Stone Masonry

walhondingnashua

Burning Hunk
Jul 23, 2016
212
ohio
I am doing my second stone project. First was a small river stone wall behind my wood stove and I just used grout between the stones. It was actually more like a tile job, so I had more experience. This job is a stone retaining wall made from old road blocks from the city of cleveland. All granite or sandstone. I am not very "clean" about it, and have mortar all over my stones when I am done. I have read that muratic acid is the way to go to clean it when I am done. Is this correct or is there a better way? I really just don't know how I could keep it any cleaner and actually do a good job.
 

bholler

Chimney sweep
Staff member
Jan 14, 2014
20,167
central pa
I am doing my second stone project. First was a small river stone wall behind my wood stove and I just used grout between the stones. It was actually more like a tile job, so I had more experience. This job is a stone retaining wall made from old road blocks from the city of cleveland. All granite or sandstone. I am not very "clean" about it, and have mortar all over my stones when I am done. I have read that muratic acid is the way to go to clean it when I am done. Is this correct or is there a better way? I really just don't know how I could keep it any cleaner and actually do a good job.
Yes muriatic acid will take the mortar off but it may also discolor or damage the stone.

What type of mortar are you using and how wet is it?
 

walhondingnashua

Burning Hunk
Jul 23, 2016
212
ohio
Yes muriatic acid will take the mortar off but it may also discolor or damage the stone.

What type of mortar are you using and how wet is it?
Just 60lb bags of quickcrete mortar mix. I am trying to keep it as dry as possible but still useable. The more I do the less mess I make but it still ends up on the stone. If I just clean the entire wall face with the acid, would the color change still be pretty even then?
 

bholler

Chimney sweep
Staff member
Jan 14, 2014
20,167
central pa
Just 60lb bags of quickcrete mortar mix. I am trying to keep it as dry as possible but still useable. The more I do the less mess I make but it still ends up on the stone. If I just clean the entire wall face with the acid, would the color change still be pretty even then?
Yeah bagged mortar like that is a real pain to work with. You have to add allot of acrylic modifier to make it workable. How are you striking your joints? Are you cutting and brushing it to soon so the mortar joints are smearing onto the stone? Or brushing to late so the mortar has set up to much and won't brush off?
 

walhondingnashua

Burning Hunk
Jul 23, 2016
212
ohio
I think I am brushing to soon, especially with the first 10 or so stones I did. I am getting better but in the process of working mortar between everything, I still end up with some on it. If I know I can use the muriatic acid, I can at least clean it up when I am done.
 

bholler

Chimney sweep
Staff member
Jan 14, 2014
20,167
central pa
I think I am brushing to soon, especially with the first 10 or so stones I did. I am getting better but in the process of working mortar between everything, I still end up with some on it. If I know I can use the muriatic acid, I can at least clean it up when I am done.
I don't know what it will do to your stone. You just have to test a couple spots.

You really shouldn't be working much between the stones after they are set. Just a little pointing on the surface of the joint. Which you do by scraping some off your trowel onto whatever striker you are using then push it into the joint with that.
 

walhondingnashua

Burning Hunk
Jul 23, 2016
212
ohio
There is a learning curve with this that I am picking up on. By the time I am done, it might be ok.
None of the stones are consistent so there’s a lot of piecing together and mortar.
 

shortys7777

Burning Hunk
Nov 15, 2017
193
Smithfield, RI
sponge and water bucket. Rinse often. Work is small sections. I do this with wall cap joints in the summer but I use sand and portland cement mixed. Wipes up pretty easily even when its almost dry.
 

bholler

Chimney sweep
Staff member
Jan 14, 2014
20,167
central pa
sponge and water bucket. Rinse often. Work is small sections. I do this with wall cap joints in the summer but I use sand and portland cement mixed. Wipes up pretty easily even when its almost dry.
That may work ok for wall caps but would make a huge mess out of a wall like his. And you should not have used straight Portland to mix your mortar. It will be to hard. You should have used probably type s mortar mixed with sand instead.
 

bholler

Chimney sweep
Staff member
Jan 14, 2014
20,167
central pa
Type S is the kind we use.
Oh ok good. Typically when someone says Portland they are referring to straight Portland which should not be used for mortar. Cement for mortar is a blend of Portland and other things mainly lime in specific proportions.