Has anyone experienced major failure on Evercoats G2 or Slicksand polyester? Did a restoration in 2008 and didnt show any sign of problems til 2011. Looked like blistering. Or water droplets after a light rain. Topcoat was black in color, Akzo Nobel products used on everythng but the poly. Stripped and redid the restoration and am convinced the problem was in the polyester. Tore down this vehicle and did body parts piece by piece at different times and stages but had the same result on every panel on the initial resto. ON the redo found that adhesion was good, there was some corrosion in areas but clean in others. Did not seem to be a factor. Followed Evercoats directions as always. Contacted Evercoat and not getting much in way of an answer. User error of coarse. Anyone got an idea?
Ok did the car sit for any period of time (days or weeks not hours) after the poly was applied and before any type of sealer or top coat was applied?
I've had a similiar problem with their system. I used evercoat products and have some blistering in a black paint job also.
started the resto in january and finished in march. Dont believe the air was too wet. Also have a Kaeser rotarty compressor. I would say that the panels may have been exposed for possibly a couple weeks tops. Cannot remember exact timeline. Did the resto the same as many I have done.. same processes.
yes blisters were down to the metal but the only thing that looked like possible corrosion was small rings below the blister..not specific to all blistering .. was here and there.. looked more like corrosion you would see on aluminum...
Well could be that if the poly was left sitting without a top coat it may have absorbed moisture. Poly primers are talc based and absorb moisture like a spoonge. May have been extra humid during the time you did this one. Another possibility is old hardener. The MEKP hardeners break down over time and do so even faster if exposed to UV so if you have old hardener, even if you put the right amount as recommended, you are still undercatalyzing the primer. This makes it unstable and it will move with changes in temperature and dark colors make these fluctuations worse. Having said that the thing that kind of sounds weird is if it only bubbled like water droplets that sounds more to me like some kind of contamination under the paint not a product failure. Usually when polyesters fail it is in larger areas due to the factors I mentioned above.
We had some problems with a few jobs; the instructions used to say bare metal was fine but check the can, they no longer do. I asked a rep about it and he sorta stuttered when I grilled him. In the back of my mind I wonder if one of those all-overs from 5 years ago might not come back to haunt us.
I had the same issue with Slick Sand over a fiberglass car. It looked like tiny blisters, but only over the metal windshield frame, not over any firgerglass. I sanded it off the metal then shot a sealed and continued on.
Bare metal is fine if done properly. It gets done all the time up here with no problems but we have very low humidity in the air. The problem is, as I mentioned in an earlier post, that guys would spray the car and then leave it with no top coat for long periods of time and the primer would absorb mositure and fail. This is not really a product failure but a lack of understanding about how polyester primers need to be used. The new label suggest epoxy or etch now to combat this problem.
It is pretty arid here during the winter.. Had a U-Pol rep here and said the instant he looked at it that the problem was the hardener. I have no idea how old it was but our storage area is without sunlight. Got a number of restos out there and nervous about the outcome.
The problem with the hardener is usually from the paint store end. They often throw it all in one box and grab it as needed and if they refresh stock fairly often hardeners can sit on the bottom of the box for quite a while until they get low and then some poor sucker gets the old hardener. Or they don't rotate their stock and one case sits on the shelf forever and when they get low they finally dig it out and sell it.The good thing is if it is hardener it is likely a one time type deal. You can always check your hardener dates by the batch code that is on the crimped end of the tube. There will be a 6 digit number on it (can be hard to see but it is there). The first number is the year of manufacture and the second two are the month. Try and use hardener that is less that a year old. Same batch code system applies for the primer as well.
I believe the slick sand says you not supose to put it over bare metal, my buddy used it a while back and he said it said it was ok to put over bare metal, we got some and read the can and it said you not supose to put it on bare metal.
thanks for advice on the batch code.. didnt realize it had one.. I doubt I will be going back to any polyester.. have lost confidence in it
They are like any product they work when used correctly and can cause problems when they are not. No different than if you got a bad hardener with your topcoat or clear you would have a failure there as well.
Slick sand should always be put over a primer and it should never be wet sanded. It will absorb moisture that will come back to bite you.
True... Cant say that I dont make mistakes but I have seen nothing like this problem with my Sikken products and volumes of support from them compared to the Evercoat corp.
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