This is the first post in a very long time, mainly because I’ve only been working on a single thing since halloween. So far I finished all the work on the tail and the canopy. I ended up making a new empannage fairing since I didn’t like the one Van’s supplied. I also made the entire canopy fairing out of fiberglass for a few reasons. One reason is that in order to get the canopy frame to clear the turtle deck, it had to sit slightly outside the recommended position. This means the metal skirts would either have a large gap or an unsightly bend in them. Since I was making side skirts out of glass, it made sense to make the entire thing out of glass.
I’m using the following items in my fiberglass kits:
West Systems Epoxy Resin and Hardener from the local West Marine
The Following items from Spruce:
Rutan Bi-Directional 8.8oz cloth
Eglass 8.7oz Bi-Direction Tape 3″ width
1lb 3M glass bubbles
1lb Flocked Cotton Fiber
Dacron Peel Ply
Various mixing cups, tongue depressors, gloves, and other random shop supplies.
I started with 5 yards of fabric and ended up running out halfway through the canopy fairing, so I ordered another 5 yards of clothe. If you’re not doing a custom empannage or canopy fairing, 5 yards is more than enough to do the entire plane.
I started with closing out all the tail surfaces. I’m using the method from Stu’s Aircraft Factory with flox over foam. I picked up some foam core from Lowe’s and cut them into shape, then covered it with 1/8 to 1/4″ of flox all around to glue it into place. The foam is just there to take up space so don’t worry about getting the shape perfect, just make sure you leave room all around for the flox. I mixed the flox into the epoxy until it was a similar thickness to Elmer’s Paste and then inserted glued it into the recesses. Once it hardens you can take a DA sander or some 60 grit by hand and sand it down flush.
After this was a nice thick layer of micro. For anyone new to this, just mix the epoxy together and start adding glass beads a little at a time until it becomes the consistency of cake icing. This is what I used for my first layer of micro. Make it thick enough cover all the low spots, but the more you add, the more you have to sand off later, so find a nice happy median. Shape it into place with some 60 grit.
After this dried, it was another coat of micro, but instead of thickening it to cake icing, I made it thinner so it still ran off the mixing stick but had a bit of body to it. You want this to fill in all the pin holes and sanding scratches from the 60 grit you used to shape the thicker micro in the last step. Once this thinner layer dries, you can sand with some 220/280 grit and if there’s no pinholes, move on to high build primer.
The control surfaces were up next and needed a bit more work. Before riveting on the end caps to the elevators, I riveted in an AN4 nutplate in the tooling hole next to each of the lead counterweights. After riveting on the fiberglass end caps, I put a layer of thick micro in the gap between the metal and cap. I then laid up a single layer of glass cloth to span the gap. After sanding that down, I did more or less the same filler technique: thick micro/60 grit sand/thin micro/280 grit sand/pure epoxy for pinholes/280 grit sand/high build primer/500 grit sand. These aren’t perfect, but I’m planning on having the painter do the final sanding and prep because I’m not good at prepping and painting things. On the left elevator I got everything filled with foam and flox and sanded down, except for the 3 inches behind the counterweight. I left this open until the end and then added washers on a bolt into the nut plate I installed earlier. With the electric trim in the left elevator it took 6 or 7 large fender washers plus the bolt to slightly over balance the elevator. Once its painted I can drill out the counter weight to get the balance perfect. The right elevator didn’t need any extra counter weight.
Next up was the vertical tail and rudder. The bottom cap on the rudder needed to be trimmed to clear the tailwheel spring, so thats where I started. After I made the initial cuts, I noticed that the gap around the bottom of the rudder control horn was larger than I was hoping for. I ended up cutting off the front of the cap, removing a 1/4″ strip, and then glassing it back together with 4 plies of glass. While I was floxing in the mount for the Fly LED taillight, I floxed in about 1.5″ of the inside of the cap. There was a bulge and this allowed me to sand the bulge down until everything was nice and flush. I then added in some screw holes with matching nutplates and countersunk them. I want this to be removable since there is a light and wiring running behind it. After it was all trimmed up, I used the same procedure for micro and finishing as the control surfaces.
The top of the vertical stabilizer and rudder were harder still. Here’s how the original caps lined up from Van’s.
The vertical stabilizer cap was bowed out really wide and the top contours didn’t line up. I really didn’t like the way this looked so I decided to fix it. I had to cut a seam down the middle of the stabilizer cap, pull it into place, and glassed it back together with 4 layers of cloth. After that, it was close enough to hold its shape with the flox/foam and get the gaps right with micro. I decided to rivet and glass this in with a single layer of clothe just like the elevator caps. Here it is after the first thick layer of micro and some initial sanding. Finishing this up was the same procedure as before.
I don’t think I actually got a final picture of the top of the rudder, so I apologize for that.
~Paul
(Total Build Time: 769.6)