Lacquer Drying Issue

I mistakenly mixed about 2 oz of pre-cat catalyst to a gallon of lacquer, 1/2 oz more than what was called for. It never occurred to me to simply add more lacquer. Anyway, my first coat of finish isn't drying as fast as normal... more than 2 hours and it's still slightly tacky. I sprayed late in the evening and the humidity has been at least 80%, today, so I'm assuming these conditions play a small part. Is too much catalyst the problem and will the finish dry over night. I'll correct the mix tomorrow.
Sonny
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Are you asking a question or simply commenting on the day's activities?
Robert
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wrote:

I was asking. Forgot the question mark. Is too much catalyst possibly the problem, also?
Sonny
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Strangely, it probably is. You would think that the catalyst would speed up the actual reaction and cause something like cracking or glazing. Maybe it is extreme conditions like doubling the catalyst. But the catalyst isn't a "hardener" like one finds in epoxy, nor is it an activator to change the chemical composition of the actual finish. According to the wonks at SW, when you mix the catalyst into the base, you are actually creating an entirely new product.
Being interested in so many things that are mundane and sometime quite pointless, I actually went to a 4 hour class on using cat lacquers that was put on by the Sherwin Williams Industrial Coatings Division.
The only one I have used is SW. SW was completely specific about the mixing of their product, and advised using measuring cups for the catalyst, and only mixing in gallon batches as anything less than a gallon could produce an unreliable or strangely performing product. Since their product lasts well even after mixing, it made sense.
I would personally think that mixing in the exact percentages, regardless of volume would result in the same end product, but they say no.
The point is this; when you over catalyzed the product, you made you own product, not one that performs to the manufacturer's intention. For precats, adding too much catalyst will actually make the product dry slowly, and possibly corrupt your finish. Until understanding that the process that adding catalyst created a new product (as opposed to modifying an old one as one does when they add thinner to paint), I thought adding more catalyst would speed the process up like when you add too much hardener to epoxy.
Not so, says the company rep. Since I like using really "hot" finishes and spray quickly, I am always open to speeding things up. I **specifically** asked if more catalyst would speed things up. The SW rep **specifically** told me that fooling with the mix was a recipe for disaster and also told me that adding too much catalyst and under mixing were the two most common culprits in precat problems.
I probably learned the most at the seminar/class in the trouble shooting portion of using the product. According to the SW guy, too much catalyst can actually get your end product to the point where it will not harden! It will dry to some extent, but will have an oily feel to it, and even then it might take a couple of days to get to that. This was part of the "troubleshooting" portion of the class. It will dry too soft, which defeats the reasons (hardness and abrasion resistance) we use precats. It may also sag, or even pool. Or is could go the other way and craze when drying. Also, with too much catalyst it was pointed out that the final finish may not be 100% stable for a couple of weeks... maybe more. Remember, there is a big difference in any finish between "dry" and "stable".
Take that for what it is worth. This was one corporate man speaking about the SW product to a bunch of finishers that was wanting to make sure we followed ALL directions perfectly so we wouldn't blame anything on his product if it wasn't satisfactory.
If I were you, I would call the technical help line usually found on the can (or internet) and talk to one of their industrial coating specialists. It won't be the same guys that answer for consumer goods, and some of those guys are really sharp and you have to know you certainly won't be the first one (or even 10,000 th) guy to do that. They will have instructions specific to their product on how to handle this. A quick call to one of my fellow sprayers here was answered with his opinion being that you will need to remove the existing finish and start over again.
Do me a favor, Sonny. I don't use precats because I don't have anyone calling for them, but I am always interested in how things turn out in finishing. There is no end to the learning process in finishing..... none. We all get better, but no one knows all of it.
If you call their tech line, please share with all of us exactly what you find out, how they tell you to correct the problem (in detail please) and who the manufacturer of your product is, and if they were helpful on the phone.

Robert
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