I saw this reddit post where people said BKF was fine but that doesn't match what I'm seeing. I just bought a new wok which I was about to season. It had a coating of oil/grease. I washed it with dish soap and then wiped it with a paper towel. The towel became very very slightly dirty  So I thought I'd wash it again. I had just got a bottle of BKF and thought, "oh, perfect chance to try this!". I washed it with BKF and immediately it started to turn rust colored. Wiping looked like this  So I washed it 2 more times with dish soap but the rush just keeps coming  You can see the wok in the back of that picture is all yellowed. There was zero yellow after the first wash, before using BKF Here is what it looked like just after that last picture   And here it is close up 10 minutes later   The advice in that reddit post is to scrub even more with BKF to remove the rust but AFAICT it was the BKF that made it rust so using more is going to make more rust not wash it off. Have I ruined this wok? I'm afraid to cook with it and get rust in my food. Should I have not used BKF on carbon steel? I have 2 carbon steel frying pans and a smaller carbon steel wok. I've never used BFK (or even soap) on those. Once seasoned I just kept them clean with water, scrubbers, and then oiling them with heat. I was planning to do the same with this wok and then this rust thing happened. Woks aren't expensive so no worries if I need to discard it but a little freaked out about BKF induced rust.  Update: Given it's already covered in rust I washed it 3 more times with BKF. Every time, seconds after I finish rust forms again. Rinsing off the BKF and wiping I get a paper towel full of rust.  Update 2: Here's video of me trying to wash it. Before I can clean 1/2 of one side of the wok it's already rusted again https://www.youtube.com/watch?v=hlXgrOmOWEg 
Definitely not ruined. When I had to completely redo the seasoning on my wok a few months ago I had something similar happen. The issue I determined was just that the wok was staying wet too long. Paper towels are only so absorptive, and then moving the same damp one around gives the metal even more opportunity to oxidize. You can use a manual abrasive (like a green pots and pans scrubber instead of the blue sponge) just to scrape off rust and rinse as quickly as possible before drying it and putting it on the heat. Once being heated, grab a new dish towel and dry the inside even more, then go for the oil. Prior to oil, and once the wok is hot/warm and dry, you can also use a mild dry abrasive like baking soda or salt and a dry towel to polish off any new rust. THAT SAID - you do need to oil it while it's hot if you go this route. Mine rusted again when I tried to take a break before seasoning lol. That said, don't worry too too much if you still see a tiny bit of orange or grey prior to seasoning. Because once you have seasoned it, that surface with whatever miniscule traces of rust will be sealed under the layer of polymerized oil. It won't get in your food as long as the wok is seasoned well. 