cleaning bricks

[coveforest]

Okay, so I'm in the process of building the dome and it seems that I forgot to clean a few bricks before the mortar was set. Now I'm worried it will 1) look unsightly, and more importantly 2) the mortar will fall off during a cooking session. Should I worry about this? I saw a thread about using muriatic acid to clean bricks, but I'm not very enthusiastic about using that stuff.

Suggestions/advice most appreciated.

Chris

[GianniFocaccia]

If you're careful, you can use an angle grinder to remove just the mortar while allowing the diamond blade to barely contact the brick. The mortar should come off like butter and you'll easily feel the denser brick below. Remember to wear a mask!

[ggoose]

I agree with John...use the grinder very carefully and you'll be done in a few minutes. Muriatic acid is nasty stuff.

gene

[david s]

If you use Muriatic acid, also known as Hydrochloric acid, it must be diluted, but don't go stronger than 10:1 A safer alternative is vinegar, but it will be less effective on mortar that is hard. Rinse off any acidic cleaners with water.

[OzOvenBuilder]

Originally Posted by david s

If you use Muriatic acid, also known as Hydrochloric acid, it must be diluted, but don't go stronger than 10:1 A safer alternative is vinegar, but it will be less effective on mortar that is hard. Rinse off any acidic cleaners with water.

I personally never go stonger than 20:1, usually between 15 & 20:1. The stronger the acid (depending on the masonry) the more likely it is to soak into the brick and stay within the structure. I've visited jobs that have gone so hard on the acid, you can actually smell it as you walk past, and that's after 6 months!

I always use a sponge and fresh water on the day of laying after it's dried a little, to remove the most obvious bits of mortar that have found their way onto the face of the brick. This makes it a whole lot easier when using the acid, as I've found 20:1 sufficient to remove the light 'film' of mortar smudge which is left from the sponging.

Make sure you wet down any bricks down BEFORE applying the diluted acid. This will also help the brick/masonry 'take up' moisture beforehand which reduces the likelihood of acid penetrating the brick. A good wash down with fresh water is also essential.