Do you guys trust these things?


I was imagining that one guy would lay inside the hatch and support it, while another (or two) outside could guide the glass into place.

Given the stiffness and quantity of polyurethane used, I'm not expecting it to squeeze out. In the Sika documentation they strongly recommend using a triangular bead to avoid trapped air. The point of the triangle should compress down evenly as the glass is applied, and settle to a 'square' bead (or so they claim). With a windshield replacement, I'm guessing that the pinch weld would ultimately limit how deep the glass could go.


That's a good question. For windshield replacement, they would have a good amount of old urethane bonded near the pinch weld. I can imagine that to remove this would be time consuming and cause more problems (damage to paint, etc) than it would solve - since the polyurethane bonds so strongly to itself anyway.

I'm not worried about scratching the frame (pretty scratched up from cutting out glass already), but I am worried about using a compatible paint on the frame.

 

Sika training manual link
http://usa.sika.com/en/automotive/au...e/AGR-TTM.html

Excerpt:

 

This is taking longer than I thought (stripped screws in the frame, being super thorough in cleaning the glass). But I'm close to the final adhesive-and-seal step.

To answer the question about where to put the glass on the frame: from what I can tell the frame is going to need to sit high up on the frame with a minimal gap, if any, at the top. This will leave a significant gap at the bottom, which is required to clear the screw holes in the frame needed to reattach the wing. You also don't want to completely seal the screw holes... I think I am going to take some wood dowels, wrap them in teflon tape, and insert them in the frame wing holes before sealing. The dowels will hopefully also serve to support the glass within the frame to get the spacing right. I'm not going to clamp, just let the weight of the glass seat itself.

In terms of frame prep- for normal windshield replacement they do recommend leaving a small amount of urethane on the body for the new stuff to adhere to. That said, my removal job (putty knife, rubber mallet, and heat gun) left a pretty banged up "bead". So I stripped the frame sealing surface down to bare aluminum with a dremel and several sanding heads. I will prime the bare aluminum before sealing. I got comfortable with this approach since it mirrors the "Complete Adhesive Removal" (3.5) and "Aluminum Pinchweld" (3.7) sections of the Sika AGR technician's manual.

KVDR: there is a "gasket" below the hinge plates. Part number is 944-512-413.

 

Thanks for the part number! I suppose the gasket is necessary as a barrier between the aluminum frame and the steel body - preventing galvanic corrosion. I'll probably just make one out of some gasket material I have laying around.

What type of primer are you using on the frame? I read somewhere in the Sika manual that 'etching primer' should be used on aluminum. I'm planning on using urethane based paint for the frame, which should be compatible rather than acrylic which is water based and likely isn't compatible.

 

Someone mentioned using short lengths of drinking straws to keep the holes clear.

Edit - Also, thanks for taking the lead on this Sika Titan P2G re-seal. I think my schedule will conveniently lag yours, so please share all the lessons learned!

 

If I understand Sika Primer 206 p+6 is good for metals.

 

Yeah, the Sika Primer is the way to go. Per it's datasheet, it's 'Solvent-based polyurethane solution'.

 

No problem. Any thin gasket material should be a fine replacement for the stock material. I'm using the Sika 207 primer.

Oh, and as for moving the glass around- I bought two of these from Harbor Freight, and they've worked great. I used them to take the glass off the car, as well as flip it over a couple of times on the stand. http://www.harborfreight.com/aluminu...ter-92825.html

 

This is a great thread. One of these days I will fight my better sense and tackle this. lol

 

I just wanted to re-seal the top portion that always separates so I could use the struts and not have any leaks. I tried window weld and dow u- 428, both failed after one week. Did some researching and came up with LoctitePL Fast grab construction adhesive and its been holding for a couple months even with the very rough road conditions in my town. It only comes in a dull grayish color, but at this point I don't care, I can paint later if needs be.


http://www.loctiteproducts.com/p/pl_...n-Adhesive.htm

 

Anyone use Dow 428?

 

I had typo, dow 428 is what I used. It was better than window weld, but still failed. Stupidest hatch design ever!

 

Well the 3m failed so now I'm trying Dow 428. but this is only in the left hinge area!!

 

Made some more progress today - removed 99% of the old seal off the frame.

I started out with a heat gun and knife but quickly graduated to something more brutal.



Probably for the best - there was some hidden corrosion around the trim holes.

I'll clean up the remaining 1% with a dremel or knife, then light sand, etching primer, and hopefully a compatible paint.

Here's a pic of the tool I made last week for the weird screws

 

KVDR,

Why not leave the old urethane so the new urethane can bond to it? Isn't that what Sika recommends?

I'm going to use the Sika Primer 206 P+G (207 can work here too I think) on any bare metal. I know the Sika Titan (cold applied) product does not need a primer for glass, but I wonder if will still work if I prime the glass with the 206 like you would if you were using the hot applied urethane from Sika. I want to use the primer on the glass to get that OEM black paint look back.

by the way your screw tool is exactly the same I the one I have made - good thinking!!