Considering all the talk about steppers, I thought maybe a little off-topic questions would be okay?
I am fabricating a low power backup constant fuel injection system for an engine. It uses a stepper to rotate a barrel valve. The motor is a NEMA 17, unipolar motor, 5mm shaft, 30 ohm coil. Now, in the beginning, this motor ran okay, but it saw some fuel spilled on it (not with electricity), and general wear and tear. I bought several of the same kind to have replacements. I've hacked around and added an index pulse pickup with a hall effect sensor and magnet epoxied directly to the shaft on the back end. I say shaft, but it's there at the bearing because it's not a dual shaft motor. It turns out this motor doesn't have enough torque, and I know one of it's brothers works fine. I have several issues with this motor. The coil resistance is too high, not allowing full torque. I need a dual shaft motor to add a proper encoder, and it needs to be bipolar. Now, this is a difficult thing to find. I was bored today and took apart the motor. Now I know that's a bad thing, and once I did that, the rotors got demagnetized. To the questions: 1) Why does a motor get demagnetized from taking it apart? 2) If a person were able to press the rotors onto a different shaft, or even gang up windings by adding multiple motors to a common shaft, how would an average Joe go about remagnetizing the rotors? I know there are shops that do this, but if I was going that route, I'd just pay for a high dollar motor. 3) Does anyone know where to find a 5mm or .15" dual shaft NEMA17 unipolar motor? I think I could live with a $50 limit. ------------------------------------------------------------------------- Take Surveys. Earn Cash. Influence the Future of IT Join SourceForge.net's Techsay panel and you'll get the chance to share your opinions on IT & business topics through brief surveys-and earn cash http://www.techsay.com/default.php?page=join.php&p=sourceforge&CID=DEVDEV _______________________________________________ Emc-users mailing list Emc-users@lists.sourceforge.net https://lists.sourceforge.net/lists/listinfo/emc-users
