Removing Mill Scale from Plate

[skylarkguy]

That looks pretty good. Nice job!

 

[CNC Dan]

The nice thing about vinegar is no hazardous waste cnc.
In fact none of the associated garbage that goes along with any of the stronger acids.

Fair enough. You might try looking for stronger vinegar (200 grain vinegar) or the acid that is in vinegar.
Acetic acid, I think.

 

[Oliver1655]

Muratic acid is the dilute form of hydrochloric acid used to clean pool. While is is a great rust dissolver, you better rinse it well then oil or paint right away or it will rust right back up.

 

[downsizingnow48]

You might try looking for stronger vinegar (200 grain vinegar) or the acid that is in vinegar.

Didn't know about 20 percent vinegar (vs 5 percent grocery store vinegar). Will check around locally. Thanks!

 

[rsallen]

Could that be as simple as leaving an open pail out in the sun to evaporate off some water?

It's an honest question.

 

[downsizingnow48]

The stuff I am using is 5% acetic acid, 95% water. So evaporating the water would result in a stronger and more aggressive solution. The 20 percent (200 grain) vinegar is apparently sold as an organic weed killer in nurseries. On the other acid suggestions. I used to use muriatic (dilute hydrochloric) acid when we had a swimming pool in southern CA. It was pretty harsh stuff so don't want to use that. I have used phosphoric acid-based rust remover on old car suspension parts, it worked OK. I think I will get some as an experiment to see if it is better than vinegar on mill scale. The household vinegar is cheap though - $3 a gallon - and I don't mind waiting overnight for the relatively small amount of cleaning that I need to do.

 

[aczlan]

The 20% vinegar is usually listed as cleaning vinegar and is not much more expensive than regular vinegar.

Aaron Z

 

[Gary Fowler]

There is a produce called WEDAC which is specifically made for removal of rust and mill scale. It is a combination of phosphoric acid and a detergent. I have used it to remove iron contamination on stainless steel. Spray a diluted mixture, wait overnight and hose it off. Sometimes it takes a second treatment.
Best results is total immersion in a mixture of WEDAC and water and let it set till clean.
http://www.west-penetone.com/literature/1824.bul.pdf

 

[Egon]

The stuff Diary Farmers use to clean their milk lines and tanks usually contains phosphoric acid. Should be available at Farm Supply stores.

 

[weldermike]

Cool!