How to get out stain or marks on sidewalk?

March 30, 2010 6:47 AM

How do you get reddish brown marks off sidewalk caused from the snowblower scraping along the concrete?

My husband accidentally scraped our sidewalk with the snowblower and now that the snow has melted we see reddish brown marks on the concrete. It doesn't seem to come out with anything. It looks like rust marks. Any ideas to get it out and make the sidewalk look normal again?

Thanks!

posted by lynnie-the-pooh to Home & Garden (6 answers total)

Yep, that's rust.

If muriatic acid (really just HCl) doesn't work, it's likely that nothing's going to.

Note that this is really nasty stuff. Either be willing to use the product exactly as directed, including renting the appropriate equipment if necessary, or get a professional to do it. I'm sure there are half a dozen power washing companies in your phone book who would love the $100 it would take to do this properly.
posted by valkyryn at 6:51 AM on March 30, 2010

There are things much less nasty that muriatic acid that can get rid of rust stains.

Zud cleanser contains oxalic acid (which removes rust) and is relatively mild.
posted by ShooBoo at 7:04 AM on March 30, 2010

Could you "sand" them off with a rock?
posted by pseudostrabismus at 7:38 AM on March 30, 2010

look in the cleaner iasle at the store for "barkeepers friend" its a powdered cleanser that contains oxalic acid. its affordable.
posted by subarctic_guy at 8:21 AM on March 30, 2010

Why do you care? It's the sidewalk.

Or is it the walkway going to the front door of your house?
posted by reddot at 11:10 AM on March 30, 2010

Powerwashing, in my experience, is darn near magical if the surface has been prepped with something to loosen whatever it is you want gone.

If you find yourself unable to remove it, you might try naval jelly. This ought to turn the rust a black color, if you would find that preferable.
posted by adipocere at 11:34 AM on March 30, 2010