How do you use muriatic acid to scratch out concrete?

Answer 1

If you are wanting to etch the concrete pryor to painting/staining, I suggest mixing the acid with four parts water to one part acid. then pour/spread solution over the whole area. if indoors, use fans, open windows, etc. to vent. if outside, hose down grass, plants, etc. around the concrete, to protect from acid. wait 5-10 minutes, while the acid works, scrubing any areas that are rally dirty. after 5 minutes or so, rinse repeatedly with a garden hose. make sure you use PLENTY of water, to completely nuetralize the acid. wait a week or so to let the concrete dry, and then paint away.

Answer 2

Muriatic will etch concrete surfaces. It's applied in a 3-5% strength, allowed to sit as long as needed (so long as it doesn't dry out) then rinsed off. It's usually applied with a pump-up plastic garden sprayer.

Note that the acid will damage anything else it gets on with the exception of plastics and a few other things. Grass, siding, clothing, etc. It will also injure skin, and in concentration releases noxious fumes. It can be neutralized by spreading a solution of baking soda and water over it after application just before rinsing to minimize damage from run off if needed.

Read warnings and instructions before starting!