Category: Cozy Experimental Aircraft Project

Left Wing & Winglet

Removed the peel play at the winglet to wing interface and removed the bondo that was securing a brace during winglet installation.

Seven new AN525-832R8 screws were installed in the aileron hinges to replace the temporary screws used during aileron construction and setup.

Four solid AN470 AD4-10 rivets were installed in the aileron pushrod rodend assembly using the rivet squeezing tool.

Epoxy was injected into an air bubble near the root of the leading edge as well as into a bubble near the top inboard wing/spar attachment point. Workshop temperature was 23 deg C with 55% humidity.

Inboard trailing edge corner repair (top side) with two layers of bid cloth.

One 6″ hinge and two 4″ hinges for the left rudder attachment.

Sanded the rudder and the winglet at the top of the rudder opening and at the hinge locations. Marked the locations for the rivets and screws on all 3 hinges. Drilled holes in the hinges on the side that attaches to the winglet.

Nutplates were secured to the winglet side of the hinges with solid rivets. The three left rudder hinges were aligned with a straight piece of board and held in place on the winglet. A flash light was used to identify where the holes needed to be drilled in the winglet to align with the screw holes/nutplates on the hinges. The holes were drilled and the fasteners inserted.

Removed all three hinges and drilled holes for the rivets that will attach the hinges to the rudder, Re-installed the hinges on the winglet and clamped the rudder in place.

Drilled holes in the rudder to align with the holes in the hinges starting with the centre hinge, then the top hinge, then the bottom hinge. Clecos were used to secure the rudder on the hinge.

The rudder can freely move outward by 4.5″ at the trailing edge.

I removed the rudder and hinges from the left winglet. Removed all clecos and the hinges from the rudder. I covered the centre and winglet side of the hinges with tape and mixed up a small batch of flox.

I applied a light layer of flox onto the inside of the rudder on the outboard wall where each hinge sits. I secured each hinge in place with pop rivets. Five rivets on the top and middle hinges and seven rivets on the bottom hinge.

Installed spring on the winglet and re-installed the rudder. Located the position on the rudder for installing a hook to align with the spring. Drilled a 1/4 inch hole in the rudder. Made a hook out of piano wire. Mixed a small batch of flox to pot the hook in place.

The wing was turned over on the table to inspect and access the bottom side of the wing and winglet. The left winglet was damaged during ground transportation from Alberta to Ontario.

The damaged glass was cut out with a dremel tool and the area vacuumed. A piece of foam was cut and rougly shaped to be used for the repair.

Workshop temperature 23 deg C and humidity 62%.

Mixed a small batch of epoxy and poured a bit into other cups to make flox and micro.

Applied micro to the bottom of the damaged winglet to fill all void areas and micro’d foam in place. The foam was taped down while it cures.

Flox was applied to the inner trailing edge of the left wing on the bottom side ontop of the 2-ply bid repair already completed on the top side. The flox was covered with 2-ply bid, peel ply, and held flat and in place with a shim and clamps while it cures.

Trimmed and sanded the trailing edge repair to shape.

On the left winglet repair, extra foam was cut away then the foam was sanded to shape.

Cut 2-ply of UND cloth to repair the bottom of the left winglet and a small 1-ply of BID cloth to repair a spot on the trailing edge (TE).

Workshop temperature was 25degC and humidity 60%.

A small batch of epoxy, flox, and micro was mixed.

Micro was applied to the exposed foam on the winglet then covered with 2-ply of UND cloth and wet out with epoxy.

Flox was added to the low areas on the left wing trailing edge and one ply of BID was placed over the area.

Peel ply was added to both repairs.

Removed the peel ply from the winglet and wing TE repairs and sanded as needed.

Flipped the wing right side up again on the work table and installed the left rudder in the winglet and attached the centering spring.

Centre Section Spar

The Cozy MKIV centre section spar joins the wings to the fuselage. The center section spar is the heart of the wing structure.  The top of the spar is flat and the spar sweeps aft and the bottom has positive dihedral so that the fuel runs inboard while in level flight.

We did a trial fit of the spar with the fuselage and need to sand a few rough edges on the fuselage to get a better fit.

After a bit of sanding the spar rough fit into the fuselage.

The spar was moved back to the worktable and all outside surfaces were sanded.

Removed a small amount of foam from the outboard holes on the bottom of the spar. Mixed a small batch of dry micro and applied it to both holes to protect the foam.

Used the dremel tool to make a small flox corner around both outboard bulkheads CS5 & CS8.

Workshop temperature was 24 deg C and humidity 28%.

A batch of epoxy was mixed up and used to make up some micro as well as a small cup of flox.

Epoxy was brushed onto the existing glass edges of the outboard bulkheads then micro was applied to both bulkheads.

Next, the edges were filled with flox to make flox corners.

One layer of BID cloth was placed on each outboard bulkhead at 45 deg orientation and wetted out with epoxy. Lastly, peel ply was added to both layups.

Removed the peel ply from both outboard bulkheads.

Trimmed the glass edges and sanded the edges to be flush with the spar.

Sanded the inside centre section and vacuumed the inside of the spar.

Canard Wing

Here is a video of the canard fit and functional test.

During transit from Alberta to Ontario the canard wing received some minor damage to the right elevator trailing edge and the left tip fairing.

Loose and damaged pieces were cut away from the right elevator trailing edge where the damage occurred. 1-ply BID cloth was cut to size and taped tightly to the bottom of the damaged area.

A mixture of epoxy consisting of 38g resin and 14g hardner was mixed and some of it was used to make a small batch of dry micro. Workshop temperature was 23 deg C and humidity 53%.

The damaged area was filled with dry micro and the BID cloth was then tightly taped to the top surface. The cloth was wet out with epoxy about 1″ back from the damaged area on all sides.

A number of low areas was noticed along the trailing edge of both elevators and so dry micro was added to fill any low areas.

The lower area of the damaged fairing was repaired and held in place with wetted peel ply taped tightly to hold the repaired area in place while it cures. The upper area will be repaired once the lower area cures.

Trimmed and sanded the right elevator repair and sanded other trailing edge rough spots.

More sanding of rough spots along the top side of the canard. Began the left tip repair with a small BID patch on the bottom of the tip over top of a crack. Dry Micro was mixed and low areas were filled in along the canard.

The left tip fairing was filled with micro and clamped in position. Excess micro was wiped away from the sides as the clamps were applied.

The left fairing was sanded on both sides. Dry micro was added to fill some valleys on the bottom side of the fairing. One ply of BID cloth was applied to the back side of the fairing to replace material that is missing.

The right outboard mass balance was detached from the canard when it arrived from Edmonton. I placed wax paper under the existing UNI strap and mixed a small batch of epoxy and dry micro. I added dry micro to replace any missing foam between the foam piece on the mass balance and the foam remaining on the right elevator.

I used a 1″ brush to apply epoxy to the UNI strap and to its interfacing locations on the mass balance and elevator. I used a clamp to hold the mass balance and UNI strap in position during cure. A single layer of BID cloth was applied over the UNI on the elevator to hold the UNI strap in place.

Tightened the two inboard mass balance weights.

Added one layer of UNI cloth to reinforce the right outboard mass balance.

Sanded the bottom side of the canard and added dry micro to smooth over any low points.

Continued sanding the bottom side of the canard, vacuumed the dust and then turned the canard top side up.

Sanded and vacuumed the area to be repaired on the top side of the left fairing.

Applied flox to the edges of the top left fairing and applied a layer of BID cloth and covered it with peel ply.

Removed the peel ply from the left fairing repair.

Trimmed and sanded the left fairing to shape.

Sanded the top side of the canard, vacuumed the dust, and applied dry micro to any low spots on the top side.

Sanded the top side of the canard.

Tested the fit and function of the canard on the fuselage. Verified the elevator balance was sufficient.

https://www.youtube.com/watch?v=xTLwKq0Bx8E

Canopy Hinges

The locations for the canopy hinges were marked on the longeron.

Two pieces of MS20001-P6 hinges were cut to10″ lengths.

The hinge halves were separated.

Sanded the bonding surfaces of the hinges and the longeron. 220 grit on the hinges and 36 grit on the longeron.

Tape was applied to the hinges to keep the epoxy out of the hinges.

With the workshop temperature at 24 deg C, a small batch of flox was mixed using 15g resin and 6g hardner.

Flox was applied to the longerons and the hinges were positioned on the longerons and clamped in place such that both hinges are in the same plane.

Drilled #12 holes through the canopy hinges and longeron and countersink.

Installed machine screws, washers, and nuts to secure the two canopy hinges in place.

Cozy Fuselage

1/4” holes drilled and sanded for front and back seat centre safety harness anchor points.

Opened up the 1/4” holes for the landing gear in the forward and aft landing gear bulkheads.

Opened up the 1″ holes in the landing gear bulkheads for the torque tubes.

1” holes opened up in the front seatback – two for the torque tubes and one for the canopy latch mechanism.

1″ holes in the front seatback