Tried enamel hardener on some paint work I was doing today. Not Rustoleum, but another alkyd ename...the results should be the same I would expect. The weather here was a high of about 36* F, so it's not exactly ideal painting conditions. I mixed the hardener about 8-1 with the paint. The can recommends adding the hardener first, then the reducer...but I wasn't thinning it at all so I just added the hardener. The paint seems thinner with it in there. Definetly easier to apply. I used both a foam roller, and a regular bristle brush for areas I couldn't get a roller (I was painting the inside of the trunk of my car). One of the first things I noticed was waaaay more bubbles in the paint when I rolled it compared to using the paint straight out of the can. Brushing it on wasn't much different from the straight paint, but it was a little easier since it seems thinner. It seems to flow out ok...probably no better or worse than plain paint.

But here's the big difference--in this weather (even with a small heater running in there) my drying times have been measured in DAYS. It was taking about two days just to get where it wasn't tacky any more. With the hardener in it, after about 3 hours it was pretty well set up. I'm going to go check it again here in a minute, but the difference in drying time is pretty dramatic. I would think this would be a benefit for anyone working on this... My paint layers are also a *lot* thicker than what you guys are aiming for. I want coverage in one or two coats (it's just the trunk, it doesn't need to be mirror perfect). A thinner coat should dry hard very fast this way.

I'm still going to try this on a spare fender I have and see how it turns out. So far I'm pretty impressed. This might be the answer to getting the paint to harden without waiting 4 months