1 00:00:09,250 --> 00:00:11,583 Hello, and welcome back to Heart of Worcestershire College. 2 00:00:12,083 --> 00:00:14,666 This is the next in the series of toolbox talks. 3 00:00:15,625 --> 00:00:19,208 Last week I introduced you to the Zeus Book. 4 00:00:19,500 --> 00:00:21,041 I'm just going to show you an example 5 00:00:21,041 --> 00:00:23,541 now of how we can look for some information in here. 6 00:00:24,041 --> 00:00:27,375 So today I've decided that we're going to look for information 7 00:00:27,375 --> 00:00:31,666 surrounding tapping drill size for a twelve mil thread. 8 00:00:32,958 --> 00:00:35,958 So this is a twelve mil 9 00:00:35,958 --> 00:00:38,500 tap, a taper tap, the first one that we use 10 00:00:39,000 --> 00:00:42,458 and we need to work out how much we've got to drill a hole. 11 00:00:43,125 --> 00:00:47,583 Now in here I can see if I look down twelve mil. 12 00:00:47,583 --> 00:00:52,333 The tapping drill says 10.2 So 10.2 13 00:00:53,750 --> 00:00:55,791 is the drill size that we need to use. 14 00:00:56,125 --> 00:00:59,083 The reason being for that is that pretty much 15 00:01:00,416 --> 00:01:02,250 if you were to strip 16 00:01:02,250 --> 00:01:04,291 all of the threads off that 17 00:01:04,875 --> 00:01:08,166 the core of this tap would be 10.2. 18 00:01:09,500 --> 00:01:13,125 So we drill at 10.2 in order to leave enough metal in there 19 00:01:13,416 --> 00:01:16,166 so that we can put that thread in there 20 00:01:16,750 --> 00:01:19,000 because here is a twelve mil drill. 21 00:01:19,916 --> 00:01:21,625 Twelve mil tap / twelve mil drill. 22 00:01:21,625 --> 00:01:24,208 That would fall straight through if we use that. 23 00:01:24,708 --> 00:01:27,208 So by the use of this book, 24 00:01:27,208 --> 00:01:29,541 we know what size we need to be drilling it. 25 00:01:29,875 --> 00:01:32,166 Now this is true of any thread pattern. 26 00:01:32,541 --> 00:01:37,208 I chose twelve mil but we could have some of the metric ones. 27 00:01:37,208 --> 00:01:41,000 We could have BSF, DSW, 28 00:01:41,541 --> 00:01:44,083 British Standard Pipe, BA. 29 00:01:44,541 --> 00:01:47,833 The list is endless, so I hope that's been some help for you today. 30 00:01:48,708 --> 00:01:49,083 Thank you.