Kitfox Covering Continued...

Helped Terry put the left side on the Kitfox this morning. No big issues. Went on pretty straight with a few wrinkles for him to work out tomorrow during the final shrink. All that is left is the top and the vertical stab.

Control Cables Continued...

Finished up rigging the Aileron cables today. The first order of business was to block up the control sticks, centered, preventing any movement. This is necessary so I can pull on the cables to get them taught before swagging. I already had the ailerons themselves blocked up in neutral position.

I ran the aileron cable from the wing root around the top pulley and down through the fairlead. Then I swagged the turnbuckle onto it. Next, I cut a length of cable and swagged a shackle on one end. I fit that end on the control sticks. Ran the other end around the front pulley back through the frame to the rear pulley. I swagged that end to the turnbuckle to complete the connection.

The hard part on swagging the sleeves is to get the cable tight while doing it. It takes a bit of effort and three hands to do it. For the third hand, I use needle nose vise grips with rubber fuel line pieces fit over the jaws so I don't damage the cables. I lock the vise grips on the cable after I've pulled them as tight as I can get them by hand to lock them in place while I wield the big crimper tool. The initial crimp is critical as it will hold everything in place, but if you get it wrong it's disastrous as it can't be removed and requires cutting the cable. This may require a whole new cable to be fashioned. Get it right the first time!

I then moved on to the cross aileron cable connection. Each cable exits the wing root and connects to each other at the rear of the head rack. These cables get connected directly together via another turnbuckle. The problem with this connection is that it is at the top of the head rack on the center line of the aircraft. Not easy to reach. I used a couple of vise grips as before to get the cables through the turnbuckle and sleeves and to hold them in place while I adjusted them to center the turnbuckle on the center line of the aircraft. Once I was happy with the alignment I swagged one side to set the position. I then pulled the cables as tight as I could and set the other side. This allowed me to remove the vise grips (and their weight) from the cables. I then completed the rest of the crimping.

A little trick was to loosen the turnbuckle a few turns while pulling the cables tight before crimping. I did this because I knew I couldn't get it as tight as needed with the vise grips weight pulling down on the cable. The weight created some slack that I could not remove while crimping. After I crimped everything I re-tightened the turnbuckle back to it's neutral position which pulled any slack I had in the cable back out. This put me right where I wanted to be, tight cables in the neutral position.

The last task for the day was to rough cut out the slot in the side seat trim piece for the aileron cable pass through. I decided to see if the passenger side slot would fit on the pilot's side if I flipped it, it fit perfect. So, I use it as the template, laid it on top of the pilot's side piece and traced out the slot. I then proceeded to nibble it out with the nibbler tool. I verified the fit and it was right on, so I'll finish final sanding and filing tomorrow.

Control Cables Continued...

Started working on the Aileron connections today. Before I could make up the connections from the control stick to the turnbuckle, I had to make a cable pass through in the side panels next to the seat. Took a little while to figure out how I wanted that to look. Anyway, after a several hours of trial and error, I came up with the following "slot". This works well and looks pretty good too.

However, I am thinking I would like to design some type of cover to go over this cable and slot to prevent anything from falling into and jamming the free travel of the cable. I will think about this over the next few days.

Now to do the same on the other side.

Control Cables

I started making my control cables today. The manual is again weak in this area. It does specifically state to measure out two eight foot pieces for the flaps. No other measurements are given for the rest of the cables. So, I measured out and cut the two eight foot cables.

Then the head scratching began. No part numbers are given, just a couple of grainy pics with instructions to hook up as shown. I started with the turnbuckles since I knew they were definitely involved and I could locate those parts. Having never worked with turnbuckles, I was immediately confused because I had multiple packages of what appeared to be the same parts with different part numbers and different quantities of each?

I started scouring the usual web sites looking for clues, pictures or even directions. I ended up looking up the part numbers on Aircraft Spruce's web site and fortunately, they had a diagram showing the relationship of some of my parts. Finally after fiddling with the parts, it dawned on me that some were reverse threaded, this made it easy to get all the parts together... they only would go together one way. However, I did have two fork ends while there were five cable eyes? I figured out that the fork ends actually hook up to the rudder pedals. So, I ended up with seven completed turnbuckles. From this two for rudder pedals, two for flaps, two for down ailerons and one for up ailerons. The manual does say to screw the eyes into the barrel until no threads are showing, this is the mid point and allows 1" to 1.5" of adjustment in either direction which will be plenty.

So, I decided to start with the rudders. First I tied a string to the rudder pedal and ran it back to the rudder adding a little adjustment, marked and measured it. Then measured out and cut two lengths of cable to match. I swagged the thimble to the cable eye on the rudder pedal end and put the turnbuckle assembly together and bolted it to the rudder pedal. The directions suggested to fix the rudder pedal in a position 18" from the "control tower" where the sticks are located. I fixed the rudder pedals in place and ran the cable through all the cable guides in the fuselage back to the rudder.

The rudder had to be centered and braced so not to move. Then I had to drill a hole in the tabs on each side of the rudder to accommodate the AN3-5 bolt for the shackle. A thimble goes on the shackle and is swagged in place with the cable being drawn tight.

Repeat for the other side.

Tail Light Continued...

Yesterday, I got the fabric plates installed with the cut out for the wires. I Hysol'd the tail light housing in place on the fabric plates, clamped it and left it to cure. This morning, I noticed that there were some stress cracks because the part did not fit my rudder exactly (this is a Kitfox part I have modified to fit). This actually is ok because the cracks relieved the stress on the part.

So, I filled the joints with SuperFil and let that set over night. Then I began filing, sanding and shaping into the final form. I taped up the rudder and sprayed a couple of coats of primer on the unit. It's ready for cover and paint.

Pitch Servo Tray

I pulled the pitch servo tray for painting. Before I painted it I wanted to add a stiffener to it for good measure. The bottom of the tray has to span a distance from one attach point to another which allows minimal flex. I wanted to prohibit that flex so I added the stiffener. Not a big deal, just a piece of angle bracket material Hysol'd and riveted to the edge of the tray. Once fitted, I left it to cure before spraying primer.

Eventually, this part will be sprayed with a 2k gray epoxy paint that matches the gray powder coat on the fuselage. There are many parts to be painted like this and I will do them all at the same time.

Trim Servo Cover Continued...

I applied SuperFil to the cover and let it cure all day. I came back to it, sanded and shaped it til I was happy and hit it with a couple coats of primer then machine gray paint that I had laying around. I wet sanded between coats of paint. I finally hit it with a coat of white to make the final color pop when I finally paint the plane.

Kitfox Covering Continued...

Spent this morning working on the Kitfox covering. Terry was concerned about some wrinkles he couldn't remove from the side we covered on Tues. After viewing the side, we determined he was over aggressive with the heat gun and tiger striped the side where he was trying to shrink out wrinkles. If you over heat the fabric it will damage the finish, essentially changing the color slightly. Not a safety of flight issue, a cosmetic issue. So, Terry has to reconfigure his paint scheme to hide the striping. However, the side was tight and there were no wrinkles.

Before we rotated his fuselage, we laid out cut the vertical stab piece of fabric. Then we rotated his fuselage to layout the final side and the opposite side of the vertical stab. We got all of the remaining fabric pieces cut and marked for glue. We'll finish the covering later next week.

Tail Light Continued...

I started on the tail strobe today. Making it up as I go. I took a Kitfox housing and cut it down to make it fit the SuperSTOL Rudder.

There are several problems regarding how to mount the housing and run the wire? Do I mount the housing before covering or after? If before, the housing will create an issue when covering because of the irregular shape. If after, mounting the housing will be harder as will routing the wire.

After much deliberation, I decided to mount the housing before covering. Before mounting the housing, I wanted to design and fabricate some fabric plates to go around the housing. These plates will greatly help in attaching the fabric around the housing. So, I starting laying out and cutting some aluminum. I determined that I couldn't just have two plates, one on each side. I would need four plates, two on each side. This is necessary so the fabric will lay flush with the rudder assembly.

Once the four plates were cut out, I had to fit them to allow the wire to be routed and to clear the welds. Once I was happy with the fitment I Hysol'd them in place.

With cutout on bottom plates for wire pass through.