Sealant for windows/windshield?

[rodsmith]

With the fuselage painted its now time for permanent installation of the left side rear window and in the near future the windshield. My left side rear window is not standard. I built the frame for it out of angle. I will install it using aluminum angle on the inside. Thinking it should be sealed against the outside frame, not sure what product to use. For the passenger door window, I sealed it into the composite panel using sikaflex (black), seemed to work ok in that application but definitely messy and not shure how easy it would be to remove. Also thinking the base of the windshield needs to be sealed to the boot cowl, so rain doesn't get driven under the trim piece and into the cockpit.

[Nev]

I masked the main windshield off and used Sikaflex. So far it's worked well. I used Sikaflex for all my windows and skylight,

[Lee]

My current plan is to use 3M Window Weld. 08609. Same stuff the windshield guys used to install windshields. Bought it at my local auto parts/aviation supply. Used it on a Sonex canopy and was very happy with the results.

[Nev]

Is this an adhesive, or a sealant ?

[Lee]

Adhesive. According to 3M it's a One-part fast-curing urethane adhesive. In my experience it is very flexible and bonds very well. Consistency is very much like silicone. I think it would be an excellent choice where glass (plastic) is bonded to a flat surface. Probably not a good choice for the side windows where they sit in a channel. The windshield guys use various knives to cut windshields free. I can't compare it to Sikaflex since I haven't used it. I just did a quick lookup on Sikaflex. It looks like they have both polyurethane sealants and adhesive-sealants. Window Weld would probably compare closer to the later. Which Sikaflex product(s) are others using?
Lee

[rodsmith]

I used Sikaflex 211 which is black. My only concern is it seems like it would be hard to remove if necessary to replace a window.

[Battson]

Some stuff they use on car windows is both an adhesive and easy to remove, if you've ever watched them peel it off - it comes away easily once you get it started.

[Lee]

Many of the RV guys favor gluing their canopies to the canopy frame. They also advocate putting mechanical fasteners in the corners of the canopy. I guessing they are somewhat adverse to canopies peeling off at 180 mph...

[geraldmorrissey]

In 4,400 hrs on my Cessna 150, no windows were ever replaced. And I had two bird strikes. One that broke my cowling. But it was always hangered. If your plane will be tied down outside but with a cover over the windows, my guess is you will never replace a window. The sun seems to craze some plastics. Used to see crazing in So Cal on unprotected windscreens.

[Battson]

In 4,400 hrs on my Cessna 150, no windows were ever replaced. And I had two bird strikes. One that broke my cowling. But it was always hangered. If your plane will be tied down outside but with a cover over the windows, my guess is you will never replace a window. The sun seems to craze some plastics. Used to see crazing in So Cal on unprotected windscreens.

I think this is a very relevant point. Very few occasions call for a windscreen to be removed.

[Rollie]

I simply used clear silicone caulk from Lowes. Easy to find, easy to use and seems to be holding up well. Windows have all been in for 5 or 6 years, around 425 hours on the plane now and no issues, no leaks. I've flown through rain and it's been tied down outside in thunderstorms while I'm on trips and didn't have access to a hangar and never leaked. The fancy stuff sounds nice, but we aren't building pressurized airliners here.