Rudder Spring Holes

Today I continued with the removal of the rudder pedals in order to provide access for the drilling of the holes for the rudder pedal springs. I started by removing the bolts the secured the rudder cables to the rudder pedal connecting link. After removing the pedals I cleaned up the cockpit floor. I pulled the fuel line up against the fire wall and then proceeded to remove the fuel tank. 

Removing the fuel tank was a bit of a puzzle. I had to remove the fuel outlet in order to have clearance under the instrument panel crossmember and over the spar carry through tunnel. After a bit of fiddling it came out.

Next I worked to get the rudder spring holes marked. This was a bit challenging but easier now that the fuel tank was removed. With the holes marked I needed to figure out how to drill them. After trying to fit in my right angle drill and finding it was too large I started looking for smaller right angle drills. This seemed like an expensive idea so as I was looking through my tool box I came across my 12 inch long 18 inch drill bit. This was the solution.

I drilled the holes and while they were not exactly in the marked location they are both further from the edge of the angle which is actually better from a pull out point of view. I may have a bit of trouble getting the spring in but I think I can live with this.

Rudder Spring Holes

I discovered that I did not drill the holes for the rudder pedal springs. I spent some time figuring out where the holes need to be drilled but with the fuel tank installed this location is very difficult to get too. I need to remove the fuel tank.

Before removing the fuel tank I installed the seat pan and removed the control stick. This was to provide me a place to work from.

With the seat pan installed I removed the fasteners from the fuel tank straps. Next I tried to drop the tank down below the stops holding it in place. I forgot about the fuel cap and it prevented the tank from moving. After removing the fuel cap I was able to pull the tank forward but I could not tip it down below lower instrument panel cross member. So, I put the tank back in place.

I’ll need to remove the rudder pedals to lower the fuel tank further. This will be my next step

Brake Installation

Today I continued working on the brakes. I started by up drilling the 5/16 inch holes in the brackets for the master cylinder and temporarily mounted the cylinder so I could drill the hole in the floor for the inboard bracket. Next I drilled the pilot holes for the rivets in the floor for the inboard bracket. I trimmed the plastic film on the floor from around the mounting points in preparation for riveting. Once the floor was prepared I riveted the inboard bracket into place. With the bracket mounted I cleco’d the inboard bracket in place.

Elevator Pushrod Installation

I finished up most of the work on the elevator push rod today. I completed the drilling of the filler plate for the forward vertical support of the push rod. I riveted in the nut plates and then installed the support and the filler plate. Next I completed the pushrod installation by joining the two section of the pushrod and installing the bolts at the pivot points. I torqued the pivot bolts and inserted the cotter pins.


Elevator Trim Control

I removed the music wire from the housing so that I could work on straightening it. I used a pair of vice grip seamer plyers to grab the wire and  then my fingers and thumb to bend the wire against is current bend. This works to increase the radius of the wire to about 24 inches. I worked the ends of the wire a bit more to try and get straight sections at the end.

Trim Control Cable before Straightening

Next I located the trim tab for the elevator in order to check the fit to the trim control wire (music wire). The trim tab does not have the hole in it for the control wire so I located the drawing for the tab (SNX-T07). The drawing calls up a 5/64 inch diameter hole for the control wire. I drilled the hole in the trim tab.

Drilling Hole in Trim Tab for Control Cable

I installed the trim tab on the elevator and proceeded to make the “Z” bend in the music wire to connect the music wire to the trim tab. After connecting the trim tab I shortened the music wire in the cabin at the trim tab control lever. Then I secured the music wire to the trim control.

Flight Controls

Today I spent some time working on the flight controls. I had previously order some 24 gauge music wire and today I installed it in the cable housing. The cable housing was made from bicycle cable housing used for brake cables. This is very similar to the housing called up but actually has a teflon liner to provide smooth movement. The music wire was ordered online from I purchased a wire cutter for the music wire from my local Princess Auto store. The music wire had a curvature to it that was about 12 inches in diameter. This worried me a bit but after inserting it into the already installed housing there did not seem to be a problem.

Forward Elevator Push Rod Support Channel

I installed the plastic pushing in the aft push rod support channel and then moved on to the forward support channel.

The slot I had previously cut in the channel was not wide enough for the flange on the plastic bushing so I enlarged the slot width and opened up the radii at the ends of the slot. Next, I cut a piece of channel for the plastic bushing and then drilled and sanded a hole in it for the bushing. Finally, I re-fit the push rod for the elevator and temporarily secured the bushing support channel to check the fit.

Elevator Push Rod Support Channels

I noticed while fitting the elevator push rod that it would be impossible to remove the push rod once the support channels were riveted in place. While removing it might be an unlikely requirement I just felt that it should be removable. After giving it some thought I realized that it might be possible to remove and install if I changed the front most vertical support to include a slot for installation purposes. This would facilitate later removal. The slot could be covered over with a single hole in a second piece of channel installed with removable fasteners from the back side. I thought about installing the entire channel with removable fasteners but these could be difficult to reach and the channel was already drilled for rivets.

I removed the channel and then installed the push rod. Next I marked the channel to the height of the slot. With the channel removed I drilled a series of holes in it and then cut out the slot. I filed and sanded the slot and the tested it out. It seemed to work well. Next I will need to make the removable piece with the single hole in it.

Elevator Push Rod

I removed the push Rod and marked it for drilling. I had to go back to the C03 drawing for the location of the holes. I marked the holes in C03-05 half and drilled them using my drill press. I setup a couple of 1×1 angles to assist with the alignment of the tube. After drilling the -05 half I inserted an aligned the -06 half. I then drilled half of one hole in the -06 half of the push rod.

The next thing I did was to reinstall the push Rod and use a cleco to through the single hole through both parts to verify the correct alignment. It turned out that I was off by about 1/8″. I removed the push rood and drilled a second hol in the -06 half. This time I was able to get full movement of the elevator. The control triangle was still very tight to the rivets on the spar tunnel.I decided that I could flatten some of these rivets a bit using my bucking block inside the tunnel and a hammer on the end of the rivets that were protruding.

Elevator Push Rod

Today I worked on the installation of the elevator push rod. I started by opening up the hole in the in the rear spar carry through channel. This was to allow more adjustability in the push rod. I was finding the with the stick full aft the push rod bellcrank would contact the channel. I opened the bottom of hole by about 3/16″.

Next I installed the push rode and tried to find a position that left a bit of clearance at each end of the stick movement fore and aft. I applied masking tape to the push rod and marked a position that was 3/4″from the overlapping point of the two parts of the push rod. Next I marked an alignment line on the top on bottom. This will allow me to line up the two parts outside of the fuselage when I drill the two holes through them to connect the two pieces.

I then found the remaining channels for the fuselage so that I could mark them for the push rod hole. When I got out the channels I discovered that I had previously put the holes in them.

I clecoed the channels in place in the fuselage and reinstalled the elevator push rod. The hole in the rear most channels seemed okay but the hole in the front channel appears to be too high. I think I will see if I can make a new front channel with the hole about 3/16” lower.

The next step will be to remove the push rod and drill the three holes required for the AN3 bolts to secure the to pieces together.