Thursday, March 29, 2012

Should I Remove Rust Spots and Other Questions.

Ask a Pro

  Q. -  I am going to try the Concrete Camouflage artistic grade stain and have some questions.
I just pressure washed the driveway today to get any dirt or mildew out of the pores of the cement and it is looking very clean now. Will I have to do this again or any other additional cleaning before putting the stain on when it gets here I would hope early next week?
Hello Robert,
   A. -  As long as the concrete is still clean, then it should be fine to stain without further cleaning.

Should it be completely dry when I do stain it?
   A. -  Yes, the concrete should be dry when applying the stain. It doesn't have to be bone dry though, just dry.

  Q. -  I saw in an earlier blog post that you told someone not to worry about a small rust stain. I have a few rust stains that I can't pressure wash out that are probably 6" to 12" diameter sections. Will these most likely be covered/hidden by the stain as well?
   A. -  That depends on the color of stain that you're using, but yes, the stain should help to camouflage the rust spots quite a bit. The browns, blacks, riverstone, and many times even the reds work well. Yet the turquoise, greens, and lighter colors have a harder time. That's why you should do some tests first if you can.

  Q. -  If I do decide or need to try to clean them, will CLR or lime away affect how the stain in absorbed in these areas after I use it? I only ask this since I know the stain reacts with the calcium in the concrete.
   A. -  It is true that the stain reacts with the lime and other minerals in the concrete. Anything adversely effecting the existing lime and minerals in the concrete will diminish the stains capacity to work. That's why standard grade stains will no longer work on acid washed concrete and even artist grade stains don't work as well as they would have.
   Besides that, any such harsh cleaning would almost certainly leave an area that is discolored from the rest of the concrete. Even if it did work to take out the rust stain, you would likely be left with a bleached out spot. The spot would then stain differently from the rest of the concrete, so you would only be trading one type of blemish for another, and working hard to do it.
   Of course you could do a highlighting coat to help further camouflage the spots. You could stain the entire area with a light or medium color. Then after it dries, you can do a highlighting coat with a darker color. That would help the rust spots to become part of the character of the concrete, rather than blemishes.

  Q. -  Should I dilute your artist grade stain? I have read on many sites that most people at least dilute acid stains 1:1 with water.
   A. -  All Concrete Camouflage products are designed to be used straight out of the bottle.
   However, if you prefer to dilute the stain 1:1 and then do a two coat application, rather than using it straight and doing a one coat, then that's fine too. Many contractors do it that way still. So they can spray and brush the first coat, allow it to dry, and then spray only the second coat.