A.Mark Brooks, technical services manager with Laticrete International, responds: For spot removal of excess epoxy grout, your best option is to use a heat gun capable of reaching 500°F. (Don't use a torch, which is too hot and may scorch or crack the adjacent surfaces.) The heat gun will soften the cured grout so that you can scrape it off the fixtures and out of the screw slots. After you've removed the grate, you should be able to clean the softened grout from it too.
You can also use this approach to remove individual tiles, though mechanical or chemical methods are suggested for large-scale grout removal. (For more information, see Laticrete's technical data sheet TDS-400 at www.laticrete.com.)
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