Re: [CAD_CAM_EDM_DRO] Re: General Tool Life Question

Hi Hugh:
Spiral flute taps will pull the chips out of the hole as they cut.
They are used for power tapping blind holes because of this feature.
They're no better than spiral point taps for hand tapping, though
They do have one significant shortcoming.
Since they are spiral fluted, they can, on occasion, untwist in "grabby"
materials at the point at which the spindle is reversed.
Untwisting them makes them jam in the hole, and break.
They are the devil's very own to get back out.
Even EDM can be problematic, because you're left with 3 spiral strings when
you burn out the core.
These will sometimes flop around in the hole and short the electrode.
Cheers

Marcus

----- Original Message -----
From: Hugh Currin <currinh@...>
To: <CAD_CAM_EDM_DRO@yahoogroups.com>
Sent: Wednesday, January 16, 2002 3:05 PM
Subject: [CAD_CAM_EDM_DRO] Re: General Tool Life Question


> Jon & all:
>
> I was told recently that these spiral flute taps work better than straight
> taps for both hand and machine tapping. Does your, or anyone's, experience
> back this up? What are the advantages of these sprial flute taps?
>
> Thanks.