Bricks, Masonry, Asphalt and Concrete - Cleaning concrete floor for tile

HELP
I have a house with a slab floor built in 1950's. Original floor covering was 9" black tile (probably asbestos) glued with a black tarry type of adhesive. Tile are all gone now, but the adhesive remains. I can clean it up with kerosene real easy, but then the concrete doesn't absorb water, so thinset doesn't stick very well. Does anybody have any experience with this sort of thing and what would be recomended to get the stuff off the floor so I can tile it................................................:confused:

I have the same problem, I am using paint thinner to break up the glue, it works well but I am going through a lot of rags to soak up the glue but it cleans the floor very well. I can see the sealer on the concrete now. I posted the same question a few weeks ago and the only response was to use a 4" scraper, it just slid across the glue, I tried a razor blade that wasn't any good either. I tried "Adeasive Remover" from HD it was 6X the cost of the paint thinner and wasn't that imppressed with it.

Ya, any hydrocarbon based solvent will take the stuff off, but it also seals the concrete pores with the created goo then the thinset doesn't stick very well. I have had some success with a cheap sandblaster from Harbor Freight but it is slow and makes a terrible mess. BUT the concrete is nice and clean and water wets it. Also had some success with just a plain scraper when the stuff is cold (40-50 degrees) but it is way too slow. I've got about 800 square feet of the stuff and I need something faster and easier.
Somebody out there must have solved this problem...................

You can go to any equipment rental store and get their tile adhesive remover. Once you apply and remove that, acid etch the floor, which will get rid of the leftover goo and neutralize with baking soda and water.

Is that a chemical remover or something mechanical? Any brand name? I'll try anything at this stage

Thanks

I have always used a hammer drill (hammer only tool) and what was called a flexible chisel - I rented one at Home Depot. By going the mechanical route, you will not have the problem of the thin set not sticking as any chemical product will soak into the pores of the concrete and prevent a good bond. I also used a 7" grinder with a vacuum attachment and a diamond cup wheel that also worked great. A little more costly though.

What exactly is a flexible chisel for a hammer drill? Any brands or where it's available? I have an SDS hammer drill but I've never seen a flexible chisel for it. Home Depot has the small SDS Bosch chisel, but it's rigid and for breaking concrete.

A flexible chisel is a wide flat chisel about 4 1/2" wide and the face of the chisel is about a 12 gauge thick sheet metal. This type does not break up concrete. Comes in SDS, SDS MAX and a couple other larger connection ends. I have seen this style made by HILTI and Bosch. Should be available from most rental yards or direct from Hilti or Bosch.

Thnx for the info. I'll check out the Hilti display at HD. Also will check out the builders supply place. They seem to have most every bit for drills in every conceivable size and config. The best thing they had were these big (like 3/8" to 3/4") concrete screws that are great for putting down plates. Ya just drill a hole and turn em in. The SDS hammer drill made the holes in seconds. Sure beats the little tapcon screws and a regular masonry bit in a cheap hammer drill.:cool:

Think I finally found something to do the job. It's a needle scaler from good ole' Harbor Freight, $50 on sale. The also had a gasket scraper for $20, both air driven. Between the two, I can get the goo off the floor, the colder the better. It's slow, but the tool does the work and leaves a nice clean surface almost as good as the sand blaster did but without the mess. :)