[Dave Willis]

Anyone else using it?
I cleaned two panes with some a few weeks back to remove brick/render salt. Customer seems very happy but it scared the life out of me, I swear the glass was covered in minute scratches. Can it scratch?

[rosskesava]

In theory, no. In practise, it can do.

I could be wrong on this but most metals will oxidise to one degree or another and it's that oxide mixed with other impurities that can scratch because they are harder than the glass. Or something like that.

I've always used an acid to remove brick salts. i.e. patio cleaner. Wear rubber gloves, pour a small amount on a sponge, wipe over glass quickly and immediately rinse with plenty of water and chuck the sponge and gloves in a bucket of water.

[Dave Willis]

I tried everything I had in the van , Viakal, Killrock, Winsol, Unger Rubout then finally bronze wool. I've never found anything yet that works on bricksalt - maybe a can of patio cleaner will need to be stocked.

[martinw]

you may  try either sorbo or mdr with non scratch pads. had decent results with those.