@Kentamanos wrote:
Art Givens and I looked at it a bit. I’m guessing it’s the DC motor. We never got to the point of powering up the feed an confirming the motor armature and field were getting power, but the PCB looks fine and the switches are working fine. We tried connectivity across the armature and motor field and couldn’t ever get it. It makes me think a coil burned out or something, but I could be way off. The brush on the right side of the motor (when looking at it from the front panel) was pretty worn down and could cause a problem as well.
As far as the working theory on how it works, the switch powers the “motor field” and direction is controlled by the polarity it’s fired up. The mechanical mechanism that activates those switches is pretty neat.
We googled schematics for the control board and how it’s connected to the motor and front panel.
Google search “bridgeport series 1 power feed” and look at images and you’ll find there two (in case you can find higher res versions). The colors on the schematic were fairly accurate. If I remember correctly, the only discrepancy we saw was the color of the wires connecting to the AMP connector pins 1 and 2 had red and black flipped.
I recommend we start pricing a replacement motor but continue to do a bit more diagnosis. If we need to pull the motor, we probably need to drain the oil out of reservoir first (and figure out what sort of oil to put back in later).
PS> Just because I thought it was cool, the switch used to handle forward, neutral and reverse. Notice how the metal will rotate down to activate one of the two switches (little black button under metal) if the center part rotates:
PPS> We printed out the two schematic files and they’re in a catalog on the table with the endmills etc.
PPPS> The brushes are apparently a LOT more worn down than I thought. The carbon on the end of ours was maybe a quarter inch long. Here is what they look like new (which look a LOT longer): http://www.ebay.com/itm/New-Bridgeport-Part-Servo-Powerfeed-Motor-Brushes-Cap-/291021179724
