Re: [CAD_CAM_EDM_DRO] Re: Sherline Auto Tool Changer

Bernard and all,
I have added a self ejecting drawbar to my Sherline 5400 Mill.
After locking the spindle (another mod) a manual (or power) wrench
unscrews the drawbolt which immediately also pushes out the tooling.
Once the threads clear the collet, it drops into your hand.
The design is identical to that used on early Bridgeport mills
and some Clausing mills in the series 8520/30.
This device is locked to the top of the spindle by one dog pt setscrew.
RichD

"Bernard R " wrote:

>
> At one time I had an Emco FB2 which had a MT2 taper, the end of the
> taper was taped and it was tightened by a retained drawbolt, as you
> slackened the drawbolt it ejected the taper.
>
> Bernard
>
> --- In CAD_CAM_EDM_DRO@yahoogroups.com, "James Owens"
> <wotisname@l...> wrote:
> > Hi,
> >
> > I will have a think on this problem over the next week and come up
> with some
> > drawings. If a tool-holder is used, fitting into some sort of
> holder/adapter
> > which is fitted in the spindle, then there is no reason why the
> same idea
> > could not be used for Morse 1 - 3 and 30 int to 50 int and even R8.
> >
> > I don't like the idea of using parallel sides for the tool-holder
> but maybe
> > a self ejecting taper and an air chuck would do the job and still be
> > scaleable down to fit a Sherline.
> >
> > A small circuit board/stepper drive(s) using a cheap PIC would take
> care of
> > the CNC auto-tool change side of things from the lazy-susan, or
> even run the
> > whole thing on pneumatics under PIC control?
> >
> > Regards,
> >
> > Terry