Re: [CAD_CAM_EDM_DRO] Re: VFD for a 15HP CNC lathe

Marv Frankel wrote:

>
> Scott,
> Are you sure you didn't forget the decimal point? 15HP is more than
> any lathe I've ever run, and some of them were pretty big.
>
> Marv Frankel

My two Jones & Lamsons (cnc lathes) have 30 HP DC spindle motors. Actually only
have one now (had to scrap one of those this spring due to lack of space), but
kept the motor as a spare (about the size of a 45 gallon drum!).

I was just driving it with a 5 HP DC drive while it was still in testing, so I never
did resolve how to drive the spindle at 30 HP. Yup, pretty big mothers. Pretty sad
to scrap it, but I kept the one with twin turrets (even bigger than the first!).

It was the scrapped lathe that had 5 HP X & Z servo drives (60 amp peak, 65VDC) and the
Gecko G340 drove them just fine at 20amps & 65VDC (using my 1.5KW power supply configured
for 65VDC) at 50 millionths (of an inch step) on Z and 25 millions on the X axis. And by
god it was measurable and repeatable with a 'tenths' dial indicator! The carriage
weighed maybe 1500 lbs with no tools on it.....

Doug Fortune
http://www.cncKITS.com


















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