aft edges perpendicular to the longerons and the work bench. Since we are dealing with a curved surface achieving a perfect cut is not obvious to me. >> Its been a while since I did this but as I remember it I used a carpenters square to align a straight edge acorss both sides (in the forms) perpendicular to the longerons. I clamped the straightedge in place using spring clamps. I then used a combination square (using the bubble to keep the blade vertical) to mark points directly under the straight edge. I connected the dots with a plastic (flexible) ruler and used a saber saw to cut the end off. I left about 1/8 inch slop and used a long sanding block to trim to the exact length. Remeber not to trim the longerons short. They need to extend through the holes in the firewall. Date: Thu, 02 Apr 1998 17:48:51 -0600 From: Darren DeLoach Subject: Re: COZY: Ch 5 Help >1. The plans call for "dishing" a 2" x 7" area for the fuel gauges. > I plan to use the Vance Atkinson gauges but they have not arrived yet. > Do I still need to dish this area before glassing and if so do I use > the same dimemsions or are they different? See the Chap 5 FAQ on Marc's web site about this. Also review the archives for Chap. 5 in 1995-1997. Yes, you dish, but you have some choice about the exact shape (flush or canted). > >2. When making the conduit cover the plans are rather confusing and list > only a width (1.25) and height (.7) but not a length. See the Chap 5 FAQ on Marc's web site, then review the archives for Chap. 5 in 1995-1997. The bottom line is that since your bevel down throught the white foam, and since the bevel can be any location within a wide range of places, then the cover length will depend on where you located the bevel. The FAQ gives a good location for the bevel, it worked fine for me. >Scott Cashel >Arlington, TX > BTW, I live in Bonham, about 35 miles NE of McKinney. I'm halfway through Chapter 6, so I'm not too far ahead of you. -- Darren DeLoach Sales & Software http://www.deloach.com From: Cozy7971 Date: Thu, 2 Apr 1998 21:38:49 EST Subject: Re: COZY: Ch 5 Help In a message dated 98-04-02 16:56:26 EST, kj5me@ix.netcom.com writes: << 1. The plans call for "dishing" a 2" x 7" area for the fuel gauges. I plan to use the Vance Atkinson gauges but they have not arrived yet. Do I still need to dish this area before glassing and if so do I use the same dimemsions or are they different? >> I carved out the foam in that area as you need a solid place to drill the two holes through to allow the gas to enter the fuel guages. From: kj5me@ix.netcom.com Date: Thu, 2 Apr 1998 15:45:58 -0600 (CST) Subject: COZY: Ch 5 Help Greetings to the Group; I am working on Ch 5 and I have two questions. 1. The plans call for "dishing" a 2" x 7" area for the fuel gauges. I plan to use the Vance Atkinson gauges but they have not arrived yet. Do I still need to dish this area before glassing and if so do I use the same dimemsions or are they different? 2. When making the conduit cover the plans are rather confusing and list only a width (1.25) and height (.7) but not a length. Any help here would be greatly appreciated. Thanks in Advance Scott Cashel Arlington, TX Cozy Mk IV #664 From: "L. Wayne Hicks" Subject: COZY: Report: Finishing up Chapter 5 Date: Thu, 30 Jul 1998 09:59:10 -0400 Cozy Gang: Finished Chapter 5 last night and I am looking forward to assembling. I followed the plans exactly with the exception of fuselage jigs. Not wanting to face the prospect of repairing/filling holes left from the 5-minute glue, I used dry-wall screws to hold the foam sides to the masonite. Here's how I did it: 1. After cutting the masonite, I drilled a series of small holes, checkerboard style, one every 18 inches or so. I also drilled holes on the perimeter every 6 inches or so. 2. I mounted the FJA's through FJE's onto 1-inch pine stringers instead of gluing them straight to the table. I then made "jig boxes" by attaching 5-inch pine boards 16 inches wide between the top jigs and the bottom jigs on the ends. In this manner, I had two jig boxes that I could bolt onto the table or unbolt and remove from the table at will. 3. With the jigs being supported off the edge of the table, I put the foam sides onto the top of the jig, then screwed in the drywall screws from the underside of the masonite. (I had tried double-sided carpet tape, but the foam didn' stick...) 4. I used longer drywall screws around the perimeter to hold down the micro'd foam spacers, and later the lower longerons. (Worked a lot better than the nails. Didn't need any clamps!!) Was it worth the effort? YES! When I released the sides from the jigs, there were no holes or torn foam of any kind (at least not from the dry-wall screws... :-) ). No repairs. The holes left from the dry-wall screws are so small that there's really nothing there to fill. And it didn't take but maybe 30 minutes longer to set up the jigs. 30 minutes seems like a good investment of time when one considers the amount of time needed to fill gouges from the 5-minute foam, not to mention the fill and sand, finishing work needed 4 years (??) from now on the exterior layups. (I know, I know...some of you out there were lucky enough not to have problems with the 5-minute glue method. My hat's off to you!) What I really liked was the convenience of being able to move the jigs to and from the table. Made clean-up work and sanding work a breeze. One picky observation: (said in the most cynical, but humorous gesture possible...) Who in the hell came up with the idea of the 4-UND layup on the upper longerons????? Those 4-UND longeron layups certainly qualify as cruel and unusual punishment. :-) I'll be in Los Angeles (Pasadena, actually) from August 1 though August 4. I'd still like to get that Cozy ride.... Wayne Hicks SpaceTec, Inc. Date: Mon, 19 Oct 1998 20:28:12 -0700 (PDT) From: Mark Loy Subject: COZY: Chapter 5 Hi to all! First off, sorry I couldn't make it to the fly-in at SBY. I was really looking forward to meeting everyone and chatting. Second, I found that by using double-sided tape on the forms to hold the fuselage foam down works pretty darn good. I used the type that is used for golf club grips. The tape peels right off the foam with little or no effect to the foam and it held fine during the layup. My layup came up quite good with no defects eventhough I used the wrong precut piece of UND initially. UGH! Hope all is well with everyone and a 'GET-WELL' to Nat is extended. I know all too well about back problems and I would not wish them on my worst enemy! Mark Loy Mk IV #0712 _________________________________________________________ DO YOU YAHOO!? Get your free @yahoo.com address at http://mail.yahoo.com From: Fritzx2@aol.com Date: Sun, 18 Oct 1998 11:13:55 EDT Subject: Fwd: COZY: Trimming Fuselage Sides Joseph Hart wrote, > I'm just about to the point of trimming the fuselage sides. > According to the instructions, you are supposed to trim the forward end > of the sides first. My interpretation of the plans indicates that the > 5.5" x 8.7" cut-out area for the centersection spar is a critical > dimesion such that it makes sense to trim the aft end of the fuselage > sides first in order to ensure that the cut-out dimensions are > preserved. Alternatively, I suppose one could trim the forward end > first and, if necessary, trim into LWX a bit (1/8" or so). This > alternative seems to be less desirable than trimming the aft end first. > Am I missing something here? Is the cut-out dimension as critical as I > interpret it to be? Although it's certainly not obvious at the fuse ends trimming phase, I found that the critical dimension was the height between the edge of the bottom longeron to the top of the front Landing Gear BulkHead when the front LGBH is installed at its proper fuselage station which is 8" in front of the aft LGBH which is 5" in front of the firewall. This is because the front top LGBH has to fit on the bottom front LGBH at an approx. 45 degree angle and if you trimmed too much off the back, then the front LGBH when matted to the fuse sides sticks up too high on the LWX to allow the top LGBH to fit. The plans say that you can trim up to a 1/4" (memory?) off the top of the front bottom LGBH to make the top front LGBH fit but in doing so you might not have enough room to mount the plates for the main gear because there is not enough distance between the main gear mounting hole and the intersection of the top and bottom front LGBH on the aft side. In short, as you slide the firewall, aft LGBH, front LGBH forward as the result of trimming the aft, the allowable height between the bottom longeron and the LWX at the FS where you place your front LGBH continues to reduce since the LWX is at an angle. Keep this in mind as you trim. If accommodating the front LGBH causes the 5.5 dim to be too short, then just trim an 1/8" or so as you mentioned. Hope this is clear enough to help. John Fritz fritzx2@aol.com Return-Path: Received: from rly-zc05.mx.aol.com (rly-zc05.mail.aol.com [172.31.33.5]) by air-zc02.mail.aol.com (v50.21) with SMTP; Sun, 18 Oct 1998 03:57:55 -0400 Received: from twc2.betaweb.com (betaweb.com [206.43.209.18]) by rly-zc05.mx.aol.com (8.8.8/8.8.5/AOL-4.0.0) with ESMTP id DAA01638; Sun, 18 Oct 1998 03:57:49 -0400 (EDT) Received: (from majordomo@localhost) by twc2.betaweb.com (8.8.5/8.8.5) id DAA18024 for cozy_builders-list; Sun, 18 Oct 1998 03:48:44 -0400 X-Authentication-Warning: twc2.betaweb.com: majordomo set sender to owner-cozy_builders@betaweb.com using -f Received: from sakaki.communique.net (sakaki.communique.net [204.27.64.202]) by twc2.betaweb.com (8.8.5/8.8.5) with ESMTP id DAA18019 for ; Sun, 18 Oct 1998 03:48:41 -0400 Received: from communique.net (ppp-204-0-253-67.ne.communique.net [204.0.253.67]) by sakaki.communique.net (8.8.8/8.8.8) with ESMTP id CAA15690 for ; Sun, 18 Oct 1998 02:51:31 -0500 (CDT) Message-ID: <36299DFD.2CCFBDA9@communique.net> Date: Sun, 18 Oct 1998 02:51:26 -0500 From: "Joseph H. Hart IV" X-Mailer: Mozilla 4.05 [en] (Win95; U) To: "cozy_builders@canard.com" Subject: COZY: Trimming Fuselage Sides Sender: owner-cozy_builders@betaweb.com Precedence: bulk Reply-To: "Joseph H. Hart IV" Mime-Version: 1.0 Content-type: text/plain; charset=US-ASCII Content-transfer-encoding: 7bit I'm just about to the point of trimming the fuselage sides. According to the instructions, you are supposed to trim the forward end of the sides first. My interpretation of the plans indicates that the 5.5" x 8.7" cut-out area for the centersection spar is a critical dimesion such that it makes sense to trim the aft end of the fuselage sides first in order to ensure that the cut-out dimensions are preserved. Alternatively, I suppose one could trim the forward end first and, if necessary, trim into LWX a bit (1/8" or so). This alternative seems to be less desirable than trimming the aft end first. Am I missing something here? Is the cut-out dimension as critical as I interpret it to be? Thanks in advance for any insight. Jody Hart New Orleans, LA Cozy Mark IV plans no. 648 Chapter 5, see progress at: home.gs.verio.net/~jodyhart/home.html N359JH (reserved) Date: Sun, 08 Nov 1998 22:44:27 -0600 From: "Joseph H. Hart IV" Subject: COZY: Two Fuselage Assembly Questions I am starting Chapter 6, Fuselage assembly and have run into two problems: (1) Because of how I placed my aft longeron doublers, my fuselage sides turned out to be 1/8" short. I assume that, as long as everything is level/plumb and even side to side, up/down and fore/aft that a 1/8" deviation in the fuselage sides is within the margin of error acceptable; however, in both Chapter 5 and 6 the plans emphasize that the fuselage sides must be 101.75 inches. Do I have a problem or is my assumption that this is no problem correct? (2) In test fitting F-22 to the forward fuselage sides while still in their jigs with the top of F-22 even with the top of the upper longerons as indicated, none of the lower longeron is exposed; when I place F-22 such that a quarter-inch cross-section of the lower longeron is exposed, the top of F-22 extends beyond the top of the upper longeron one-half inch. I've measured the forward end of the fuselage sides and they both are 20.1" as specified. I've also checked my F-22 against the template and it also is correct. What gives? Anybody else have this problem. I don't recall seeing either of these problems in the archives; sorry, if they are there and I just missed them. Thanks in advance for any advice. -- Jody Hart New Orleans, LA Cozy Mark IV plans no. 648 Chapter 5, see latest progress at: home.gs.verio.net/~jodyhart/home.html N359JH (reserved) From: cdenk@ix.netcom.com Date: Mon, 9 Nov 1998 08:13:47 -0600 (CST) Subject: Re: COZY: Two Fuselage Assembly Questions Jody writes I think this is within dimensional tolerances for this dimension. If I take the 1/8" and divide it by 100" (Very Roughly center of lift of canard to wing) = 0.1% well within reason. But, this is why we flight test to verify performance, if this and several other variables are in the same direction performance wise, then there is noticeable change. Date: Mon, 09 Nov 1998 21:54:46 -0600 From: "Joseph H. Hart IV" Subject: Re: COZY: Two Fuselage Assembly Questions As those of you who watch my webpage know, I haven't been able to do much building in the last couple of weeks after having gotten off to a running start. At the risk of sounding a bit "gushing" and of revealing my true frustration with everything BUT building the Cozy right now, I have to say something: YOU PEOPLE ARE FANTASTIC! Just when I get home from another day of ridiculous hours with little appreciation, I check my e-mail and, as I've grown to know will be the case, I have a number of responses to last night's questions from: (1) the designer of the plane, (2) those of you who are long past Chapter 6, and (3) those of you who are close to where I am at in the building process. Thank you to all who are always there to give advice and support. I especially thank Marc. I can't imagine (and wouldn't want to!) building the plane without having the luxury of access to this group. -- Jody Hart New Orleans, LA Cozy Mark IV plans no. 648 Chapter 5, see latest progress at: home.gs.verio.net/~jodyhart/home.html N359JH (reserved) Date: Sun, 15 Nov 1998 11:22:07 -0600 From: "Joseph H. Hart IV" Subject: Re: COZY: Two Fuselage Assembly Questions  

"Marc J. Zeitlin" wrote:

Only one of whom posted their answer to the whole group so that we ALL
could see it - Carl Denk was the only one to respond publicly.  If you
would be so kind as to summarize the answers and post them to the group,
then the answers will end up in the archives and will be available for all
time :-).  Thanks.
Marc:

    The strange thing about your post is that I received a private e-mail that requested any responses that I got.  Without checking the accuracy of my statement, I assumed (you know what they say about those that assume) that all of the response that I received were sent to the group and advised the sender of the private e-mail accordingly along with a spiel about the importance of everything being posted to the group for the benefit of all.  Thus, I extend my apologies to Dana Hill and summarize the responses below.  However, before doing so, EVERYONE needs to be reminded of the importance of posting all responses/experiences to the entire group.  The efficacy of this forum is seriously undermined if response are private.

    Perhaps, those who responded to my questions had some reason for not posting to the group.  With that in mind, I won't identify the responders except for Nat.  The obvious reason for identifying Nat's response (and I apologize to you, Nat, if you didn't want your advice to published to the group) is that, as the designer of the plane, when it comes to questions like those that I posted, Nat's advice trumps all others IMHO.

    From checking my records, I appears that I received a total of five responses which I have copied below after having redacted the senders' names:

_____

(1)    I think you will encounter some difficulty later on.  This is one thing that I made specifically to plans without error.  It might be fixable, almost everything is on this plane.

I believe the bulkhead problem is something that has been discussed.  I was told by a builder to make everything oversized and then sand or file to fit the fuselage profile.  This has worked for me. If you are where I think you are you still have to put the bottom on the fuselage.  This is not a problem.

Keep building

_______

(2)    Nat has in person told me twice about builders with the 101.75 a little
too short and said it does not matter.  Just make sure that everything is
square and it will be fine.

If you put the upper longerons where they are supposed to be and nail
them as instructed all you have to do is spread the bottom a little.  The
jigs for the sides on the table aren't that exact.  Nat told me that the
long EZ sides were built flat and bent to fit so that also isn't an exact
science.  He just has us build them prebent to make assembly easier.

I talked to Nat a long time about this stuff one day and came to the
conclusion that I was trying to build to tolerances that are not in the
plans and don't matter.  If you have already built these things I guess
that it is obvious.  It wasn't obvious to me, I am new to this.  That is
what we pay Nat the big bucks for though.  He was very gracious and
helpful despite all my questions that must have seemed silly to him.  Jeb

_______

(3)    I had exactly the same problem. Fuselage 1/8" too short (actually 1/4"
too short) and the smae problem with the lower logerons not exposed.  I
ignored the top part of f22 sticking out as it will be sawn of later
on.  I believe that the canard will still be at the correct water line.
I have now finished chapt 8 and all looks well.  I think the Cozy has
been designed with room for little discrepancies and small errors.  Just
go ahead and build ... it will work out OK.

________

(4)    Because of how I placed my aft longeron doublers, my fuselage
sides turned out to be 1/8" short.

I never mentioned this in any of my previous posts, but my sides came up
1/8th inch short, too.  It was my measurement error.  All I did was add in
a little extra foam and floxed the firewall in place.  Guess what?  I ended
up sanding most of that away when trying to get the "smooth transition
taper" while carving the fuselage sides in Chapter 7.  The major strength
from the sides to the firewall occur with the wrap-around edge treatments
applied in Chapter 7 and in later chapters.  Personally, I wouldn't worry
about the 1/8" shortcoming.

In test fitting F-22 to the forward fuselage sides while still in
their jigs with the top of F-22 even with the top of the upper longerons
as indicated, none of the lower longeron is exposed;

I thought I had the same problem.  I "cured" this by simply pushing the
sides (lower longeron) out from F22 until I had the required longeron
showing.  Of course, this meant that the exterior side foam was no longer
flush with F22.   No matter, I simply carved the taper in Chapter 7.  You
also sand in a 1-inch x 1/16th" joggle there in Chapter 7 anyway.

________

(5)    Nat's response:

1) Don't worry about 1/8" difference in length.
2) Sounds to me like your fuselage sides aren't quite deep enough at the
front. Suggest you mount F22 in line with the top longerons (so the
canard
won't end up too high) and then remove a little of the bottom corners of
F22 as you round the fuselage and expose the lower longerons.

_______

--
Jody Hart
New Orleans, LA

Cozy Mark IV plans no. 648
Chapter 5, see latest progress at:
home.gs.verio.net/~jodyhart/home.html
N359JH (reserved)
  From ???@??? Fri Dec 04 20:33:52 1998 Return-Path: owner-cozy_builders@betaweb.com Received: from twc2.betaweb.com (majordomo@betaweb.com [206.43.209.18]) by acestes-fe0.ultra.net (8.8.8/ult/n20340/mtc.v2) with ESMTP id TAA03124 for ; Fri, 4 Dec 1998 19:58:18 -0500 (EST) Received: (from majordomo@localhost) by twc2.betaweb.com (8.8.5/8.8.5) id TAA29701 for cozy_builders-list; Fri, 4 Dec 1998 19:45:07 -0500 X-Authentication-Warning: twc2.betaweb.com: majordomo set sender to owner-cozy_builders@betaweb.com using -f Received: from imo26.mx.aol.com (imo26.mx.aol.com [198.81.17.70]) by twc2.betaweb.com (8.8.5/8.8.5) with ESMTP id TAA29696 for ; Fri, 4 Dec 1998 19:45:02 -0500 From: Chm12345@aol.com Received: from Chm12345@aol.com by imo26.mx.aol.com (IMOv18.1) id 9JEJa25365 for ; Fri, 4 Dec 1998 19:40:29 +1900 (EST) Message-ID: <95511d77.366880fd@aol.com> Date: Fri, 4 Dec 1998 19:40:29 EST To: cozy_builders@betaweb.com Mime-Version: 1.0 Subject: COZY: VA fuel sight gages Content-type: text/plain; charset=US-ASCII Content-transfer-encoding: 7bit X-Mailer: AOL 4.0 for Windows 95 sub 224 Sender: owner-cozy_builders@betaweb.com Precedence: bulk Reply-To: Chm12345@aol.com X-UIDL: ef6fbec025cab2f0332f6b214f184332 I know this is an old subject but I still have a question: I'm glassing the fuselage sides tomorrow and I'm going to install the VA fuel sight gages. The plans and the archives talk about a flat recess 7"x2". Is .2" deep the correct depth?. I also remember reading that the recess should be a little longer so that his thing fits better. Is that necessary or is 7"x2" flat OK?. If it needs to be longer, by how much?. Thanks for the assistance. BTW, I have created a small web page where I'm keeping a photographic documentation of my cozy's progress. The address is: http://hometown.aol.com/chm12345/ccweb.htm Chris Martin From: "L. Wayne Hicks" Subject: COZY: RE: Ch 5 holding longerons to foam while gluing Date: Fri, 11 Dec 1998 13:38:55 -0500 -----Original Message----- From: Hill-EQE, Dana [SMTP:Dana.Hill@state.ma.us] Sent: Friday, December 11, 1998 10:28 AM To: hicks@spacetec-inc.com Subject: re: Ch 5 holding longerons to foam while gluing Hi Wayne, Things are going pretty well here. Hope alls well with you. One multi part question when you have time please. You had mentioned in one of your emails in the archives that you had used dry wall screws to hold the foam spacers and lower longeron (and not the upper longeron?) while microing/floxing these to the sides. Did you predrill the longeron first? At a minimal depth and diameter, right? Why was it necessary to hold the foam spacers down, don't you micro this to the blue foam on the flat prior to installing all of the foam into the jigs? Thanx for any help Wayne. Dana Hill CZ #676, Ch 5 [L. Wayne Hicks] Things are going well for #678. I will lay up the inside tabs for the landing gear tonight, then install into the fuselage this weekend. I don't have enough money for wheels and brakes yet, but maybe next month. As for your questions: 1. (Dana's question-->) You had mentioned in one of your emails in the archives that you had used dry wall screws to hold the foam spacers and lower longeron (and not the upper longeron?) while microing/floxing these to the sides. (My answer-->) Yes, I used 3/8th-inch screws over most of the foam every 12 inches or so in a checkerboard pattern. I used 2-inch screws along the bottom longeron to: (a) first hold the PVC foam to the jig; (b) next hold the foam spacers to the PVC foam while the micro cured; and finally (c) to hold the lower longeron is place while the flox cured. 2. (Dana's question-->) Did you predrill the longeron first? At a minimal depth and diameter, right? (My answer-->) Yes, I predrilled the lower longeron, but only deep enough to get enough screw threads to hold the longeron in place. In some places, especially in the curvy sections, I had to drill a deeper hole so as to apply enough hold-down force to get the lower longeron to screw down and sit properly onto the spacer foam. The way I did this was to dry fit everything before microing or floxing. With one hand, I held everything is position (PVC, spacer, lower longeron). With the other hand, I drilled from the bottom through the masonite, PVC, spacer, and then into the longeron. Then I put the screw in. I repeated this about every 6 inches. After I was happy, I disassembled everything. One of the reasons I went with this approach was because I was having a difficult time getting my clamps to stay on the triangular face of the lower longerons. 3. (Dana's question-->) Why not on the upper longeron? (My answer-->) Well, I actually did this during the dry fit. But there's something to be said for thinking things through when you're about to do something different than what's in the plans. I did not take into account that after my jigs were placed side by side and screwed down to the table, there was no way to get underneath to screw in the screw to hold the upper longerons in place. So with wet flox everywhere, I made an emergency run to the hardware store, purchased 20 one-and-a-half -inch clamps and rushed home. Well, that was error #2 as the clamps were too small. So I ran back to the hardware store only to realize that those were the only size clamps they had. So I got my money back, rushed to another store, bought the right sized clamps, and finished the job before the flox set up. There's something to be said for being thoroughly prepared with the right tools in hand. Ugggg. 4. (Dana's question-->) Why was it necessary to hold the foam spacers down, don't you micro this to the blue foam on the flat prior to installing all of the foam into the jigs? (My answer-->) The spacer foam won't stay down onto the PVC foam without clamps or weights, especially in the curvy sections. So, I used the 2-inch screws to hold down the spacer foam. From underneath the masonite, I screwed in the 2-inch screws (by hand) until the tip of the screws barely broke the top surface of the PVC foam. I micro'd the spacers and PVC foam, put the spacers in place, then pressing firmly with one hand, I reached underneath with the other hand and screwed the screw in all the way. If the screws broke through the top surface of the white spacer foam, I backed them off just a bit. During micro and flox curing, I rotated each screw every hour or so to make sure none of the screws got permanently bonded. You know, I didn't think of micro'ing the foam spacers to the PVC foam prior to installing the whole thing onto the jigs. I guess the success of that approach would depend on how flexible the clark foam is (it's flexible), and more importantly, how flexible is the micro after it's cured. I could foresee that the micro may crack when bending the foam onto the masonite. Maybe, maybe not. There's another reason--> It's important for the aft end piece of Clark foam to be located at the correct FS location. I'm talking about that big, honker of a piece that's all the way at the aft end, spans from upper to lower longeron, and has the electrical duct cut into it. All measurements to determine location are measured straight-line distance from the forward end. They are not measured as a curve following along the longeron. (If you measure along the longeron, the honker piece will be located in the wrong place by about 3/4ths of an inch.) So I can see that it might be a little hard to anticipate the correct placement of the spacer pieces, especially that honker piece (new name, Nat?), without first determining their positions with the PVC foam in place on the fuselage side jigs first. I interpreted the plans to have us first mount the PVC foam onto the jigs, then mark, cut, micro the spacers onto the PVC foam. Good Luck, Wayne Hicks Cozy IV #678 Chapter 9