Wing Root Fairing Help

I'm having a difficult time coming up with a wing root fairing that I like.... I'm talking about the leading edge fairing at the wing root to windscreen intersection. What have others done? Pictures would be great!

Thanks

I had the same dilemma, when I replaced the windscreen on my KF3, I didn't want to put the aluminum fairings back on. So, I made some out of composite. Here are a few photos of the process of making them in place.

I first covered the area with clear packing tape to act as a releasing agent.

Attachment 11011

Next, using modeling clay, I shaped the fairing to look like I wanted it.

Attachment 11010

I then did the lay up with 2 layers of glass, the filled with micro to shape the surface.

Attachment 11008

This is the result, in prime, ready for final paint.

Attachment 11009

Very cool step by step with pictures! Dumb questions since I've never worked with fiber glass: Is the clay removed before you do the lay-up? And which side of the clay do you apply the fiber glass? (I'm thinking to the bottom side...) Thanks..

That is a very neat solution. I thin that Ben - (Macaero) has made some really nice CF ones too - got some details Ben?

r

I saw the pictures of the carbon fiber work, it looked real nice and smooth... I am not that good yet. The fiberglass is more forgiving allowing to smooth the surface with micro. My process was as follows, I will try not to leave anything out.

As you can see in my first picture, I covered the area with clear packing tape, duct tape would work also, it's purpose is to act as a shield/release agent for the underlying surface.

Next I used modeling clay (I bought 2lbs on Amazon, used less than half of one package.) The clay is used to build up the area to the shape you want. I used the 3/8 drive extension you see laying above the work as a roller to smooth the clay, I also used a long socket (3/4 or larger) to roll out to a smoother transition. Whatever imperfections in the surface will be in the initial layup.

The wetted fiberglass is laid on top of the clay, cut to shape, I used two plys. I drew onto the tape on the wing and windshield the shape I wanted the fairing to cover, then laid a sheet of polypropylene plastic to trace the shape onto, I then used that as a template to cut the dry glass fabric. I then wetted the shaped fabric out on a square of plastic, laid another layer of glass on and wetted it, then laid another piece of plastic on it forming a sandwich and squeegeed out any excess resin. this was laid onto the formed surface, directly onto the clay and smoothed out. Let the resin set.

I removed it, the clay may stick to the back of the piece, simple scrape it off and clean the backside. When releasing the piece from the tape use compressed air blown under the piece to get it to lift, being careful not to use too much force that you will bend it. I then dressed the edges a bit, drilled the holes (one on top and one on bottom to mount. I am using nut plates epoxied to the inner side of the flange of the root rib. Using clecos to hold it in place I used a mixture of micro balloons and epoxy mixed to a consistency somewhere between toothpaste and DAP spackle to fill the weave and smooth the imperfections of the surface. When this was about where I wanted it. I added another layer of glass (not really needed) then filled the weave again.

These fairings will have to be removed to remove the wing pin (I keep my Kitfox in a hangar and don’t need to fold the wings). I didn't want access holes in top and bottom like the aluminum ones in the plans. To attach I am using #8 flat head machine screws with stainless tinnerman washers from Aircraft Spruce Catalog.

That was my process. I have not completely finished, but so far I like the results over the old aluminum fairings.

Ralph

I believe you lay the fiberglass over the clay, while the clay is still in place on the wing & windshield.

I don't have good pictures to show of mine right now, but after I did my aluminum wing root fairings I wondered why everyone doesnt do theirs like I did mine?

I started by using posterboard to make a template that basically made a 3 inch wide strip all the way around the top of the cabin plexiglass (rear, left and right sides). I contined it around and under the leading edges back about 6 inches from the leading edge. It was pretty simple by making them in three pieces for the top of the wing and leading edges, and two separate pieces for the bottom of the wing.

(Note:this is just flat aluminum. There are no curves or bending. The flat of the aluminum butts up against the plexi by the leading edge. I don't have any rubber edging on mine, but that could be used if you have concerns about the aluminum rubbing against the plexi)

The aluminum fairings stay in place for wing folding, and because they are wide they completely cover the butt rib gap, and they make a nice tight fit around the cutout and curved area of the windshield near the wing pin area (the area that typically cracks or at minimum has stress lines in it). Originally I did this because my Kitfox had some bad cosmetic issues with the plexi windshield near the wing pins and on the rear corners. So this was my solution to cover all that up. It looks very custom, and is really easy to do. Obviously they could be painted to match, but I kinda like mine matching the spinner. One day when I have noghing better to do I just might polish those fairings to a chrome finish...

I will try to get some better pictures this week, but hopefully in the meantime this picture will give you the general idea I was trying to explain.

Ok, here are more pictures. Note how simple this is to do. You already have screws holding windshield in place, so this trim is just held in place with the same screws. And I think it is only ounces of added weight vs pounds. I'm guessing it is only slightly more than the fibreglass pieces shown in this thread.

Oh, and for the record, I'm making new pieces for the bottom of the wings, that's why you don't see those here. (And yes, I know I'm missing one screw on the left front corner of windshield).

In the 4th pic down, is that a shadow I am seeing or do you have a piece of rubber inside the fairing?
Thanks

Lou

I put some black camper tape on the wing so that when going into the aluminum trim it seals tight to keep air and water out, helping to make cabin much less drafty too. I had wings folded earlier this season, but I typically also have a one inch round piece of clear tape over the wing pin holes so it doesn't rain in. I need to put those back on for the season as I sometimes leave my Kitfox on the beach in front of my house for a week or two at a time, including during rainshowers.

Paul,
I really like your approach!!

What thickness of aluminum did you use?

Thank you for sharing your great approach!! (Yes, I will copy it!! Lol!!)

Thanks,
Grover

Mike,
The first picture shows the template that came with the kit at the left. Next is the template that I ended up with which is quite a bit wider, then the finished product.
I found that by making the fairing wider, I had an easier time making a smooth transition to the wing.

Quote:

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Originally Posted by GWright6970

Paul,
I really like your approach!!

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Glad you liked it. I'm not 100 % sure, but I believe it was some scrap .016 I had laying around. But any reasonable thickness will work. It just has to be thin enough to be able to bend easily over the leading edge.