Re: [CAD_CAM_EDM_DRO] Re: Resetting the head on a Mill Drill

>
>
> cadman@... wrote:
>
> > Now I understand what this thread is all about. One of the
> > requirements of the drill/mill was a large quill travel. The ENCO I
> > purchased has 5" of travel. I don't plan to move the head in the
> > middle of a job. For my use, 5" of Z travel is fine.
>
> Well, I have 5" of quill travel on my Bridgeport, and that still isn't
> enough, once in a while. Of course, I also have the knee to move, so
> it isn't a big problem. But, when a part comes along that needs a
> 1/8" end mill for part of the work, and a 1/2" drill bit for another part,
> it becomes a problem. You either need an extended holder for the
> 1/8" mill, or a cut-down 1/2" drill. A 1/2" jobber's length drill is
> pretty long, and when you add the Jacob's chuck, it is more than
> 5" longer than the small end mill.
>

They do make shorter length drills, which have the added advantage of
not needing to be spotted with a center drill first.

And for a size like 1/2" you can hold the drill in a collet
and skip the space needed and inaccuracy added by a drill chuck.

But if one needs to use say the 31/64" drill out of the jobber-length
set on hand, and doesn't have R8 collets by 64ths (who does?) then
the problem you state is very real!

Chris
(whose mill has scarcely more than 2" of quill travel,
but a knee to partially compensate)

--
Christopher C. Stratton, stratton@...
Instrument Maker, Horn Player & Engineer
22 Adrian Street, Somerville, MA 02143
http://www.mdc.net/~stratton
NEW PHONE NUMBER: (617) 628-1062 home, 253-2606 MIT