First step was to protect the canopy from scratches and epoxy while the frame around it is built. Most builders use a roll on protective film, but many have complained that it is a pain to peel off. I decided to use blue tape. Notice how I left about a 1.5" border around the canopy perimeter.
The plans say to leave a 0.8" border... so I cut a 0.8" template and slid it around the perimeter while using a marker to trace it...
I then used a dremel (on low speed) with a sanding drum to rough the 0.8" border.. inside and out... being extremely careful to not go above the marked line...
Aft end too...
Everything below the duct tape will be fiberglassed...
Around the nose too...
With the canopy prepped, it was time to position it onto the fuselage and adjust the height to get a perfect spline... from the nose, all the way to the cowl. I used 2x1 braces to hold the canopy in place. I then used a tape measure as a spline (notice the t-square on top of my dummy engine to rest the tape measure on)...
Playing with the canopy spline allowed me to fine-trim the firewall to final height... here I am taking a jigsaw to the firewall! I then sanded the firewall perimeter smooth and symmetrical.
Final spline... look close, you can see the tape measure as a guide to how the cowl will be...
Next it was time to install temporary braces that will suspend the canopy in place while the frame is built around it. I cut two 2x1 braces.. one between the pilot seat and instrument panel... and another just forward of the center section spar.
I used bondo to temporarily install the braces flush with the top longerons...
I then made four of these little pegs out of 2x1's (about 3" wide).. notice the notch on the top so the canopy lip has a place to lock into. Also, notice how I cut the outboard side at an angle... this will help keep the canopy as far outboard as possible without interfering with the foam blocks that will be butted against the canopy later on...
I placed the standoffs on top of the 2x1 braces... and shimmed them to get the canopy level with the longerons, and at the height (waterline) that gave me the spline I wanted with the firewall. When I was happy with the shimming and canopy position, I "locked" the standoffs in place with clamps..
With the canopy in position, it was time to build the frame around it. I scavenged the hangar for as many foam blocks I could find leftover from any airfoil cores. I cut a bunch of small blocks for the side rails.. I cut a 45-degree bevel to butt up against the canopy bottom lip... this will create a 45-degree pocket for the flox corner all around the perimeter...
The forward section of the canopy was a little more tricky...
First, I traced out a template onto a piece of cardboard...
I then cut the cardboard and used it as a template to trace the outline onto foam...
The template was for the OUTSIDE perimeter... but I wanted to create a "shelf" so that the canopy lip would rest on... so I measured and drew a line 1" inboard...
I then cut the inner arc out... and drew the shelf line.. the tricky part here is that the forward section of the canopy is not at the same waterline... it moves up as it comes close to fuselage centerline...
Using a knife, I carved the lip away... leaving me with a "retainer" for the canopy...
Perfect fit!!!
The top part will be carved later... right now, my goal was to fill all the voids...
So far, all this was "dry fitted"... it was now time to bond all the foam pieces together...
Notice the duct tape on the top longerons... this is to protect the canopy layup from bonding the fuselage later on....
I used X30 pour foam to bond the pieces together... using micro would be too hard to sand later and cause uneven surfaces...
Bonded the nose side panels....
For the nose top, I milled out a pocket on the underside to clear the F6 bulkhead...
For the aft section of the canopy frame, I cut a bunch of wedges... painted pour foam on their surface and pegged them in place...
For the forward most nose section, I just piled a bunch of foam sections... bonded with pour foam... this will later be milled out to make the forward nose compartment post layup...
I then used pour foam in any small voids... and portions I thought needed height...
Now the REAL fun begins!!! Kids... don't try this at home!!! Time to carve and shape away!!!
I started by sawing away all the "chunky" pieces...
Then sanding, carving, sanding, carving, sanding, carving...
And then an "Oh crap" moment! As I was splining the nose, I noticed that the instrument panel, F28 bulkhead and forward nose wasn't splining right...
Hard to see in this picture, but if you zoom in, you can see how the F28 bulkhead is too low per plans for it to spline with a "long nose" mod. I had blended the canopy nose perfectly with the F28 bulkhead... but in order to blend the nose forward of F28 would require an almost straight line spline... I wanted more of a curved spline!
I got a sick feeling in my stomach knowing the amount of work that was ahead in order to get it right. But what the heck, what's another few more weeks of work in order to get people saying "wow, that is a nice looking EZ!"... I used pour foam all over the top nose...
After cure, I sanded away... getting the perfect spline I could possibly do... and boy was I happy with this one!
Taaaa-daaaaa!!!! The canopy frame is now ready for the outside layups!
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