Re: [CAD_CAM_EDM_DRO] Tapping success!

figNoggle wrote:

>hi vince-
>
>great to see a manual tapping head work under cnc. did this with a
>tapmatic 30x using #6 taps and broke more a handful within minutes on the
>cnc'd minimill. but then again, the holes were more more than 1/2" deep :)
>
>haven't yet tried the 50x on a full sized mill (it's too big for
>mini-mills) but glad to see that'll work.
>
>

I've done hundreds of 4-40, 6-32 and 10-32 holes with a Procunier
15000 series "CNC" tapping head. This has no overload clutch, and
reverses when the spindle pulls on the tap, same as Vince's.

I only broke taps when I did something wrong, like forgot to set the
Z axis before starting. I did break some 4-40 drill-taps because I
had the drilling plunge too fast. I had to drill at (ver roughly)
1/4 the tap feedrate and then speed up to the threading feed after
the drill point broke through. I did a plate with 144 10-32 holes
(drilled first, then tapped with tap-only tooling) with no breakage
at all. I use only spiral FLUTE taps with the tapping head, even
when doing through holes. I don't know if this is necessary, but
these taps just seem to work better when just blasting the tap all
the way through without backing up.

I did use the Procunier on blind 6-32 holes drilled 3/4" deep, then
tapped to 1/2" depth. I think I did break one tap somewhere in the
~600 holes in that job.

Jon