Canopy

Tonight I started working on replacing the Vans canopy latch with the JDAir latch. Originally I wasn’t going to do this, because it requires cutting a larger slot in the side of the fuselage, and I didn’t want to risk it. Additionally, a lot of the 3rd party side panels are only designed for the standard latch.

At some point over the last year or two, Classic Aero started selling side panels that fit the JDAir latch. Looking at the actual modifications needed, and how much more solid of a latch it is, I decided to go ahead and change it out.

I downloaded and printed the instructions, checked the dimensions, then taped the template to the fuselage. Step 1 is to drill out the rivets holding the bottom bracket in place. This was easy enough. Then I drilled holes in the corners of each area which needs to be enlarged, and then used a small Dremel tool with a cutting wheel to complete the cut.

Next I’ll need to file the edges to a nice, flat, smooth surface, but I’m relieved to have gotten the scary step done without any collateral damage.

Today I installed the canopy guide pins, which are designed to stop the canopy from expanding at higher airspeeds (something that apparently happened on the demo aircraft).

I started by installing the pins on the canopy. Then, with help from mum and dad, we wheeled the plane outside and were able to install the canopy. From there, the pin position is marked on the canopy rail, holes are drilled, and a plate is riveted onto three top of the canopy rail.

It was unexpectedly difficult to fit the canopy onto the aircraft. The last time I did this, I did it by myself without trouble. But that was when the fuselage was on a rotisserie, and before I installed the remote canopy release. With the aircraft on wheels, the canopy has to be lifted higher off the ground, and because it’s a tail dragger, the angle is a little different. What really got annoying was that, unbeknownst to me, the remote canopy release handle kept rotating and catching on the edge of the bracket. I couldn’t figure out why I couldn’t get the hinge pins to insert, and assumed an alignment issue, but in actual fact the release handle was just getting caught and stopping the pins from being inserted. Luckily we had enough hands from people helping to figure it out.

I borrowed some playdough from the kid’s stash and marked the point where the pins contacted the rail. Then, following the instructions, used the paper template to locate the rivet holes, drilled everything, and riveted the plates into position.

When it came to time to test everything, the next unexpected issue occurred. I hadn’t installed the canopy since installing the seals, and consequently, the canopy wouldn’t close. After carefully checking that we didn’t have any other interference issue, I used some clamps around the roll-bar to compress the seals, until the locking pins could be driven home. Leaving the canopy closed for a few hours and sitting in the warm sun seemed to help the situation, and later in the day the canopy could be opened and closed fairly easily.

The canopy handle is quite flimsy, and if I was doing this again, I’d look seriously at switching to one of the 3rd party handles that are much more solid.

Tonight I painted the canopy fairing and peeled off the tape that forms the aft edge. for the most part it came out ok, but I was a little disappointed in the way the tape broke up on the aft edge as I peeled it away. I’m left with sections of jagged paint where small pieces of the electrical tape are still trapped under the aft edge of the fairing. I will need to carefully go over the edge to remove the pieces of tape.

Tonight I finished sanding the canopy fairing. Over the weekend I had given it one more coat of high build primer and picked up some more 400 and 600 grit sandpaper. I also happened across a curved sanding block with a radius of 4 inches, which is exactly the radius I needed.

The sanding went well and I am pleased with how it has turned out. I taped off the area that needs paint and will paint with a 2k primer (once it arrives in the mail). I opted for a spray can primer because I feel the spray pattern tends to be better than when I use my own spray gun system.

My biggest concern with the fairing right now is whether the tape, which forms the aft edge, will come away cleanly from the very thin layer of resin and fiberglass. will find out next week sometime.

Today I installed the LED light strip on the glare shield. I bought a cheap red LED light strip from Amazon, so I’m not sure how well the strip will hold up in the long term. To make replacement easy I installed some d-sub pins and left a service loop held down by the Velcro.

Before I installed the light strip I tested the lights to make sure they worked with a 9V battery, then cut the light strip to size.

The glare shield has a great insert for the light strip, and I had this wrapped up in no time.

I struggled to get a neat-enough looking wiring installation. My service loop for the fans adds extra wiring that needs to be held in place. I used a decent amount of spiral wrap to prevent wires from chaffing on the shop heads of the rivets. the result was ok, but not as tidy as I had hoped.

Tonight I installed the Aircraft Specialty glare shield, wired up the canopy defrost fans and canopy lock micro switch, and prepared for the LED light switch.

I had to uninstall the fans, test them, then install the leather glare shield. Both of the fans ran fine with a 9-volt battery. The glare shield fit is absolutely perfect, including the Velcro that holds the aft edge in place. Reinstalling the fans was slightly more challenging as the screws pass through the leather, but I was able to get it done without much trouble.

Wiring up the fans, I decided to use d-sub pins to connect them, in case they ever fail and need replacement. The pins are insulated with heat shrink, so replacing them would just require carefully cutting the heat shrink, then in-pinning the fan and installing a new one.

Everything is wired into a molex connector that came with the canopy wiring kit from Vans.

The LED lighting strip isn’t here yet, but once it arrives I can install it and wrap up the canopy wiring.

On Friday last week I started the remote canopy release modification, and I wrapped it up last night.

The original canopy release mechanism has a handle in the middle of the panel, towards the top. The handle is one end of a steel rod, and the other end is connected to a lever that sits behind the sun-panel. That lever drives a simple mechanism that extends and retracts the canopy hinge pins.

The downside of this approach is the loss of usable space on the panel. So Vans created a modification to relocate the handle. By using a cable instead of a steel tube, the handle can be placed anywhere. The recommended location is forward of the fuel selector valve, in a recessed area.

The modification was quite straight forward, and over several evening sessions I was able to wrap it up. I’ll have to remove the covers again so I can install the fuselage wiring harness, but that should be an issue.