Re: Servo hardware

--- In CAD_CAM_EDM_DRO@yahoogroups.com, Jon Elson <elson@...> wrote:

> Oh, HELL! I skipped right over the part about true closed loop! I just
> saw "small mill and steppers".
>
> OK, the problem here is that there really is no such thing as "true
> closed loop" with stepper motors. You can get error detection, but you
> can't do anything about it except declare a following error and halt.
> That's better than blindly going on after steps have been lost, but a
> stepper drive cannot recover from a stall until you come to a complete stop.
>
> But, if you are willing to replace the motors, too, then there are options.
> I have a universal PWM controller that closes the loop through the PC.
> I have brushless servo amps, and am now carrying some brushless motors
> from Keling. These are size 23, but are so insanely powerful you won't
> believe it. I don't sell power supply components, but can recommend
> where to get the parts. The power supply is simple.
>
>
> So, the kit for 3 axis is :
> 1 Universal PWM Controller $250
> 3 brushless servo amps 450
> 3 brushless motors with encoders 360
> total $1060
>
>
> You can see these products at
> http://pico-systems.com/oscrc4/catalog/index.php?cPath=3
>
> There are various other options, such as to add a jog pendant, spindle
> encoder for rigid tapping, spindle speed control, etc.
>
> Thanks for the heads up that I answered the wrong question!
>
> Jon

Jon or anyone,

Seems like a super solution, but over kill for a Sherline, Taig, A2Z Monster Mill sized machine. I would almost be afraid that a learning crash could do serious destruction.

Also, I know with the time I have available and with where the market is moving, I would much prefer a solution that basically comes in a pre-built box and is ready to bolt on the motors and connect to the computer.

I really like the idea of a full closed loop to the computer system and would probably have fun playing with EMC again.

So, any options for maybe more appropriate powered brushed servos and matching drives that would work with your Universal PWM controller?

Anyone integrating all this stuff into a turnkey package that is ready to go?

While we are talking servos, I would also love to hear from some of the other providers out there that have step and direction servo systems for table top sizes machines using NEMA 23 mounts. I know Fred from IMService does some, but no one seems to be talking about using them. Anyone with any experience with his solution?

Thanks,

Tim Goldstein
A2Z Corp
A2Z CNC division
3955 S Mariposa St
Englewood CO 80110
720 833-9300
Toll Free 877 754-7465

www.A2ZCorp.us/store
USA made accessories for desktop mills & lathes.
Specialized tools for the jewelry industry.