Peefor
Veteran
Location: St Albans UK
My Posts This: Topic Forum | The metric threads generally used on helis are from the Coarse range. So an M3 'normal' would be 0.50 pitch which equates to about 51 TPI.
The other Metric range is Fine. There can be a couple of choices of pitch in the Fine range though.The corresponding M3 Fine is 0.35 pitch.
In M8, the standard coarse is 1.25 pitch, but the Fine range can be 0.75 or 1.0 pitch. The clutch bell on the raptor is a case where the Fine pitch is used.
The ISO standards can be found here..http://www.engineeringtoolbox.com/m...eads-d_777.html
Of course there is nothing to stop anyone with a machine making any diameter with any pitch, but nobody else's nuts will fit. :-)
Pete |
For awhile their I thought I had a British National Standard Pipe tap or something.
