Wing Fabric

For general discussion of the Just Aircraft family of aircraft.
Includes: Highlander, Escapade, Summit and SuperSTOL.

Moderator: scubarider2

Wing Fabric

Postby jjacky » Sat Dec 20, 2014 11:22 am

Merry Christmas and Happy Flying you Just Plain Crazies
I'm sitting here looking at some Highlander wings all ready for fabric and it is intimidating. Especially the bottom. Margie and I (mostly Margie) have used the Stewart system and have done well fabricing the flaps and ailerons but I'm concerned about the concave bottom of the main wings. Do you glue everything down to the ribs, partially shrink,rivet, full shrink and tape OR partially shrink, glue, rivet.......I'm at a loss here...also..
how do you handle the trailing edge. Does the bottom fabric go around the bottom, up to the top and over, where it'll be glued and taped to the top fabric....or what ...
And one last thing, I need to double check my temperatures. What are you using for the first shrink...second shrink...etc,,,,need some advice...Thanks!
Plan not to be the first at the scene of the accident!
jjacky
Veteran Member
 
Posts: 215
Joined: Wed Aug 19, 2009 12:07 pm
Location: Greensboro, NC

Re: Wing Fabric

Postby gkremers » Sun Dec 21, 2014 4:34 pm

OK.. Didn't see any replies so thought I would tell you what worked for me. I was concerned also with the lower wing surface. I used Stewarts also and didn't have a problem. Glue down each rib cap strip and of course wrap the fabric around the inboard and outboard rib. On the trailing edge the fabric covered about two thirds of the aluminum. When I did the upper fabric it overlapped the trailing edge aluminum two thirds again (over the lower wing fabric). Let the glued fabric dry over night. The first shrink is at 250 degrees, alternate the panels per the Stewart instructions (probably the same as Super Flight) to be sure the shrink is even. After all the fabric is shrunk to 250 on the bottom surface I moved to the upper surface. On the upper surface you do not need glue on every rib cap strip. I only applied glue to outside edges. Shrink the upper surface to 250 degrees. Move back to the lower surface and shrink to 280 or so. I didn't go any further with the temp on the lower surface. At this point you can burn the holes in the rivet holes, apply the reinforced tape and re-burn the holes. Rivet all the lower ribs and then move to applying the finish tapes. Move to the top surface and finish, the upper wings were shrunk to 300, I did shrink the upper surface that was in the prop blast to 325. Burn holes, apply reinforcement tapes, re-burn holes and rivet. Apply finish tapes.

DSC_0344.JPG
Lower wing after first shrink


DSC_0349.JPG
Rivet holes burned on lower surface


DSC_0022.JPG
rivet holes burned in lower surface after reinforcement tape


DSC_0038.JPG
Upper surface before first shrink


DSC_0011.JPG
Upper surface after first shrink


DSC_0040.JPG
Upper surface with rivets before finish tape



Gary
N325AB On Skis now!!
User avatar
gkremers
Veteran Member
 
Posts: 403
Joined: Sun Aug 08, 2010 8:06 am
Location: Michigan

Re: Wing Fabric

Postby jjacky » Sun Dec 21, 2014 8:24 pm

Gary That is perfect...Thanks a ton!
Plan not to be the first at the scene of the accident!
jjacky
Veteran Member
 
Posts: 215
Joined: Wed Aug 19, 2009 12:07 pm
Location: Greensboro, NC

Re: Wing Fabric

Postby User GDS » Mon Dec 22, 2014 12:39 pm

I couldn't remember how I covered the wings until gkeremers posted, I did the same thing. Two additional notes;

I started the bottom piece of fabric on the top of the wing, at the line where the aluminum leading edge meets the spar, terminating it on the trailing edge as described above. The top piece of fabric was started on the bottom of the wing, where the ribs meet the spar.

I bonded a capstrip to the bottom of the fuel tank so that it would look consistent with the rest of the bays on the bottom of the wings. Since I couldn't rivet that section, after about 100 hours the adhesive came loose and the fabric is no longer attached to the capstrip. It's not a problem, but if I had it to do over I would skip the capstrip idea.
GDS
So Cal
Highlander #232
Rotax 912ULS, Dynon Skyview
User GDS
Veteran Member
 
Posts: 304
Joined: Sun Jul 01, 2012 11:59 am
Location: Big Bear Airport

Re: Wing Fabric

Postby gkremers » Mon Dec 22, 2014 2:20 pm

Good points on where to start the fabric. I also installed a 6" finish tape wrapped around the leading edge.

So far the false rib under the fuel tank is holding up fine. When running a straight edge from the inboard rib to the first rib outboard of the tank it was not even. You can tell from the pic I needed to build up the rib on either side of the false tank rib. Just added another cap strip and blended them it.

DSC_0293.JPG


Gary
N325AB
User avatar
gkremers
Veteran Member
 
Posts: 403
Joined: Sun Aug 08, 2010 8:06 am
Location: Michigan

Re: Wing Fabric

Postby FlyerChief » Mon Dec 22, 2014 3:35 pm

The bottom of my tanks ended up flush with the ribs, so I eliminated the cap strip.
On the recommendation of Stewart Systems, I wrapped from the bottom of the front spar, over the wing and terminated it at the back of the wing, then started the second piece at the back and then wrapped it under and back over the front, overlapping and gluing the entire leading edge wrap, terminating it at the back of the false ribs. It makes for a nice clean leading edge with no need for extra tapes there. I did add an extra tape along the back of the leading edge wrap for added protection along the edge. The fabric is glued to the bottom of the tanks, again at Stewart Systems recommendation. I don't think this method would work well though if there is no leading edge wrap.
Dan
Highlander #241

20121230_092233.jpg


20121230_092120A.jpg
When everything seems to be going against you, remember that the airplane takes off against the wind, not with it. ~Henry Ford
User avatar
FlyerChief
Veteran Member
 
Posts: 261
Joined: Tue Nov 03, 2009 9:53 pm
Location: Ontario, Canada

Re: Wing Fabric

Postby gkremers » Mon Dec 22, 2014 9:30 pm

Dan,
I had Just install the tanks, if the fabric was glued down on the bottom of the wing it would have looked pretty bad with a big depression. Yours looks nice as the tank was flush. The fabric on top of the tank was indeed glued down on the entire surface.

One other thing to think about is the fuel cap area. Steve posted something a couple of years ago about gas getting into the glue near the cap and lifting the fabric. He had to repair his. I was concerned about it and spoke with Stewart. They agreed the best protection was to cut the fabric away 1-1.5" away from the cap. I did that and took all the glue off that was under the fabric. The Eco prime was applied right up to the cap. After a few coats it blended in pretty nicely. Stewarts also recommended spaying an automotive primer over the Eco prime near the fuel cap area.


jjacky.... Lots of way to skin the cat....good luck and let us know how you make out.
Gary
User avatar
gkremers
Veteran Member
 
Posts: 403
Joined: Sun Aug 08, 2010 8:06 am
Location: Michigan

Re: Wing Fabric

Postby Jack L » Mon Dec 22, 2014 9:57 pm

Gary,
Like you I was concerned about the fuel cap area and spoke to Steve about it. After discussing options with Steve I decided to try something a little different and kept the fabric tight to the fuel cap and applied fuel resistant Pro Seal over the cap flange and fabric. This picture was taken right after painting and prior to installing the vent tube, so far so good.

Jack

366.JPG
Jack L
Veteran Member
 
Posts: 104
Joined: Sun Apr 27, 2014 12:10 pm

Re: Wing Fabric

Postby gkremers » Mon Dec 22, 2014 11:07 pm

Jack,
Very nice job!

Gary
User avatar
gkremers
Veteran Member
 
Posts: 403
Joined: Sun Aug 08, 2010 8:06 am
Location: Michigan

Re: Wing Fabric

Postby Jack L » Tue Dec 23, 2014 6:38 am

Thanks Gary,

The idea came to me when I saw the pictures of your RV windshield in a windshield sealing post. Pro-Seal or PRC is used extensively in aviation and I had some that was about to expire so I tried it. PRC is a one step procedure versus the multiple steps required to apply automotive primer and paint and at the time I was not having fun with the paint and did not want to further complicate things. The PRC should work well in this application but only time will tell.

I have been thinking about sealing my windshield with PRC but wanted to ensure there were no serious electrical problems before doing that. Do you plan to seal yours?

Jack
Jack L
Veteran Member
 
Posts: 104
Joined: Sun Apr 27, 2014 12:10 pm

Re: Wing Fabric

Postby gkremers » Tue Dec 23, 2014 8:40 am

Jack,
I do plan on sealing the it the same way as the RV. It's a good winter project.

Gary
User avatar
gkremers
Veteran Member
 
Posts: 403
Joined: Sun Aug 08, 2010 8:06 am
Location: Michigan

Re: Wing Fabric

Postby jjacky » Tue Dec 30, 2014 12:31 pm

Guys Thanks for your ideas...this is great!
Plan not to be the first at the scene of the accident!
jjacky
Veteran Member
 
Posts: 215
Joined: Wed Aug 19, 2009 12:07 pm
Location: Greensboro, NC

Re: Wing Fabric

Postby moving2time » Thu Jan 08, 2015 5:13 pm

I always thought that the fabric was above both the top and bottom of the tank. The photos of FlyerChief's fabric glued to both surfaces of the tank look like a beautiful finish to the flush fuel cap. I plan on installing the flush cap on my wing and it is an area that I figured I would need to figure out when the time came. These photos are awesome and very enlightening. However, it sounds like the tank has not fared to the rib profile quite so well in all cases. I guess I am surprised that the tanks would be so different. Joe B
moving2time
Veteran Member
 
Posts: 201
Joined: Fri Oct 15, 2010 5:42 pm

Re: Wing Fabric

Postby FlyerChief » Thu Jan 08, 2015 8:35 pm

Hi Joe,
My tanks may have been installed just a little bit lower than they were installed on other planes. I assume the fiberglass tanks were done in the same mold, but there can be a slight variation.
Here's how I faired my leading edge to the tank. The curve gave it a nice transition and doesn't create a visible line or single stress point, like it does when terminated at the rib.
Dan
Bondo and Putty.jpg
When everything seems to be going against you, remember that the airplane takes off against the wind, not with it. ~Henry Ford
User avatar
FlyerChief
Veteran Member
 
Posts: 261
Joined: Tue Nov 03, 2009 9:53 pm
Location: Ontario, Canada

Re: Wing Fabric

Postby gkremers » Fri Jan 09, 2015 3:00 pm

I agree. The tanks are not exactly the same and installation varies. Just installed the leading edge and the tanks on mine. The tanks were flush with the upper surface of the wing and recessed about 3/16" on the lower side. The instructions from Just have you glue the fabric down on the top side and install the false cap strip on the bottom so the fabric never touches the fiberglass on the lower side. Per the instructions from Stewart System my fabric is glued down to the leading edge aluminum and the upper surface of the tank.

It looks like Dan was able to glue both upper and lower to the tank. You can see from the picture the upper surface of my wing was flush with the tank, not much Super Fill required.

Either way will work, it all depends on tank thickness and how it's installed.

DSC_0252.JPG


Gary
User avatar
gkremers
Veteran Member
 
Posts: 403
Joined: Sun Aug 08, 2010 8:06 am
Location: Michigan

Next

Return to Just Aircraft

cron