---------------------------------------------------------- RV7-List Digest Archive --- Total Messages Posted Thu 08/07/08: 4 ---------------------------------------------------------- Today's Message Index: ---------------------- 1. 12:07 PM - -7 tipup rear window fitting problem (Charlie England) 2. 03:02 PM - Re: -7 tipup rear window fitting problem (Trevor) 3. 06:28 PM - Re: -7 tipup rear window fitting problem (Charlie England) 4. 08:02 PM - Consensus On Finishing Back End Of Fiberglass Tips... (Matt Dralle) ________________________________ Message 1 _____________________________________ Time: 12:07:50 PM PST US From: Charlie England Subject: RV7-List: -7 tipup rear window fitting problem I'm beginning the fit of my rear window (-7 tipup). After the big cut & trimming the rear window to the plans-specified 1 1/4" outside the top skin outline, I get a good 'glass/skin fit from top rear to about 10" back of the roll bar. from that point it looks like the skin is puckered out, but on closer exam the bottom edge of the window doesn't curve down & in quick enough & is slightly outside the vertical line of the fuselage side. The problem is almost identical on both sides. I *might* be able to pull this in with screws, but my plan is to glue the canopy and the rear window. I've got misgivings about expecting the sikaflex to hold against this much stress when it won't be the specified 1/8" thickness around this curved edge. Has anyone else seen similar problems, and what did you do? The 1st thing that comes to mind is heating & re curving the plexi, but the 2nd thing that comes to mind is needing a new $1K canopy. Thanks, Charlie ________________________________ Message 2 _____________________________________ Time: 03:02:39 PM PST US From: "Trevor" Subject: Re: RV7-List: -7 tipup rear window fitting problem I used some sawn off broom sticks with foam padding to push the plexi from the inside of the cockpit against the skin. I used about 5 and wedged them onto the floor. This squeezes the Sika out- no problem tho as you can mask off an area 1/4-3/8" beyond the plexi, prep it as per instructions, and run a bead of Sika along the aft edge of the plexi, This makes a neat fillet and gives it the holding strength. The thin gap on the outside, between the skin and plexi can be neatly finished by masking off about 1/8" from the edge of the skin and onto the plexi and filling with tank sealant. Use finger to smooth it off. Don't be too fazed by the min 1/8 gap as the coverage is over a large area and although the plexi is almost flush with the skin on the outside, there is a slight taper away from the skin the further aft the plexi extends, which will be filled with a thicker layer of Sika. I was amazed with the result. The plexi pushes the skin outwards and fits snugly -no holes, no puckering, no waves and ugly screws/rivets etc. I also made the gap between the front and rear canopy slightly larger and built in a _n_ seal. This solved the problem of having to raise the rear canopy up 1/8 and finding the front part without any support. Used some square self-adhesive 1/8 rubber door seal to form a "dam" which I filled with Sika, some vaseline on the front Plexi, closed the canopy and when the excess was hard I meerly sanded it flush, leaving a neat air-tight seal. Obviously you need to apply electrical tape to mask/protect the areas you dont want Sika on. hope this helps- feel free to contact me if you need any explanations Trevor RV-7 Tip up + RV-7 slider with only Sika - sorry, one hole on the slider for the locking handle! ----- Original Message ----- From: "Charlie England" Sent: Thursday, August 07, 2008 9:07 PM Subject: RV7-List: -7 tipup rear window fitting problem > > I'm beginning the fit of my rear window (-7 tipup). After the big cut & > trimming the rear window to the plans-specified 1 1/4" outside the top > skin outline, I get a good 'glass/skin fit from top rear to about 10" back > of the roll bar. from that point it looks like the skin is puckered out, > but on closer exam the bottom edge of the window doesn't curve down & in > quick enough & is slightly outside the vertical line of the fuselage side. > The problem is almost identical on both sides. I *might* be able to pull > this in with screws, but my plan is to glue the canopy and the rear > window. I've got misgivings about expecting the sikaflex to hold against > this much stress when it won't be the specified 1/8" thickness around this > curved edge. > > Has anyone else seen similar problems, and what did you do? The 1st thing > that comes to mind is heating & re curving the plexi, but the 2nd thing > that comes to mind is needing a new $1K canopy. > > Thanks, > > Charlie > > > ________________________________ Message 3 _____________________________________ Time: 06:28:32 PM PST US From: Charlie England Subject: Re: RV7-List: -7 tipup rear window fitting problem Thanks for the info. My problem might be the reverse of yours: the outside/bottom edge of the plexi about 8-10" behind the roll bar, where the top skin starts its sweep up as well as back, is actually wider than the fuselage in that area. The result is that there's a small but noticeable gap between the plexi & the curved edge of the top skin. The edge of the plexi, 1 1/4" below the edge of the skin at that point, is pushing the skin out. There isn't enough curvature in the window to take that area vertical to match the skin's 'desire' to be vertical in that area. Therefore, the ~4" wide area of the skin leans outboard at the top if it's cleco'd along the longeron rivet line. It's not bad, maybe 1/16-1/8" at the worst point, but if there's a way to make it really fit I'd like to try it. Charlie Trevor wrote: > > I used some sawn off broom sticks with foam padding to push the plexi > from the inside of the cockpit against the skin. I used about 5 and > wedged them onto the floor. This squeezes the Sika out- no problem > tho as you can mask off an area 1/4-3/8" beyond the plexi, prep it as > per instructions, and run a bead of Sika along the aft edge of the > plexi, This makes a neat fillet and gives it the holding strength. The > thin gap on the outside, between the skin and plexi can be neatly > finished by masking off about 1/8" from the edge of the skin and onto > the plexi and filling with tank sealant. Use finger to smooth it > off. Don't be too fazed by the min 1/8 gap as the coverage is over a > large area and although the plexi is almost flush with the skin on the > outside, there is a slight taper away from the skin the further aft > the plexi extends, which will be filled with a thicker layer of Sika. > I was amazed with the result. The plexi pushes the skin outwards and > fits snugly -no holes, no puckering, no waves and ugly screws/rivets etc. > > I also made the gap between the front and rear canopy slightly larger > and built in a _n_ seal. This solved the problem of having to raise > the rear canopy up 1/8 and finding the front part without any > support. Used some square self-adhesive 1/8 rubber door seal to form > a "dam" which I filled with Sika, some vaseline on the front Plexi, > closed the canopy and when the excess was hard I meerly sanded it > flush, leaving a neat air-tight seal. Obviously you need to apply > electrical tape to mask/protect the areas you dont want Sika on. > > hope this helps- feel free to contact me if you need any explanations > > Trevor RV-7 Tip up + RV-7 slider with only Sika - sorry, one hole on > the slider for the locking handle! > > ----- Original Message ----- From: "Charlie England" > > To: "RV list" > Sent: Thursday, August 07, 2008 9:07 PM > Subject: RV7-List: -7 tipup rear window fitting problem > > >> >> >> I'm beginning the fit of my rear window (-7 tipup). After the big cut >> & trimming the rear window to the plans-specified 1 1/4" outside the >> top skin outline, I get a good 'glass/skin fit from top rear to about >> 10" back of the roll bar. from that point it looks like the skin is >> puckered out, but on closer exam the bottom edge of the window >> doesn't curve down & in quick enough & is slightly outside the >> vertical line of the fuselage side. The problem is almost identical >> on both sides. I *might* be able to pull this in with screws, but my >> plan is to glue the canopy and the rear window. I've got misgivings >> about expecting the sikaflex to hold against this much stress when it >> won't be the specified 1/8" thickness around this curved edge. >> >> Has anyone else seen similar problems, and what did you do? The 1st >> thing that comes to mind is heating & re curving the plexi, but the >> 2nd thing that comes to mind is needing a new $1K canopy. >> >> Thanks, >> >> Charlie >> >> >> >> ________________________________ Message 4 _____________________________________ Time: 08:02:49 PM PST US From: Matt Dralle Subject: RV7-List: Consensus On Finishing Back End Of Fiberglass Tips... Dear Listers, Here are some pictures of my recently finished Fin and Rudder fiberglass tips, specifically highlighting my notion of mounting the VOR/GS/LOC antenna on the top of the Fin. It came out very nice I think and gives full access to cabling and antenna mount for maintenance. But here's my question. Look at that last picture of the back end of the Fin fiberglass tip and note the gaping hole. I gather from the plans that it is kind of up to the builder whether to put a cover on the back of it. My first question would have to be why the f*** isn't there one already molded on it like on the front of the rudder tip? But, hostility aside, what's everyone's thoughts on finishing these? I'm just thinking that my patience for fiberglass layups hovers around zero and I can just see taking a totally sweet tip installation and mucking it royally. But, I will if I must. I would really like the back end finished off rather than gaping open like that, but it might be something I could live with... Thoughts? Matt Dralle RV-8 #82880 ------------------------------------------------------------------------------------- Other Matronics Email List Services ------------------------------------------------------------------------------------- Post A New Message rv7-list@matronics.com UN/SUBSCRIBE http://www.matronics.com/subscription List FAQ http://www.matronics.com/FAQ/RV7-List.htm Web Forum Interface To Lists http://forums.matronics.com Matronics List Wiki http://wiki.matronics.com Full Archive Search Engine http://www.matronics.com/search 7-Day List Browse http://www.matronics.com/browse/rv7-list Browse Digests http://www.matronics.com/digest/rv7-list Browse Other Lists http://www.matronics.com/browse Live Online Chat! http://www.matronics.com/chat Archive Downloading http://www.matronics.com/archives Photo Share http://www.matronics.com/photoshare Other Email Lists http://www.matronics.com/emaillists Contributions http://www.matronics.com/contribution ------------------------------------------------------------------------------------- These Email List Services are sponsored solely by Matronics and through the generous Contributions of its members.