This question already has an answer here:
So, after doing extensive research and youtubing on bicycle truing and wheel building, I decided to completely de-tension a rear wheel on one of my old bicycles and try bringing it back up to tension/round/true/dish.
But, I ended up taco-ing my rim pretty badly in my truing process and rounding two of the nipples. I guess my spokes were too tight or something. I was just turning, turning, and then boom, taco'ed. Now I know, I guess.
So, I detensioned all the spokes again to try and start over, except this time, I noticed my rim was physically deformed. it wobbles and is out of lateral true pretty badly with no spoke tension on it. I tried bending the rim back into shape, and got it slightly better, but I think it's as good as it's going to get.
I can't really follow any of the youtube or online tutorials now, since my relative tension between spokes is going to be very disparate because of the rim, and all those tutorials assume (rightly so), you have a good rim to begin with.
I was hoping someone could list a methodical way of bringing such a rim back into tension/true/round/dish-ness.