Tonight I final torqued the pushrod jam nuts, and then installed the first pushrod into the fuselage.
Before I final torqued the jam nuts, I made a simple measuring device to ensure I had the right dimensions on the pushrods. I installed a temporary bolt into a length of wood, and using this to pin down one end of the pushrod, measured the center of the hole at the other end. This seemed to work well, and after a few minor adjustments I torqued down the jam nuts and marked with torque seal.
Bolt holding one end of the pushrodMarking the length of the pushrod for measuringFinal torque applied to jam nuts on the rod end bearings.
Installing the first pushrod into the fuselage turned out to be harder than I imagined. It gets fed through from the bulkhead at the back of the baggage compartment, which is easy, but getting final torque on the nut was really hard due to the limited access. It took an hour just to get the one nut torqued correctly.
The troublesome bolt, final torquedFor context, the pushrod connects to the torque tube in the cockpit and extends aft to the area just behind the flap motor
Tonight I found the rest of the elevator control parts, drilled, cut, deburred and primed them all. One of the parts has an optional lightening hole, I drilled it out, but only to 1 inch diameter, as I don’t have a 1 1/4 inch step drill. I don’t think that matters, but will find out later!
I also located the elevator autopilot kit, and will install the motor at the same time as I install the rest of these parts.
Primed parts. I used some dowels to suspend the pushrods while painting. That worked well.
Tonight I finished assembling the elevator pushrods. This was a case of lightly sanding down the primer and installing the caps in the end of the tubes and riveting them together. This ended up being time consuming, but not very difficult. Once these get primed on the outside, they will be finished and ready to had the rod end bearings installed.
Messy desk, but everything I need to pop rivet these pushrodsOne end of one of the three pushrods
Tonight I started making up the elevator pushrods. There are three aluminum tubes that have caps installed, with threads for rod end bearings. I final drilled the holes in all three pushrods and primed the inside of the tubes.
The plans ship with a template, which I used to trace onto some thin trace paper. I’m glad I traced it, vs just cutting it out of the page in the plans, because I discovered the printing wasn’t to scale. The first template I made didn’t quite fit around, and when I checked the scale on the plans page I realized it was printed at about 95% true size.
Once I had adjusted for the error and made a new template I marked out the holes and drilled them using my pipe clamp.
Then with the end caps in place, I final drilled all the holes and deburred them. Then i primed the insides of the tubes and left them to dry overnight.
Pilot holes drilled in one end of one pushrodDrilling the holes. Lots of them. Clecos holding the end caps as I work around match-drilling the final size holesAnother shot of the ends being final drilled
Tonight I test fit the idler bars, and sanded down the flanges of the idler bracket to ensure clearance. These bars are responsible for the transition from one elevator pushrod to another, and must swing freely through the full range of motion. At first they were rubbing slightly on the bracket, but after some patient sanding with Emory cloth I was able to achieve the appropriate clearance. Hopefully it’s enough to still clear the bracket after I prime the parts.
The final step in the brake and rudder system is to hook up the cables to the pedals and then install the the cable guides. I counter sync the cable guides, and pop riveted them in place.
Clecos holding the rudder cable guides in place before rivetingGuides installed
With the rudder pedals installed, I moved onto the brake lines. I studied the Beringer documentation for a while, and then re-read the Aircraft Specialty documents. I started by routing the cables and doing up the fittings finger tight. I realized I would need to step drill the second lightening hole on the rudder bar support. It was a quick effort to step it up to 11/16ths to fit a 750-10 bushing.
Middle of the three holes has been enlarged to house the same snap bushing as the one next to itLines connected to brake reservoir and flange fitting. On the other side of the fitting, brake lines will route down the gear legs to the brake calipers on each wheelThe banjo fittings that attach to the pistons. A copper washer either side of the fitting creates the seal
With everything routed and looking good, I final torqued the lines, then plugged the two openings on the front of the firewall with plastic caps.
Brake lines installed. Just need to add a couple of zip ties to tidy up the cables
Tonight I installed the rudder pedals. They are held on each end using blocks of hard plastic, and with one block in the middle. I was able to get the bolts into position without too much difficulty. They have an adjustment, and can be moved into three positions depending the the length of the pilot’s legs. I set to the middle position for now.
Tonight was a busy night. My friend Simon came over to help me rivet the firewall flanges, and to torque up the nuts on the fuel line.
We were able to quickly and easily rivet the fittings on. I had to modify one of my rivet gun fittings to grind down one side, allowing it to fit squarely onto the head of the rivet without touching the fitting. Because the rivets were essentially glued in place, I numbered the rivets so we could just call out which rivet we were setting.
The brake line flanged fitting before rivetingFront of firewall brake flange fitting.The brake fitting after riveting. Note the numbering to identify rivets
Torquing the fuel line required Simon on the front of the firewall with a wrench holding the correct clocking while I cranked up the torque inside. With that done, I installed the flexible fuel line and torqued it also.
After torquing the fuel line nut
Next, I installed the NPT fittings into the brake fittings, including the T fitting connecting to the reservoir. I used Loctite 565. I torqued up these fittings, doing two full turns beyond the initial point of resistance. Getting the clocking right on the t fitting took two attempts.
NPT fitting installed
Then I moved onto the flap motor. This required a carefully drilled hole to hold some safety wire. The drilling wasn’t too hard, and the hole turned out exactly how I wanted.
With the hole drilled, I then installed the motor into the fuselage.
Then finally, I routed the rudder cables forward, and secured the polyethylene tubes in place using adel clamps. These protect the spar from the rudder cable, so they are carefully positioned to do so. Getting the nuts onto the bolts was challenging, but I found it possible using tape to hold the washer and nut, and then rotating the bolt until it caught.
Tonight I drilled the flap torque arms, then installed them into the fuselage.
The flap motor sits between the pilot and passenger, oriented almost vertically. The motor connects to a lever that rotates an arm that extends under the seats out to the wing root on each side.
The arms are match drilled to the center fitting using a template (same one used for the wings). I had to slowly step up the drill size because the steel was grabbing the drill bits.
Once the arms were drilled, it was disassemble and install into the fuselage. Some grease helped squeeze the arms through the plastic blocks and into position.
Drilling the arm using the template Installed arm, showing at the wing root where it connects to the flapCenter fitting to which the flap motor will connectLooking down into the cockpit, the flap motor will mount on the space to the left
