What's new
Van's Air Force

Don't miss anything! Register now for full access to the definitive RV support community.

Targa strip, glue or screw

FrequentFlyer

Active Member
The targa strip on my RV-7A tip up has decided to separate from my canopy due to heat. It was glued on with Sikaflex but not the UV 295 stuff. The Sikaflex didn't adhere to the plexiglass but is strongly stuck to the aluminum. It lasted about 100 hours.

I'm considering screwing the targa strip to the canopy instead of regluing. Are there a you downsides to this?

Also, the plexiglass is screwed into the frame with counter sunk screws. My thought was to drill back through the existing holes and into the targa strip. Any issues with attaching the targa strip over top of the counter sunk holes in the plexiglass?
 
Strip

I only used screws, lot a of them! I dimpled the aluminum strip and used flush screws. Then matched the white paint with a white vinyl. It's a little more work, but worth it IMO
 
Did the plexi have the primer on it, I can't imagine this stuff separating from it if it was prepped correctly?
 
I know it is a pain to post pictures here now, but I would love to see some of the targa strip install. I would like to see others before I make mine.

I want to do it on mine. I like the idea of vinyl - maybe the fake carbon fiber vinyl to match my spinner!

I did find a bunch of pictures on google, but would like to see how others have done the install.
 
Last edited:
I used a urethane adhesive, but also put in 5 or 6 rivets to hold it on in case the glue separated. Bonding to acrylic is a challenge.
 
If you haven't cut your canopy yet, another option... Make the split halfway along (front to back) the rear (fixed) canopy bow. The forward part of the canopy will then extend beyond the (moving) canopy frame, and when closed will sit on top of the rear bow. No Targa strip required.
 
targa strip on tip is loose at the side

Does opening the canopy on one side put stress on the Targa Strip?

My targa strip came loose for about 6 inches on the pilot side. Flying only 20 hours. I glued it a second time and the strip came loose in the same spot. When I look close as I open the canopy there is flexibility in the canopy and I'm wondering if I am slowly putting a lot of stress on the Targa Strip from the flexing. I'm thinking of gluing it again with epoxy, but would putting a screw thru it be a better idea? One of the #6 screws that goes thru the canopy and frame is near here and I could open the hole thru to the outside and put the screw thru the targa strip. But will it flex enough if I put a screw in? Or might I move the stress to some other place on the strip and it will separate someplace else. I don't want that.

If I do fix it again, do I need to stop opening the canopy by the handle and open it be the center instead? I don't like that idea but do others avoid opening the canopy by the side handles?

thanks
 
Does opening the canopy on one side put stress on the Targa Strip?

My targa strip came loose for about 6 inches on the pilot side. Flying only 20 hours. I glued it a second time and the strip came loose in the same spot. When I look close as I open the canopy there is flexibility in the canopy and I'm wondering if I am slowly putting a lot of stress on the Targa Strip from the flexing. I'm thinking of gluing it again with epoxy, but would putting a screw thru it be a better idea? One of the #6 screws that goes thru the canopy and frame is near here and I could open the hole thru to the outside and put the screw thru the targa strip. But will it flex enough if I put a screw in? Or might I move the stress to some other place on the strip and it will separate someplace else. I don't want that.

If I do fix it again, do I need to stop opening the canopy by the handle and open it be the center instead? I don't like that idea but do others avoid opening the canopy by the side handles?

thanks

It depends on the unique aspects of your canopy installation. however, there is definately some twisting as you open the canopy.

Epoxy is a poor adhesive for acrylic. Even West will tell you it is weak at best in adhesion with acrylic. Their G flex will do much better, as will urethane adhesives designed for acrylic, like the sikaflex 295. I used a UV activated, urethane adhesive from mcmaster that stated it had a strong bond with acrylic. I have had no separation on my 6's targa strip in 600+ hours. I cut 45's at the aft, lower corners of my targa strip to avoid the type of issues you are having. Can't say whether or not that is a factor in my success, but suspect it might be.

I used sika 295 on the 10 windows and did some testing. When used with their activator and primer, it creates a strong bond to acrylic. However, the total package is north of $100 for even a small amount.

Larry
 
Last edited:
Sika will not adhere without primer!

If Sika ist glued on with primer, it wont let go ...

Epoxy has nearly no adhesion on acrylic ... if you scuff very rough, you get some, but still poor. If you have to put epoxy onto acrylic, I would use primer and scuff the primer, so you get some adhesion.
 
Last edited:
I deep into Sika'ing my canopy, windshield, fairings, targa strip etc right now.

Sure seems pretty odd that its bonded to the AL but not the plexi. I cant imagine a builder priming etc one side and not the other. But then I also wonder about having sika available but using screws exclusively instead.

Are you sure its really black Sika and not just black RTV that was used? Sika with primer and activator will never let go of the plexi short of grinding, though I suppose the primer could let go from the targa strip.....
 
Last edited:
Back
Top