Please help! Joe's 2006 CNC

Todd wrote:

There are a whole lot of ways to wire an 8 lead step motor wrong for a uni-polar drive. Be sure you did it right.

I had a set of 8-wire steppers where the _actual_ wire colours did not match the data sheet in the box that the steppers came in!

You need to work out which pairs of wires are each end of a phase, then which phases are pairs, and which direction is which.

You can do all this without even a multimeter.

1) Find which wires are each end of a winding. You can do this with a multimeter, or try touching together every combination one by one (making sure that only two are connected at a time). Whedn two ends of a winding are connected then the motor will be hard to turn.
Label these as A, B, C, D.

2) Now connect one end of A to one end of B, and connect the other end of A to the other end of B. If the motor is very stiff to turn then A+ is connected to B- and A- to B+. If it is easy to turn, then it might be A+ to B+ and A- to B-, so swap them. If the motor still turns freely, then try A and C as a pair, and then A and D.

3) The unpaired windings must be the other pair, work out the polarity the same way.

You now know which windings are pairs, and which end of each is + and -.