- Joined
- Feb 17, 2021
- Messages
- 496
just read a drill/tap chart that sez a 7/32 drill would work for the 6.0x1m tap....thats a hair under a 1/4 ..sound right??An M6 x 1 Translated: M for metric, 6 for the nominal diameter in mm, 1 for the thread pitch (1mm crest to crest) Tap drill size is = to the nominal diameter minus the thread pitch (6-1=5mm, find the drill closest if you don't have metric drills. That is a very common size, similar to 1/4" Imperial but won't interchange. Many configurations of taps are available. Easiest to use by hand is a taper tap, next is a plug tap. A bottoming tap should only be used after one of the others as it is almost impossible to start straight by hand in a drilled hole.
It sounds like you have little experience with tap & die use. Watch some videos before you try it. Tapping fluid helps but even almost any oil will work better than nothing. No fluids are used on cast iron. Go easy and back the tap out often to clear the chips and keep it from breaking. It is all too easy to break small taps. Probably worth practicing on some similar metal before the good part. Be very careful to start straight. Taps are hard and brittle!
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