Re: [CAD_CAM_EDM_DRO] Small Problem

Hey Jerry~!

From: "Carol & Jerry Jankura" <jerry.jankura@...>

> I'd strongly suggest that you dig into your pockets a little deeper and go
> with the bipolar drivers. Years back, I used some of the unipolar drives

in

> an industrial application. In order to get any performance from the

motors,

> we needed a relatively high voltage power supply and some really large

power

> dissipation resistors which were put in series with each of the motor
> windings. The resistors ran really hot.
> Contrast that with some projects I've worked on more recently that were
> implemented with bipolar drivers. First, no series resistors were required
> so the entire system ran cooler. And, the motors were really "stiff." That
> is, they really ran well and did not want to stall or drop steps

(important

> in CNC where you are essentially "counting steps" to know where you are).

Okay, understood, but I have to ask - (no, I'm not trying to squirm outta
the money)
For a home/hobby type CNC mill or plasma cutter,
is the difference *that* great?
Obviously, we know it *can* be done by uni's for
the type of stuff I want to do, but I'm not talking about
running them in 8 hour shifts, 5 days a week.
(Remember, I work as a Tool & Die maker all week)
These are mainly for me to play with and knock out ideas
and prototypes, or otherwise complicated parts.

> I just went through the same exercise that you are going through and

decided

> on the Camtronics 2 amp board. My decision was made based on a couple of
> things: First, the motor current requirements matched the driver's
> capabilities.

Okay, this got my attention.
Am I supposed to make the motor decision first, and then find a suitable
driver?
That *does* throw a twist in the works.

>Second, I don't mind building a kit and adding the "extras"
> required to make a "stand alone" controller.

Absolutely agreed.
Besides having more time than money,
I like putting things together.

> Third, both Gecko and
> Camtronics have received several favorable comments on this list and no
> negatives. I have already received the Camtronics toys and assembled them,
> but have not tested them because I'm still waiting on delivery of the

motors

> and mechanical coupling to the Sherline mill.

Hmmm, okay...
*Which* Camtronics didja get?
And will a bipolar "chopper" driver run a unipolar motor?

> Hope this clears a little mud from the waters.

It's helping.
Thank you for taking the time.

Weyland