Fiberglass Wing Tips and Panel mod

 April 5 2021

I bonded blocks of soft foam onto the ends of the wing tips and then began to shape a simple tip which was pleasing enough to me.  I then covered the pink soft foam in packing tape as a release agent for the fiberglass.   The foam being so soft is great for carving but is delicate and requires care when touching it.  Sanding the surfaces of the upper and lower tip edges gave a good bonding surface.   I laid  up the upper and then the lower surfaces first because I knew that it was going to be difficult forming the compound curves around the tip.  This way I would have a firm surface to work the edges of the outer cloth onto the hardened upper and lower surfaces.  Because the outer three layers now cause a small step in the surface I will have to fill with filler.  The foam blocks were attached with two part auto body putty dabs placed randomly over the outer wing rib.  The tip came off the mold quite easily as the release tape worked excellent and the foam broke away from the auto body putty.  It was a bit of work to get them off though and I had to work tools between the fiberglass and the release tape before pounding on the surface to get the foam to break free.  The foam came out of the inside of the tip after removal.  They can be pried out or the whole foam plug can be dug out later if it is difficult.  One of mine came out very easy and the other needed persuading and a few chunks of foam broke out.

Then I fabricated L shaped flanges which will be the attach points by laying up four layers of glass along the edge of a piece of wood with packing tape on it.  The flanges were trimmed to 3/4" by 3/4" and marked into one inch sections where I installed a nut plate onto each one inch section.  These flanges were bonded onto the outer face of the outer  rib, 7 on top and 7 along the bottom using structural adhesive.

The tips were attached and holes drilled at each nut plate location.  The new tips overlap the aileron and so a piece had to be trimmed off to allow the aileron to move.  Once trimmed I made a rib to fit inside the tip at the aft end to add rigidity and to close off airflow into the open aft end of the wing tip.  This was bonded on with a thin layer of epoxy/flox.

The instrument panel central radio section was modified for a Dynon radio head and the far right section modified to allow the ELT remote switch and 3 pull off fuses for the Flaps, Auto Pilot and Avionics.  Panel sections were then painted in semigloss black.

Engine Silicone Baffling and Auto Pilot Servo mounting

 March 7 2021

A large part of my time this month was spent fabricating the Silicone seal baffle around the top of the engine.  I set up a system of sliding wooden pieces to identify the height from metal baffle to inside surface of the cowling.  Then I was able to determine the width of silicone to use.  The standard 3 inch stuff worked out to fit well.  I decided I wanted all silicone to be removable and so installed on #6 nuts and bolts with a aluminum back plate.  This also allowed me to use pieces with fewer separations as I did not have to account for each separation in the aluminum baffling material below the silicone.

I began building a two brackets for the autopilot servos, the roll unit going under the passenger seat and the pitch servo insider the center console.  A lot of test fitting was required and the aileron and elevator push pull tubes were disconnected and reconnected many times to find the right fit.

The position of the A-pilot units ended up to be too close to the ADAHRS unit with a magnetometer inside it so I made a new bracket for the ADAHRS and positioned it in the rear just behind the baggage compartment.

Air Intake to Air Filter Box

 February 24 2021

I got into work on calculating how I could get the air intake on the front of the lower cowling to mate with the intake opening of the Air Filter Box.  Numerous friends had mentioned it was a tricky bit of maneuvering to get the lower cowling on and mate the air intake.  A friend with a RV mentioned I could cut off the front of the cowling intake and make it removable.  This sounded perfect, so I did some internet research and found some guidance.  I decided to make the front intake removable with an attached tube entering the Filter box.

Below after the foam was shaped the difficult part was getting the 3 layers of glass cloth lined on the inside of the opening.

Glassing of tube completed, time to cut off the intake after finding a pleasing cut line.

I trimmed the new fiberglass tube to about 4 inches long.

Using tongue depressors as spacers I bonded the intake back on using auto body putty.  Then working on the inside of the lower cowling I laid up 3 layers of glass for a flange.  The gap where the cut line was will later be filled using micro.

After trimming, nut plates were mounted in the newly formed flange.  I should have made the upper nut plates at 10 oclock and 2 oclock as it was hard to get the rivet squeezer placed at the 12 position.

Hand carved a piece of foam until it was a the proper shape of air intake and of the Filter box.  Covered the foam with packing tape and then temp. bonded into the air intake unit.

Very happy with the finished product, it makes a beautiful fit to the filter box entry mounted on the engine.

Oil Filler Access Door

 January 8 2021

The oil filler and dipstick access was started by making a Splash coat of  3 layers of carbon fiber and then laying that onto the top surface of the engine cowling.  I identified the location and size of the door, marked it on the cowling with a sharpie and taped over area with packing tape.  This was left to harden for a couple of weeks while I did other jobs.  I spoke with a friend who builds Vans RV's on the field and he suggested I build a hidden hinge style for better esthetics.  I was happy to go this route and had a great example in one of his planes to model mine upon.  The splash coat is to form a new oil door from that is a perfect match to the curvature of that location of the cowl.  I removed the splash coat and then carefully cut out the shape of oil door I wanted.  Then I cut and trimmed the Carbon splash coat to exactly fit the door opening I just made.  I taped the inside of the oil door in packing tape then taped the new door into place on the outer surface of cowling.  I then made up fiberglass strips for flanges and applied to the sanded inside surface of cowling, these will support the oil door.  Afterwards trimmed down the flanges and installed the 2 Milspec quarter turn fasteners which will it closed.  I then bent up the aluminum curved hinge adapter out of .062 thick aluminum.  Trimming off the excess aluminum (right hand edge in photos) to get a good fit, finally drilling and cleco in place.  I am only riveting the outer ends of the piano hinge and other holes all have a dab of structural adhesive.  The hinge onto the adapter will have 5 rivets.

Canopy Latch Torque Tube

 December 2 2020

I had bought a canopy latching torque tube from Vans as they use on the RV6 tip up canopy.  Some parts I wouldn't be able to use but the method of latching was sound.  This torque tube goes just under the seat back and across the fuselage hanging in Nylon blocks at each outer end.  The nylon blocks are the ones that came in the kit from Vans and are anchored to the seat back.  I had my welder weld on a center arm that has the yellow release knob attached to it with a secondary short metal arm.  The knob comes up and forward going into the aft edge of the seat back about 1.5 inches.  Only a narrow .25" slot was needed to be cut into the seat back upper horizontal section to allow the knob to come forward.  It will have a locking tab installed later as a safety lock for in flight.  This was a lot of tricky work and took some time to get all configured.  Another detailed drawing of my dimensions was recorded for my future reference.

The outer end of the port tube I had a hex socket welded in place and so my entry key is just a hex key adapted with a 3 inch handle welded onto the short end  of the hex key.  Remove the hex key and there is only a .25" round hole exposed.  Hey loose a key, just get another from the hardware store.

Photo later

The upper canopy will have the mating receivers installed that were part of the Vans canopy latch package.  these will be done sometime later.

Photo later

Pitot and Static Connections

 November 16 2020

The pitot static vents have been installed on the aft fuselage sides.  As is done on Vans aircraft I have just used a Aluminum pop rivet outer shell and it is just the proper size to allow the plastic tubing to be friction fit on.  I believe the tubing is .17 ID and .25 OD and I am using just a common hardware store clear tubing.  My Pitot airspeed tube has be fabricated to mate to the chrome extension and connected to the plastic pitot tubing in the wing.

Flaps and Flap Motor Assembly

 November 5 2020

Assembly of the flaps and the flap drive motor onto the fuselage are beginning,  Most was previously fabricated but now needed to be installed and all connected up. The slotted flaps with a curved leading edge allow air to flow over the flaps as they are deployed.  These are hinged on the bottom of the wing using external hinge hangars.  As flaps are dropped back there is a air opening that will allow some under wing air to flow over the tops of the flap surface.  Drive motor was installed which hangs on the back side of the passenger seat and drives a torque tube for the flaps.  Each end of the torque tube has a forked fitting to mate with rod end bearings on the flaps.  The flap motor was installed with the electronic flap positioning unit sold from Vans.  It took quite a bit of setting up but it now works setting the flaps to 6 degrees, 12 degrees and 33 degrees.    

The rod end bearings and fork go above my wing root fairing about 1 inch and so a rectangular hole had to be cut open.  This rectangle will end up with a blister of fiberglass over it to hide this opening which is in the No Step zone of the wing.

Below is the flap motor and flap torque tube showing below it.  The electrical wires are to the motor and the flap positioning unit, which presets the flap extension for 6, 12 and 33 degrees.  At the bottom of the drive motor is a block of wood bonded to the side of the tunnel, this is a safety to stop the motor/drive arm from being able to ever go over center.  Were this able to happen the flap mechanism would  lock up in the down position.  The flap switch on the panel allows a tap of the switch for each down position and moving the switch to up retracts the flaps fully.