Re: [CAD_CAM_EDM_DRO] Using a tapping attachment with a CNC bore cycle

"Fitch R. Williams" wrote:

> I picked up a Procunier 1500 series tapping attachment on Ebay. It got
> here today so I spent some time looking at it, making friends with it,
> sort of. It has what I think is a setup for a tool changer - it locks
> the spindle when it comes full up, so I took that off since I don't have
> a tool changer.
>
> I put it in the manual mill, it will unscrew its collet chuck if I pull
> on it while the mill is going around. Hold it, it screws on. pull
> lightly and it unscrews at 2X speed.

This sounds like a 15000 CNC tapping head. I have one, too.

>
> I think it will work with a standard bore cycle. If the 2X speed has it
> trying to get ahead of the retracting quill, my thinking is it should
> just disengage and stop till the quill gets ahead again.

But, it is just as easy to make the retract at twice the speed as the
plunge. I have a program that writes a tapping cycle in G-code to
do it without requiring any canned cycles or special G-codes. It
is all done with G01. See http://pico-systems.com/recttap.c for
the C source to tap a rectangular grid of holes. I thought I had
DOS executables of the one-hole program and this one handy,
but they aren't. I will add them to my web page for G-code programs.

> I'm planning on adding a handle that sticks out to the side like I see
> in the catalog pictures. At that point I run out of notions on how to
> use it. Do I add something that sticks down to keep the handle from
> rotating? How is this done - are two things put there so the handle is
> captive? Or is it allowed to rotate a full turn?

Bridgeports have a 1/4" (I think) vertical hole to the right of the spindle.

People hook lights, coolant systems, shields, etc. to this. I usually have
my coolant nozzle attached there. But, I can put a rod there when using the

tapping head.

I just set it so that the reaction torque holds it against the rod, so it is
not
constrained. If I do it wrong, it spins around once, which usually makes
me jump a little.

Jon