Re: Servo as a Sherline spindle motor ?

----- Original Message -----
From: Andy Wander <awander@...>
To: <CAD_CAM_EDM_DRO@yahoogroups.com>
Sent: Thursday, December 18, 2008 8:36 PM
Subject: RE: [CAD_CAM_EDM_DRO] Re: Servo as a Sherline spindle motor ?


> Phil:
>
> It's in-lb or in*lb, NOT in/lb.
>
> ______________________________________
> Andy Wander
>
> -----Original Message-----
> From: CAD_CAM_EDM_DRO@yahoogroups.com
[mailto:CAD_CAM_EDM_DRO@yahoogroups.com] On Behalf Of Yahoo
> Sent: Thursday, December 18, 2008 7:01 PM
> To: CAD_CAM_EDM_DRO@yahoogroups.com
> Subject: [CAD_CAM_EDM_DRO] Re: Servo as a Sherline spindle motor ?
>
> Right. I meant to type in/lb. Stupid fingers! In any case it shouldn't be
> too hard to stall.
> --
> Phil Mattison
>
>
> ----- Original Message -----
> From: Dave Sage <davesage12@...>
> To: <CAD_CAM_EDM_DRO@yahoogroups.com>
> Sent: Thursday, December 18, 2008 12:09 PM
> Subject: [CAD_CAM_EDM_DRO] Re: Servo as a Sherline spindle motor ?
>
>
> > Correct me if I'm wrong but:
> > 16 oz in a pound, 12 inches in a foot
> >
> > 150 oz/inches equals:
> > 150/16/12 = approx 0.8 ft/lbs.
> >
> > Sage
> >
> > --- In CAD_CAM_EDM_DRO@yahoogroups.com, "Yahoo" <yahoo@...> wrote:
> > >
> > > 150 OzIn peak is about 9 ft/lb so you probably could stall it if
> > you had a
> > > better grip. Lacking a dyno (doesn't everyone have one?) maybe a
> > reasonable
> > > comparison would be to wear leather gloves and stall both motors
> > with your
> > > hand to see how they compare. You probably want the servo to be
> > stronger
> > > than the stock Sherline motor anyway to get the low-end torque for
> > > threading. Quite a bit stronger I should think.
> > > --
> > > Phil Mattison
> > >
> > >
> > > ----- Original Message -----
> > > From: Alan Rothenbush <alan@...>
> > > To: CAD CAM EDM DRO <CAD_CAM_EDM_DRO@yahoogroups.com>
> > > Sent: Wednesday, December 17, 2008 9:06 PM
> > > Subject: [CAD_CAM_EDM_DRO] Servo as a Sherline spindle motor ?
> > >
> > >
> > > > Thanks to all who responded to my question about my 5mm pulley
> > bore. I
> > > have some coming and I'll try to bore them out and cross my fingers.
> > > >
> > > > That pulley is destined for the end of a double-stack NEMA17
> > stepper that
> > > will be used to drive the cross slide of a Sherline lathe that I'm
> > FINALLY
> > > getting around to CNCing properly.
> > > >
> > > > One thing I'd like to try on the Sherline is CNC threading.
> > > >
> > > > I see two ways to do this.
> > > >
> > > > 1. Put a servo on the spindle and write a bit of custom code; no
> > real
> > > problem, or
> > > >
> > > > 2. Put a nice fat motor on the spindle (so there's no worries
> > about it
> > > slowing down) and use one of the "spindle sensor" options.
> > > >
> > > >
> > > > Option 1 is certain to work AND I have all the bits at hand;
> > spare gecko
> > > G320, a choice of servo motors, and some L series pulleys.
> > > >
> > > > The one little fly in the ointment is that the choices for servo
> > motors
> > > are
> > > >
> > > > . one that's SEEMS a wee bit small or
> > > > . one that's WAY WAY WAY TOO BIG and would be wasted in this
> > application.
> > > >
> > > >
> > > > The smaller motor is an older EG&G Torque systems ME2610. It is
> > > physically pretty close to the same size as the stock Sherline _AC_
> > sewing
> > > machine motor, if that means anything. (It's an old lathe).
> > > >
> > > > I can find no specs on the PRECISE motor, but I did find some
> > specs on a
> > > similar motor from the same manufacturer (same dimensions, similar
> > part
> > > number). That motor is rated at 29 OzIn continuous, 150 OzIn
> > peak. This
> > > does not seem like a whole lot of torque to me.
> > > >
> > > > On the other hand, I can't stall it with 36 volts driving it by
> > grabbing
> > > the 1" pulley, so maybe 150 OzIn is more torque than it seems.
> > > >
> > > >
> > > > Anyway, I'm looking for thoughts, opinions and experiences; all
> > comments
> > > gratefully accepted.
> > > >
> > > >
> > > >
> > > > Alan
> > >