Chapter 20 
Winglet & Rudder Construction


I won't go into the mechanics of hot wiring the winglet cores, as I did those the same time I did the wing cores. I must say here , a number of builders pay other people to provide cores for them. But I made it through that part of construction with a minimum of mistakes, and a maximum of money saved. And hot wiring was fun!!!.  It also taught me Epoxy Woman, (my wife), works best when the level of my voice is kept at non-deafening levels. A lot of people spend a lot of money in Marriage Counseling to learn

So anyways... here's a pic the torroids on the coax. (I used the stranded coax from Wicks after much wasted research.)

I decided to cut slits into the foam and insert the copper tape into the foam. No worries about the "possible" infamous de-lamination problems. I did the NAV antennas the conventional way, but could see no real reason to do it the same way for the COM due to their omnidirectional nature. Hope this mod doesn't come back to bite me in the butt!.

Later note: I was really pleased with the final product. No bumps over the antenna.

I drilled a hole from the leading edge to the center of the antenna, then used the Proxxon, (Cadillac of Dremels), to route a channel to the base of the winglet. After routing the coax, I Pour-foamed the trough, then sanded smooth.

Later note: after performing this step, I came across a good technique posted in Wayne Hick's site for using Pour Foam. It involves lining the foam around the area you are repairing with duct tape, then pouring the foam. The slide a hacksaw blade along the surface. The duct tape serves to protect the surrounding foam. I'll post pictures after using this technique later in the Turtleback section.

The glassing of the winglets went a lot like the wings, (with the exception of the winglet tips. But If you've made it this far, I'm sure you have the technology to figure this out.). If it's been a while since you've done the wings, you may want to review that chapter, because the plans don't repeat themselves here.

I won't be attaching them until I get the wings mated to the Main Spar. So for now, I'l store them with the canard and wings. Everything I've been reading about that operation pretty much means a weekend is needed for setup and completion.

Ala' Wayne Hicks, I used the wing cut off part to help support the winglet durIng the attachment phase. Yes... It's held on w/drywall screws.

The WPRP measurements weren't all that hard. I was able to do it myself with the help of a standing floor brace which was originally made to hold the spar cap tape spool when I was making the canard/wings.

Later note: I did the inboard layup before flipping.

It worked real well.

All braced and ready to flip. I think I'm going to do the inner/upper layup first before flipping. Can't really see a reason not to.

On the second winglet, I used stir sticks sharpened in the grinding wheel, then stuck into the foam beneath the wing skin. (Technique stolen from a forgotten source.)

It worked as well as screwing the cutoff piece back on with drywall screws. Maybe a little better.

This is the best shot I have showing the "Racetrack" look you get after properly contouring the foam between the outer winglet skin and the lower wing skin.

The layups were pretty straight forward here. It's truly amazing how firm/strong the end result is here

At right,  you see the hidden rudder belhorn... which I think I made about 30 years ago.

Due to the angle of the hinge-line, the end of the horn will travel @3/8" upward as seen (or downward if you have the wing right-side up.)
Make sure you set it appropriately. It probably isn't perfect, but I'll be able to gently bend it later on to get it just right.

Make sure you remove plenty of foam for the space required for the bell horn to move. It will save tons of time performing arthroscopic surgery later on.

The final product. I carved a wedge to mostly fill the void between the upper and lower winglet, filled the rest of the outboard side w/micro. On the inner aspect, I squirted some Pour Foam and sanded to form. One ply of BID later it was done.

Here's the rudder cutout and readied for close-out glassing. You can see the small void below the bottom-half of the bellhorn. This got filled in with foam and micro prior to glassing.

 My ultimate goal is to have a totally clean look to the rudders. No visible fasteners whatsoever. I'm using ClickBond studs going in from the outside. Because of the close quarters in the hinge area, I felt getting nuts on the ClickBonds would be very cumbersome at best and likely impossible at worst. To get around that problem, I'm going to install the nuts on the hinges/rudder/winglets with the hingepin removed, and use a single long hingepin to install/remove the rudder when necessary

I decided to give carbon hinges a try. has a ready-made product that has worked very well so far. They are easy to shape and drill. Delivery time was prompt, and the manufacturer was always there to answer questions regarding the use of their product.

Above, you see the Carbinges held with Clecos. The wire you see coming from the top if the winglet is the hinge pin with the keeper on the end. When completed, the keeper will be floxed in and the pin will be held in by a internal allen screw silver soldered onto the hinge pin. (Clear as ketchup, right?)

And above, is your first glance a winglet assembly with no visible fasteners or bellhorn.

So far, have about 1/8 of an inch gap between the router in the winglet.  At this point in time, I have about 28° of rudder travel when fully deployed. Hopefully, I'll be able to keep that clearance after filling and finishing.

If I haven't mentioned it before, I'm using Click Bond bases.  I've drilled a hole or two and ground a couple of notches in the perimeter of each base to keep them from turning when I tighten the nuts.

To the left, we have the rudder installed, complete with hidden rudder bellhorn, carbon hinges, and NO hinge screws. (AND 30 degrees of travel... but we'll see how much that gets reduced when I install the attachment hardware.)

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