Bridgeport 6F power feed

[tpeters910]

New owner of 1973 series 1 J head with Seco 6F gen A power feed. Nice machine with apparently little use over the years. Was at local shop 4 miles away and got it for decent price at their auction 2 weeks ago. Was told everything worked by owner, but auction co would not allow power on checks to verify prior to auction start. I did look at the electrical tag to verify motor was 220v, but apparently missed that it was single phase till machine was delivered. No issues with that in my home shop, as was planning on buying a VFD for 3 phase conversion that I won't need now.

Now have mill in the new mobile base I built, got it wheeled near final position, and got the power connected yesterday. Motor works fine, spindle quiet, quill feed works good, belt changes all move easily, and minimal backlash. Onto the power feed. Initially worked with handle to right when first tried it out, but wouldn't work to left at all. Turning handle left actually stopped all motor functions till unplugged it, let it sit, plugged it back in and started it again. Couldn't run more than 10s total before it would shut off.

Took feed apart to check everything out. Old style with the power switch, indicator light & circuit board bolted to side of machine, not under feed unit like later ones were. Circuit board looks visually ok, nothing blackened or loose. Took the pot and rapid switch out of feed, dropped the bottom of feed housing to gain access to wiring going to motor. Can see someone has been in there, as some electrical tape used to join wires to motor in there. There are 4 wires going to feed motor, all used. With housing hanging down, everything appears to work normally, even to pot, so must have been loose connection?

What is bothering me is when the feed handle is moved to right, the table moves to left; similarly when handle is moved to left, table goes to right. Seems very odd that it was always backwards as feed was always 110 single phase power, so not related to any 220 3 phase wiring issues. Looks like perhaps newer power cord from bottom feed area to motor, so perhaps motor (or wiring) was changed, hooked it up wrong and couldn't be bothered to waste 20 minutes to correct? Is the fix as simple as reversing the wires feeding the red/ black wires going to motor from bottom of feed?

Used the 6F feeds for years when I was a tool & die maker, but always had a maintenance tech so I was never into one myself before.

 

[tpeters910]

I got further with it today. Looking closely at the wires running from the contact switches to the Boehm 4640 motor, they used a piece of the same 12/4 SO cord that powers the machine (about .730 dia). That was too fat to fit into the gland grip fittings, so they pulled the guts out of the glands and taped the jacket to the gland shell. I found a hand drawn wiring diagram for the Seco feed that showed the left contactor green / white stripe went to the motor green wire, and the right contactor white wire went to the motor white wire. Diagram said the red/black wires went to the brush armatures. So switched the left contactor green/white stripe to the white motor wire, and right contactor white wire to green motor wire. Feed handle rotation now matches the handle selection. So looks like they switched the white/green wire motor wires on the motor armature connections. Since the SO cord was oil soaked and swollen, I took the motor off and pulled the SO wires out.

That heavy replacement SO cord they used was supposed to have originally been SJO 18/4 cord (.330 O.D.) according to a thread I found on here where H&W was helping a member out. At least that seems to make sense as the cord would fit inside the gland fittings.

Anybody know for certain what size the wire from under the feed to the motor is on their 6F-A? Guessing they might be same on all 6F and 8F feeds?

 

[evanthayer]

super long ago but I can answer any questions about the 6F that you have. I am just completing my full restoration.

 

[Don_Hartman]

Your power feed motor looks like a framco . What did you do do about the Bakelite brush holders?

 

[evanthayer]

Brush holders appeared to be copper so may not be a framco?