Re: [CAD_CAM_EDM_DRO] Re: Sherline Spindle Pulse disk for threading

On Sat, 10 Nov 2007 15:59:37 -0800, you wrote:

>You don't want it adjusting over the threading pass or even a different
>speed per pass. You want a stable spindle speed in the first place.

Agreed, the latter is the less of two evils.

>I do have a question for you Steve. If you are using the G76 to cut the
>threads, one of the parameters is thread depth. If, after the G76 is
>done, the nut doesn't fit because the lathe and work flexed such that
>the depth wasn't cut, how do you fix this? Set a deeper depth and run
>the G76 again? Do some sort of special G76 as a single spring pass?

Not here - I'd scrap that part and re-do it with more passes.

I always run one or two spring passes anyway.

You need to set the parameters so that doesn't happen in the first
place. If that means doing test pieces on the same material, so be it.

BUT - If the lathe flexes that badly, get a new lathe ;)

For fine work that's likely to deflect I always use a die and holder or
box tool. Support with centre & tailstock on long threads.

Steve Blackmore
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