[67mach]

After taking in suggestions on seam sealing It looks like I screwed the thing up afterall.

I have my cowl painted with two good coats of corroless and my engine compartment with Chassis Black. I then go over the seams, That have now been painted as well, and after about 15 seconds the corroless and the Chassis Black are lifting.

I do not know what to do. I was able to scrape the stuff off most of the seams except the cowl. The paint and seam sealer just wiped off. All around each hat is wrinkled bubbled seam sealer. Underneath what I did scrape off was wet paint? The seam sealer must have penetrated the corroless and Chassis Black. In some places I tried Por15 there was no lifting and no problems.

I had used some enamel primer in some areas not treated my the corroless and the chassis black just came off almost as fast as i put it on. The primer is stil there and still holding on strong.

What the heck did I do wrong? I used 3M brush on seam sealer. Directions did not warn about lifting. The Chassis black can did though. Can I just let the cowl dry and hope for the best? I know the answer is to remove the stuff and start over. But, where? I guess I could strip and go back with the POR15.

Confused, Pi$$ed, and quite frankly: buzzed from the fumes!

 

[Midlife]

I don't know how to help you, but you might have stumbled onto the only chemical that can remove Corolless!! Hmmm...most interesting. I would have thought Corolless was impervious to seal sealers, and that was what I was going to do!

 

[scottstang]

Here are my thoughts for what they are worth. The seam sealer should be applied over some sourt of primer material (self etching or epoxy). The seam sealer should never be applied to bare metal as it will eventually lift. When dry the seam sealer can be topcoated (chassis black). I believe that the corroless is a laquer based material and as such, something in the seam sealer must be loosening the corroless and causing it to lift. IMO I believe that you will be best to start from scratch. I think it would be a stretch to think that the lifted areas will settle and provide a tight seam.

Scott

 

[67mach]

The Por15 did not lift. Only the Chassis black and Corroless. The primer stayed behind also. I have been able to remove the stuff from the seams other than the cowl. Too many compound curves I will have to wait until the weekdend I think.

 

[67mach]

Sorry, I was refering to your unedited email. I even asked on this forum about seam sealer and corroless. Everyone said to paint first. Everyone except Charlie65_67. I may have to go and try to remove that stuff before it dries rock hard.

 

[67mach]

Scott, The stragest thing is that the seam sealer is wet underneath and has caused the corroless to turn wet too. As if it was freshly applied.

I have removed the seam sealer from the outer fender wells wiht out a problem the only problem I seem to be having is the cowl. The compound curves and such are making it difficult at best. However, I thinK I need to remove it before it sets. I believe the primer first seam seal then chassis black is the way to go.

Thanks.

Thomas

 

[67mach]

Scott, The stragest thing is that the seam sealer is wet underneath and has caused the corroless to turn wet too. As if it was freshly applied.

I have removed the seam sealer from the outer fender wells wiht out a problem the only problem I seem to be having is the cowl. The compound curves and such are making it difficult at best. However, I thinK I need to remove it before it sets. I believe the primer first seam seal then chassis black is the way to go.

Thanks.

Thomas

 

[Guest]

Corroless and chassis black are both lacquer based. You can remove them with a strong solvent to get back to base metal just to clean things up.

I would suggest using an epoxy primer over the corroless which would also act as an abrasion layer since it seems really easy to scratch the corroless. This is what I did and it worked out fine. The epoxy primer will act as a barrier layer and not let the solvents get to the corroless. If you are doing non-visable areas, you can just brush on the epoxy primer even though it is designed to spray. Use a disposable natural bristle brush. You can then coat with chassis black.

Note that you must follow the directions in the chassis black to prevent lifting if you do multiple coats. I've had to scrape off a bit myself.

 

[cobrajet]

Wow! I have been lucky with a coat of 3M Weld thru in the seam areas and POR15 on the rest and Used 3M caulk tube seam sealer and never had any problems this last weekend. I guess I should count my blessings!

 

[67mach]

I was up well past 11:00 last night scraping and wiping the seam sealer off. The only solvent I have is the PRE product from Eastwood. It did an alright job leaving much of the corrolless behind. I am going to walk away for a few days off and see how it all dries out.

Epoxy primer is on my list of things to purchase. Right now the problems are all in the cowl area and the outer fender well. It looks like Hell right now but, as you said, in hidden areas I can brush someting on if I need to.

The car is going to be a Daily Driver and as such I do have some coverup factor with undercoating. I just did not want to let all my work be wasted.

 

[scottstang]

Thomas,
I know this has been frustrating but, I believe you are now on the right path.

Good luck and if you have any questions, let me know.

Scott

 

[GypsyR]

I've used the white 3M sealer that comes in a caulk tube very successfully. After some recent sealer discussion I went back and inspected some 3 year old seams (LONG term project). The seams look great. Recently I went to get some more. They were out, but had the 3M sealer that comes in a quart can. I figured "what the hay-3M is 3M,right?" Wrong.This stuff is "slimy" and gray. I found it difficult to work with and that it cracked up after drying. Obviously very different stuff. I don't know about paint reactions because I removed what I had put down and threw the can away. I'll hold out til they restock the "white stuff" and pay more attention to what I'm buying. The white stuff seems compatible with all the varieties of paint I have used.

 

[67mach]

I think the brush on stuff I have is exactly what you are talking about. I also bought two tubes of fast and firm sealer in caulk tubes. The tube is white but I do not know what color the product is.

Reading all the mags and posts I was sure the brushable stuff would work. I guess I did not know chemical reactivity of the stuff to some paints.

90% has been removed. Last night I primed all areas of bare metal and will give it the weekend to dry. Once done I plan on using the caulk. I used it years ago on a floorpan and it seemed to turn out good.

Thanks for he information, and letting me know someone else has had a not so good experience with a 3M product. I am sure the product if a good one just not what I thought it would be.
\
Thanks

Thomas