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Method for JB Weld back window repair

Bruceman

New Member
Joined
Oct 3, 2018
Messages
3
Location
Central New York
I've searched the forum and have found remarks from people who have repaired the cracked frame on their midgate window using JB Weld. What I can't find is any description of how exactly it was done. The midgate window on 2011 AV has several separations in the frame. I'd like to repair the frame using JB Weld, but I'd love to get the benefit of anyone's experience who's already done it. What I'm mostly wondering is how the epoxy is formed. That is, how do you get the epoxy to be even with the rest of the frame? I've thought of trying to use something like masonite with packing tape as a release layer. I've never used JB Weld in this way before, and I'd hate to really munge the frame on my window. So I'm hoping to pick the members' brains if possible before I try this.

Thanks,
Bruce
 
I did it twice with JB.  Both times I clamped the plastic frame to fit snug to the glass.  It holds well for a while, but will eventually break again as you experience temperature fluctuations.  I think the problem with JB is that it dries harder than the plastic.  I tried again with Permatex black rtv.  It seemed to be more forgiving, but I can't speak for its longevity as I sold the '03 to which I did the repair.  The '13 I bought also has a cracked frame and I have not repaired it yet.  I don't think they ever perfected the frame on these rear windows sadly...      I'm currently debating about whether to try RTV again, or just get a safelite replacement rear window assembly.  I'd love to hear from those that have chosen safelite if these will eventually get cracked trim as well?

That said, the reason I've not felt the need to repair immediately is because even with the cracked frame, it still seems to seal well in the '13 ( no leaks yet ).  I also always park outside, so it gets plenty of rain exposure.  When I park on a hill, I always make it a point to not leave the front end of the vehicle lower.
 
I left a 3/4 inch gap in mine when I did this.
 
I used clear RTV sealer and have had it for years in my 2008 without leaks or peeling off so far.... I believe it is good because it will flex instead of being rigid.
 
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