Is the only way to drill holes in 3/4" granite slab say a 3/16 hole, is with a hammer drill?? I tried the Bosch Blue Granite to install some grab bars in a shower w/granite walls and it went pretty easy on one install I did awhile back, no hammer action. Then today, again grab bars in granite shower(black granite), the first hole was no prob, 10 min., the other 5 holes took about a half hour each.???