Header Tank Drain

The hole for the header fuel tank fuel drain stop cock was located and drilled.  To get a nice tight fit, several drill sizes were used.  The hole was then deburred.  The stop cock and coupler were provided with the kit.  A fuel safe thread lubricant and sealant was placed on the threads and tightened down for a nice fit.  Hours: 1

Hole Drilled for Fuel Drain

Stop Cock installed

Trim and Misc

Been a while since our last blog posting.  Michael's been working on the 3D printed trim servo cover.  Went through a lot of iterations to come up with the finally design.  Another issue was having to order more parts from Aircraft Spruce to mount the trim tab fabric mount plate.  We had plenty of CCC-42 and CCC-46 pulled rivets, but needed CCC-44's.  A few days later a packet shows up with the required rivets and we permanently installed the plate.  The fabric plate has four nutplates for mounting the servo, and two additional nutplates for mounting the standoffs and cover.

3D printing a trim servo cover

Trim fabric plate installed

Trim Servo in place

Trim cover installed

Ed has been working on the vent line in the right main fuel tank.  We ordered a fuel fitting from Sonex that will allow us to mount the vent in the tank.  Due to limited space, Ed needed to make a special wrench for installation.   

Ed cutting tool  from a steel plate

Below is a picture of the finished wrench next to the Sonex fuel/vent line fitting.  The wrench had to be small and thin to fit in a tight area next to the tank.  A template was made out of paper first, then this was traced onto a steel plate, and then cut out to make the finished wrench.

Special wrench will allow us to install the Sonex fitting to the tank

Hours: 5.0

Magnetometer and Trim Servo

The magnetometer mount was finally installed in the right wing because the aluminum rivets we were waiting on finally arrived.

Also, Michael has been working on 3d printing a plastic fairing for the trim servo to improve the airflow around it.  After several revisions, we are close to settling on one that fits nicely around the servo, and (should) mount easily with just a few screws.  One issue that we had, though, was that the servo mounting plate we previously installed for the servo and the fairing was a little too small, so Michael fabricated a new plate sized just right.  However, making it larger led to another problem because we really needed some some new mounting tabs on the elevator in a slightly different location.  So to resolve this, I fired up the TIG machine and (after cleaning and prepping the area) welded a couple of small tabs so that we could securely install the new mounting plate.  This area of bare metal was then primed and painted.  Hours: 8

Two additional mounting tabs added to elevator

Primed and painted

Magnetometer, Aileron cables, Trim planning

We had a little bit of a snafu with the mount we built for the magnetometer.  When we went to install it in the right wing, we found that we didn't have enough adjustment available to get it level within 3 degrees (per instructions for the magnetometer).  We were close, but no cigar.  One side of the magnetometer bracket was just a little short.  Unfortunately, it's harder to add aluminum than remove it.  To fix this, we cut off one side of the mount, and riveted on another piece that was a little longer and allowed us to get put the magnetometer in the right position.  We also found that we can't install the mount quite yet because we needed some aluminum rivets that were a little longer.  Those are now on order and should arrive in a couple days.

Magnetometer mount with new L-bracket riveted on

We also ran the cables for the ailerons and flaps in the right wing (we had already done this in the left wing).  Next, we planned out how we we are going to run the wires for the trim servo within the elevator.  Michael is also experimenting (with his 3d printer), with fabrication of a plastic fairing for the trim servo.

Hours 4.0

Header Tank Vent and Wiring Work

We are adding a vent for the header tank in the right main fuel tank.  This will require us to drill a hole in the tank at the high point of the tank and install a fuel fitting/bung.  In order to provide room for this addition, a small section of the root rib was trimmed back with a Dremel sanding wheel.  

The wiring for the ELT and Trim Servo were neatly routed and cable tied from the rear of the fuselage to the front.  High temperature (280F) industrial cables ties were used.  Also, self-sealing silicone tape was added at each attach point to keep the cable ties from abrading the metal members.

All the cable ties around the ELT were replaced with with the Hi-Temp cable ties.  And finally the ELT mounting tray was riveted to the fuselage with CCP-42 rivets.  

Also, the excess material on the mounting tabs of the header tanks was trimmed off.  Hours: 2

Lots of Miscellaneous Work

Lots of small tasks needing to get done.  The cable connecting the ELT to the "yet to be determined" GPS source needed a connector on the ELT end of the cable installed.  The ELT manual calls for a 3 wire shielded cable from Aircraft Spruce.  The connector was supplied with the ACK ELT and it was soldered on. The ELT instructions call for adding RTV sealant in the connector to keep water out.  The cable was temporarily installed.  New industrial grade high temperature cable ties were ordered for the final installation.  To stabilize the connector at the ELT, a WDG-09 P-clamp was installed.  Also in the same area, two small #30 holes were drilled for a cable tie to secure the coax cable.

GPS cable installed and Coax Cable Secured

The rear windshield bracket was primed and painted a few days ago.  Now that the paint has fully cured, it was cleco'd in place.

Rear windshield bracket primed, painted and Cleco's in Place

Finally, there are areas on the root ribs and butt ribs that needed a coating of the Superflite epoxy varnish.  The epoxy varnish was mixed with the catalyst and reducer in a 1:1:1 ratio.  Hours: 3

Left Wing Cuff Filler and ELT

We've been working on the left leading edge wing cuff and ELT for quite a few days.

On the leading edge wing cuff, we've been adding lightweight epoxy filler to smooth the transition between the cuff and the front spar tube.  Due to the high heat, the filler is curing quite fast, so we are having to work in small batches or we waste a lot of filler.  Then, once we let it cure, it is sanded smooth.  There were also some areas we had left without filler until the cuff was installed.  these areas were the transition between the ribs and the front spar.  Filler was added in these areas as well.

Filler Work Finally Completed

 The ELT plate had been installed quite a while ago.  We finally ordered an ACK 406 MHz ELT (model E-04)  and started the install.  There aren't many options in the ELT installation location.  Using the real parts, the base unit and antenna holes were located and drilled.  After installing the antenna and base unit on the ELT plate, we noticed that there was not enough room to connect a BNC cable to the antenna and not have it interfere with the bottom fabric.  So with a little head scratching and a lot of "what ifs", Ed and I came to the conclusion that a new ELT plate needed to be fabricated with a slight modification in the antenna mounting area.

It was no surprise, but we had to order the correct aluminum plate (0.040" thick) from Aircraft Spruce.  We also had to order the wiring needed to complete the ELT installation, as well as the mounting screws and nuts.

Once the plate arrived, a few days later, a new plate with modification was fabricated and the new bend was made on the metal brake. The old plate was used to locate the mounting holes for the ELT base unit and the antenna hole was located to place the antenna were we needed it.  Now there's plenty of room for the BNC connection.

On last  piece.  We wanted to add something to keep the antenna from bounding around, possibly hitting the fabric and or controls.  After taking measurements and coming up with a quick hand drawn part, it was created in a 3d Design program and printed on a 3D Printer.  The part was put in place and epoxy was added to secure the part.  Finally a shorter Coax cable was built, as the one provided with the ELT was extremely too long.

Total Hours: 8

Old and New ELT Plates

New ELT Antenna with plenty of room

3D Printed Part to control Antenna location

ELT Installed with new Coax