I just watched this video on how to remove mill scale from Hot Rolled Steel. The guy used concrete cleaning acid, soaked the steel for 15 minutes, and then rinsed the steel with water. The scale almost washes off. Has anybody tried this? http://www.youtube.com/watch?v=LsEQP3YjEcg
And fully stress relieved too! Wood bleach aka oxolic acid works pretty well at removing scale too but is not very fast acting.
Ive spilt Coca Cola on my hot rolled steel work bench and the next morning the area was bright steel. So a bath of coke is another, stupider option..
I used acid to clean up my hot rolled steel. I put the acid in a throw away turkey pan and put one bracket into as a test. For the first minute, nothing. Then it started to bubble and I though, "wow". Then it started to smoke and I thought "OH NO!" The acid was attacking the aluminum pan. I quickly removed the steel and poured the acid into a Rubbermaid storage bin and used that for the rest of the parts. It worked pretty good. Lesson learned...acid + steel + aluminum = really dangerous!
True but many steel service centers carry the pickled & oiled version that has no scale. Gauges lighter than 16 are not typical in hot rolled.
I use muriatic acid with good results. 3 to 1 (w/ water) works well and takes about 15 minutes. Pour back in a jug and re-use a few times. Use Rubbermaid type containers and caution.
The active agent in soda is phosphoric acid, diet or reg. It will dissolve the shell of an egg, over time. Just think what it does to your teeth and bones.