Date: Tue, 07 Jan 97 16:59:33 EST From: "Larry Schuler" Subject: COZY: Ch-6; Vacc Bagging Been quite a while since I have had time to post to the group. I think my last note (maybe back in November) indicated I was working on the forms for the fuselage bottom to do vacc bag. The bottom is now on the fuselage. Here is how I did it for whatever it's worth to anyone: I used the dimensions called out for the bottom edge of the fuselage sides, did a little straight-line subtraction to convert to some 2" X 6" lumber and ran the numbers through a QBasic curve-fitting program. I have been using the curve-fitting routine for all the curves on longeron forms, sides, and so-on; it sure works well and smooths out all the straight lines between the few coordinates called out in the plans. The program allows me to plot the curves on the screen in various scales which is really helpfull for seeing if I mis-entered a point (once in a while I miss a decimal or something stupid, so it shows like a sore thumb). I can add as many "x" coordinates as I care to lay out (every 0.00001" if I want). In this case I decided that every 1/2" over the length of the forms was sufficient. From the curve-fitting program, I made three forms of 1" X 6" in a similar manner to those used for the top longerons and sides. These I set aside for the time being because I still needed the work table to lay out the foam. After all said and done, I think that four 1 x 6 forms would have been better, but three was "ok"; just some very slight masonite sag between the forms (didn't measure it, but I'd say not much more than a tenth of an inch in a few spots). Next, I 5-Min epoxyd the PVC pieces for the bottom and cut it out per plans. Then laid the PVC on a sheet of masonite and traced the shape onto the masonite. Then set up the forms on my work table; tapped (double-sided scotch tape) and caulked the vacc bag plastic to the bottom side of the masonite (letting excess plastic hang over the sides of the table wile working on and glassing the foam) and then sheetrock screwed the masonite to the forms. I put dabs of caulk between the masonite and plastic where I (pre-marked both sides) planned to use the sheetrock screws. I use a cheap construction caulk for sealing the vacc bag (less than $2.00 per tube at lumber yard); works real well and one heck of a lot cheaper than anything else available. In the case just described, the caulk seals the plastic where the screws penetrate. Don't want to run a bead the entire length of the forms as it will deform the masonite (unless you use a gazillion screws to squish it all down). The plastic I use for vacc bag is some 4-mil black poly plastic left over from the construction of my shop (used as vapor barrier under the concrete and on the walls). It came in a 20' X 100' roll and seems to be tough enough so it doesn't puncture easily. At '95 Oshkosh, Bailets had suggested the use of garbage bag plastic; the thicker, yard clean-up type. I'll try those for smaller projects when this stuff runs out; I still have about 20' X 30' of it left. I cut out the landing brake per plans except that I will follow Phillip Johnson's advice on extending the hinge the full width of the brake to make it stronger. I coverd the chamferd edge of the fuselage bottom around the brake opening with box tape (I use the very thin stuff) and extended this the width of the tape on the exterior side of the bottom. Next I taped the landing brake chamfered edge and continued the tape over the entire inside surface of the brake. I inserted the brake in position and taped it in place on the underside of the fuselage bottom. I don't know yet if this is all good because I have't gone to chapter 7 yet and the brake is still taped in place (at least I "hope" none of the epoxy or micro seeped in anywhere). I used box tape along the edges (half on top and half on bottom) of the masonite and an extra strip along the top and bottom of the front edge where the BID needed to extend down the edge of the foam (mate to F22). I 5-min epoxied the PVC to the masonite (same as fuselage sides were done); then laid out and microed the foam doublers in place. The doublers took a week to make (could have left some gaps for micro to take up, but guess I'm picky). Here's a learned the hard way note: When I "popped" the bottom off the masonite later, I made a big mistake and forced it too quickly ripping out a few chumks of foam in the process {these have been repaired}. Take heed folks: If I had gone a lot slower, the masonite skin will give before the foam and leave some small areas of masonite stuck to the foam that can easily be smoothed out with a flush-cutting bit in a router or dremel (I used a Dremel). Se La Vi. I ran out of Lastafoam (some earlier boo-boo's), so I ended up using some 3/4" PVC left over from the seatback [I had ordered 2 sheets of this foam rather than the one called out due to wider fuselage] for the area over the landing break. I think this is better than the lastafoam for this area anyway; PVC is a lot tougher than Lastafoam or urethane. Anyway, it looked (see chapter 6 pictures in the plans) like NAT used two pieces of 3/8" PVC microed together in this area on his. I used a single 3/4" thick piece instead. I then prepared to glass per plans. Plans call for an additional BID layer "ahead of the rear seat in any orientation" to help take stress of people climbing in and out. I decided to do this full length for couple of reasons: 1) plans called for foot-traffic area of the floor anyway and 2) I am building fuselage 6" wider 3) weight saved via vacc bag allows for some weight additions here and there. Soon as the epoxy was on and glass wet out, I laid on the peel ply cut in sections to cover the space between bulkheads etc, snipping the corners for the taper of the doublers and using small pieces to fill the gaps. Next, I laid down the release ply allowing lots of excess {many "pinches" of plactic} for the doubler transitions; laid on the bleeder; and, closed the bag (using caulk of course) and started the pump.... only had two small leaks; one along the caulk seam. The caulk allows an easy fix; simply run a finger over the plastic where the bead of caulk is and squish it into the gap that is leaking. The other leak was a puncture caused by my belt buckle while working on the glassing; all I needed to do was cut a small square of plastic and run a very thin bead of caulk in a circle a bit bigger than the size of the hole (actually, I think I smeard it on with my finger); slapped the "patch" on and bingo, perfect seal. Can't get much simpler than that. I Let it cure for about a day and a half under vacc. I live in Wisconsin and although the shop is heated, it gets expensive to keep it at 70 Deg or so when it's unnecessary [or i'm not in it]. After a layup at normal working temps (2427 has been fairly nice at 65 or 70 Deg, but wet-out sucks at 60 or less), I have been allowing the part(s) to cure for up to two or even three days at 55 to 60 Deg. I still get a good cure, it just takes longer before I feel comfortable enough to pull off the peel ply; I have done it on a small part after 24-hours at about 55 Deg and the Epoxy still felt "soft" {called 'B-stage'}; waited another 24 hours on the same part and it was same as if it had cured 24 hours at 70 Deg..... What's right? Beats me; all I know for sure is that ALL of my airplane is going to get a good post-cure in a home made oven so that ALL parts, pieces and combinations of parts and pieces end up with the same Tg properties to eliminate at least that one "potential" source of weak spots. Wings are going to be a bear to support; but I like a good challenge. Back to current.... I was really sweating the fit of the bottom on the fuselage due to a number of reasons: a) not being able to trial fit the bottom after the doublers were in place; b) my adaptation of the bottom curvature from the dimentions of the sides {from the plans, not from the actual sides}; and, c) my markings on the bottom for the doublers, heat duct, etc. All good reasons to sweat. Shouldn't have worried at all as it turned out. After using a straight edge along the fuselage bottom (side-to-side) at bulkheads, seatback, and along the heat duct/seat brace to "adjust" any slight peaks and valleys; the fit was about as perfect as mating a nut and bolt. The very slight variations which I did have {mostly due to the minor sag of the masonite between the forms} were easily taken up with the flox and weights used to mate the bottom to the sides. Well... the bottom is on the fuselage finally and I am currently BID taping the joints with the fuselage upright. I had decided to let the flox cure before taping; almost wish I hadn't because it took me a week just to sand the joints in prep for tapes. The back side of the seatback was a real treat! Decission was based on my use of 2427 and it's "reported" problem with adhesion after it starts to cure. I havn't experienced the problem, but didn't want to take a chance; this isn't a good place to be testing it. I had visions of flying along at 10,000 feet and falling out the bottom; figured a little sanding is an excelent price for peacefull sleep. Hope this is usefull to someone. Larry Schuler MKIV-#500 (At the end of Ch-6; looking in the scrap box for BID sections long enough for taping the fuselage bottom since my roll of BID ran out [ok, I used more than called for on the inside bottom and only had ordered through chapter 7]). Where's the sad violin when ya need one... Date: Sun, 27 Apr 1997 09:52:20 -0400 (EDT) From: SWrightFLY@aol.com Subject: COZY: High quality Fuel valve (on/off)---filter---As Used in my Stagger-EZ Suggest anyone looking for the above should FAX Fuel injector engineering company in California for a catalogue 714-582-3795, in which you will find a shutoff valve part#F521B6....$50.00 and a fuel filter machined from stainless steel and weighs 7 ounces and will stop anything 25 microns or larger---perfect for fuel injectors part#f1200-8 (fine mesh) $93.00 These items are for those of us who wish to have one central fuel sump ( as designed by Vance Adkison) which makes fuel management easier and more goof-proof for us guys who tend to ''goof-up" more occasionally. Date: Sat, 31 May 1997 23:56:09 -0400 (EDT) From: AlWick@aol.com Subject: COZY: Floor boards Recommend you add the 5" high x 17" rear seat support to the floor boards before letting yourself step into tub. See book 2, installing rear seat instructions. Basically the back seat floor boards are not well supported. If you step back there, the glass seems prone to breaking loose from the foam. Once that occurs, it doesn't matter how many layers of glass you add, it still feels spongy and creaks. This condition may vary tub to tub, but why risk it? Happy building. -al 62% complete. Date: Mon, 09 Jun 1997 15:27:59 -0500 From: tpierce@ghg.net (Terence J. Pierce) Subject: COZY: chapter 6, fuel selector I thought at one time there was a thread about people using a different fuel selector than what is called out in the plans. I could only find one entry in the archives about a different valve for people using a single sump. Is anyone else using a different fuel selector? If so which one? Why? Where did you get it? And how much was it? Thanks, -- Terry Pierce e-mail: tpierce@ghgcorp.com Cozy Mark IV #600 Date: Mon, 9 Jun 1997 19:49:10 -0400 (EDT) From: SWrightFLY@aol.com Subject: Re: COZY: chapter 6, fuel selector Several of us that use a central sump (by far the safest way to go- my opinion) are using a fuel shut off valve (F521B-6) from Fuel injector Engineering Co. Laguna Niguel CA phone 714-582-1170. Cost $50.00. Steve Wright Wright Aircraft Works LLC From: "Rob Cherney" Organization: Ellicott City, Maryland Date: Mon, 9 Jun 1997 23:04:21 -0400 Subject: Re: COZY: chapter 6, fuel selector Terry: > Is anyone else using a different fuel selector? If so which one? > Why? Where did you get it? And how much was it? At Sun-N-Fun there was a British fellow who was making some very high quality fuel selectors. I would seriously look at these. Although they are more expensive than what the plans call for, I would not hesitate to spend the extra money for this critical item. The most interesting thing about these selectors is that they have a mechanical interlock button that must be pulled to enable the selector valve to turn to the OFF position. It takes an act of volition to screw up. And now the details: They are made by Andair, Ltd. They are sold by Spruce, Wicks, and Chief Aircraft. Details can be found on their web site: http://www.andair.co.uk or they can be reached by e-mail at . They make about 5 different versions of the valve and they also make a real nice gascolator. Rob- +--------------------------------------------------------+ |Robert Cherney Home Phone: (410)465-5598 | |Ellicott City, Maryland e-mail: cherney@clark.net | +--------------------------------------------------------+ Date: Sun, 20 Jul 1997 08:25:19 -0500 From: tpierce@ghg.net (Terence J. Pierce) Subject: COZY: chap. 6, taping bulkheads to sides I am on chapter 6 and I am ready to tape the bulkheads to the sides. The plans call for 2 plys of BID tape on the joints. What I would like to do is use some of the S2 glass 45 degree tape I got from AS&S (page 18 in their catalog). They claim 100% strength increase over E-glass. This tape is nice because it has a lite random pattern of glass attached to the top and bottom, that keeps the main fibers in their 45 degree orientation (meaning, no streching and compressing like regular BID). Anyhow, my main question is do you see a problem with using this stuff? And with the increase in strength can I get by with 1 ply ( this stuff isn't cheap)? Thanks, Terry Pierce mailto:tpierce@ghg.net Cozy Mark IV #600 From: SWrightFLY@aol.com Date: Sun, 20 Jul 1997 20:40:50 -0400 (EDT) Subject: Re: COZY: chap. 6, taping bulkheads to sides In a message dated 7/20/97 1:32:36 PM, tpierce@ghg.net (Terence J. Pierce) wrote: <> I suggest you ask yourself....What improvement are you attempting to make with this deviation from the plans??? If you can't answer that question with total confidence and engineering data then do not deviate. I'm on my second EZ and have made major changes to achieve what I feel are specific design and performance improvements (but only in theory until it flies) and I strongly recommend you build your first one strictly by the "book"---don't change anything on your first airplane. Steve Wright STAGER-EZ From: "Steve Campbell" Subject: COZY: Chapter 6 Date: Fri, 22 Aug 1997 10:29:29 If memory serves me, this is one of the 3 times that I have called Nat over the last 30 months. The bulkheads get taped (I believe that it was two layers of BID) just like all the other joints in this section, even though it is not explicitly called out. Steve Campbell Cozy/Aerocanard; Finished through 12, working on 13 and 20. On Fri, 22 Aug 1997 10:09:24 -0500, tpierce@ghg.net wrote... >I am istalling my landing gear bulkheads in chapter 6. I don't see >anything in the plans about taping the joints (tub sides to the >bulkhead). Do these need to be taped? >-- >Terry Pierce mailto:tpierce@ghg.net >Cozy Mark IV #600 > > Date: Fri, 22 Aug 1997 10:09:24 -0500 From: tpierce@ghg.net (Terence J. Pierce) Subject: COZY: chapter 6, landing gear bulkheads I am istalling my landing gear bulkheads in chapter 6. I don't see anything in the plans about taping the joints (tub sides to the bulkhead). Do these need to be taped? Do they get taped in another chapter? If I do need to tape them in chapter 6, do I wait until I add the 8 plys of UNI on one side and 3 ply of UNI on the other? Thanks, -- Terry Pierce mailto:tpierce@ghg.net Cozy Mark IV #600 Date: Fri, 22 Aug 1997 11:48:15 -0400 From: bil kleb Organization: NASA Langley Research Center Subject: Re: COZY: chapter 6, landing gear bulkheads Terence J. Pierce wrote: > > I am istalling my landing gear bulkheads in chapter 6. I don't see > anything in the plans about taping the joints (tub sides to the > bulkhead). Do these need to be taped? yes, according to the builder hints for newletter #36, jan 92 or newsletter #50 jul 95. see: http://www.ultranet.com/~marcz/cozy_mkIV/newsletters/news_toc.html however, all the joints are effectively "taped" by the sequence of lay-ups in the beginning of chapter 9 > If I do need to tape them in chapter 6, do I wait until I add the 8 plys > of UNI on one side and 3 ply of UNI on the other? i think i waited until after/during the 8 & 3 ply lay-ups mentioned at the end of chapter 6, step 1 to tape the joints. BTW: the 96 archives have a sizable discussion of this and similarly related landing gear bulkhead issues for chapter 6. -- bil Date: Thu, 28 Aug 1997 09:13:22 -0500 From: tpierce@ghg.net (Terence J. Pierce) Subject: COZY: Fuel lines , throttle & mixture I am getting ready to build the center keel in chapter 6 and wasn't sure where the fuel lines, and the throttle and mixture control lines were ran. Do they run down the inside of the heat duct or are they above the heat duct? -- Terry Pierce mailto:tpierce@ghg.net Cozy Mark IV #600 Date: Thu, 28 Aug 1997 11:39:29 -0400 From: bil kleb Organization: NASA Langley Research Center Subject: Re: COZY: Fuel lines , throttle & mixture Terence J. Pierce wrote: > > Do they run down the inside of the heat duct or are they above the > heat duct? above. for example, see drawing of landing light/throttle quadrant at the end of chapter 17. also see the text describing figure 21 in chapter 6. you are to make a notch in the top of the forward heat duct to clear the fuel tube as it comes out of value (shown in figure 19, chapter 21). -- bil Date: Sun, 07 Sep 1997 23:54:51 -0500 From: tpierce@ghg.net (Terence J. Pierce) Subject: COZY: fuel valve The Andair fuel valve came highly recommended from this group. Can someone who has one installed tell me where and how they installed theirs? I bought the FS20X4 ( left, right, both and off). Thanks, Terry Pierce Cozy Mark IV #600 Date: Fri, 26 Sep 1997 00:13:24 -0500 From: tpierce@ghg.net (Terence J. Pierce) Subject: COZY: Chapter 6, fuel valve mounting bracket Ok, I just broke my second piece of 1/16 inch 2024-T3 aluminum trying to bend it 90 degrees to make the fuel valve mounting bracket. What the heck am I doing wrong? I have waited for a week now for the new piece to come in, then crack. When I get it to about 85 degrees, crack. Are they sending the wrong type of aluminum? I tried experimenting with one of the cracked pieces. I heated it up with a propane torch before I tried bending it. It didn't brake this time, but I see some cracks in it. Ticked off in Texas, and about to use galvenized steel, Terry Pierce mailto:tpierce@ghg.net Cozy Mark IV #600 Date: Fri, 26 Sep 1997 08:27:25 +0200 From: Rego Burger Subject: COZY: Chapter 6, fuel valve mounting bracket -Reply Hi Terry, I'm no expert par for the fact I made three before I got it right. 1.) Bend inline with the "grain" of the metal this is parralel with the markings on the sheet. 2.) DON'T try making a sharp corner! Gently tap around a curved former. My radius was about 1/4" 3.) Don't do it ice-cold I warmed the metal with a hairdryer till I could just hold it without feeling that I was burning. Good luck on the next piece. Rego From: "mel" Subject: Re: COZY: Chapter 6, fuel valve mounting bracket Date: Fri, 26 Sep 1997 08:09:01 -0400 probably correct metal. but you didnt bend it across the grain (YES THE GRAIN) look at it carefully youll see lines going in one direction this is the grain. i had the same problem and some metal plane friends set me straight. norm & monda cozy IV #202 ---------- > From: Terence J. Pierce > To: cozy_builders@hpwarhw.an.hp.com > Subject: COZY: Chapter 6, fuel valve mounting bracket > Date: Friday, September 26, 1997 1:13 AM > > Ok, I just broke my second piece of 1/16 inch 2024-T3 aluminum trying to > bend it 90 degrees to make the fuel valve mounting bracket. > > What the heck am I doing wrong? > > I have waited for a week now for the new piece to come in, then crack. > When I get it to about 85 degrees, crack. Are they sending the wrong > type of aluminum? I tried experimenting with one of the cracked pieces. > I heated it up with a propane torch before I tried bending it. It > didn't brake this time, but I see some cracks in it. > > Ticked off in Texas, and about to use galvenized steel, > > Terry Pierce mailto:tpierce@ghg.net > Cozy Mark IV #600 From: ponciroli@postoffice.worldnet.att.net Date: Fri, 26 Sep 1997 08:39:50 -0500 Subject: Re: COZY: Chapter 6, fuel valve mounting bracket -Reply comment In a response to Terry, Rego Burger advised: >1.) Bend inline with the "grain" of the metal this is parralel with the markings on the sheet. I used to be an aviation metalsmith in another life and if I recall correctly and I believe that I do, aluminum must always be bent pependicular to the grain not parallel. Bending parralel to the grain weakens the peice. Don Ponciroli From: Marc J. Zeitlin Subject: COZY: Chapter 6, fuel valve mounting bracket (fwd) Date: Fri, 26 Sep 97 9:48:04 EDT Terry; >Ok, I just broke my second piece of 1/16 inch 2024-T3 aluminum trying to >bend it 90 degrees to make the fuel valve mounting bracket. > >What the heck am I doing wrong? Not a thing. As others have said, bend across the grain with a large radius if you continue to use the 2024-T3. The real problem here is that Nat (Burt?) has spec'ed the wrong type of aluminum - a 2024-T3 is not meant for sharp sheet metal bending. A 5052 type would have been more than adequate from a strength standpoint and would allow a right angle bend first time, every time, no cracks. Don't know if Wicks or AS carries it, though. We had some lying around our shop here at work, so I took a small scrap after breaking two pieces of the 2024-T3. -- Marc J. Zeitlin Email: marcz@an.hp.com Date: Fri, 26 Sep 1997 09:18:33 -0500 From: Bulent Subject: Re: COZY: Chapter 6, fuel valve mounting bracket Hi Terry, I had the same problem until another builder enlightened me that the aluminum sheets have a grain, and you must bend 90 degree to the grain of the sheet. It is visible to the naked eye. Also you must bend over a round edge. Sharp edge will crack it. Bulent by r2.boston.juno.com (8.8.6.Beta0/8.8.6.Beta0/2.0.kim) with ESMTP id OAAAA15878 for ; Fri, 26 Sep 1997 14:50:57 -0400 (EDT) by x14.boston.juno.com (queuemail) id OWD06570; Fri, 26 Sep 1997 14:47:35 EDT Date: Fri, 26 Sep 1997 14:46:03 -0400 Subject: COZY: Fuel valve bracket From: gmellen@juno.com (George J Mellen Jr.) Terry , I remember breaking a few of these also. Use a scrap piece of 2x4 lumber to form it around, the radius works well for bending this stuff to the 90 deg. you need. George Mellen gmellen@juno.com From: AlWick@aol.com Date: Fri, 26 Sep 1997 16:37:57 -0400 (EDT) Subject: Re: COZY: Chapter 6, fuel valve mounting bracket In a message dated 97-09-26 01:19:51 EDT, you write: << Ok, I just broke my second piece of 1/16 inch 2024-T3 aluminum trying to bend it 90 degrees to make the fuel valve mounting bracket. What the heck am I doing wrong? >> It's a poor design for the type of material specified. Even a production shop would have parts which crack. Alum has a grain, and cracks along the grain. So all bends should be at 90 degrees to grain. You can see grain by looking at surface. Use a much larger radius than specified. Bigger, the better. Notch the corners prior to bending to relieve the high stress. All cracks start at the corner's edge you are creating as you bend. After bending, go ahead and relieve the corners further by chamfering the edge. Reduces chance of crack developing. Go ahead and use some other material, nothing sacred about alum in this application. Good luck! -al (used to work at sheet metal shop) Date: Fri, 26 Sep 1997 16:27:57 -0700 From: Rego and Noleen Burger Organization: R.N.B. Enterprises Subject: Re: COZY: Chapter 6, fuel valve mounting bracket -Reply I wrote:> 1.) Bend inline with the "grain" of the metal this is parralel with the markings on the sheet.<<<< Please update to read: Bend across the grain which is parallel with the markings on the sheet. I'm sending a sketch direct to the guy who asked, its worth a thousand words..:-)..bad english on my part. Thanks Don! -- Rego Burger CZ4#139 RSA, http://home.intekom.com/glen/rnb.htm From: RGCardinal@aol.com Date: Fri, 26 Sep 1997 22:22:12 -0400 (EDT) Subject: COZY: Fuel valve bracket Noted all the comments re: cracking of the metal. I offer this bit of info for your consideration. After first making and cracking a bracket from metal, I made one from glass. Used a piece of 2" foam cut to the inside demensions, slightly rounded the corners, covered with saran wrap and placed a six layer layup over it. After curing, I cut it to template shape with a dremel and file. Drilled some holes and attached some nutplates. Turned out fine.. If glass holds the wings on, I think it's strong enough for a hand operated valve. Thoughts are appreciated, hope this helps someone Robert Kittler; sn 589 by m5.boston.juno.com (queuemail) id T}T22248; Sun, 28 Sep 1997 19:06:44 EDT Subject: Re: COZY: Chapter 6, fuel valve mounting bracket From: mbeduhn@juno.com (Mark W Beduhn) Date: Sun, 28 Sep 1997 19:06:44 EDT On Fri, 26 Sep 1997 00:13:24 -0500 tpierce@ghg.net (Terence J. Pierce) writes: >Ok, I just broke my second piece of 1/16 inch 2024-T3 aluminum trying >to >bend it 90 degrees to make the fuel valve mounting bracket. > >What the heck am I doing wrong? > >I have waited for a week now for the new piece to come in, then crack. >When I get it to about 85 degrees, crack. Are they sending the wrong >type of aluminum? I tried experimenting with one of the cracked >pieces. >I heated it up with a propane torch before I tried bending it. It >didn't brake this time, but I see some cracks in it. > >Ticked off in Texas, and about to use galvenized steel, > >Terry Pierce mailto:tpierce@ghg.net >Cozy Mark IV #600 > My first bracket was a disaster (for the same reason). I used some 6061-T6 laying around the shop and it worked fine. You just can't bend 2024 that much. Actually, if I hadn't had the the 6061 laying around I would have used galvenized steel too...why not it's a small part and wouldn't weigh much. Mark Beduhn Cozy IV N494CZ Date: Mon, 20 Oct 1997 08:54:39 -0500 From: tpierce@ghg.net (Terence J. Pierce) Subject: COZY: chapter 6, tub bottom I am about ready to glass the bottom of the tub and I had so questions. #1 What is the best way to get the BID to lay down over the contour of the 3/4 inch foam? Any special tricks? #2 The plans say to put a 3rd ply of BID in front of the back seat where people step to get in the back. What size is that? Where does the back seat start? #3 The plans say that before the lay up is fully cured to flox it to the tub and then crawl up underneath and tape all the joints to the sides and bulkheads. Did anyone really do this? I am going to just peel ply the bottom. After cure sand and then flox to tub. After that is cured flip the whole tub over and then tape the joints. The last thing I want to do is spend hours on my knees crawling in and out from underneath the tub to tape joints upside down. -- Terry Pierce mailto:tpierce@ghg.net Cozy Mark IV #600 From: Epplin John A Subject: RE: COZY: chapter 6, tub bottom Date: Mon, 20 Oct 1997 10:03:30 -0500 > -----Original Message----- > From: tpierce@ghg.net [SMTP:tpierce@ghg.net] > Sent: Monday, October 20, 1997 8:55 AM > To: cozy_builders@hpwarhw.an.hp.com > Subject: COZY: chapter 6, tub bottom > > I am about ready to glass the bottom of the tub and I had so > questions. > > #1 What is the best way to get the BID to lay down over the contour of > the 3/4 inch foam? Any special tricks? > [Epplin John A] That will be no problem, BID will conform to the contour easily. Just radius the edges, sand outside corners and fill inside corners with micro. > #2 The plans say to put a 3rd ply of BID in front of the back seat > where > people step to get in the back. What size is that? Where does the > back > seat start? > [Epplin John A] I assumed from just forward of the forward gear bulkhead to some point about 8 in aft of the lower front seat back. I interpreted this to be the left side only, from center to the left edge of the bottom. > #3 The plans say that before the lay up is fully cured to flox it to > the > tub and then crawl up underneath and tape all the joints to the sides > and bulkheads. Did anyone really do this? [Epplin John A] Yes. I think this is the only way to get a really good fit. If you wait till the bottom cures you will lose a lot of flexibility. I took a in between approach, I put the bottom in place while it was in the gel state and floxed it well. I had mounted the tub on four 2x4 posts screwed to my table about 12 in high so I could slide under the tub easily. Level the posts and make sure the side panels and bulkheads are perfectly square. I drilled 1/8 holes in each end of the longerons and used pins cut from welding rod fitted into the top of the posts to hold everything square. When I was satisfied I had the bottom in place and the flox joint was perfect, I peel plyed the joint area, about 2 inches each side of the joint. The bottom was peel plyed in the areas that were not involved in the bonding at this time while it was still wet. After cure, turn the hole assembly on its side, remove the peel ply and install the tapes. You will need help in doing this, two good helpers would be a good idea. We did it after work in one evening, wife is a handy helper and I have a friend that is a retired A&P that also helped. I got to bed before midnight. > I am going to just peel ply the bottom. After cure sand and then flox > to tub. After that is cured flip the whole tub over and then tape the > joints. The last thing I want to do is spend hours on my knees > crawling > in and out from underneath the tub to tape joints upside down. > > -- > Terry Pierce mailto:tpierce@ghg.net > Cozy Mark IV #600 [Epplin John A] This really isn't dificult to do. Good luck and have fun John epplin Mk4 #467 From: wkasty@ix.netcom.com Date: Mon, 20 Oct 1997 10:32:30 -0500 (CDT) Subject: Re: COZY: chapter 6, tub bottom On 10/20/97 08:54:39 you wrote: > >I am about ready to glass the bottom of the tub and I had so questions. > >#1 What is the best way to get the BID to lay down over the contour of >the 3/4 inch foam? Any special tricks? Two people working plus another one mixing is the biggest trick, otherwise, just don't stop stippling down the cloth in the corners. After it is somewhat setup, don't give up yet. Take a piece of wax paper and with bare hands slide your fingers back and forth, this is over the peel ply so the wax won't affect anything. You want no air pockets. > >#2 The plans say to put a 3rd ply of BID in front of the back seat where >people step to get in the back. What size is that? Where does the back >seat start? I forget the exact dimension of the back seat bottom, look it up in one the later chapters. > >#3 The plans say that before the lay up is fully cured to flox it to the >tub and then crawl up underneath and tape all the joints to the sides >and bulkheads. Did anyone really do this? I did flox the bottom on during this almost cured state,but again you can use some help on this work. I did the bid taping the next day or several days.> >I am going to just peel ply the bottom. After cure sand and then flox >to tub. After that is cured flip the whole tub over and then tape the >joints. The last thing I want to do is spend hours on my knees crawling >in and out from underneath the tub to tape joints upside down. > Good luck with the layup, it makes the tub much more solid. >Terry Pierce mailto:tpierce@ghg.net >Cozy Mark IV #600 > > Bill Kastenholz wkasty@ix.netcom.com From: "norm & monda" Subject: Re: COZY: chapter 6, tub bottom Date: Mon, 20 Oct 1997 11:49:16 -0400 regretably i had to wait for full cure, boy what a b___h the conture was all wrong it required 2x4's ropes bungi cords and a tremdous amount of pressure to get it to all line up, but it did work out ok. norm & monda cozy IV #202 ps. these arent caps as they look its the new look of internet explorer 4.0 witch im not to sure about yet Date: Wed, 22 Oct 1997 17:44:40 -0500 (CDT) From: cdenk@ix.netcom.com Subject: COZY: Fuselage ibottom installation The other day there was some discussion of installing the fuselage bottom, and taping the bulkheads and sides at a later date. I do not recommend this: After the bottom is set in place, the flox will (it had better) squeeze out. Its necessary to clean this off flush before it cures. In the process of cleaning you will smear flox (epoxy) onto the adjacent surfaces. This will then require sanding to prepare for the tape. If your going to try to peal ply, your working with skew surfaces, peal ply will not lie flat. Its not that difficult to tape if you make the tapes as follows: 1: masking tape a layer of (news) paper to your your bench 2: With a broad felt tip pen, mark 45 degree, 2" wide lines as wide a the BID, and enough lineal length plus to do the job. 3: tape a layer of wax paper on top. 4: Layup the BID plies. 5: Add another layer of wax paper on top to stabilize the BID. 6: CUt with a razor blade knife on the lines. 7: Remove to wax paper. 8: Use bottom waxpaper as carrier to place tape, then peal off, pat into place with paint brush, and pealply with 1" tape both edges.