On Wed, 2009-06-03 at 17:17 -0700, Rafael Skodlar wrote: > Kirk Wallace wrote: > > Just in case someone wants to see inside a brushless motor: > > http://www.wallacecompany.com/machine_shop/Wantai/ > > > > Was there a particular reason to take it apart? I remember companies > warning you about destroying stepper motor, permanent magnet to be > exact, if you take it apart. > http://www.cnczone.com/forums/showthread.php?t=903 > > Not sure if this applies to brushless motors though.
I think the problem with demagnetizing the rotors is due to the magnetic material used. Some materials may have strong magnetism, but can't hold the direction beyond a certain point, which can be good or bad. The manufacturer can make a rotor then just before assembling the motor magnetize it. I suppose it's possible, the rotor could even be magnetized after assembly. Some materials will lose their magnetism with heat, alinco is known to be the most heat resistant of the common motor materials. Rubbing or bumping seems to be another way to affect a material's magnetism. You can magnetize nails and screw drivers this way, so rubbing or bumping a stepper rotor may be unwise. A television screen, recording heads and anything magnetized, can be de-magnetized with an alternating field if it's strong enough. It's hard to find someone with first hand experience, I certainly don't, but it seems the most stories about losing magnetism concern old magnetos, mower engine flywheels, and older steppers, but I could be wrong. For my brushless motor I didn't remove the rotor, because I was unable to. I suspect the manufacturer uses a fixture to install and remove these rotors. -- Kirk Wallace http://www.wallacecompany.com/machine_shop/ http://www.wallacecompany.com/E45/index.html California, USA ------------------------------------------------------------------------------ OpenSolaris 2009.06 is a cutting edge operating system for enterprises looking to deploy the next generation of Solaris that includes the latest innovations from Sun and the OpenSource community. Download a copy and enjoy capabilities such as Networking, Storage and Virtualization. Go to: http://p.sf.net/sfu/opensolaris-get _______________________________________________ Emc-users mailing list [email protected] https://lists.sourceforge.net/lists/listinfo/emc-users
