wet sand blasting

[snagtooth]

Wet Sand Blasting with their pressure washer: Who's doing it/done it? What kind of medium did you use? Any tips or pointers?

I purchased a wet sand blast kit from GP for a specific project. I have a home depot Behr one part epoxy that a maintenance guy applied outside on the entry sidewalks of a hotel. Within two weeks the epoxy was popping and flaking everywhere. The issue stems from moisture trying to leave the slab, moisture from underneath causes "non breathable" membranes to pop and flake off. So as a remedy I am going to be removing the epoxy and applying a tinted, breathable color stain. I received the sand blast kit and played with it a little today with a medium of 40/60 mesh size, seemed to be really aggressive. I don't want to ruff up the concrete too bad, so wondering if anyone has any tips, pointers, experience with a project similar to this. Thanks.
-Cal

 

[midatlanticpower]

The worse part about using that sand blast attachment is when lean the nozzle at an angle the water runs back down and clogs the sand up. It takes alot of time and you have to pick up all the sand. Have you tried a stripper and hot water?

 

[snagtooth]

Have you tried a stripper and hot water?

I know it's going to be a mess and a pain in the ass, haven't tried a stripper. Already hit it with a general hot water and degreaser clean, some of it came up, most didn't. What kind of a stripper are you thinking?

 

[midatlanticpower]

You need Caustic stripper. Something thick that you brush on. We use stuff from Sherwin Williams called Dads Stripper. They also sell some similar stuff at HD. Let it sit on fit half hour or so and then blast off. You might have to reapply a couple times. Burns like hell. Be careful. Use a metal container and brushes that you can throw away when your done.

 

[snagtooth]

Let it sit on fit half hour or so and then blast off.

I think I would rather have sand everywhere than caustic stripper to deal with. This is the front entry of a hotel, windows, front door traffic, drivethru unload area, etc. Cant have people tracking caustic all over. I am planning on building a plastic barrier wall on at least one side but sounds like a liability.

 

[palm beach]

Less liabilty with stripper than blastin sand and water all over. Use surface cleaner. .do you have reclaim..either way you need to quarantine off your work area..buy some test it out same as you did with the s.b kit

 

[ABC]

Saw a couple of Germans wet sandblasting in Hamburg just the other day. Seemed pretty effective. It was the first time I had seen this type of cleaning. Effective but messy.
Esp. on an urban area by the rails station.

 

[snagtooth]

Randy over at Shasta Pressure Clean was kind enough to reach out to me and gave me some great pointers and suggestions over the phone yesterday. Im starting tomorrow, going to try a few differnt techniques including a stripper and some pressure washing/sand blasting, sand at last resort. Randy was very knowledgeable about "restoration" of concrete surfaces, gave me some confidence to tackle this project. Thanks for the input everyone, thanks Randy. Ill post some pics as I proceed.

 

[snagtooth]

Chemical Stripping

Ok. Day one, only got 500 sqft removed and prep'd. Here are some pics. I went with a chemical stripper from Sherwin Williams called Superstrip. Squegeed/brushed it out and vac-surface cleaned it up. Didn't remove much as you can see in the pic. Hit it again with Superstrip and turbo'd it. Then went for a final Superstrip and turbo for a final finish.