On Thursday 11 December 2014 07:56:51 Todd Zuercher did opine And Gene did reply: > Also remember that a larger stepper usually isn't going to be able to > go quite as fast as a smaller one.
I thought that too, and had the old motor limited to 22 ipm because I only have 28 volts for motor power. That will be fixed in the next month as I have some 48 volt supplies coming that I will rework into a supply per motor system since they are only 3.5 amp rated supplies. If I can turn them down to 45 volts, the 50 volt rated drivers should be ok. The thought also crossed my mind to parallel them, with .1 ohm isolation R's into a good sized capacitor and treat them as one supply If I can get the voltages to match. That might stop any surge shutdowns they may do because at one point I was using a cheap switcher, two of them in series, to get the volts I needed, but the back dump from the motors kept shutting them off, one at a time. Weird effect then, the motor could turn, but only at about 10 rpm. This bigger one seems happy at that speed limit, but is considerably noisier than the older, weaker motor was. I wish now that I had built the end rings that hold all this together with a locking setscrew, with threads so I could turn it on the threads for a more precise adjustment. I have to go make a duplicate of the jig setup I made last night, but will tighten up the clamp ring as far as I can compress it by hand before I do, to see if that reduces/stops the rattling at mid speed noise. I read up on the "rattler" version last night, and may make one of them for testing, but will mill for a inner and outer o-rings on both faces to seal in the heavy grease or STP I'll put in the pockets that hold the weights. Seems to me that may be a better design than these but use the viscosity of the grease or STP as energy absorber. That should stop the rattling while still doing its job. The size of the hole containing the weight roller vs the size of the roller strikes me as being important and shouldn't be more than the equ of a single step at that radii for clearance. The step being 1.8 degrees of course. All that of course if this tightening of what I have doesn't bring the noise under control. Thanks Todd. > ----- Original Message ----- > From: "Gene Heskett" <ghesk...@wdtv.com> > To: "Enhanced Machine Controller (EMC)" > <emc-users@lists.sourceforge.net> Sent: Thursday, December 11, 2014 > 6:45:14 AM > Subject: [Emc-users] Damper Q? > > Hello all again; > > Those who use the big stack of heavy fender washers, held between > rubber washers that fit the hub tightly, on a long drum that holds > about a 2" stack of these might be able to comment here. > > This bigger motor seems quite a bit noisier that the old 252 oz/in > motor was, and much of it seems to be coming from the damper, which I > haven't adjusted the clamping pressure on the stack for quite a while. > Its rattling, and I note that the washers are fairly easy to turn. So > obviously as a torsional vibration absorber they are not working at > all well. And the mill I believe is being speed restricted because of > that. > > How hard do you folks clamp them up? Is there a generalized rule of > thumb, or is it closer to black magic to "get it right"? > > Cheers, Gene Heskett Cheers, Gene Heskett -- "There are four boxes to be used in defense of liberty: soap, ballot, jury, and ammo. Please use in that order." -Ed Howdershelt (Author) Genes Web page <http://geneslinuxbox.net:6309/gene> US V Castleman, SCOTUS, Mar 2014 is grounds for Impeaching SCOTUS ------------------------------------------------------------------------------ Download BIRT iHub F-Type - The Free Enterprise-Grade BIRT Server from Actuate! Instantly Supercharge Your Business Reports and Dashboards with Interactivity, Sharing, Native Excel Exports, App Integration & more Get technology previously reserved for billion-dollar corporations, FREE http://pubads.g.doubleclick.net/gampad/clk?id=164703151&iu=/4140/ostg.clktrk _______________________________________________ Emc-users mailing list Emc-users@lists.sourceforge.net https://lists.sourceforge.net/lists/listinfo/emc-users
