The Wait is Over

[jiott]

That scalloping idea is interesting. I'm anxious to see how it looks when covered.

[Paul Z]

I'm looking forward to seeing it in person, maybe I need to fly over for Cooperstate.

[DesertFox4]

It looks great Jim. Already seen a couple done that way.

Thanks for the truckload of LIKES Chase.

[bbs428]

Great thread. Enjoying your progress and following along.

Pic's are informative for us "visual" learners. LLE is coming along nicely.
I'm still debating to do this mod on my wings. I agree that it does look better.

[Paul Z]

I thought the LLE wrapped under the wing as far as it does over the top. I definately learned something via your post. I'd love to add that feature to my plane but it would require re-registering mine as an ELSA and a lot of work.

[DesertFox4]

Laker Leading Edge is all bonded in place. My day started off early with washing the four sections of leading edge with water for about 20 minutes each. Thoroughly clean off any release agent residue still on the parts from production. Very slippery stuff that release agent when wet. It would interfere with a quality bond if not washed from the parts. No picks of that process. I ended up with wet tennis shoes somehow.

After a quick drying in the Arizona sun, I roughed up the bonding areas with 150 grit sand paper to provide a little extra "tooth" for the adhesive and the fiberglass.

The fuel tanks were also given some "tooth" as well as lightly sanding the ribs for the same reason. A thorough cleaning of all bonding areas with 99% rubbing alcohol made sure nothing would interfere with the bond.


Here is where it gets interesting. This is likely the first installation of a LLE using 3M's 850 adhesive instead of the usual HySol epoxy bond. This is the same product I believe that Kitfox uses on the flaperons now to bond the trailing edges with good success and is used extensively in the auto industry and hundreds of other manufacturing processes for strong secure bonds. It stays slightly flexible when cured unlike HySol but retains a very strong bond. In the first photo you see Bill showing us the proper application and locations on the wing for best strength on the first of four sections of LLE. I applied the other 3 sections duplicating what was demonstrated on the first section. It went very quickly compared to using HySol. Likely less weight also for a superior bond.
IMG_1230.jpg

In this photo you see the bonded section in place and now we tape. Taping down the scallops very lightly so as not to distort but get a good spread of the adhesive. Also the tails of the scallops were taped at each false rib with cleco's used in the ribs to assure exact alignment. It went very well. The other 3 LLE sections will shortly receive the same fate.
IMG_1231.jpg

We quickly ran out of the yellow and green tape and settled on good old masking tape for most of the rest of the sections. Looks more uniformed and professional to have matching tape everywhere.
IMG_1233.jpg

Here you can see the finished bonding process. Being opaque, the LLE let us see any spots that may need "fixing" with adhesive before it was finalized. I fixed a couple like a portion of the first false rib in this photo.
3M 850 was great to work with.
IMG_1234.jpg

The holes drilled for the cleco's will be filled with Super Fill when curing is complete.
IMG_1235.jpg

The underside of the wing is shown in this photo.
IMG_1241.jpg

This photo shows the fuel tank end of the wing.
IMG_1236.jpg

[Paul Z]

Looks so simple when done by one of the experts.

[DesertFox4]

Well, two of the three of us really are experts. Can you guess which one I am.

Yep, the rookie. I'm only on my 2nd Kitfox. Between the 3 of us I think we're approaching double digits.

[DesertFox4]

Just a note: this product does have an expiration date so it does not have the same shelf life as the method currently used for bonding the LLE. It also takes much longer to cure than HySol although application goes faster. Kind of a trade off I guess. We figured just to be cautious a full week on the cure with wings in the vertical position on the wing rotisserie before removing the clecos and tape. Most wouldn't probably want to wait that long to move to the next process so HySol still looks like the best viable bonding method.

I won't be back to the shop until this weekend to find out where it may be purchased and most importantly to see what kind of actual bond I have on the LLE.
I know Kitfox Aircraft does not provide it for re-sale.


Caveat follows:
I am in the experimental mode on this guys so if you want to bond your LLE and never give it another thought when flying, use the proven method. I will let you know if this is a viable alternative but that won't be for some time yet.

[DesertFox4]

Sat. & Sunday spent doing lots of final sanding on wings before covering.
Dan B. stopped by on Sat. to lend a hand with the LLE to tank transition. He did a great job.
IMG_1256.jpg



Ran the pitot tubing as shown.
IMG_1253.jpg

No drilling in the spars or running it way out to the wingtip and back through the spar. Drilled the one hole in the rib and tucked it in behind the fuel tank.
IMG_1252.jpg

Installed the pitot tube inboard one rib so it is protected from damage by the struts. I did the same thing with my model 4 and it worked great and never any hat damage at fly ins or airshows.
IMG_1251.jpg

Just about ready for covering.
IMG_1269.jpg




Painted the inside of my baggage compartment black.
IMG_1261.jpg

Wings ready for covering. One last look before they go under cover.
I think they are beautiful wings. Lots of loving care has gone into these. I hope they fly as good as they look.
IMG_1270.jpg

Bonded in a piece of birch in the left outboard wing for future AHRS mounting accessible through the wingtip.
IMG_1249.jpg