Industrial linings is my business so I have a degree of experience here. The brand of coating is not really all that important they will all adhere when proper prep is done. Selection of the coating is more a function of desired gloss, thickness of the system, and color. Fully cured 2 part epoxy is resistant to brake fluid if it is cleaned up promptly. I personally have the fleck in my work bench area, but did not carry it into the main floor - it is not easy to get the fleck uniform - results will vary, and a nice fresh neat epoxy floor will look blotchy after the fleck is installed if you are not used to doing this all the time...
Terry - you are correct it is
all in the prep, but for purposes of clarification, "Acid washing" will not help if you are going over an existing coating.
Acid washing is used to etch the bare concrete by attacking the cement matrix at the surface. Remember, these coatings are "acid resistant". Acid washing, properly done, and thoroughly rinsed, is an acceptable method for existing concrete.
Sand blasting, while technically will work, is not practical, nor is the previously mentionned shotblasting, unless you know someone in the business with this equipment.
Assuming the existing coating is well bonded, rent an industrial floor sander like used for hardwood floors. Use a coarse pad, and knock the glaze off. Clean thoroughly removing all dust - wash it, and dry well. Corners and edges by hand.
For exisitng concrete, the do-it-yourselfer is best to rent a high pressure water blaster, and go the acid etch route - lots of water, use a squeegee, rinse well, repeat until you think you have it well done, and then do it again. Rinse with TSP, then flush with lots of water - this of course is really only practical if you can flush to a drain .
This is an ok job for the do-it-yourselfer, but a 20x20 garage will eat up the most part of your weekend.
Good luck,
