Cozy Construction Chapters.
Chapter 20 - Winglets & Rudders
Started 08/29/2010 finished 01/29/2011 Hours worked this chapter :128
Purchased the pre-cut foam when I got the wing cores.
Macro the two rudder foam cores using the foam block that the where cut from to hold them strait with core line as the indicating mark.Nails used to hold in place till cured.Glassing the rudder bottoms using the foam blocks as jigs to hold them off the workbench clear for glassing.Glass trimmed ready for side two.
More or the same on the other side.The support foam is cut away before glassing begins. Fish tail has been cut and sanding complete.
Glassed with peel-n-ply.
This is the layout of the antennas.
Lay out of rudder tip foam before glassing you add 1" foam, the shaping of the tip from the polyurethane foam is easer.
Macro with sand bag weights till cure
Sand sides to match rudder shape. The tan foam is much easer to shape into a pleasing rudder tip.
In these picture you see the two rudders with the antennas one with the co-ax cable and the other just the copper foil tape.
Rudder antennas one in each rudder. I used tooth picks to hold the co-ax down.Glassing the rudders with bid re-enforcement layup. To hold the rudders in place I used duck tap and nails.
Once again I used the aluminum angle and small clamps to make sure the trailing edge is true and strait.
The leading edge of the right rudder had some air bubbles I missed, so I drilled small holes and pumped in macro to fill the air bubbles.
The right rudder foam did not cut clean on the first side glass which I think left larger voids than normal and I did not put thick macro on to fill them.
Cutting the wing tip, marking the foam that will be removed to allow the glass re-enforcement layup. Using the rudder to create the cut line. Made the depth line with a protractor, with the curves it was a fast and easy way to lay out the guide lines. You might notice the cut foam peaces on the wing, the rough length of each wing meant that the amount of wing tip removed was not the same. The right wing was a little longer than the left, but once all measurement and cuts made they are now identical. So don't worry as I fist did when I discovered the difference.
Once all is true and measurements as correct I used 5 minutes to hold the rudders in place.
Blocks of foam and nail to prop up the rudder till glassing and support bracing is in place
In this shot you can see the cable and how the rudder is just lipped on the wing with the 5 minutes holding strong.Right wing shown here, all the lines are used to check the depth of the removed foam in the next few steps of the re-enforcement glass lay-up.
In this shot you can see the 5 minute holding the rudder and wing together. Left wing here.
Just enough room above the rudder in my garage.
Hot glued support bracing used to make sure no movement.
Scrap foam used to hold the rudder high enough off the floor.
Foam marked for removal, internal glass layup. I used a 1/8" dia. 2 1/2" long dremel rasp to clear the foam and macro down to glass.
Glass with flox fills the opening with foam wedges about 1" X 1". The foam is pushed in that displaces the extra flox leaving no air gaps. In the left hand corner you can see the radio cable going into the conduit near the wing tip. I used a 1/4" dia. 24" long drill bit.
Cleaned out the foam pocket for the hidden bell crank. The pin locates the point of rotation the bell crank mounting area can not go past this mark.
Here you see the bell crank in place glass and floxed foam filler block. The wood block keeps the rudder conduit off of the crank till cure.
Here's the block of foam on top of the inside glass with macro filling and air spaces.
The end of the rudder cable conduit is just visible. The green painters tap is there to make an easy clean up once all the macro has oozed out of the joints.
Right side same as the left above
Right side foam contoured and hidden bell crank waiting for cure.
Here you can see the pocket for the hidden bell crank movement.
Completed foam contoured
It took a long time and a lot of web searching to find out how this foam should look. The multi dimensional shapes made it a real mind bender.
In this shot you can see the brown packing tape covering the filler foam for the bell crank pocket. The filler foam is not glued in because it is dough out later creating the void area for the crank.
This is after glassing the reinforcement from bottom wing to outer rudder. The brown packing take makes is easer to clean out the foam later on.
A little bigger shot of the glass work, it was fun to see how the layer after layer of glass changed the wing and rudder making them one.
Right same as left
Mounting the bottom rubber half using an aluminum angle to keep the trailing edges in line.
Two 5 lbs sand bags holding down the rudder bottom till cure.
In this shot you can see some tape hold the leading edge from moving out of alingment.
This was a very interesting lay up giving the strength to the rudder and wing connection to the point I think it would withstand a tremendous load amazing construction.
Each play of Bid is an inch smaller as you can see in the tick marks show the edge of each ply. It just so cool...
Left wing rudder same as right.
The second time around I get better and didn't need the tick marks.
Rudder control surface cut free and set in foam blocks getting the internal glass layup. Did the rudder internal at the same time.
Rib glassed waiting for cure and knif trim
Hinges in place, aliment using aluminum angle as seen on other hinge mounts.
Glass rig on rudder.
In this shot you can see the spring and hidden bell crank pockets.
Hot glued the sticks to hold the hinge halves up for mating with the rudder control surface.
The rudder side of the hinge will be removable as the control side will be pop riveted in place and floxed.
With the rudder control surface aligned to locate the rivet holes I shined a light on the back side of the rudder. Then using a drill made the holes in the control surface.
This site was last updated 11/16/11