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.
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 āZā 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.
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.
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.
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.
Angles for Drill Centring
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.
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″.
Rear Spar Carry Through Channel
Hole in Rear Spar Carry Though Channel from Cockpit
Enlarged Hole in Rear Spar Carry Through
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 3/16ā 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.
<p><b>Two days in a row!</b></p> <p>Today I began to look at the elevator. I started by digging out the box containing my formed metal and locating the root ribs. I checked the overlap on the front for the skins to be sure that the overlap was sufficient to allow for the correct drilling and edge distances. They both looked good.</p> <p>After looking at all of the ribs I had previously made I discovered that the root ribs were made from 0.025 material instead of 0.032. I proceeded to make new root ribs. I had the original templates so it was fairly easy. I just traced out the ribs, drilled the relief holes, cut out the ribs, and cleaned up the edges using a file, sandpaper and scotchbrite. Next, I marked the bend lines and formed the ribs.</p> <p>The next time out I’ll need to start trimming the skins.</p>
Today I finished forming the last of the ribs required for the elevator, ailerons, flaps and rudder. Here they are all layed out on the bench. The only thing remaining is the small joggle in the end ribs for the fiberglass tail tips.
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