Sand/Media blasting brick walls

[Rfreeman]

Just wondering has anyone ever tried sand/media blasting old (20+ years) bay walls to get them clean?

My guys and I are cleaning up the most recent purchase and we are using straight acid and HP water cannon (3500 PSI) to clean the brick and it's doing the job BUT my guys seem to think we could blast it off a lot quicker....????

We are about to start Monday so if someone has tried it let me know or if I'm about to make some fatal mistake let me know.

 

[MEP001]

I've seen the result. I can take some pictures. The brick ends up looking terrible. One was blasted because it was dirty, the other because it had been painted every few years for decades.

 

[Rfreeman]

Please do bc sounds like this isn't going to be a good idea and we did one bay on Friday with acid that came out great

 

[OurTown]

Are you going to put some kind of sealer on them when finished? I'm curious as to what type would hold up.

 

[MEP001]

I drive past a wash a couple times a month where they put some kind of sealer on the brick after they cleaned it. I don't know what they used, but it's holding up well. It's doing nothing to keep the walls clean.

 

[Rfreeman]

Well I'm rethinking the whole idea now. The last thing I want to do is ruin the brick or create microscopic pores for dirt and grim to get into and dirty the place up faster.

The acid is cleaning the walls great its just take more time than usual and I told my guys its bc its been 20 yrs. since they did anything (which is true)

Here are the pics....posted in another thread but I didn't want to hijack the topic there so I started a new one.

 

[MEP001]

Even if blasting doesn't make it porous (and I'm pretty sure it does), it'll remove a lot of the character from the variance in color. That wall looks really good. FWIW I've been brushing the acid on instead of spraying it, so there's a lot less waste. It's not difficult and doesn't take much longer.

 

[OurTown]

It's doing nothing to keep the walls clean.
[/QUOTE

Wouldn't they be easier to clean next time?

 

[MEP001]

Possibly, but I think the idea of the sealer was to keep the walls clean. It doesn't. It's also kind of weird-looking for the brick to have a gloss to it.

 

[Rfreeman]

Yeah my guys are using paint rollers to really soak the walls in acid and let them sit for a couple of minutes before hitting them with the HP.

As of now we have 3 bays down 3 more to go.