RE: [CAD_CAM_EDM_DRO] Re: Feed hold with G-Codes

Hi Jerry,

We targeted the ELS at coming in under $150US for parts including the Z axis
Stepper driver for 3A and 50V. We've met that target easily. Cost of Power
supply, motor, belts, pulley's, couplings and spindle index sensor is the
same for a lathe regardless of CNC or ELS. Additional costs for the ELS
will be some sort of box to put it in and mount it.

OK. That's the money side.

Why the ELS? Because I didn't want to dedicate a PC (either on a cart or
permanently) to a Gingery 7x12 lathe. I didn't want to have to try and
remember G-Codes for setting up and simple turning. And I have run MACH2
LATHE on this lathe. There are a bunch more reasons.

My Gingery 7x12 doesn't have gears so it couldn't thread at all. My Unimat
DB200 can't thread. There are lots of older lathes out there missing a few
key gears. Many require all the messy removal and re-installation just to
change feed rate from 0.010" to a finishing pass of 0.003" so most people
don't bother.

My South Bend 10L can not only thread but has a taper attachment with the
telescoping leadscrew so I really don't need the ELS except for threads that
the SB, with the single lever gearbox, can't do. And there are some. Plus
Metric threads.

With the mass of that system, to keep the half nut engaged, then reverse the
spindle motor to go back to do another pass at some close approximation to
metric threads is another place for errors. Especially for threading up to a
shoulder. Like CNC, watch the carriage come flying up to the 3-jaw and stop
0.010" from the jaws is a sight to behold. Frightening really.

I've tried to make the operation of the ELS as intuitive as possible rather
than following a pure 'CNC World' approach. Only time will tell if I've
succeeded.

What I have succeeded at though, is that if I don't use the on board stepper
driver but connect the ELS one of the many breakout boards and external
stepper drivers, I just need to move the DB-25 cable from the ELS over to a
PC and I have a full CNC lathe... When I need it, if I need it. So I can
borrow the CNC pc from the mill for those infrequent times.

John Dammeyer

> Jerry Jankura
>
> Hi, John:
>
> I'm curious how the costs of the electronic leadscrew compare
> to simply
> using a standard CNC system. Other than costs, what
> advantages/disadvantages does the electronic leadscrew present?
>
> Thanks,
>
> -- Jerry Jankura
> Strongsville, Ohio
> Merry Christmas to all.... And to all a good night....
>
> > BTW, here's a couple of links to photos of the Electronic
> Leadscrew cut
> > tapers. MT1 and MT2.
> >
> > http://www.pacificsun.ca/~john/ELS/MT-1_taper.jpg
> >
> > http://www.pacificsun.ca/~john/ELS/T0.04988.jpg
> >
> > Roughness of Gingery Lathe not withstanding, they fit
> perfect the first
> > time. Granted this can be done with the MACH or TurboCNC
> etc. but this is
> > the stand-alone unit.
> >
> >
> > John Dammeyer
> >
>
>
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