Cracked Canopy Club

[mike.smith]

I was having no troubles handling, and sometimes even man-handling, my canopy material. Tonight was the night to start fastening the canopy. 5 rivets in and...

http://www.mykitlog.com/users/display_l ... 4838&row=1

At least it was only one crack, on the hinge side, and fairly out of the way. It was my own damn fault for trying to force a rivet. Oh, well, it could have been worse.

Mike Smith
Sonex #439

[daleandee]

At least it was only one crack, on the hinge side, and fairly out of the way. It was my own damn fault for trying to force a rivet. Oh, well, it could have been worse.

Mike,

I know that makes you heartsick but it isn't bad at all. On my first Sonex I cracked the canopy doing an engine run-up with out the canopy completely latched. The wind got under it and before I could catch it ... crack. That crack was a couple of inches long so I stop drilled the hole and then deburred it. I then took some scrap plexiglas and glued it over the crack with a light amount of clear silicone. It worked as I flew it to the ASA event in Crossville and no one even seen it unless I pointed it out or they knew of me whining about it online. I believe the silicone helped to keep the crack from spreading as well as deburring the hole after stop drilling it.

I don't believe that it is necessary to go that far but that's what I did and it worked for me. The other thing I would advise (too late now) is to use screws to attach the canopy instead of rivets as you can control (and feel) how much tension you are putting against the side of the canopy as you tighten the screws.

At any rate you are now the member of a pretty exclusive club!

Dale
N319WF

[mike.smith]

I thought about screws for the horizontal attachments, but I really didn't want to tap that many holes! Plus, as my riveting showed, it's not easy to get everything to align the way it's supposed to, so chances are I would have stipped some of the tapped holes.

I did use long machine screws and lock nuts to attach the canopy to the front and rear bows. Again, I didn't want to tap that many holes.

Mike

[Fastcapy]

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[tmobbs]

As a member of the "Cracked Canopy Club" I am wondering if there is a glue or cement that is effective on the "Sonplex" canopy material. I have tried Tensol 12 but in my experiments with scrap material, I have been rather disappointed that the fix is not very durable. Of course that may just be because of my lack of practice with Tensol.

I have a group of cracks in the rear corner on the starboard (hinge) side, most of them rising from the oversized bolt holes. I have "stopped" them with 1/16" drill holes, but I would like to seal them and restore the strength to that corner.

I understand that one or two builders have added patches - some of aluminium and some of "Sonplex" but I need to know what adhesive to use if I try either of those methods.

I would welcome advice.

Tim Mobbs
Sonex #1555TD Aerovee #0672
Bungay, Suffolk, England

[radfordc]

I used the IPS Weldon products on my old canopy with good results. http://www.eplastics.com/Plastic/plexig ... oCdl7w_wcB

[Corby202]

I used Sikaflex(295uv) to help hold the canopy to the frame. The Sikaflex primer (209N) bonds to the plastic well. Not cheap.

[jaywa]

I must be the president of the club as I went thru 3 canopies, all cracked during installation. In the end , in desperation ,I took the 'best' of the cracked canopies and formed a totally sandwiched frame using developed Al strips about 50 mm wide mounted onto the tubular frame ( no holes in the perspex , only in the Al ) , glued in with Sikaflex , and test flew with it for a while. The precision wasn't great , but it worked.

Finally , with my one remaining new canopy, I got expert help and now use that with the sandwiched canopy as a spare

[Sonex570]

I also wen through one years ago, I believe it was before Sonex changed the recipe and put a little bit more flex into the mix, going to wait till it gets nice and hot outside to try attempt canopy number two lol