Results 1 to 2 of 2

Thread: Electric Motor Question

  1. #1
    Join Date
    Jun 2007
    Oceanside, So. Calif. 5 mi. to the ocean

    Electric Motor Question


    A few weeks ago I posted about a Porter Cable dry grinder giving problems. Reports I have seen say $45 - $55 to replace the electronics. That is approximately 1/2 of the original cost; it is not a practical solution as far as I am concerned.

    The new PC variable speed dry grinder ran long enough for Glenn and me to put on new wheels, balance and align them. Then it started blowing fuses. Unfortunately I had left it in the box until the warranty was no good.

    What would happen if I just took the pig tail wires and hooked them directly to the motor through the switch and said, "To heck with the variable speed?"

    I assume that the motor will run 3,000+ rpm (yes I know what ASSUME stands for; that is why I am asking for confirmation or any other ideas). I would prefer the 1700+ speed. However 3000+ is better than nothing.

    Thanks and Enjoy,

    If pics would help, I will photo any part you wish to see.
    First of all you have to be smarter than the machine.

  2. #2
    Join Date
    Nov 2006
    Austin, Texas
    As an electrical engineer I know the theory behind the motors but am largely useless with the practical answers.

    But since I know nothing, that has never stopped me. The normal speed is largely dependent on the internal magnetic poles - so if the variable speed was up to 3500 rpm, I bet you will get that higher speed without the controls. If the variable speed was up to 1725 rpm, I bet that will be the speed without controls.
    Charlie Plesums, Austin Texas
    (Retired early to become a custom furnituremaker)
    Lots of my free advice at

Similar Threads

  1. the motor question
    By Mike Kaminsky in forum New Tools
    Replies: 8
    Last Post: 11-10-2015, 02:16 PM
  2. Got an Electrical Motor Question
    By Paul Douglass in forum Off Topic Discussion
    Replies: 8
    Last Post: 09-26-2011, 07:39 PM
  3. Electric Motor
    By Dan Mooney in forum General Woodworking Q&A
    Replies: 6
    Last Post: 08-08-2010, 04:43 AM
  4. Another Motor question??
    By Jeff Bower in forum General Woodworking Q&A
    Replies: 7
    Last Post: 03-25-2008, 12:25 AM
  5. Auto electric question
    By Jeff Horton in forum Off Topic Discussion
    Replies: 13
    Last Post: 08-26-2007, 01:40 AM


Posting Permissions

  • You may not post new threads
  • You may not post replies
  • You may not post attachments
  • You may not edit your posts