The plans state to do the following schedule:
1 - BID at 45 overall
2 - BID at 45 overall
3 - UND sides only (lap 3" onto front and rear)
4 - BID front and rear only
5 - UND sides only (lap 3" onto front and rear)
Some Long-EZ pilots have complained that their canopy frame lip tends to warp (the front corners come up a bit during flight). I haven't gather enough evidence as to the root cause - some say it's due to thermal expansion, others say it's because of aerodynamic forces, perhaps it's if you have square corners, who knows? The point is, previous builders suggest adding a layer of carbon fiber on top to try and stiffen the frame up. Some have gone as far as doing the entire frame out of carbon; however, I didn't like that idea since: 1) carbon is more difficult to work with, and 2) carbon doesn't like to be bonded with aluminum (galvanic corrosion issues), which might cause issues later when mounting the aluminum hinges, latch hardware, etc. So I decided to do the same layup schedule as the plans, and simply add a single layer of carbon fiber at the very end.
My revised layup schedule:
1 - BID at 45 overall
2 - BID at 45 overall
3 - UND sides only (lap 3" onto front and rear)
4 - BID front and rear only
5 - UND sides only (lap 3" onto front and rear)
6 - carbon fiber overall
I should also note that rather than doing this layup from the F28 bulkhead to the firewall as the plan states, I decided to do the ENTIRE top surface of the fuselage - nose tip all the way back to the firewall.
I pre-cut all fiberglass and carbon fiber plies. I also made sure any fiberglass surfaces that were going to get bonded with new layups were sanded dull and prepped (canard inboard edges, center section spar inboard edges, firewall edges, etc.)
With all the fiberglass plies pre-cut, it was time to mix up some epoxy! I started out by slurrying the foam - working with one section at a time. Notice the sharpie line - this was to help lay the fiberglass at the proper 45 deg orientation.
Notice the gray tape stops just shy of where the instrument panel is. This was done on purpose so that everything forward of the instrument panel will bond to the fuselage permanently. Also, notice the plastic bag taped to the elevator to protect it from any epoxy.
Michaelah and Liam were here to help with this layup! They are two USF mechanical engineering students that have been helping me with my project!
A close up showing where the SIDE canopy lip transitions into the FRONT canopy lip.
What followed next was 7 hours of pure work! I was so focused on making sure I didn't miss any steps that I didn't take any pictures in the meantime (the time lapse camera should have captured the major items).
The result was a thing of beauty!
I let the layup cure for 48 hours, as the plans says....
We followed the plans on how the layup bonds with the canopy. First, we painted plain epoxy onto the canopy lip (everything below the gray tape). The first fiberglass ply gets tucked into the 45-degree groove, but stretches back up onto the canopy and overlapping onto the gray tape. This creates a small pocket, which is filled with flox. The remaining plies then get laid on top of this flox corner and butt up against the canopy.
This is a good shot showing the first ply overlapping onto the gray tape, while the other plies were laid on top of the flox groove and butted up against the canopy.
A close up of the aft end. I did not extend the carbon fiber ply onto the center section spar since it is much stiffer than fiberglass and did not want to complicate things...
Notice how the side skirts never overlapped below the gray tape... this was to prevent the layup from bonding to the fuselage...
I applied peel ply wherever there was a transition. Also, notice how I stopped the carbon fiber ply at the F28 bulkhead. I only added the carbon fiber to stiffen the canopy frame so figured the forward nose didn't need it.
That is one smooth nose spline!
With everything cured (for 48+ hours), it was time to trim things up! I used a dremel with a cutoff wheel, and the lowest speed possible...
It was so slow in fact, that it barely made a mark onto the fiberglass... but after a few passes, it started to make a crease... this was to make sure I wasn't going through the fiberglass and into the canopy...
I went all around the aft arc...
Peeled off one end...
And it peeled right off! I was surprised how easy this was! Nerve wracking at first! But once I got the hang of creating a crease with the dremel on a low speed setting, and assured I wasn't eating into the canopy, it was smooth flying!
For the canopy rails, I switched to my multi-tool. Again, on the lowest speed setting and going extremely slow. The idea wasn't to cut through the fiberglass, but to simply crease it...
This allowed me to use a spatula to separate it from the gray tape...
...and fold it forward...
By pulling on it a little, the strip then comes right off... leaving a clean crisp line! The final line is later defined when the canopy frame is filled with micro during finishing process.
The forward lip, I switched back to the dremel... again, not cutting! Just making a crease...
And then pulled on it until it peeled off...
I did measure it from the firewall to make sure it was symmetrical on both sides...
I then marked it...
Next, I took leftover Nylaflow tubing (leftover from the rudder conduit), and played with the forward canopy frame cutout. The pink string it where the instrument panel is. I wanted my canopy to extend over the instrument panel, but transition aft with rounded corners. After a few measurements, I marked the spline...
With everything marked, it was time to cut! The side skirts were first, since those were super easy... straight line along the top longerons... being EXTREMELY careful to not cut into the longerons (this isn't so difficult to do since there is some space between the layup and top longeron).
The aft end is cut along the line drawn earlier. I took 3 deep breaths and just went for it!
All the way down to the top longeron waterline...
The front end was the trickiest since it is a curved spline. I used the dremel for this one...
Slowly but surely, I cut the marked line...
With the glass layups cut, I still needed to cut through the foam underneath... so I took a knife and cut away! I was careful to not cut into the instrument panel when I came across it...
Aft end needed foam cutting too! I'm glad no one walked in at this moment; else they would have thought I've gone mad and trying to murder my plane!
Since I never really bonded the foam blocks to the gray tape protecting the top longerons, I lifted up along the edges of the canopy frame....
... and off it came!
Great shot showing the clamps holding the standoffs that held the canopy in place while the foam frame and layups were completed...
The aft end "turtle nook"... glad to see the pour foam really filled all the voids between the wedges...
And there you have it! Canopy outside layups complete! Next up, canopy inside work begins!
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