Chapter 25 - Section 3A

Filling and Sanding - Canopy

 

Fill and Sand the Canopy

I took a break from sanding and worked on installing the engine, baffles, dual actuator control canopy and oil cooler etc. Now I am back to filling and sanding. At this point, the canopy seems to be a good candidate.

 

I started sanding the canopy after I added the canopy hoop (Chapter 18 - Section 11A). Since I pre-filled the aft lip, I decided to complete the skirt as well. It's been so long since I last sanded the wings, I almost forgot the mixing ratio of West System epoxy and the amount of micro to add. Fortunately, I kept good notes on my website for my own reference.

Here's the before and after shot.

I turned the canopy over and sanded down the rough edges (from the layups). Can't believe what a lousy job I did in those early days. I also had to re-tape the window edges (blue tape) because the spray-lat is starting to peel at the edges.

In the heat of roughing up the underside of the canopy, I forgot how crucial the edges (seams) were. You guessed it, I ended up sanding off the aft edge of the passenger side. Now I have to re-build that edge/seam when I am done with the fill and sand.

I took me almost 3 evenings to sand down the underside of the canopy. I was glad when it was done!

Here's a picture after priming the canopy interior. This time I did not have any orange peels or drips / over sprays. The picture left shows the completed Zolatone spray. They turned out reasonably well!

 

This is going to be a bit out of sequence since there is not much in the Plans on the finishing chapter. I am at the point that I either start the electrical or finish sanding the rest of the plane. I decided to tackle the internal surfaces first before starting the electrical because I do not have to remove or wrap all the electrical wiring prior to shooting paint.

 

Fuel Line Covers

I have a couple of fuel lines that cut across the back of my front seats and they need to be protected. I decided to make a cover for them. Actually, I made it a bit wider to accommodate additional wires that may need to cut across from the center console to the sides of the fuselage (if needed). I cut up a 20" paper tube lengthwise (that came with the BID) into halves as a form for my covers. I trimmed and fit the paper tube halves between the center console and the rear armrests. Then I taped down the surfaces with packing tape as mold release. I added packing tape to the seat back and 5 min. epoxied the paper halves onto the seat back. I wetted out 2 layers of BID and laid them over the forms.

 

After cure, I popped the covers off and trimmed the edges. Then I drilled 3 holes on each side and secured them with sheet metal screws. Notice the cover is wedged and screwed down between the left rear arm rest and the center console.

 

The surfaces were scuffed up as a preparation for micro, primer, Zolatone paint and clear coat.

 

I completed the interior priming and painting (zolatone) as discussed in Section Ch25_8.

 

Priming Canopy Exterior and Seam Treatment

One of the most 'looked at' areas of our airplane are the canopy match lines (seams) and the lines around the windows. I thought I have done a relative decent job in making the seams 'pleasant' until a friend of a friend (Noe) came by to check out my project. Noe does sanding, fill and paint airplanes for a living. Obviously, he was not as impressed as my other visitors. After some real constructive pointers and discussions, I asked him to help me to 'improve' my lines . Here's some of the improvements he helped made:

 

You might have noticed, I purchased my turtle back from FeatherLite. and canopy/ rear windows from Todd Canopy. Amazingly the curvatures on both match very nicely, IF you mount them at the exact planned locations. Noe pointed out that once the canopy is painted, the dark edges will be more pronounced due to the dark line on the white surface. He recommended adding micro fillet along all window edges with the help of fine line paint tape (1/8") from Aircraft Spruce. Once primed, I peeled the tape off and you can see the fine line and fillet. You can also see remnants of my Spraylet coming off when I removed the masking tape over the fine line paint tape. This process will be repeated when I final paint the canopy. The white coating here is just the primer.     
Picture left shows my primed canopy the first round. It was beautiful at the first glance especially from a distance. Closer inspection showed bumps and orange peels . I found similar flaws in almost all my parts - I was not happy!
I decided to re-sand, re-glaze, re-mask and re-prime. It looked much better this time.
After primer, I decided to remove the Spraylet and tape residue on the canopy. I painted the Spraylet on the canopy at least several years ago. I remember I painted 3 layers on the canopy. I was happy that the Spraylet peels off easily. The electrical tape residue, however, was not coming off at all. After some searching and discussing options with other Cozy builders, I found the cleaner (also suggested by Tom Kennedy) that you can buy from Aircraft Spruce. It worked wonderfully and the old duct/electrical tape residue just wiped off. No hard scrubbing required. As you can see the result on my canopy.