Re: Home made CNC rotary table??

Jeff -

By the sound of it, you may well never need one.

However, as an alternative to using a manual indexing device, it is a
lot cheaper to use a dedicated controller like DivisionMaster than
going for a full-blown CNC setup. For example, I sold one yesterday
to a guy who makes clocks & is fed up with the problems associated
with manual divisions...you know how it goes...you've just wound the
indexing arm by two full turns & 5 extra holes in the division plate
(or whatever) & the phone rings. 5 minutes later, you have no idea
where you left the job, & the part is now scrap because you end up
making a thick or thin tooth. This guy will probably never buy a full
CNC rig, but will gain a considerable advantage in time & effort by
using an automtic indexer.

Also, as the controller is a lot more portable than the average CNC
control & associated power supplies etc., it can be really convenient
if you plan to use your rotary table etc. with other, manual
machines. See John Stevenson's earlier posts for examples.

Regards,
Tony

--- In CAD_CAM_EDM_DRO@y..., "jeffdavis516" <cadman@p...> wrote:
> Thanks for the links. Why would I need a separate controller to
> control the rotary table? I would just power it with a 4th gecko
and
> use my CAM software to create the gcode. Is there any other reason
> to have a separate hand held controller for a rotary table?
>
> Jeff
>
>
>
> --- In CAD_CAM_EDM_DRO@y..., "stevenson_engineers" <machines@n...>
> wrote:
> > --- In CAD_CAM_EDM_DRO@y..., "jeffdavis516" <cadman@p...> wrote:
> > > I'm wondering if anyone here has any experience with making
your
> > >own
> > > CNC rotary table. I'm not interested in the small one from
> > >sherline
> > > but maybe a 6" or 8" size. Has anyone taken a standard one and
> > > somehow removed the backlash and added a stepper or servo motor
> to
> > >it?
> > >
> > > Maybe there are places that sell ones ready that are not too
> > > expensive :)
> > >
> > > Thanks
> > > Jeff Davis
> >
> > Jeff,
> > Take a look at http://www.divisionmaster.com
> > Have a look at the examples page and also have a look at the
> > following three files.
> > http://homepage.ntlworld.com/machines/5cga.jpg
> > http://homepage.ntlworld.com/machines/5ccomplete.jpg
> > http://homepage.ntlworld.com/machines/vertex_GA.jpg
> >
> > The first file is a general arangement shot of a standard el
cheapo
> > J&L 5C spin indexer being converted. The worm gearbox is a
standard
> > popular Italian reduction gearbox that is very common in the UK
and
> > also cheap.
> > Second shot is the finished indexer with a samll 3" 5C chuck
fitted.
> >
> > Last shot is an 8" vertex table converted to stepper drive and
> being
> > driven by the Division master unit on a manual Bridgeport.
> > This is a shot of cutting some pneumatic face seal valves.
> >
> > The Divisionmaster is similar to the Sherline unit but because
> it's
> > more versatile it's only just reached the market.
> > You can program this for jog speed, cutting speed, number of
> > divisions of the reduction, backlash and motor amps to name a
few
> > points that differ from the sherline unit.
> > It also puts out step and direction so you can drive bigger units
> > with it. I have mine running a Gecko 210 on 74 volt 7 amp to run
a
> > big Hoffman dividing head powered by 1,100 ox in type 42 stepper.
> >
> > John S.