Dating quartz grains
Note that the specified pressure for initial set would permit an 250 lb worker to walk on new plaster with only 4 or 5 square inches of footprint.When working plaster, do not be confused with "false set" or "flash set".Despite what the contractor's salesmen want you to believe, it is not a mysterious material containing diamonds or secret ingredients.While the aggregate in common concrete (such as is used to pour slabs and sidewalks) is stone gravel in a blend of sizes, in pool plaster the aggregate is fine quartz sand (also called silica sand, quartz being also called silica) or very fine marble dust.Refinishing was badly needed by the time we owned this house and summoned the will to attack the refinishing project. I am not such an expert, having done all of one job in degrees from tear-out-and-do-over bad to will-be-fine-after-it-sets-and-we-polish-out-some-problems.The entire project eventually encompassed far more than replastering. No, that's not Mountain Dew, it's EPA-approved chloraminated tap water! I had nothing but manufacturer's instructions and Web research to learn from, but I know a few things about physics, chemistry, and materials that helped me discover enough to do a passable job on the first try.
For a red-blooded guy who does his own oil changes, what else could I do? That's as much due to the diligence of the homeowner's self-motivation, which is his unique advantage over the tedium of labor, as it is to newly acquired skill.
This is a stiffening that happens soon after mixing or placement.