Enclosure painting. More questions about weather/humidity.

[EBK]

And, if you are as fortunate as I am, once it's dry to the touch, you can gently sand off the parts of our natural world that decided to disrespect your "wet paint" sign before resuming.

[EBK]

Maybe this comes down to understanding whether different types of finishes are more accurately described as "drying" or "curing".  Someone other than me can transform that notion from mush into actual information, perhaps.   

Regardless, I have an enclosure in the finishing process right now that simply must be finished, humidity be damned.  I'll try being extra thin and delicate with my dust coats, and if it doesn't work out, then I'll figure out how I can redo it the "right way" (there is a TechShop near me that I've been itching to try out...).

[PRR]

Google "paint humidity" brings up lots of stuff.

Some of it is crap.

Beware the (at least) two kinds of paints. Water-base and solvent-base. Water-base just cures more slowly in damp. Solvent-base is actively contaminated by damp air.

Hot-Rod forums are reliably solvent-base guys, but they also get into various additives and reducers to control viscosity and dry-time. Apparently a seasoned car-sprayer can work in humidity that I would not want to attempt.

Large cardboard box with a heat-source (lamp that will NOT set the box on fire). For the same % actual water in the air, higher temp means lower RH, and high RH is apparently the problem. If the air is holding the water well (low RH), it is less likely to damp your work. High temp also means faster solvent dry-out. Good to a point, but we all know of over-baking a several-layer job and the undercoats bubbling the overcoat off.

[slashandburn]

Thanks everyone.  Paul is hitting on what's been bothering me.

>>>>  Solvent-base is actively contaminated by damp air.

>>>>  Apparently a seasoned car-sprayer can work in humidity that I would not want to attempt.

So assuming you mean you'd generally avoid working in high RH, how high is too high? 

Would the biggest risk contamination happen while spraying or while the painted object sits to dry?   Placing an enclosure near a dehumidifier to dry, or in a hot oven where water evaporates quicker all sounds good  but if I'm spraying in a garden shed on a humid day, is the bulk of the contamination already done by the time i spray and get it into better drying conditions?

Cheers to the rest of you too. I've picked up a fair few more painting tips here. Do you all really manage with such few thin coats of clear?  Can you really give it a polish without rubbing through the lacquer?

[EBK]

Cheers to the rest of you too. I've picked up a fair few more painting tips here. Do you all really manage with such few thin coats of clear?  Can you really give it a polish without rubbing through the lacquer?

I sincerely hope that you're learning from the others and that I didn't give you the impression that I'm personally any good at this!