We are getting there. First bit. Yes the screwcutting will have to be set to the same pitch as the tap. Because the TAP is tapered the lead or start part, ie. the thinnest part, will finish up at the thick end of your male thread.The tail end or thick part of the tap will produce the thin end of your male part.
Imagine a chamfering tool ground to 45 degrees and traversed along the bed. It will produce a chamfer on the work at 45 degrees. Now tilt this tool so it is at an angle of 5 degrees and traverse that across and all the while it's on the face of the tool it will produce a male spigot with a 10 degrees included angle. That's the part you are trying to duplicate with your tap but not at
10 degrees, that's just an example.-- Regards,
John Stevenson Nottingham, England.
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