I'd first gain some experience with small batches. Also, if something goes wrong you haven't lost everything. And handling liters of concentrated lye is a serious hazard. I once lost my fingerprints for a week because of a few spilled drops.

Have some patience: that freshly evaporated stuff can be harsh! If there is any lye residu in it, it hasn't had time to react with CO2 in the air to sodium carbonate, so wash it or give it some time! This is not idle speculation, I'm speaking of experience.