Anyone know how to check an external (due to old rule number 3) thread for pitch also so i can use it as a Datum ? Any simple step-by step direction would be awesome!!!
What we use is a center scan. We're finding the pitch diamter of a sprocket using a stylus with the same diameter as the pin called out on the drawing. The center scan probes down one side of the tooth until it touches the adjacent tooth flank. Then it pauses for a second to equalize the pressure in the probing system to register a point. But you MUST have a scanning system for this to work with.
Thanks! I found it. It is a "basic scan".
So for the OP, you would need a scanning system, a probe that is the wire size, then you would have to decide a way to "clock" the thread and calculate the location of 4 points on the pitch diameter, at least two levels, then center scan each point, from those scans you should be able to construct the pitch diameter cylinder.
What we use is a center scan. We're finding the pitch diamter of a sprocket using a stylus with the same diameter as the pin called out on the drawing. The center scan probes down one side of the tooth until it touches the adjacent tooth flank. Then it pauses for a second to equalize the pressure in the probing system to register a point. But you MUST have a scanning system for this to work with.
Thanks! I found it. It is a "basic scan".
So for the OP, you would need a scanning system, a probe that is the wire size, then you would have to decide a way to "clock" the thread and calculate the location of 4 points on the pitch diameter, at least two levels, then center scan each point, from those scans you should be able to construct the pitch diameter cylinder.
