Clear was under activated am I in trouble?

Barry

Paint Fanatic
Staff member
In about the last week three different people sent me a post on another forum
About I under activated my clear and spray 4:1 instead of 2:1, all pointed out he was getting a bunch of white-wash answers and said I should get on and answer.
NO, don’t really care about that forum BUT I get this call very often and the question what do I do?

Without writing a book, I want people on my forum to understand what happens here.
SO short and sweet.

Depends on the quality of paint you are using but the majors with their good lines usually have the OH/NCO set up 1:1/110 to 1.15 meaning going by resin you are adding about 10 to 15% more ISO than needed as we know you cannot mix them all in to mate with a paint stick, all of SPI’s are in the 1:1:5 to 1.18 area.

Private label and lower grades is usually 1:.00 to .80 or .85 to save money and in this case used 29% solids clear.
So, what will happen in this guy’s case?

He has cut the life by half, so from 3 year to maybe a year or two-year life span.
He has hurt the UV protection because of the cut back in the activator, yes, we put UV in the clear but the aliphatic ISO'S also help with the UV’s.

Bird crap if not washed off soon can eat the clear as with industrial fallout or a simple soda spilling.
What would be the easiest way to save this without stripping? He could set in full sun for a week, wet sand and spray 2 to 4 coats of clear over it mixed the right way, the risk here is to soon and the second coat application of clear could bust off the first after driving time.
I could go on and on but this give you a general idea of why the OH/NCO is so important and you never want to sub activators.
 
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So it will harden OK (put in sun to harden faster), but the UV protection is compromised, correct? Doesn't sound all that bad, just spray more clear.
You got a call from me a few years ago when I accidentally substituted reducer for activator, now that was a mess. :oops:
 
set up your bench before spraying . paint/clear/acc in the center reducers to the right lacquer thinner to the left . i actually set up backwards because of where my cleanup area is . but you get the jest. when you start read your label then mix .
 
I was generous to give the low solids spot repair clear a 3 year life span.
 
One of the most common calls i get.

Now in defense of the ones that did this.
I have done it myself on a Saturday
Mixing clear and tech line rings.
I answer the phone and keep mixing but i don't multi task and next day figured out i activated the clear with reducer.
Its not just new guy that do this.
I get a lot of calls from shops, i was mixing paint and someone interrupted me, i sprayed the car and not sure activated the epoxy or primer or clear. Well we will know in morning and usually it turns out ok next day.
 
Harden yes fully cure never, a lot more factors involved.

One of the first thing any paint guy ever told me was adding more hardener does not make paint harder, it makes it take longer to dry. Its one of those things you hear when you are like 18 and never makes sense. Now, I know those days it was called hardener, now its being called activator, but its something that stuck with me and eventually comes out.
In this case, I would wonder (if that is actually true) that this paint is going to get hard, but it might end up reducing the window you have to buff.
 
This is done in some industries, by the paint company increasing the nco ratio. But limited and usually
Non buffing situations.
Risks here are bad conditions and say high humidity could see co2 gassing and impossible to buff.
What you were told was part of the story and i just feed you enough to answer your question. Not being a jerk but somethings should not be
Promoted without knowing the situation of what doing and given proper advice. There are people on here where over years have said
Add 25 or even 50% more activator.
But it was for a specific item and prefer its not brought up.

Edit.
Rereading this what i meant by not bring up was anyone i had told to do this over the years, nothing to do this this post witch is fine. Hope i did not come off the wrong way.
 
Outside of the over activating topic. Use Polar if you need product to dry faster. I love that stuff.
 
This happened to a friend of mine. I asked him to spray the front of a car for me because I didn't have time. He forgot to add the hardener to the euro clear. The clear never hardened and said it was "crappy material". I had to grind all the paint off and start fresh. I made sure he saw me use the exact same materials. He finally admitted he messed up.

I also mixed and matched clear and hardeners from different brands. I didn't want to open a new kit of clear just to spray the B pillar covers on one of my cars. A friend gave me some restoration shop clear he had no hardener for. I had some extra universal hardener I use to put in basecoats. I mixed that 2:1 and it hardened fine. It even cut and buffed just fine.
 
Worked with another painter once that painted a complete "peeler", ran it through the bake cycle like we always did, let it cool, went to untape it and it was fingerprinting bad. He asked me what would cause it and I suggested he mixed it wrong. He ran it through 3 more bake cycles, still the same. Then he asked me how to fix it and I said you have to get the clear off. He said he wasn't doing that, too much work. He put it back in the booth and cleared it again and the lucky SOB got away with it. If I would have tried that the paint gods would have had the car burst into flames or something:p Hate to see what that car looked like a year down the road.
 
Trust me, it was a very temporary getting away with it.
Once in sun it would be a matter of weeks.
 
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