Grit Media?

Jake; Even with a small pencil blaster you will remove the glaze very rapidly, use chemicals or just ignore it. I did the tile on my pool with acid and it came out nice. gary

I've read that baking soda is used for sensitive areas. Not sure how it'd work for your use. Otherwise, walnut or plastic beads might do the trick.

I want to be the first guy to tell you NOT to use sand because the silica particles can become lodged in your lungs and cause silicosis of the lungs... i'm always the reader of this warning, never the writer. I would also NOT use aluminum oxide, too aggressive. I do like the baking soda idea (people have used that on fiberglass corvette bodies with great success) and the crushed walnut shells seems to work well on softer metals. (somebody here said pet stores sell it as small critter bedding) Good luck, walt

I've used baking soda on a few bathrooms, with no visible damage to the tile glaze, but it makes a friggin mess, will peel latex paint off, takes a lot of baking soda and you need a very precise media valve on your blaster. I'm not sure why you say an acid wash is impractical. If at all possible, I would try a phosphoric acid based cleaner. This product has worked well on some nasty deposits:

Try some white vinegar first.

Any abrasive blasting will destroy the finish on the tiles. That leaves things like acid washes, CLR and it's competitors, Coke and vinegar (acid washes in other terms) for taking care of the problem. Yep, it is a mess but you ain't gonna do it any other way without risk of destroying the tiles.

-- Why isn't there an Ozone Hole at the NORTH Pole?

I have a similar problem with unglazed tile. Well, actually it is patterned and colored concrete that simulates unglazed tile. Acid washing doesn't differentiate between the unwanted minerals and the original surface, and neither would blasting.

What I've found that works is a light touch with the most aggressive nonwoven abrasive wheels from McMaster, and my 4.5" angle grinder. With the attack angle as low as possible, and the surface dry, it knocks the minerals loose and only slightly smooths the original surface - provided you move on once you see the original surface. If it is too aggressive for some areas, lowering the rotation speed works much better than moving to a finer grit. Wear dust protection!

Loren

Thanks All,

I guess that I will have to step back and punt. The tiles are on a spa that allows the water to cascade down into a pool. (Horrible idea) Every year I have to remove the residue. I have tried acids, paint scrapers and last year I broke out the big grinder with a heavy duty Scotch-Bright pad on it. It worked pretty well. This year the pool has water in it, so I don't want to use that electric grinder. A local pool guy told me that he blasts the tile. I was kind of concerned about removing the glazing, so that is why I asked.

I guess the next step is finding some sort of phosphoric acid gel like Naval Jelly. Damn, grit blasting sure sounded good. 8^(

Thanks again

Jake

ATP* wrote:

what about fastening your scotch-bright pad to an air tool (sander, etc)? you'd have to have a suitable compressor to run it, of course, but it would be safe. you could also use a buffing wheel on a flex shaft of some kind (large foredom, for example).

regards, charlie cave creek, az

Charlie, I don't think I could get enough torque out of an air grinder. The pad I used was 8" dia and was on 1+ hp grinder. I really had to lay on it to make it clean the scale and get into the grout creavases. Do you know of an inexpensive air angle grinder that might fit the bill?

Jake

Charles Spitzer wrote:

you might not need the torque. an air grinder will go so much faster and you can use a small pad rather than such a large pad.

you can also get a flexshaft that fits a normal .5 or .75 hp motor that you can mount a pad on. it's used, for instance, to polish car wheels in place, typically with cone type buffers. something like this:

You could blast it with baking soda, the soda getting into the water may not be a problem, it will just increase the pH. It does a number on grass, bushes, etc., so any aquatic vegetation may die. Is it outside or inside? Inside blasting with baking soda creates a major white shit storm. Outside with a dust suppression mist ring it's more tolerable. It will come clean fairly quickly. Wear a tyvek suit and use a decent mask.

Vim Bathroom Cleaner works well on those hard-water mineral deposits. You could spray it on, let it soak a few minutes, wipe it off. The stuff has a variety of acids in it.

Dan

Why not use the electric with an isolation transformer? That would be safe from the "electrocution" angle. ( being sure the xfmr is rated for the apropiate current )

...lew...

I don't know, standing up to my chest in water with an electric grinder in my hands while plugged into an isolation transformer doesn't give me warm fuzzys. I haven't got that much faith. 8^)

Jake

Lew Hartswick wrote:

Hey Charlie,

You win the prize. The acid was going nowhere and I was breathing too much of it. I headed over to Harbor Fright and picked up one of their angled pneumatic die grinders for 20 bucks (Not every job requires quality tools, especially when it stands a good chance of getting dropped in the water) I also got some 2" ScotchBrite disks. The set up worked great.

Thanks all for the suggestions

Jake > you might not need the torque. an air grinder will go so much faster and you