CAD CAM EDM DRO - Yahoo Group Archive

Re: How much torque is enough? (Was: COMPLETE 3 axis CNC...)

Posted by ballendo
on 2006-05-02 23:33:02 UTC
Tony,

EXCELLENT POST!

Yep, there's more to this stuff than brute force.

My old 1A, 7.4V 116 oz.in. motors were tooling one of my Sherline
5400 mills around at 45IPM the other day using the new GeoM control
box with its 34VDC and 7062 uni-chopper drives...

Usually they've been running with my old 297/298 drives in modifed
halfstep. They'll go faster, but in that config we run 'em at 40IPM.

Ballendo

--- In CAD_CAM_EDM_DRO@yahoogroups.com, Tony Jeffree <tony@...>
wrote:
>
> At 00:52 03/05/2006, you wrote:
> >P.S. Still amazes me how quickly what once was acceptable becomes
> >insufficient; how "testosterone" seems to have invaded DIY-CNC...
> >I have machines with 150 oz.in motors going 240 IPM, carrying 3HP
> >routers. Sherline's with "only" 116 oz. in. have been making money
> >for me for over a decade. Yet many folks now seem to think that if
> >you don't have the biggest, fastest...
>
> Ballendo -
>
> The problem is that people tend to focus on the motor torque
without
> understanding the effect that other factors (motor inductance,
current
> rating, supply voltage, leadscrew pitch, desired acceleration
rates, etc.
> etc....) will have on the system performance.
>
> I did a very interesting test the other day on my Taig mill.
>
> I bought one of the original Taigs with 140 oz-in motors, rated at
1A/phase
> (something like 7 volts to drive that through the 7 Ohm coil
resistance) -
> it was the first of their mills to be imported to the UK a few
years back.
> A couple of years later I upgraded to their current 200 oz-in
motors -
> still 1A/phase, so even higher coil resistance - ~9 Ohm IIRC. I
recently
> decided to give the mill a makeover, firstly to improve on the
drive
> coupling and bearing end-float adjustment arrangements (which are
> surprisingly bad on the standard mill - my worst axis had about 5
thou
> backlash), and secondly to convert from the old "bi-level chopper"
drive to
> a modern microstepping drive. Having re-vamped the mechanical side
to the
> point where I can no longer measure any backlash, I decided to see
what
> maximum step rate I could achieve with three alternative motors,
using a
> driver capable of unipolar half-stepping at up to 2A/phase and a
24V supply
> (actually one of my Divisionmaster units).
>
> The first motor was one of the "standard" 200 oz-in 1A/phase
motors. The
> max half-step rate with this motor before losing steps was 1250
> half-steps/sec, equating to around 9.4 IPM (20 TPI leadscrews).
>
> The second was a 254 oz-in, 2.5A/phase, so with the reduced (2A)
drive,
> effectively a 211 oz-in motor, so very comparable to the first in
holding
> torque. This managed 4000 half-steps/sec or 30 IPM.
>
> The third was a 140 oz-in, 3A/phase motor; again, with the reduced
drive,
> effectively down-rated to 93 oz-in. This managed 7000 half-
steps/sec, or
> 52.5 IPM.
>
> Needless to say, I will be using the 140 oz-in motors for the
final
> configuration, but will be driving them at their rated 3A/phase
and will be
> using a ~40V supply and a microstepping drive. If you do the math
on what a
> motor like that can deliver through a 20 TPI leadscrew, you reach
the
> conclusion that this combo can quite happily generate a force of
around
> 100-140 Kilos at the tool tip (factoring in leadscrew efficiency
and the
> dynamic torque the motor can generate). I feel that should be more
than
> sufficient for a mill the size of the Taig, and certainly, the
ability to
> do rapids at >50IPM is way more than I will ever need (or will
feel is
> safe!) on this machine.
>
> Regards,
> Tony
>

Discussion Thread

ballendo 2006-05-01 06:07:54 UTC COMPLETE 3 axis CNC electronics package (plug-n-cut, ready to go) John Mickelson 2006-05-01 22:06:06 UTC Re: [CAD_CAM_EDM_DRO] COMPLETE 3 axis CNC electronics package (plug-n-cut, ready to go) Paul Kelly 2006-05-01 22:22:05 UTC RE: [CAD_CAM_EDM_DRO] COMPLETE 3 axis CNC electronics package (plug-n-cut, ready to go) ballendo 2006-05-01 22:43:44 UTC Re: COMPLETE 3 axis CNC electronics package (plug-n-cut, ready to go) juan gelt 2006-05-02 03:21:13 UTC RE: [CAD_CAM_EDM_DRO] COMPLETE 3 axis CNC electronics package (plug-n-cut, ready to go) Graham Stabler 2006-05-02 03:28:47 UTC Re: COMPLETE 3 axis CNC electronics package (plug-n-cut, ready to go) ballendo 2006-05-02 04:26:35 UTC Re: COMPLETE 3 axis CNC electronics package (plug-n-cut, ready to go) Alan Marconett 2006-05-02 08:38:44 UTC RE: [CAD_CAM_EDM_DRO] COMPLETE 3 axis CNC electronics package (plug-n-cut, ready to go) John Mickelson 2006-05-02 10:44:51 UTC Re: [CAD_CAM_EDM_DRO] Re: COMPLETE 3 axis CNC electronics package (plug-n-cut, ready to go) ballendo 2006-05-02 16:54:22 UTC Re: COMPLETE 3 axis CNC electronics package (plug-n-cut, ready to go) Darren Lucke 2006-05-02 17:08:53 UTC Re: [CAD_CAM_EDM_DRO] Re: COMPLETE 3 axis CNC electronics package (plug-n-cut, ready to go) ballendo 2006-05-02 17:14:14 UTC Re: COMPLETE 3 axis CNC electronics package (plug-n-cut, ready to go) Alan Marconett 2006-05-02 18:58:54 UTC Re: [CAD_CAM_EDM_DRO] Re: COMPLETE 3 axis CNC electronics package (plug-n-cut, ready to go) John Dammeyer 2006-05-02 19:17:47 UTC RE: [CAD_CAM_EDM_DRO] Re: COMPLETE 3 axis CNC electronics package (plug-n-cut, ready to go) turbulatordude 2006-05-02 21:21:55 UTC Re: COMPLETE 3 axis CNC electronics package (plug-n-cut, ready to go) Dave Halliday 2006-05-02 21:26:59 UTC RE: [CAD_CAM_EDM_DRO] Re: COMPLETE 3 axis CNC electronics package (plug-n-cut, ready to go) Tony Jeffree 2006-05-02 22:42:55 UTC How much torque is enough? (Was: COMPLETE 3 axis CNC...) Tony Jeffree 2006-05-02 22:46:33 UTC Re: [CAD_CAM_EDM_DRO] Re: COMPLETE 3 axis CNC electronics package (plug-n-cut, ready to go) Andrew Werby 2006-05-02 23:07:24 UTC Re: Re: Re: COMPLETE 3 axis CNC electronics package (plug-n-cut, ready to go) ballendo 2006-05-02 23:33:02 UTC Re: How much torque is enough? (Was: COMPLETE 3 axis CNC...) turbulatordude 2006-05-03 06:13:26 UTC Re: Steppers, bi- vs uni ?? who cares ? turbulatordude 2006-05-03 06:21:50 UTC Re: How much torque is enough? (Was: COMPLETE 3 axis CNC...) Alan Marconett 2006-05-03 08:20:56 UTC RE: Stepper questions Andy Wander 2006-05-03 08:24:55 UTC RE: [CAD_CAM_EDM_DRO] RE: Stepper questions Alan Marconett 2006-05-03 09:01:06 UTC RE: [CAD_CAM_EDM_DRO] RE: Stepper questions Alan Marconett 2006-05-03 09:15:07 UTC RE: [CAD_CAM_EDM_DRO] Re: COMPLETE 3 axis CNC electronics package (plug-n-cut, ready to go) Tony Jeffree 2006-05-03 09:39:28 UTC Re: [CAD_CAM_EDM_DRO] Re: How much torque is enough? (Was: COMPLETE 3 axis CNC...) Roy J. Tellason 2006-05-03 09:42:21 UTC Re: [CAD_CAM_EDM_DRO] RE: Stepper questions Jon Elson 2006-05-03 10:05:16 UTC Re: [CAD_CAM_EDM_DRO] RE: Stepper questions Mariss Freimanis 2006-05-03 10:15:12 UTC Re: Stepper questions Mariss Freimanis 2006-05-03 10:38:26 UTC Re: COMPLETE 3 axis CNC electronics package (plug-n-cut, ready to go) John Dammeyer 2006-05-03 10:43:10 UTC RE: [CAD_CAM_EDM_DRO] RE: Stepper questions Mariss Freimanis 2006-05-03 10:54:30 UTC Re: Stepper questions Phil Mattison 2006-05-03 10:58:44 UTC Re: [CAD_CAM_EDM_DRO] RE: Stepper questions Mariss Freimanis 2006-05-03 11:22:52 UTC Re: Stepper questions Roy J. Tellason 2006-05-03 11:48:38 UTC Re: [CAD_CAM_EDM_DRO] RE: Stepper questions Alan Marconett 2006-05-03 13:24:28 UTC RE: [CAD_CAM_EDM_DRO] RE: Stepper questions Alan Marconett 2006-05-03 13:31:29 UTC RE: [CAD_CAM_EDM_DRO] Re: Stepper questions Alan Marconett 2006-05-03 13:46:49 UTC RE: [CAD_CAM_EDM_DRO] Re: COMPLETE 3 axis CNC electronics package (plug-n-cut, ready to go) Alan Marconett 2006-05-03 14:05:41 UTC RE: [CAD_CAM_EDM_DRO] RE: Stepper questions Alan Marconett 2006-05-03 14:08:49 UTC RE: [CAD_CAM_EDM_DRO] RE: Stepper questions John Dammeyer 2006-05-03 14:47:15 UTC RE: [CAD_CAM_EDM_DRO] RE: Stepper questions ballendo 2006-05-03 15:00:40 UTC Almost plug-n-play??? was Re: Steppers, bi- vs uni ?? who cares ? R Rogers 2006-05-03 15:15:20 UTC Re: [CAD_CAM_EDM_DRO] Almost plug-n-play??? was Re: Steppers, bi- vs uni ?? who cares ? juan gelt 2006-05-03 15:15:51 UTC Re: [CAD_CAM_EDM_DRO] Almost plug-n-play??? was Re: Steppers, bi- vs uni ?? who cares ? ballendo 2006-05-03 16:29:58 UTC The best stepper driver??? was Re: Stepper questions ballendo 2006-05-03 16:46:32 UTC Re: Stepper questions ballendo 2006-05-03 16:48:36 UTC Almost plug-n-play??? was Re: Steppers, bi- vs uni ?? who cares ? ballendo 2006-05-03 16:52:30 UTC Almost plug-n-play??? was Re: Steppers, bi- vs uni ?? who cares ? Wayne Weedon 2006-05-03 16:52:50 UTC Re: [CAD_CAM_EDM_DRO] The best stepper driver??? was Re: Stepper questions R Rogers 2006-05-03 17:19:46 UTC Re: [CAD_CAM_EDM_DRO] The best stepper driver??? was Re: Stepper questions ballendo 2006-05-03 17:41:09 UTC The best stepper driver??? was Re: Stepper questions Mariss Freimanis 2006-05-03 18:04:12 UTC The best stepper driver??? was Re: Stepper questions turbulatordude 2006-05-03 18:16:44 UTC Re: COMPLETE 3 axis CNC electronics package (plug-n-cut, ready to go) Mariss Freimanis 2006-05-03 18:29:22 UTC The best stepper driver??? was Re: Stepper questions turbulatordude 2006-05-03 18:30:10 UTC Almost plug-n-play??? was Re: Steppers, bi- vs uni ?? who cares ? turbulatordude 2006-05-03 18:39:26 UTC The best stepper driver??? was Re: Stepper questions Alan Marconett 2006-05-03 18:54:16 UTC Re: stepper questions Jon Elson 2006-05-03 19:20:11 UTC Re: [CAD_CAM_EDM_DRO] RE: Stepper questions Jon Elson 2006-05-03 19:28:13 UTC Re: [CAD_CAM_EDM_DRO] RE: Stepper questions Jon Elson 2006-05-03 19:40:29 UTC Re: [CAD_CAM_EDM_DRO] RE: Stepper questions jeffalanp 2006-05-03 19:56:40 UTC The best stepper driver??? was Re: Stepper questions juan gelt 2006-05-03 21:48:03 UTC Re: [CAD_CAM_EDM_DRO] Almost plug-n-play??? was Re: Steppers, bi- vs uni ?? who cares ? Mariss Freimanis 2006-05-03 22:00:36 UTC The best stepper driver??? was Re: Stepper questions Mariss Freimanis 2006-05-03 22:46:47 UTC The best stepper driver??? was Re: Stepper questions JanRwl@A... 2006-05-03 22:51:27 UTC Re: [CAD_CAM_EDM_DRO] The best stepper driver??? was Re: Stepper questions Mariss Freimanis 2006-05-03 22:58:10 UTC Almost plug-n-play??? was Re: Steppers, bi- vs uni ?? who cares ? juan gelt 2006-05-04 00:01:41 UTC Re: [CAD_CAM_EDM_DRO] Almost plug-n-play??? was Re: Steppers, bi- vs uni ?? who cares ? Tony Jeffree 2006-05-04 00:08:20 UTC Re: [CAD_CAM_EDM_DRO] Almost plug-n-play??? was Re: Steppers, bi- vs uni ?? who cares ? ballendo 2006-05-04 02:36:42 UTC The best stepper driver??? was Re: Stepper questions ballendo 2006-05-04 02:41:39 UTC The best stepper driver??? was Re: Stepper questions ballendo 2006-05-04 03:20:04 UTC Almost plug-n-play??? was Re: Steppers, bi- vs uni ?? who cares ? Graham Stabler 2006-05-04 03:56:27 UTC Almost plug-n-play??? was Re: Steppers, bi- vs uni ?? who cares ? juan gelt 2006-05-04 04:44:26 UTC Re: [CAD_CAM_EDM_DRO] Almost plug-n-play??? going O.T. juan gelt 2006-05-04 04:54:17 UTC Re: [CAD_CAM_EDM_DRO] Almost plug-n-play??? going O.T. art 2006-05-04 06:40:05 UTC Re: [CAD_CAM_EDM_DRO] Almost plug-n-play??? going O.T. JCullins 2006-05-04 07:07:52 UTC Re: [CAD_CAM_EDM_DRO] Almost plug-n-play??? going O.T. Wayne Weedon 2006-05-04 07:14:27 UTC Re: [CAD_CAM_EDM_DRO] The best stepper driver??? was Re: Stepper questions caudlet 2006-05-04 07:43:32 UTC Re: Almost plug-n-play??? going O.T. {moderator WARNING!} R Rogers 2006-05-04 07:54:58 UTC Re: [CAD_CAM_EDM_DRO] Almost plug-n-play??? was Re: Steppers, bi- vs uni ?? who cares ? jeffalanp 2006-05-04 08:28:48 UTC The best stepper driver??? was Re: Stepper questions jeffalanp 2006-05-04 09:32:27 UTC The best stepper driver??? was Re: Stepper questions Mariss Freimanis 2006-05-04 09:57:55 UTC The best stepper driver??? was Re: Stepper questions Aaron 2006-05-05 08:46:42 UTC Re: [CAD_CAM_EDM_DRO] Re: COMPLETE 3 axis CNC electronics package (plug-n-cut, ready to go) Mariss Freimanis 2006-05-05 09:48:24 UTC Re: COMPLETE 3 axis CNC electronics package (plug-n-cut, ready to go) wthomas@g... 2006-05-05 10:02:41 UTC W.E.T. CAD_CAM_EDM_DRO] : Stepper speed question