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I know it's possible to blow a canopy bubble and I intended to do this for a while.  However, I found a source of canopies that makes this effort mostly worthless.  I bought it from Todd Canopies.  Todd is a very nice guy who makes canopies for various aircrafts. Not only does he sell perfect canopies, but he is very easy to deal with (very accommodating).  His prices include crating.  I ordered my canopy at the same time a friend ordered five canopies for another type of aircraft.  That allowed me to share a crate and thus, save significantly on the shipping cost.  While Todd's prices are already very competitive, he may make special deals for batches of canopies ordered at the same time.

The following picture shows an optically perfect canopy with no deformations.  Please take note that the canopy is mis-positioned on the fuselage (front should be the back) on the picture dated May 28th.

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First thing we did (my wife's father was helping me for the canopy installation) was to check the canopy for fit.  I felt comfortable sitting in the airplane with a pair of headset... GOOD!

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Next, after centering the canopy, we marked its position on the fuselage.  A second positioning line may be noticed on some pictures.  This is because at one point, we decided to move the canopy back a little bit.  The purpose of the yellow tape pieces with the alignment marks was to ensure exact positioning of the canopy each time we moved it.

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Fitting the tube frame with the canopy has been a simpler job than expected.  For minute adjustments, I used two pieces of 2"X4" with 3/4" holes drilled.  I also used a heavy gauge steel tube to straighten the first two inches of the tube so it fits in the canopy arm rear tube.

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This is the fit of the bubble with the rear canopy tube installed and drilled.  For a reason, I have a pretty large gap on the rear left side of the canopy between the bubble and the fuselage.  The right side is just perfect.  I thought of various ways to correct this.  One would be to cut the canopy and make a fiberglass frame (suggestion of Todd).  Another approach would be to split the canopy and have the rear portion fixed on the fuselage.  This would allow me to correct this and to hide any defect.  Gerald Kelley (see Other Projects on this web site) has a split canopy.  I also tried on a scrap piece of acrylic to reform the material using a heat gun.  Todd and others are very nervous about using this method, but it worked well on my test pieces.  I'll check with a plastic expert before doing this "for real".

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July 3rd update: I modified the shape of the rear left portion of the canopy using a heat gun.  I'm satisfied with the result. You may notice the advanced acrylic forming tools being used. :-)  During the heating session, the heat gun was actually held further from the acrylic in order to avoid concentrated hot spots.

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To install the front tube frame, it is required that a "volunteer" sits in the plane and hold the tube in place while "I" drill it.  I would have volunteered, but frankly, it's pretty hot in there and I had a good excuse not to take that job... I want to be the one risking my canopy when it is getting drilled.  So, my father in law took seat!

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Next, we tried opening the canopy to see that everything goes well... IT DOES NOT!  The canopy cannot be raised to the specified 67 degree opening angle because it pushes the cowling past 50-something degrees.  The maximum practical angle I can obtain is about 50 degrees.

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I modified a gas spring to see how the canopy is at a reduced angle.  For this, I just clamped the spring shaft in a lathe (which has jaws that don't damage the shaft) and I tapped more threads.  Then, I cut 1-3/8" of the shaft.  At that reduced length, the canopy opens to 45 degrees, but the springs are nowhere strong enough to hold the canopy open.  I ordered two 80 lbs springs from McMaster to replace the original ones (that are 40 lb springs).

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I made a special tool for dimpling the 6-32 screw holes.  I used a screw from which I removed the threads (on a mini lathe).  Then, I drilled and countersunk a piece of 1/4" aluminum.  The holes need to be drilled to 7/64" and they come just fine for the 6-32 screws once dimpled.

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