Can you please explain, for lil O'me?
2 part urethane finishes are quite common for the pro sprayers with guns. It involves 1 park urethane and 1 part hardening agent (
example). The proper mix is important, and to get it as you desire usually takes a fair amount if trial and error. It is harder to clean equipment after use than with one part poly, but has major advantages. It is sandable in 24-72 hours (depending on conditions and how much is sprayed) and it results in a harder, more scratch resistant surface. It is also less prone to runs and flattens out nicely .
This rattle can makes 2K spray available to those of us without spray guns and booths. It has a diaphragm with the hardener inside the can at the base, which is released by taking the red plunger off the cap and pushing it in to the insert on the bottom, thus allowing the perfect mix of urethane and hardener just when you need it.
CONS:
- It has catalyzed urethanes. This is highly toxic and can cause cancer. It can be absorbed through the skin. Long sleeves, rubber gloves and a proper respirator are mandatory. I also use a shower cap and goggles.
- it is more expensive ($20 per can).
- It is no good 24 hours after mixing, so if you don't use the whole can, or you want to open another can for just a few more sprays, it is wasteful, especially given the expense.
For me, it is worth the cons. The results, time savings and scratch resistance are a huge benefit. Also, less risk of burn through when finish sanding