Reply To: lathe projects.

[AjohnwParticipant @ajohnw51620]

If you have the right sort of screw cutting indicator many metric threads can be cut using the it directly in much the same way as imperial threads. I assumed that your Vicroy would have one and that it's likely to be similar to a Boxford one. That works this way

Lathe parts can make this type of indicator or people could have a go at making one themselves. An M3 acme tap could be used to finish of the gears providing they aren't too thick for the size of tap used. It's best to cut slots at more or less the correct pitch first by hand. If the equipment is available it's simpler to just cut a gashed gear – straight teeth at an angle to suit the angle of the thread.

Must admit I have stuck to imperial because of the pain metric threads cause in this respect. The catch with indicators like this is the time it can take for the correct index marks to come round on some pitches.

The screw cutting nut can always be disengaged if the method I outlined is used. It helps when working up to a shoulder.

John

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