Although not an absolute, this is typically not a problem with your locks. A “new” one is often not a “new” one at all. Taking a worn out blank and duplicating it, means you are simply copying all the wear right back onto a brand new duplicate. Although your new copy will be considerably stronger than your old one because the new blade doesn’t have all the wear down the sides, the actual cuts on the duplicate are usually worse than the original. This is because no duplicating machine cuts an exact copy. The 2nd generation copy has all the wear plus any slop from the duplicating machine added in! Even as little as 2 or 3 thousandths of an inch is enough to make a big difference on duplicates and it becomes even worse if the blank being duplicated also started life as a copy. Our machines are kept closely calibrated to help avoid this, but the true cure is to “originate” a brand new blank. Quite simply this means to cut a key that corresponds to the factory code. There is a small fee to do this, but 99 percent of the time this is the best solution to the problem.