paroikoi
Aluminum
- Joined
- Oct 2, 2014
- Location
- Jonesboro, AR, USA
Hi all. As I just mentioned in a separate post about making sight glass gaskets, I just got my first 10EE (for my home shop). It is a 1953 MG Navy machine. It's not in great shape, at least cosmetically. I feel like I got a good deal, though, so don't judge it too much in the photos. I haven't fully run it yet, as I'm working through issues. I need to replace the belts and just finished flushing and replacing the various oils. However, it also has electrical problems.
It's a 230V 3-phase machine. When I first tried to start it, the MG ran but the exciter had no voltage. It turned out (I think) to be just worn out carbon brushes on the exciter. Those have now been replaced. Now the MG runs and the exciter will allow the spindle motor to start. But the spindle motor doesn't behave properly.
With the MG running, if I turn the spindle actuation lever (I don't know what that's called, but the lever just below and to the left of the spindle nose) to the left with the speed knob set to the slowest setting, the spindle motor turns clockwise continuously at a fairly slow speed. If I turn the spindle actuation lever to the right, the spindle motor "twitches" briefly counterclockwise and then stops. It never fully rotates. If I turn the speed knob a decent amount faster before starting, turning the lever to the left gets the spindle motor to spin clockwise slowly. Turning the lever to the right gets the spindle motor to spin MUCH FASTER but still clockwise.
While running, turning the speed knob faster does get the spindle motor to spin faster. It also causes more sparking of the spindle motor carbon brushes and there will occasionally be bright flashes (arcing) at the carbon brushes. Also, turning the spindle actuation lever left vs. right does, in fact, cause closure of one vs. the other of the two large relays in the DC controller panel next to the spindle motor. I.e., left does one of the relays and right does the other, so I think the relays are working properly.
Here are a few photos just to show the configuration.
Would anyone have any pointers on where to start next? I've done some Googling and can't find any useful threads that quite match this scenario. Also, I will be at work most of the day tomorrow, so please be patient if I can't reply or troubleshoot again till tomorrow after work.
Thanks in advance,
Josh
It's a 230V 3-phase machine. When I first tried to start it, the MG ran but the exciter had no voltage. It turned out (I think) to be just worn out carbon brushes on the exciter. Those have now been replaced. Now the MG runs and the exciter will allow the spindle motor to start. But the spindle motor doesn't behave properly.
With the MG running, if I turn the spindle actuation lever (I don't know what that's called, but the lever just below and to the left of the spindle nose) to the left with the speed knob set to the slowest setting, the spindle motor turns clockwise continuously at a fairly slow speed. If I turn the spindle actuation lever to the right, the spindle motor "twitches" briefly counterclockwise and then stops. It never fully rotates. If I turn the speed knob a decent amount faster before starting, turning the lever to the left gets the spindle motor to spin clockwise slowly. Turning the lever to the right gets the spindle motor to spin MUCH FASTER but still clockwise.
While running, turning the speed knob faster does get the spindle motor to spin faster. It also causes more sparking of the spindle motor carbon brushes and there will occasionally be bright flashes (arcing) at the carbon brushes. Also, turning the spindle actuation lever left vs. right does, in fact, cause closure of one vs. the other of the two large relays in the DC controller panel next to the spindle motor. I.e., left does one of the relays and right does the other, so I think the relays are working properly.
Here are a few photos just to show the configuration.
Would anyone have any pointers on where to start next? I've done some Googling and can't find any useful threads that quite match this scenario. Also, I will be at work most of the day tomorrow, so please be patient if I can't reply or troubleshoot again till tomorrow after work.
Thanks in advance,
Josh