Re: Help with Bridgeport retrofit parts and plans

>
> There are many new series type 34 motors that are more powerfull

than the original Bridgport ones with less inertia to boot.

> Bridgeport originally fitted anything from 950 ozin up to 1100

oz/in in the 42 frame.

> I have seen some triple stack 1700 oz/in motors in a 34 frame

advertised.

>
> What makes you think that one of these will not work ?
>
> My Beaver mill which is bigger than a Bridgeport runs 950 oz/in

motors direct onto a 5tpi ballscrew with no problem.

>
> John S.
>

For my reasoning on steppers and Bridgeport's read my post #80854.

I can understand why your Beaver is direct drive. With all the
torque on a stepper in the 300 rpm and lower range it would have no
speed with a belt reduction.

I also think many people would consider the step of a direct drive
motor to coarse.
Assuming .2" lead screw each full step would be .001". Even half
step is a little rough.

I would like to hear some real world specs on the beaver.

1 What are the rapids.
2 What is maximum IPM you can take a good cut with.
3 If you cut a circle, what does the finish look like.
4 What is the lead on the ballscrew.


Wally




--- In CAD_CAM_EDM_DRO@yahoogroups.com, "John Stevenson" <john@s...>
wrote:

>
> > --- In CAD_CAM_EDM_DRO@yahoogroups.com, "CalBoy101" <pt@f...>

wrote:

> > > Hello-
> > >
> > > I'm planning to do a stepper motor CNC retrofit on a Bridgeport
> > > clone mill. I'm starting to figure out what I'll need, and any

help

> > > with or comments on the following would be great. Money is

tight so

> > > I'm trying to go with suppliers where I'll get both acceptable
> > > quality and good pricing.
> > >
> > > Stepper motors-
> > >
> > > From what I can tell, for a Bridgeport size mills, 1200 to 1300

oz-

> > > in. motors seemed to be commonly used. I'm considering the ones

from

> > > http://www.camtronics-cnc.com/ I'm looking at their models:
> > >
> > > 1H34-113 1303 OZ IN 2.5A $195
> > > 1H34-114 1303 OZ IN 4.5A $195
> > >
> > > Does anybody have any comments on these motors for this

application

> > > or a suggestion of better motors?
> > >
> >
> >
> > I have never seen a nema 34 stepper that could drive a Bridgeport.
> >
>
> There are many new series type 34 motors that are more powerfull

than the original Bridgport ones with less inertia to boot.

> Bridgeport originally fitted anything from 950 ozin up to 1100

oz/in in the 42 frame.

> I have seen some triple stack 1700 oz/in motors in a 34 frame

advertised.

>
> What makes you think that one of these will not work ?
>
> My Beaver mill which is bigger than a Bridgeport runs 950 oz/in

motors direct onto a 5tpi ballscrew with no problem.

>
> John S.
>