On Tue, 10 Apr 2012 21:41:51 -0400 "Kent A. Reed" <[email protected]> wrote:
> On 4/10/2012 3:20 PM, inflo wrote: > > hi, > > > > i think i would go with the mesa setup > > http://www.retrofit-plus.at/store/7i76-plug-n-go#tab-box-product-info > > > > To the 7i76 card i can connect the power supply, or ? > > > > I got a 30V/2A lab-power-supply, which i can use. Can i use just > > one power-supply for all 3 motors ? > > > > > > Can i run stepper or servos with the mesa 7i76 ? i mean, am i > > limited to stepper or servo motors with the mesa cards? > > > > > > You think servos are better than stepper motors ? > > What would be a good torque for small aluminium parts ? Are there > > other things to look for ? With steppers or servos you need to do the engineering to make certain the motors selected have adequate torque,etc. to move your axes at design velocities and with enough force to mill correctly. That is a small machine and relatively diminutive servos would do a great job but the cost will be more that a stepper setup. People get by with steppers all the time but the emc_lists would be rather quiet if everyone used servos just because they don't have the same problems with resonance, etc. One of the guys on the list had some cute 40 W Panasonic servos for sale a few years ago. Don't know if he still has any. They were $175 (drive and servo motor) at the time but I think the price has gone up. I think servos on a small mill would be a real kick but maybe not the best bang for the buck. Just a comment but Al seems to mill about 4X easier than steel. Dave > > > > <...> > > > > flo > > > > > Flo: > > Have you tried using one of the Internet search engines like Google, > Yahoo, or Bing? AFIK bing is just a ping combined with traceroute; really handy! > > When I enter "proxxon mf70" into the Google search line I get pages > of hits related to your mill, including a number of stepper-motor > conversions. I didn't notice any servo-motor conversions off hand, > but I didn't look very hard. In any case, I'm definitely not the > right guy to talk about servo systems. > > I don't know enough about the characteristics of the Proxxon mf70 > mill to recommend a motor size, but I should think you could get some > good ideas from the work described on these other sites turned up by > Google. > > If I were forced to guess, here's how I would start: > > From the posted pictures, the mf70 looks relatively diminutive. > > These days, the somewhat more massive Taig tabletop mill in CNC form > ships with NEMA frame size 23 stepper motors rated at 200 ozf-in (a > bit more than 1.4 newton-meter) holding torque [some think that is > already overkill. YMMV]. I'd be surprised if your mill requires > motors this powerful. > > Sherline ships its mill in CNC form with NEMA frame size 23 stepper > motors rated at 135 ozf-in (0.95 newton-meter). I'd think this is > good enough for your mill, but you still need to do the homework. > > It's even possible the holding-torque requirement for your mill is > low enough that the relatively smaller NEMA frame size 17 motors > could be used. > > Good hunting! > > Regards, > Kent > > > PS - you may want to ask your questions on the emc-users list. The > readers of that list represent a wide spectrum of machines and their > usage. They are eager to help each other bring up new machines. > > ------------------------------------------------------------------------------ > Better than sec? Nothing is better than sec when it comes to > monitoring Big Data applications. Try Boundary one-second > resolution app monitoring today. Free. > http://p.sf.net/sfu/Boundary-dev2dev > _______________________________________________ > Emc-developers mailing list > [email protected] > https://lists.sourceforge.net/lists/listinfo/emc-developers ------------------------------------------------------------------------------ Better than sec? Nothing is better than sec when it comes to monitoring Big Data applications. Try Boundary one-second resolution app monitoring today. Free. http://p.sf.net/sfu/Boundary-dev2dev _______________________________________________ Emc-developers mailing list [email protected] https://lists.sourceforge.net/lists/listinfo/emc-developers
