Cracked canopy

After 22 years of service my RV-4 canopy cracked. I don't know why after all these years. The crack was about 6 inches long on the right side of the canopy by the passengers head when I 1st noticed it. I stop drilled it, but it has grown 2 more inches. Does anyone know of a way to fix it other than installing a new one? I was wondering if there are any glue products on the market that I might try?

Weldon 16

Get a tube of IPS Weldon 16 acrylic cement. It's about $12-15 depending on source...available from many sources online.

It's extremely runny cement that dries quickly, so be very careful with it.

The cement will dissolve/melt the edges of the crack together and do a good job of bonding.

You'll probably need to sand the new joint with 400 grit to get rid of excess cement and then use a good canopy polish kit (a small Micro mesh kit from Spruce (about $25)) to continue to polish until clear again. Expect some optical distortion where the joint has been smoothed....but depending on location this might not be a big deal.

Good luck,
Mike

Interestingly I am told that IPS Weldon 16 is just dichloromethane (Methylene Chloride) which you can buy here in the UK for about ?5 ($7.75) a litre.

John

Did the Weldon repair

Thanks for the replies. I did some online research and decided Weldon #4 was the best choice. It is like water and will wick into the crack. It bonded the plexiglass very well, but there were still some stop drill holes and you could still feel the crack edges. I got some Weldon 16 and ran a bead down both inside and out side of the canopy. This also filled the stop drill holes. I got a Poly-Sand kit from Aircraft Spruce and started with 400 grit sand paper. It sure looked ugly for a while. You can still see the crack, but it is bonded very good and you can't feel it when you rub your hand over it.