Pointing front steps muriatic or sulfamic acid?

[vdotmatrix]

Every year I have to re-do this &*^%*^$ project.

This year when I tear up the front steps again with my air chisel and clean all the affected surfaces. what should I clean the surfaces before I mortar? muriamic or sulfamic acid?

It's sometimes better to be lucky than smart.

[HayZee518]

Muriatic acid is dilute hydrochloric acid the other stuff you mention is sulphuric acid base diluted. Muriatic seems best.

[vdotmatrix]

I am a chemist not a mason. are these acids typically used routinely for this purpose.

It's sometimes better to be lucky than smart.

[HayZee518]

yup