Duplicolor Clear Still Soft After 2 Months

[Lunajammer]

I used Duplicolor primer, Duplicolor color coat and Duplicolor clear. The color coat sat in the dehydrator for three days before the clear coat was applied. That sat in the dehydrator for at least a week or two and two months later the paint is still soft and polishes to a bland sheen, not high gloss. Can still dent it with a fingernail. In 30 years of using that product, never had that happen. It was sprayed in a warm dry place. Any thoughts?

[Ace-Garageguy]

The circumstances would seem to indicate something wrong with the clear...like it's missing a critical ingredient.

        ( Alkyd-based paints, for example, require the presence of particular "driers" to function        correctly. https://www.goldstab.com/articles/types-of-driers-and-their-functions  )

Paints and Coatings based on alkyd or modified alkyd resins are common in today’s markets. These air drying systems require catalysts to accelerate the chemical reactions of the drying process, called "driers".

I'd apply some of the clear to a clean, inert substrate, like bare steel, and see if it dries hard...thus eliminating any possibility of weird interactions with the plastic or paint substrates on the model.

That should tell ya if the clear itself is "bad".

EDIT: A further step would be to pull up the TDS for the clear, which should be available online, and see what the chemical composition is. If the base is an alkyd resin, this applies, which should give an indication of what got left out of your batch.

https://patchamltd.com/wp-content/uploads/2020/05/Paint-Driers-2.pdf

Edited March 20, 2024 by Ace-Garageguy

[StevenGuthmiller]

On rare occasions I have had this happen with this clear, although maybe not to this extent.

I’ve just chalked it up to a bad can of clear and moved on.

In every case, the clear eventually hardened, but I know it’s not an optimal situation.

I’ve probably bought 30 or more cans of this clear over the past 10 years, and I’ve had these issues with only a couple of them.

 

 

 

 

Steve

[Lunajammer]

40 minutes ago, StevenGuthmiller said:

In every case, the clear eventually hardened, but I know it’s not an optimal situation.

Well, I guess that's not all bad. I'll hold off further polishing, maybe for the summer, to avoid adding a drying barrier. At $18 a can it's freakin' disappointing, especially since that usual hard as nails finish makes such a nice gloss.

1 hour ago, Ace-Garageguy said:

I'd apply some of the clear to a clean, inert substrate, like bare steel, and see if it dries hard...thus eliminating any possibility of weird interactions with the plastic or paint substrates on the model.

I'll still try this though.

[StevenGuthmiller]

4 hours ago, Lunajammer said:

Well, I guess that's not all bad. I'll hold off further polishing, maybe for the summer, to avoid adding a drying barrier. At $18 a can it's freakin' disappointing, especially since that usual hard as nails finish makes such a nice gloss.

Yeah, it's gotten expensive, but then again, what hasn't?

 

And in the end, I've had issues with bad paint with every brand of paint that I've ever used at some point.

Just the luck of the draw.

 

 

 

 

Steve

[DRIPTROIT 71]

This may not be relevant to your situation, but I have had this happen on a bad resin cab before. The resin wasn’t mixed properly(you could see the swirls throughout the cab) and the paint wouldn’t dry in a couple of spots. The paint and the improperly mixed resin reacted with each other somehow and the paint just would not dry. 

[bobss396]

Duplicolor has been doing odd things to me as well lately. The primer is still working well. Anything I have top coated, 3 hours in the dehydrator and I'm ready to color sand. Like others, I suspect that there is something is funky with the clear.

[Lunajammer]

It's imperative that I do a follow up here nearly a year later.

This sat in my hot/cold attic since last March. Throughout, I checked the paint and it remained soft enough to dent with a fingernail, even up to today, but less so than a year ago. I decided to go ahead and sand/polish anyway and I was astonished to get what is probably one of the best glossy finishes I've ever achieved. 

Possibly because it was not rock hard, the sandpaper cut it easily and polish smoothed it evenly. After light sanding, each area got a vigorous rub only twice over and this was my result 😃. I don't know what to think about this anymore.