Re: Is paint catalyst optional ?
All a catalyst does is speed up the process of degradation of the inhibitors in the paint. Thus why people call it hardener, which isn't the proper term. If you want it to cure faster use the catalyst. For some paints like awlcraft and awlgrip, and you are brushing it they have certain reducers and catalysts that are slower than the spraying versions. This allows the paint to "lay out" better to allow the brush lines to settle smooth.
My family owns and operates a marina and boatyard. I have painted boats, masts, cars.. My advice to you, use the catalyst. If your in the northern hemisphere, it's winter now, it's cooler than normal so it takes even two part paints longer to cure, so I'd use the catalyst. If you don't want to wait for it to cure over the course of a few days to a week, I'd use the catalyst. If it's there and all you have to do it mix it, I'd use it.
Any two part paint will get hard over time, usually it's uv that breaks down the inhibitors (same goes for resin and epoxy) but it takes a lot longer.
-sent from sea via corked bottle