Re: [CAD_CAM_EDM_DRO] microstep accuracy was what comprises as step

Alan Marconett KM6VV wrote:

> Hi Jon,
>
> I just won a bid on a pair of Sanyo Denki "Super R" DC servo motors.
> The encoder on them is 2000 cpi, and The motor is rated at 300W, 80V,
> 4.8A, 2500 RPM (R730-012W). So I *THINK* I've found my servo motors for
> my RF-31 mill. Not too much on it on the web. The motor is 3" dia with
> a square flange, and the motor is 5" long. Encoder adds another 1.5" to
> the length. Encoder pinout printed on the encoder! I plan to drive it
> with Gecko 340's.
>
> So is this too much for my RF-31? It might be overkill, but since I
> have them, I'll run them!

No, I think this is about right. It depends on whether these are continuous
or peak ratings. My Bridgeport motors are 1/8 Hp continuous rating, and
I get about 1/2 Hp peak.

> I've been looking for the discussions on
> previous servos (I thought I saved a few that I could follow), but I
> haven't found them in my saved emails. I'm thinking of 7/8" ball
> screws, and a short (1:1?) 3/8" ('L') belt. I'd love a discussion of
> the potential of these servos!

with 1:1 drive, you could get about 2000 RPM, or 33 RPS. 33 RPS / 5 TPI
for the ballscrew will give 6.67 IPS, or 400 IPM! Yikes! I think I'd
go for a 2:1 belt reduction, and make the motor's life easier.

Jon