POR on windshield frame
Thread Starter
Le Mans Master
Joined: Oct 2004
Posts: 5,269
Likes: 54
From: Orlando Florida
St. Jude Donor '05
POR on windshield frame
About six months ago I painted my windshield frame with POR15. I wire-brushed the surface rust and then applied their cleaner/metal ready/etching primer per their instructions. The semi gloss black POR looked great....
Now, six months later my new windshield is cracked. It's a stress crack in the lower left corner and they replace the glass under warranty. The installer was supposed to be at my house last saturday but didn't show up to work..... another installer is scheduled for tomorrow, let's see if that guy shows up....
I removed the stainless trim pieces - I used RTV between the side pillar trim and the frame and yesterday I cut the RTV off the frame using a razor blade. The POR came off too
I was (and still am) very surprised how easy that stuff comes off the frame.... Once the glass is removed I'll more than likely hit the entire frame with a wire wheel, 40 grit sandpaper and use primer instead of the POR. I'm glad I only bought the starter kit and didn't paint the entire frame and suspension parts with that stuff - I'm not impressed at all with POR
Now, six months later my new windshield is cracked. It's a stress crack in the lower left corner and they replace the glass under warranty. The installer was supposed to be at my house last saturday but didn't show up to work..... another installer is scheduled for tomorrow, let's see if that guy shows up....
I removed the stainless trim pieces - I used RTV between the side pillar trim and the frame and yesterday I cut the RTV off the frame using a razor blade. The POR came off too
I was (and still am) very surprised how easy that stuff comes off the frame.... Once the glass is removed I'll more than likely hit the entire frame with a wire wheel, 40 grit sandpaper and use primer instead of the POR. I'm glad I only bought the starter kit and didn't paint the entire frame and suspension parts with that stuff - I'm not impressed at all with POR
Melting Slicks
Joined: Nov 2001
Posts: 2,668
Likes: 43
From: Eastern US XX
About six months ago I painted my windshield frame with POR15. I wire-brushed the surface rust and then applied their cleaner/metal ready/etching primer per their instructions. The semi gloss black POR looked great....
Now, six months later my new windshield is cracked. It's a stress crack in the lower left corner and they replace the glass under warranty. The installer was supposed to be at my house last saturday but didn't show up to work..... another installer is scheduled for tomorrow, let's see if that guy shows up....
I removed the stainless trim pieces - I used RTV between the side pillar trim and the frame and yesterday I cut the RTV off the frame using a razor blade. The POR came off too
I was (and still am) very surprised how easy that stuff comes off the frame.... Once the glass is removed I'll more than likely hit the entire frame with a wire wheel, 40 grit sandpaper and use primer instead of the POR. I'm glad I only bought the starter kit and didn't paint the entire frame and suspension parts with that stuff - I'm not impressed at all with POR
Now, six months later my new windshield is cracked. It's a stress crack in the lower left corner and they replace the glass under warranty. The installer was supposed to be at my house last saturday but didn't show up to work..... another installer is scheduled for tomorrow, let's see if that guy shows up....
I removed the stainless trim pieces - I used RTV between the side pillar trim and the frame and yesterday I cut the RTV off the frame using a razor blade. The POR came off too
I was (and still am) very surprised how easy that stuff comes off the frame.... Once the glass is removed I'll more than likely hit the entire frame with a wire wheel, 40 grit sandpaper and use primer instead of the POR. I'm glad I only bought the starter kit and didn't paint the entire frame and suspension parts with that stuff - I'm not impressed at all with POR
Get rid of ALL the RTV, scrape and wash down the area and re-coat with POR 15.
POR 15 is GREAT stuff - when used correctly - but it can be ugly if the surface is not properly prepared.
Last edited by pws69; Jan 19, 2007 at 11:39 AM.
Thread Starter
Le Mans Master
Joined: Oct 2004
Posts: 5,269
Likes: 54
From: Orlando Florida
St. Jude Donor '05
RTV is the ABSOLUTE WORST you could use on steel - particularly rusted steel. It creates a chemical reaction that actually CAUSES rust - I'm not surprised at all at the problems you are seeing.
Get rid of ALL the RTV, scrape and wash down the area and re-coat with POR 15.
POR 15 is GREAT stuff - when used correctly - but it can be ugly if the surface is not properly prepared.
Get rid of ALL the RTV, scrape and wash down the area and re-coat with POR 15.
POR 15 is GREAT stuff - when used correctly - but it can be ugly if the surface is not properly prepared.
I didn't use RTV on steel.
I painted the entire windshield frame with POR and it cured for a few month before I installed the trim with RTV. When I removed the stainless trim I found what appeared to be RTV between the trim and the frame, it 'felt' like the sticky stuff that is used to hold the water barrier foil on the doors....
I only applied a small bead of RTV, yet the POR was very easy to remove in areas where I did not apply RTV.
I believe POR just doesn't adhere to clean steel - a few forum members warned me about the poor (or should I say POR) adhesion to anything other than rusted steel..... I should have listened back then..... that stuff might be great on rust but on clean steel it just doesn't stick.
And RTV shouldn't weaken it at all, heck... on a frame that stuff has to withstand engine oil, grease, ATF and whatever else leaks ----> note: $5 spraycan engine enamel can handle most of the above mentioned fluids
NCM Grand Opening Veteran
Joined: Sep 2005
Posts: 20,979
Likes: 384
From: South of giving a damn
St. Jude Donor '11, '17
I don't want to sound like a jerk, but didn't you read the POR-15 instructions? They clearly state that POR-15 is not to be used on clean metal. If the metal is clean, then it must be treated with their Metal Ready (or other acid wash product) first. If you wire brushed to bare metal & made it look shiny then I wouldn't expect the product to stick. I wire brushed the loose stuff off of my WS frame & used POR-15 on it. Everything stuck fine. Encapsulators require a rougher surface, for adhesion.
Melting Slicks
Joined: Jul 2004
Posts: 2,577
Likes: 2
From: Long Island New York
I don't want to sound like a jerk, but didn't you read the POR-15 instructions? They clearly state that POR-15 is not to be used on clean metal. If the metal is clean, then it must be treated with their Metal Ready (or other acid wash product) first. If you wire brushed to bare metal & made it look shiny then I wouldn't expect the product to stick. I wire brushed the loose stuff off of my WS frame & used POR-15 on it. Everything stuck fine. Encapsulators require a rougher surface, for adhesion.
POR stands for Paint Over Rust.
Thread Starter
Le Mans Master
Joined: Oct 2004
Posts: 5,269
Likes: 54
From: Orlando Florida
St. Jude Donor '05
That is exactly what they say to do - they do not say that you can't use it on clean metal, they tell you to use their metal ready and that's it....
Now, the good news: there's no rust under the POR -
- I removed all the POR and applied primer instead 
If that glass guy shows up today I'll clean the rest of the frame (under the glass) as well...
NCM Grand Opening Veteran
Joined: Sep 2005
Posts: 20,979
Likes: 384
From: South of giving a damn
St. Jude Donor '11, '17
Well, if you used their metal ready & the POR still failed to adhere, then you have a reason to question the products worthiness. I don't know what to say other than if the instructions were followed, then I would try something different also.
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