Fiberglass Work Days

Time: 10 Hours

Since I’m at the stage to remove the wings from the fuselage I decided to tackle all of the fiberglass work that I can.  The rest of the aluminum work on the wings has to be finished after the wings are off and it’s easier to work on the fiberglass finish work now. To add some strength to the bottom of the wing tips I put just one foam rod in and fiberglassed it in like I did the tops. 

I’m really impressed with just how much rigidity these add and still leave plenty of room to work in if needed. I then moved on to the rudder fiberglass tips. There is one at the top and one at the bottom. I started with the bottom as it is the more difficult one as it requires a notch to go around the tailspring attach horns. 

I used my Dremel tool to cut out the notch and trial fit it. 

Onice I had the notch cut and trimmed so that the cap was even with the skin I marked a line 5/16″ from the edge to represent the river line. I used that line to drill a forward and aft hole to hold the cap in place. 

Now that I had the cap I place I put the rudder back on the vertical stabilizer to check the fitment. 

I was real happy with the alignment and fit. So I drilled the remaining holes on both sides. I then cleaned up the very aft end where the taillight will eventually be. I had bought an adapter ring from Cleaveland Tool’s a year ago or so. This allows you easily screw a taillight in with its threaded holes and not need a nut on the back of the screw as this is a very tight space to work. I needed the aft end to be flat and square so that the ring sat flat. 

The ring has six holes for blind rivets and two threaded holes for the taillight. The wiring for the taillight will run inside the cap and need to exit close to where it enters the VS. Since the rudder will be moving left and right I decided to make a racetrack shaped hole in the forward portion of the cap to allow the rudder to move left and right with the least amount of cable movement. 

I used a thin grommet to line the edge so it won’t chaff after I cut the hole. 

I stopped there with the bottom cap since I want to get my taillight and the connectors I will be using before I permanent rivet it in place. I then moved to the top cap which is much easier. 

I cleaned up the cap after drilling all the holes with sand paper. I also countersunk the skin for the blind rivets as well. 

I used the T-88 adhesive to help bond the cap and riveted it in place. I decided to fiberglass the seam on these as well so I mixed up some epoxy and micro-fill and applied a good layer on both sides. 

After that cured overnight I sanded it down to a nice smooth transition and put the rudder back on the VS. There is a forward portion cap that tops the VS and needs to be trimmed to match the rudder. 

Here you can see how much needed to be trimmed. 

So I made some marks that parallel the rudder cap and cut off the extra portion. 

It’s not required but I makes for a lot cleaner look to close up the open end of the cap. The easiest way is to cut a peice of balsa wood sheet to the shape and epoxy it in leaving it a 1/16″ short of flush. Then you can fill the rest with epoxy and micro to sand smooth. 

I did a couple of fiberglass lay ups in the inside of the cap to secure the balsa to the cap. I also filled in the forward side of the balsa with epoxy and micro as a rough start.  After that cured overnight I worked the forward edge until I got a nice clean gap between it and the forward side of the rudder. Once that was good I riveted it in place using more of the T-88 adhesive. 


I will come back to this cap after it cures to fill the seam and work the center section a little to better match the rudder cap with its alignment. While had the epoxy and micro mixed up I also added some to the leading edge of the wing tips where they didn’t quite line up with the aluminum. It was cured as well so I sanded those to a good shape. 

Now that the wingtips are getting closer to being done I riveted the tip ribs in place using more of the T-88 adhesive. 

So I will need to fill in the VS cap to make a clean look and work the horizontal stabilizer caps, they need trimming like the VS, to match up with the elevators. Other than being really dusty I don’t mind the fiberglass work. Maybe it just cause it’s a new skill, or lack there of, that makes it ok. Progress that’s all that maters to me, I’m getting close to being able to remove the wings!

Wingtip Hinge Stops

Time: 3 Hours

I got in the shop today after my weekend breakfast with Glenn for a couple hours. Today’s task was to make the wingtip hinge pin stops. These are made from a scrap plastic cutting board of all things. This is a pilot designed mod that has been used by many builders so I’m just copying their ideas. The idea is to cut the hinge pins so that they are a length that will slide into a chunk of the cutting board. Then that chunk can be screwed into the wingtip rib with a nutplate. Sounds weird but photos will help explain it. First up was to match drill the rib to the wingtip like I did on the right side. 

 Then I drilled for and riveted a not played 2 inches from the tooling hole. I’ve been shaped a piece of the cutting board two inches long into the shape of the rib.
 I clecko’ed the rib in place and reinstalled the wing tip on the wing as well as remove the aileron jigs so I could move them. 
 I removed the block and drilled tow #40 holes in the forward end of the block for the hinge pens to slide into. I marked the depth on the outside edge and return the block to the rib to mark the hinge pins to cut. After the pins were cut I return them to the wingtip and slid the block over each of the pin ends and screwed the block to the rib.

 What an awesome way to secure these hinge pins, I think they look great!

Flap Sensor

Time: 1 Hour

I did some organizing and shop cleanup yesterday and did a little work on the flap position sensor that I had worked on a while ago. My main goal was to clean up the bracket I made and to finalize the wire connections. I decided to use d-sub pins, male on the sensor side and female on the wire run side, to make the connections based on recommendations on the vansairforce.com forums. These are small and light and work well with the very small 26awg wire. To hold them together I used small shrink tube which worked well. I also ran the wire aft and down following the smoke system pressure line. 

I like how clean this looks and will be easy to cut the heat shrink off over the d-sub pins to do maintainance or remove. I also put a nutplate in place for the screw that holds the sensor bracket to the bulkhead rather than a screw and nut. That’s because I forgot that this area will be covered by the baggage floor pan and will make it inaccessible. 

Elevator Tips Riveted

Time: 4 Hours

I had a little time in the shop to secure the elevator tips to the elevator. First up was to countersink the fiberglass to accept the dimples of the elevator skins. I then dimpled all the holes except the four holes that had two overlapping skins where I countersunk them. 

I then cleaned up the elevator edges as well as sand and scuff the finerglass especially the flanges that would be riveted. Based on some other builders I planned on using structural adhesive to help bond the fiberglass to the elevators along with rivets. 

I mixed up this adhesive and applied it to the top and bottoms flanges and slid the tip in place.  These tips are riveted with blind rivets since there is no access to buck solid rivets. 

I plan on closing up the forward ends of the tips where they go over the counterweight. So I mixed up some epoxy and flox to start this process and fill in the gaps around the weight. 

When theses are cured I will cut some fiberglass that will lay over the from and get epoxied in place for structure. I will then be able to sand and shape this end and add balloons as needed to shape them. To finish up the day I grabbed my orbital sander and some 220 grit paper to work on the left wing tip gap. 

Thats where I called it a dusty day. 

Left Tip Looks Great

Time: 6 Hours

I came in the shop and removed the clamps and level to see that the tip stayed in perfect shape. I removed the tip and filled in all the chips and cuts in the aft end from all the cutting I had done on it with epoxy and flox. 

SSince I did all the trimming on the top where the tip met the wing I had a pretty uneven gap between the two surfaces. To fix this my plane was to used epoxy and micro balloons to close that gap. The process was to line the edge of the wing and its hinge with packing tape to act as a release agent. 

I used a putty knife to get the tape tight into the corner as I went. I then put the tip back in place with the hinge pins. Here you can see the gaps I was talking about. I mixed up the epoxy and balloons and applied a liberal amount making sure it was filling the gap. 
I also used it to fill several chips on the tip. 

While I was working on the fiberglass I moved on to the elevator tips that I had skipped a couple of years ago while working on the tail. 


Not hard work just trial and error as you trim and cut to get them to fit right. I will work on securing them in my next shop time.