Canopy questions.

[Brad]

Yes Rick, that’s what I meant to say.

[at7000ft]

In the interest of possibly helping someone else with their canopy installation I will answer my own questions to the best of my ability.

1) The adhesive does seem to be strong enough to hold the plexiglass to the skirt. I did remove one cleco at a time and installed a screw and nut in its place before moving on to the next hole. The 5200 seems more like rubber and less like “glue” than I was expecting, but it does seem to hold well.

2) The clecos did not crack the canopy, fortunately! I did put most of them in from the inside thinking that the fiberglass skirt would be stronger than the plexiglass when it comes to holding the expanding end of the cleco. There are about 5 holes in the front of the canopy where you must install the clecos from the outside, these were fine and did not seem to cause any damage to the bubble.

3) The inward curvature of the bubble did not cause any problem. When the bubble is clecoed to the skirt they actually kind of “average” each other out and work well. At the rear of the canopy the skirt and bubble are not parallel to each other and the bubble in this area is strong enough that it doesn’t pull up parallel to the skirt as it does at the sides, this is not problem because the adhesive fills the gap...however with the screws perpendicular to the skirt, as they should be, they aren’t perpendicular to the plexiglass so I will need to be careful when tightening these nuts because they won’t come down flat on the bubble.

4) The clecos came out easily using a twisting motion as Dan suggested.

Other thoughts;

1) I set the canopy, as soon as I was done bonding it, on the fuselage in the hope the fuselage would hold the canopy in the correct shape as it dried. It seemed to work well.
2) I was concerned the adhesive would shrink and since the canopy was on the fuselage I would be unable to add more adhesive to fill the void, that turned out to be a non issue. The adhesive only shrank a very small amount.
3) The bubble was held in place while bonding with 3/32 clecos, after curing I updrilled it with a #26 bit for the #6 screws. This means I was only able to chamfer one side of the plexiglass hole, hopefully this won’t lead to cracking down the road. I’m not aware of this becoming an issue for others.
4) This one is out of sequence. When drilling the skirt to the canopy the holes at the front were drilled after the skirt and bubble were set on the fuselage. I got this idea from someone’s builders site and it worked out very well.

Brad

Brad - concerning item #4, "When drilling the skirt to the canopy" does this mean drilling the skirt to the bubble?

[75kr@att.net]

I might add that when drilling the plexiglass through the fiberglass skirt be sure to use plexiglass drill bits.
Kevin

[Brad]

In the interest of possibly helping someone else with their canopy installation I will answer my own questions to the best of my ability.

1) The adhesive does seem to be strong enough to hold the plexiglass to the skirt. I did remove one cleco at a time and installed a screw and nut in its place before moving on to the next hole. The 5200 seems more like rubber and less like “glue” than I was expecting, but it does seem to hold well.

2) The clecos did not crack the canopy, fortunately! I did put most of them in from the inside thinking that the fiberglass skirt would be stronger than the plexiglass when it comes to holding the expanding end of the cleco. There are about 5 holes in the front of the canopy where you must install the clecos from the outside, these were fine and did not seem to cause any damage to the bubble.

3) The inward curvature of the bubble did not cause any problem. When the bubble is clecoed to the skirt they actually kind of “average” each other out and work well. At the rear of the canopy the skirt and bubble are not parallel to each other and the bubble in this area is strong enough that it doesn’t pull up parallel to the skirt as it does at the sides, this is not problem because the adhesive fills the gap...however with the screws perpendicular to the skirt, as they should be, they aren’t perpendicular to the plexiglass so I will need to be careful when tightening these nuts because they won’t come down flat on the bubble.

4) The clecos came out easily using a twisting motion as Dan suggested.

Other thoughts;

1) I set the canopy, as soon as I was done bonding it, on the fuselage in the hope the fuselage would hold the canopy in the correct shape as it dried. It seemed to work well.
2) I was concerned the adhesive would shrink and since the canopy was on the fuselage I would be unable to add more adhesive to fill the void, that turned out to be a non issue. The adhesive only shrank a very small amount.
3) The bubble was held in place while bonding with 3/32 clecos, after curing I updrilled it with a #26 bit for the #6 screws. This means I was only able to chamfer one side of the plexiglass hole, hopefully this won’t lead to cracking down the road. I’m not aware of this becoming an issue for others.
4) This one is out of sequence. When drilling the skirt to the canopy the holes at the front were drilled after the skirt and bubble were set on the fuselage. I got this idea from someone’s builders site and it worked out very well.

Brad

[Brad]

I have the pre-trimmed bubble which fits pretty well. I have a few questions concerning attaching the bubble to the frame. I plan to attach it with screws and the 3M 5200 adhesive.

1) The bubble at the corner where it turns and goes up the turtle deck is about 1 and 1/2 inches inboard of the frame on each side . It takes a fair amount of “push” to get it where it belongs. Is the adhesive strong enough to hold it when it cures?

2) Has anyone cracked a canopy using a cleco in the holes?

3) The bubble is curved inward at the sides, ie. not parallel to the frame sides. Has anyone experienced this and did it work out OK after bonding and screwing the canopy to the frame?

4) Will I be able to remove the clecos after the adhesive cures?

Any other tips, hints, suggestions etc. are more than welcome!

Thanks,
Brad Carter