Re: Stepper Size Selection

--- In CAD_CAM_EDM_DRO@yahoogroups.com, "dnaman43" <mevagissy@...>
wrote:

>
>
>
> --- In CAD_CAM_EDM_DRO@yahoogroups.com, Steve Blackmore <steve@>
> wrote:
> >
> > On Sat, 14 Jun 2008 21:13:13 -0700, you wrote:
>
>
> > SX3 conversion here with 340 oz/in motors direct coupled to 4mm

pitch

> > ballscrews is capable of 5m/min without loosing steps or

stalling, but

> > it's tuned down to 3m/min (120 ipm) which seems a more sensible

speed

> > for a small machine. Chinese Leadshine drives at 50VDC @ 4A
>
> That ties in well with Michael's comment which is encouraging.
> >
> > Spindle motor's been replaced with a 180V DC 2Kw motor, 0-3200

rpm.

> >
> > It's reliably taking .2" deep cuts with a 1/2 inch two flute slot
> drill
> > at 20 ipm and 3000 rpm in 2017 Aluminium.
>
>
> That would way exceed my expectations or needs. Then again I only

have a

> 600W spindle motor.
>
> Thanks for the response, Steve. Things are getting a lot clearer.
>

It seems your machine is a re-labled or clone of an Opti BF20 Vario
mill.

There are several kits for this in Europe and the UK.

Take a look at
"http://www.optimum-
machines.com/fileadmin/Produkte/Optimum/Erlaeuterungen/GB/bf20cnc.pdf
"

They use 3A 2.2Nm steppers with a belt reduction.

The pics in the PDF should give you some ideas.

Often using the belt reduction will give faster rapids without lost
steps - Torque drops off fast with steppers so the leverage of the
reduction often has more torque than what the motor running 1:1
would have at a slower speed.